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2755 lines
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2755 lines
150 KiB
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// License Agreement |
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// For Open Source Computer Vision Library |
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// Copyright (C) 2000-2008, Intel Corporation, all rights reserved. |
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// Copyright (C) 2009, Willow Garage Inc., all rights reserved. |
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// Copyright (C) 2013, OpenCV Foundation, all rights reserved. |
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//M*/ |
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#ifndef OPENCV_CALIB3D_HPP |
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#define OPENCV_CALIB3D_HPP |
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#include "opencv2/core.hpp" |
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#include "opencv2/features2d.hpp" |
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#include "opencv2/core/affine.hpp" |
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/** |
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@defgroup calib3d Camera Calibration and 3D Reconstruction |
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The functions in this section use a so-called pinhole camera model. In this model, a scene view is |
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formed by projecting 3D points into the image plane using a perspective transformation. |
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\f[s \; m' = A [R|t] M'\f] |
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or |
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\f[s \vecthree{u}{v}{1} = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1} |
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\begin{bmatrix} |
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r_{11} & r_{12} & r_{13} & t_1 \\ |
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r_{21} & r_{22} & r_{23} & t_2 \\ |
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r_{31} & r_{32} & r_{33} & t_3 |
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\end{bmatrix} |
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\begin{bmatrix} |
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X \\ |
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Y \\ |
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Z \\ |
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1 |
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\end{bmatrix}\f] |
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where: |
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- \f$(X, Y, Z)\f$ are the coordinates of a 3D point in the world coordinate space |
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- \f$(u, v)\f$ are the coordinates of the projection point in pixels |
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- \f$A\f$ is a camera matrix, or a matrix of intrinsic parameters |
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- \f$(cx, cy)\f$ is a principal point that is usually at the image center |
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- \f$fx, fy\f$ are the focal lengths expressed in pixel units. |
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Thus, if an image from the camera is scaled by a factor, all of these parameters should be scaled |
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(multiplied/divided, respectively) by the same factor. The matrix of intrinsic parameters does not |
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depend on the scene viewed. So, once estimated, it can be re-used as long as the focal length is |
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fixed (in case of zoom lens). The joint rotation-translation matrix \f$[R|t]\f$ is called a matrix of |
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extrinsic parameters. It is used to describe the camera motion around a static scene, or vice versa, |
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rigid motion of an object in front of a still camera. That is, \f$[R|t]\f$ translates coordinates of a |
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point \f$(X, Y, Z)\f$ to a coordinate system, fixed with respect to the camera. The transformation above |
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is equivalent to the following (when \f$z \ne 0\f$ ): |
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\f[\begin{array}{l} |
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\vecthree{x}{y}{z} = R \vecthree{X}{Y}{Z} + t \\ |
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x' = x/z \\ |
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y' = y/z \\ |
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u = f_x*x' + c_x \\ |
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v = f_y*y' + c_y |
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\end{array}\f] |
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The following figure illustrates the pinhole camera model. |
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![Pinhole camera model](pics/pinhole_camera_model.png) |
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Real lenses usually have some distortion, mostly radial distortion and slight tangential distortion. |
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So, the above model is extended as: |
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\f[\begin{array}{l} |
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\vecthree{x}{y}{z} = R \vecthree{X}{Y}{Z} + t \\ |
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x' = x/z \\ |
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y' = y/z \\ |
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x'' = x' \frac{1 + k_1 r^2 + k_2 r^4 + k_3 r^6}{1 + k_4 r^2 + k_5 r^4 + k_6 r^6} + 2 p_1 x' y' + p_2(r^2 + 2 x'^2) + s_1 r^2 + s_2 r^4 \\ |
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y'' = y' \frac{1 + k_1 r^2 + k_2 r^4 + k_3 r^6}{1 + k_4 r^2 + k_5 r^4 + k_6 r^6} + p_1 (r^2 + 2 y'^2) + 2 p_2 x' y' + s_3 r^2 + s_4 r^4 \\ |
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\text{where} \quad r^2 = x'^2 + y'^2 \\ |
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u = f_x*x'' + c_x \\ |
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v = f_y*y'' + c_y |
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\end{array}\f] |
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\f$k_1\f$, \f$k_2\f$, \f$k_3\f$, \f$k_4\f$, \f$k_5\f$, and \f$k_6\f$ are radial distortion coefficients. \f$p_1\f$ and \f$p_2\f$ are |
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tangential distortion coefficients. \f$s_1\f$, \f$s_2\f$, \f$s_3\f$, and \f$s_4\f$, are the thin prism distortion |
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coefficients. Higher-order coefficients are not considered in OpenCV. |
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The next figure shows two common types of radial distortion: barrel distortion (typically \f$ k_1 > 0 \f$) and pincushion distortion (typically \f$ k_1 < 0 \f$). |
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![](pics/distortion_examples.png) |
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In some cases the image sensor may be tilted in order to focus an oblique plane in front of the |
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camera (Scheimpfug condition). This can be useful for particle image velocimetry (PIV) or |
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triangulation with a laser fan. The tilt causes a perspective distortion of \f$x''\f$ and |
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\f$y''\f$. This distortion can be modelled in the following way, see e.g. @cite Louhichi07. |
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\f[\begin{array}{l} |
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s\vecthree{x'''}{y'''}{1} = |
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\vecthreethree{R_{33}(\tau_x, \tau_y)}{0}{-R_{13}(\tau_x, \tau_y)} |
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{0}{R_{33}(\tau_x, \tau_y)}{-R_{23}(\tau_x, \tau_y)} |
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{0}{0}{1} R(\tau_x, \tau_y) \vecthree{x''}{y''}{1}\\ |
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u = f_x*x''' + c_x \\ |
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v = f_y*y''' + c_y |
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\end{array}\f] |
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where the matrix \f$R(\tau_x, \tau_y)\f$ is defined by two rotations with angular parameter \f$\tau_x\f$ |
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and \f$\tau_y\f$, respectively, |
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\f[ |
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R(\tau_x, \tau_y) = |
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\vecthreethree{\cos(\tau_y)}{0}{-\sin(\tau_y)}{0}{1}{0}{\sin(\tau_y)}{0}{\cos(\tau_y)} |
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\vecthreethree{1}{0}{0}{0}{\cos(\tau_x)}{\sin(\tau_x)}{0}{-\sin(\tau_x)}{\cos(\tau_x)} = |
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\vecthreethree{\cos(\tau_y)}{\sin(\tau_y)\sin(\tau_x)}{-\sin(\tau_y)\cos(\tau_x)} |
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{0}{\cos(\tau_x)}{\sin(\tau_x)} |
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{\sin(\tau_y)}{-\cos(\tau_y)\sin(\tau_x)}{\cos(\tau_y)\cos(\tau_x)}. |
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\f] |
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In the functions below the coefficients are passed or returned as |
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\f[(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f] |
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|
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vector. That is, if the vector contains four elements, it means that \f$k_3=0\f$ . The distortion |
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coefficients do not depend on the scene viewed. Thus, they also belong to the intrinsic camera |
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parameters. And they remain the same regardless of the captured image resolution. If, for example, a |
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camera has been calibrated on images of 320 x 240 resolution, absolutely the same distortion |
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coefficients can be used for 640 x 480 images from the same camera while \f$f_x\f$, \f$f_y\f$, \f$c_x\f$, and |
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\f$c_y\f$ need to be scaled appropriately. |
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The functions below use the above model to do the following: |
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- Project 3D points to the image plane given intrinsic and extrinsic parameters. |
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- Compute extrinsic parameters given intrinsic parameters, a few 3D points, and their |
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projections. |
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- Estimate intrinsic and extrinsic camera parameters from several views of a known calibration |
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pattern (every view is described by several 3D-2D point correspondences). |
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- Estimate the relative position and orientation of the stereo camera "heads" and compute the |
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*rectification* transformation that makes the camera optical axes parallel. |
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@note |
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- A calibration sample for 3 cameras in horizontal position can be found at |
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opencv_source_code/samples/cpp/3calibration.cpp |
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- A calibration sample based on a sequence of images can be found at |
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opencv_source_code/samples/cpp/calibration.cpp |
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- A calibration sample in order to do 3D reconstruction can be found at |
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opencv_source_code/samples/cpp/build3dmodel.cpp |
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- A calibration sample of an artificially generated camera and chessboard patterns can be |
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found at opencv_source_code/samples/cpp/calibration_artificial.cpp |
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- A calibration example on stereo calibration can be found at |
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opencv_source_code/samples/cpp/stereo_calib.cpp |
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- A calibration example on stereo matching can be found at |
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opencv_source_code/samples/cpp/stereo_match.cpp |
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- (Python) A camera calibration sample can be found at |
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opencv_source_code/samples/python/calibrate.py |
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@{ |
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@defgroup calib3d_fisheye Fisheye camera model |
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Definitions: Let P be a point in 3D of coordinates X in the world reference frame (stored in the |
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matrix X) The coordinate vector of P in the camera reference frame is: |
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\f[Xc = R X + T\f] |
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where R is the rotation matrix corresponding to the rotation vector om: R = rodrigues(om); call x, y |
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and z the 3 coordinates of Xc: |
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\f[x = Xc_1 \\ y = Xc_2 \\ z = Xc_3\f] |
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The pinhole projection coordinates of P is [a; b] where |
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\f[a = x / z \ and \ b = y / z \\ r^2 = a^2 + b^2 \\ \theta = atan(r)\f] |
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Fisheye distortion: |
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\f[\theta_d = \theta (1 + k_1 \theta^2 + k_2 \theta^4 + k_3 \theta^6 + k_4 \theta^8)\f] |
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The distorted point coordinates are [x'; y'] where |
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\f[x' = (\theta_d / r) a \\ y' = (\theta_d / r) b \f] |
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Finally, conversion into pixel coordinates: The final pixel coordinates vector [u; v] where: |
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\f[u = f_x (x' + \alpha y') + c_x \\ |
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v = f_y y' + c_y\f] |
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@defgroup calib3d_c C API |
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@} |
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*/ |
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namespace cv |
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{ |
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//! @addtogroup calib3d |
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//! @{ |
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//! type of the robust estimation algorithm |
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enum { LMEDS = 4, //!< least-median of squares algorithm |
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RANSAC = 8, //!< RANSAC algorithm |
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RHO = 16 //!< RHO algorithm |
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}; |
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enum { SOLVEPNP_ITERATIVE = 0, |
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SOLVEPNP_EPNP = 1, //!< EPnP: Efficient Perspective-n-Point Camera Pose Estimation @cite lepetit2009epnp |
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SOLVEPNP_P3P = 2, //!< Complete Solution Classification for the Perspective-Three-Point Problem @cite gao2003complete |
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SOLVEPNP_DLS = 3, //!< A Direct Least-Squares (DLS) Method for PnP @cite hesch2011direct |
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SOLVEPNP_UPNP = 4, //!< Exhaustive Linearization for Robust Camera Pose and Focal Length Estimation @cite penate2013exhaustive |
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SOLVEPNP_AP3P = 5, //!< An Efficient Algebraic Solution to the Perspective-Three-Point Problem @cite Ke17 |
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SOLVEPNP_MAX_COUNT //!< Used for count |
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}; |
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enum { CALIB_CB_ADAPTIVE_THRESH = 1, |
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CALIB_CB_NORMALIZE_IMAGE = 2, |
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CALIB_CB_FILTER_QUADS = 4, |
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CALIB_CB_FAST_CHECK = 8, |
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CALIB_CB_EXHAUSTIVE = 16, |
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CALIB_CB_ACCURACY = 32 |
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}; |
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enum { CALIB_CB_SYMMETRIC_GRID = 1, |
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CALIB_CB_ASYMMETRIC_GRID = 2, |
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CALIB_CB_CLUSTERING = 4 |
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}; |
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enum { CALIB_USE_INTRINSIC_GUESS = 0x00001, |
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CALIB_FIX_ASPECT_RATIO = 0x00002, |
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CALIB_FIX_PRINCIPAL_POINT = 0x00004, |
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CALIB_ZERO_TANGENT_DIST = 0x00008, |
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CALIB_FIX_FOCAL_LENGTH = 0x00010, |
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CALIB_FIX_K1 = 0x00020, |
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CALIB_FIX_K2 = 0x00040, |
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CALIB_FIX_K3 = 0x00080, |
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CALIB_FIX_K4 = 0x00800, |
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CALIB_FIX_K5 = 0x01000, |
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CALIB_FIX_K6 = 0x02000, |
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CALIB_RATIONAL_MODEL = 0x04000, |
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CALIB_THIN_PRISM_MODEL = 0x08000, |
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CALIB_FIX_S1_S2_S3_S4 = 0x10000, |
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CALIB_TILTED_MODEL = 0x40000, |
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CALIB_FIX_TAUX_TAUY = 0x80000, |
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CALIB_USE_QR = 0x100000, //!< use QR instead of SVD decomposition for solving. Faster but potentially less precise |
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CALIB_FIX_TANGENT_DIST = 0x200000, |
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// only for stereo |
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CALIB_FIX_INTRINSIC = 0x00100, |
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CALIB_SAME_FOCAL_LENGTH = 0x00200, |
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// for stereo rectification |
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CALIB_ZERO_DISPARITY = 0x00400, |
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CALIB_USE_LU = (1 << 17), //!< use LU instead of SVD decomposition for solving. much faster but potentially less precise |
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CALIB_USE_EXTRINSIC_GUESS = (1 << 22), //!< for stereoCalibrate |
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}; |
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//! the algorithm for finding fundamental matrix |
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enum { FM_7POINT = 1, //!< 7-point algorithm |
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FM_8POINT = 2, //!< 8-point algorithm |
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FM_LMEDS = 4, //!< least-median algorithm. 7-point algorithm is used. |
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FM_RANSAC = 8 //!< RANSAC algorithm. It needs at least 15 points. 7-point algorithm is used. |
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}; |
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/** @brief Converts a rotation matrix to a rotation vector or vice versa. |
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@param src Input rotation vector (3x1 or 1x3) or rotation matrix (3x3). |
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@param dst Output rotation matrix (3x3) or rotation vector (3x1 or 1x3), respectively. |
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@param jacobian Optional output Jacobian matrix, 3x9 or 9x3, which is a matrix of partial |
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derivatives of the output array components with respect to the input array components. |
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\f[\begin{array}{l} \theta \leftarrow norm(r) \\ r \leftarrow r/ \theta \\ R = \cos{\theta} I + (1- \cos{\theta} ) r r^T + \sin{\theta} \vecthreethree{0}{-r_z}{r_y}{r_z}{0}{-r_x}{-r_y}{r_x}{0} \end{array}\f] |
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Inverse transformation can be also done easily, since |
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\f[\sin ( \theta ) \vecthreethree{0}{-r_z}{r_y}{r_z}{0}{-r_x}{-r_y}{r_x}{0} = \frac{R - R^T}{2}\f] |
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A rotation vector is a convenient and most compact representation of a rotation matrix (since any |
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rotation matrix has just 3 degrees of freedom). The representation is used in the global 3D geometry |
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optimization procedures like calibrateCamera, stereoCalibrate, or solvePnP . |
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*/ |
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CV_EXPORTS_W void Rodrigues( InputArray src, OutputArray dst, OutputArray jacobian = noArray() ); |
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/** @example samples/cpp/tutorial_code/features2D/Homography/pose_from_homography.cpp |
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An example program about pose estimation from coplanar points |
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Check @ref tutorial_homography "the corresponding tutorial" for more details |
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*/ |
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/** @brief Finds a perspective transformation between two planes. |
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@param srcPoints Coordinates of the points in the original plane, a matrix of the type CV_32FC2 |
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or vector\<Point2f\> . |
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@param dstPoints Coordinates of the points in the target plane, a matrix of the type CV_32FC2 or |
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a vector\<Point2f\> . |
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@param method Method used to compute a homography matrix. The following methods are possible: |
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- **0** - a regular method using all the points, i.e., the least squares method |
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- **RANSAC** - RANSAC-based robust method |
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- **LMEDS** - Least-Median robust method |
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- **RHO** - PROSAC-based robust method |
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@param ransacReprojThreshold Maximum allowed reprojection error to treat a point pair as an inlier |
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(used in the RANSAC and RHO methods only). That is, if |
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\f[\| \texttt{dstPoints} _i - \texttt{convertPointsHomogeneous} ( \texttt{H} * \texttt{srcPoints} _i) \|_2 > \texttt{ransacReprojThreshold}\f] |
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then the point \f$i\f$ is considered as an outlier. If srcPoints and dstPoints are measured in pixels, |
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it usually makes sense to set this parameter somewhere in the range of 1 to 10. |
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@param mask Optional output mask set by a robust method ( RANSAC or LMEDS ). Note that the input |
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mask values are ignored. |
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@param maxIters The maximum number of RANSAC iterations. |
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@param confidence Confidence level, between 0 and 1. |
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The function finds and returns the perspective transformation \f$H\f$ between the source and the |
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destination planes: |
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\f[s_i \vecthree{x'_i}{y'_i}{1} \sim H \vecthree{x_i}{y_i}{1}\f] |
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so that the back-projection error |
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\f[\sum _i \left ( x'_i- \frac{h_{11} x_i + h_{12} y_i + h_{13}}{h_{31} x_i + h_{32} y_i + h_{33}} \right )^2+ \left ( y'_i- \frac{h_{21} x_i + h_{22} y_i + h_{23}}{h_{31} x_i + h_{32} y_i + h_{33}} \right )^2\f] |
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is minimized. If the parameter method is set to the default value 0, the function uses all the point |
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pairs to compute an initial homography estimate with a simple least-squares scheme. |
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However, if not all of the point pairs ( \f$srcPoints_i\f$, \f$dstPoints_i\f$ ) fit the rigid perspective |
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transformation (that is, there are some outliers), this initial estimate will be poor. In this case, |
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you can use one of the three robust methods. The methods RANSAC, LMeDS and RHO try many different |
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random subsets of the corresponding point pairs (of four pairs each, collinear pairs are discarded), estimate the homography matrix |
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using this subset and a simple least-squares algorithm, and then compute the quality/goodness of the |
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computed homography (which is the number of inliers for RANSAC or the least median re-projection error for |
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LMeDS). The best subset is then used to produce the initial estimate of the homography matrix and |
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the mask of inliers/outliers. |
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Regardless of the method, robust or not, the computed homography matrix is refined further (using |
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inliers only in case of a robust method) with the Levenberg-Marquardt method to reduce the |
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re-projection error even more. |
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The methods RANSAC and RHO can handle practically any ratio of outliers but need a threshold to |
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distinguish inliers from outliers. The method LMeDS does not need any threshold but it works |
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correctly only when there are more than 50% of inliers. Finally, if there are no outliers and the |
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noise is rather small, use the default method (method=0). |
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The function is used to find initial intrinsic and extrinsic matrices. Homography matrix is |
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determined up to a scale. Thus, it is normalized so that \f$h_{33}=1\f$. Note that whenever an \f$H\f$ matrix |
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cannot be estimated, an empty one will be returned. |
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@sa |
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getAffineTransform, estimateAffine2D, estimateAffinePartial2D, getPerspectiveTransform, warpPerspective, |
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perspectiveTransform |
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*/ |
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CV_EXPORTS_W Mat findHomography( InputArray srcPoints, InputArray dstPoints, |
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int method = 0, double ransacReprojThreshold = 3, |
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OutputArray mask=noArray(), const int maxIters = 2000, |
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const double confidence = 0.995); |
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/** @overload */ |
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CV_EXPORTS Mat findHomography( InputArray srcPoints, InputArray dstPoints, |
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OutputArray mask, int method = 0, double ransacReprojThreshold = 3 ); |
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/** @brief Computes an RQ decomposition of 3x3 matrices. |
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@param src 3x3 input matrix. |
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@param mtxR Output 3x3 upper-triangular matrix. |
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@param mtxQ Output 3x3 orthogonal matrix. |
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@param Qx Optional output 3x3 rotation matrix around x-axis. |
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@param Qy Optional output 3x3 rotation matrix around y-axis. |
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@param Qz Optional output 3x3 rotation matrix around z-axis. |
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The function computes a RQ decomposition using the given rotations. This function is used in |
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decomposeProjectionMatrix to decompose the left 3x3 submatrix of a projection matrix into a camera |
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and a rotation matrix. |
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It optionally returns three rotation matrices, one for each axis, and the three Euler angles in |
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degrees (as the return value) that could be used in OpenGL. Note, there is always more than one |
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sequence of rotations about the three principal axes that results in the same orientation of an |
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object, e.g. see @cite Slabaugh . Returned tree rotation matrices and corresponding three Euler angles |
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are only one of the possible solutions. |
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*/ |
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CV_EXPORTS_W Vec3d RQDecomp3x3( InputArray src, OutputArray mtxR, OutputArray mtxQ, |
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OutputArray Qx = noArray(), |
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OutputArray Qy = noArray(), |
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OutputArray Qz = noArray()); |
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|
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/** @brief Decomposes a projection matrix into a rotation matrix and a camera matrix. |
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@param projMatrix 3x4 input projection matrix P. |
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@param cameraMatrix Output 3x3 camera matrix K. |
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@param rotMatrix Output 3x3 external rotation matrix R. |
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@param transVect Output 4x1 translation vector T. |
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@param rotMatrixX Optional 3x3 rotation matrix around x-axis. |
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@param rotMatrixY Optional 3x3 rotation matrix around y-axis. |
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@param rotMatrixZ Optional 3x3 rotation matrix around z-axis. |
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@param eulerAngles Optional three-element vector containing three Euler angles of rotation in |
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degrees. |
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|
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The function computes a decomposition of a projection matrix into a calibration and a rotation |
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matrix and the position of a camera. |
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|
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It optionally returns three rotation matrices, one for each axis, and three Euler angles that could |
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be used in OpenGL. Note, there is always more than one sequence of rotations about the three |
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principal axes that results in the same orientation of an object, e.g. see @cite Slabaugh . Returned |
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tree rotation matrices and corresponding three Euler angles are only one of the possible solutions. |
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The function is based on RQDecomp3x3 . |
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*/ |
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CV_EXPORTS_W void decomposeProjectionMatrix( InputArray projMatrix, OutputArray cameraMatrix, |
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OutputArray rotMatrix, OutputArray transVect, |
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OutputArray rotMatrixX = noArray(), |
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OutputArray rotMatrixY = noArray(), |
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OutputArray rotMatrixZ = noArray(), |
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OutputArray eulerAngles =noArray() ); |
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|
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/** @brief Computes partial derivatives of the matrix product for each multiplied matrix. |
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@param A First multiplied matrix. |
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@param B Second multiplied matrix. |
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@param dABdA First output derivative matrix d(A\*B)/dA of size |
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\f$\texttt{A.rows*B.cols} \times {A.rows*A.cols}\f$ . |
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@param dABdB Second output derivative matrix d(A\*B)/dB of size |
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\f$\texttt{A.rows*B.cols} \times {B.rows*B.cols}\f$ . |
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|
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The function computes partial derivatives of the elements of the matrix product \f$A*B\f$ with regard to |
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the elements of each of the two input matrices. The function is used to compute the Jacobian |
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matrices in stereoCalibrate but can also be used in any other similar optimization function. |
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*/ |
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CV_EXPORTS_W void matMulDeriv( InputArray A, InputArray B, OutputArray dABdA, OutputArray dABdB ); |
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|
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/** @brief Combines two rotation-and-shift transformations. |
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@param rvec1 First rotation vector. |
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@param tvec1 First translation vector. |
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@param rvec2 Second rotation vector. |
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@param tvec2 Second translation vector. |
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@param rvec3 Output rotation vector of the superposition. |
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@param tvec3 Output translation vector of the superposition. |
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@param dr3dr1 |
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@param dr3dt1 |
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@param dr3dr2 |
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@param dr3dt2 |
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@param dt3dr1 |
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@param dt3dt1 |
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@param dt3dr2 |
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@param dt3dt2 Optional output derivatives of rvec3 or tvec3 with regard to rvec1, rvec2, tvec1 and |
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tvec2, respectively. |
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The functions compute: |
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|
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\f[\begin{array}{l} \texttt{rvec3} = \mathrm{rodrigues} ^{-1} \left ( \mathrm{rodrigues} ( \texttt{rvec2} ) \cdot \mathrm{rodrigues} ( \texttt{rvec1} ) \right ) \\ \texttt{tvec3} = \mathrm{rodrigues} ( \texttt{rvec2} ) \cdot \texttt{tvec1} + \texttt{tvec2} \end{array} ,\f] |
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|
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where \f$\mathrm{rodrigues}\f$ denotes a rotation vector to a rotation matrix transformation, and |
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\f$\mathrm{rodrigues}^{-1}\f$ denotes the inverse transformation. See Rodrigues for details. |
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|
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Also, the functions can compute the derivatives of the output vectors with regards to the input |
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vectors (see matMulDeriv ). The functions are used inside stereoCalibrate but can also be used in |
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your own code where Levenberg-Marquardt or another gradient-based solver is used to optimize a |
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function that contains a matrix multiplication. |
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*/ |
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CV_EXPORTS_W void composeRT( InputArray rvec1, InputArray tvec1, |
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InputArray rvec2, InputArray tvec2, |
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OutputArray rvec3, OutputArray tvec3, |
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OutputArray dr3dr1 = noArray(), OutputArray dr3dt1 = noArray(), |
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OutputArray dr3dr2 = noArray(), OutputArray dr3dt2 = noArray(), |
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OutputArray dt3dr1 = noArray(), OutputArray dt3dt1 = noArray(), |
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OutputArray dt3dr2 = noArray(), OutputArray dt3dt2 = noArray() ); |
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|
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/** @brief Projects 3D points to an image plane. |
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@param objectPoints Array of object points, 3xN/Nx3 1-channel or 1xN/Nx1 3-channel (or |
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vector\<Point3f\> ), where N is the number of points in the view. |
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@param rvec Rotation vector. See Rodrigues for details. |
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@param tvec Translation vector. |
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@param cameraMatrix Camera matrix \f$A = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$ . |
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@param distCoeffs Input vector of distortion coefficients |
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\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
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4, 5, 8, 12 or 14 elements. If the vector is empty, the zero distortion coefficients are assumed. |
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@param imagePoints Output array of image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, or |
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vector\<Point2f\> . |
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@param jacobian Optional output 2Nx(10+\<numDistCoeffs\>) jacobian matrix of derivatives of image |
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points with respect to components of the rotation vector, translation vector, focal lengths, |
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coordinates of the principal point and the distortion coefficients. In the old interface different |
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components of the jacobian are returned via different output parameters. |
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@param aspectRatio Optional "fixed aspect ratio" parameter. If the parameter is not 0, the |
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function assumes that the aspect ratio (*fx/fy*) is fixed and correspondingly adjusts the jacobian |
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matrix. |
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|
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The function computes projections of 3D points to the image plane given intrinsic and extrinsic |
|
camera parameters. Optionally, the function computes Jacobians - matrices of partial derivatives of |
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image points coordinates (as functions of all the input parameters) with respect to the particular |
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parameters, intrinsic and/or extrinsic. The Jacobians are used during the global optimization in |
|
calibrateCamera, solvePnP, and stereoCalibrate . The function itself can also be used to compute a |
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re-projection error given the current intrinsic and extrinsic parameters. |
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|
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@note By setting rvec=tvec=(0,0,0) or by setting cameraMatrix to a 3x3 identity matrix, or by |
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passing zero distortion coefficients, you can get various useful partial cases of the function. This |
|
means that you can compute the distorted coordinates for a sparse set of points or apply a |
|
perspective transformation (and also compute the derivatives) in the ideal zero-distortion setup. |
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*/ |
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CV_EXPORTS_W void projectPoints( InputArray objectPoints, |
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InputArray rvec, InputArray tvec, |
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InputArray cameraMatrix, InputArray distCoeffs, |
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OutputArray imagePoints, |
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OutputArray jacobian = noArray(), |
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double aspectRatio = 0 ); |
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|
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/** @example samples/cpp/tutorial_code/features2D/Homography/homography_from_camera_displacement.cpp |
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An example program about homography from the camera displacement |
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|
|
Check @ref tutorial_homography "the corresponding tutorial" for more details |
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*/ |
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|
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/** @brief Finds an object pose from 3D-2D point correspondences. |
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@param objectPoints Array of object points in the object coordinate space, Nx3 1-channel or |
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1xN/Nx1 3-channel, where N is the number of points. vector\<Point3f\> can be also passed here. |
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@param imagePoints Array of corresponding image points, Nx2 1-channel or 1xN/Nx1 2-channel, |
|
where N is the number of points. vector\<Point2f\> can be also passed here. |
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@param cameraMatrix Input camera matrix \f$A = \vecthreethree{fx}{0}{cx}{0}{fy}{cy}{0}{0}{1}\f$ . |
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@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are |
|
assumed. |
|
@param rvec Output rotation vector (see @ref Rodrigues ) that, together with tvec , brings points from |
|
the model coordinate system to the camera coordinate system. |
|
@param tvec Output translation vector. |
|
@param useExtrinsicGuess Parameter used for #SOLVEPNP_ITERATIVE. If true (1), the function uses |
|
the provided rvec and tvec values as initial approximations of the rotation and translation |
|
vectors, respectively, and further optimizes them. |
|
@param flags Method for solving a PnP problem: |
|
- **SOLVEPNP_ITERATIVE** Iterative method is based on Levenberg-Marquardt optimization. In |
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this case the function finds such a pose that minimizes reprojection error, that is the sum |
|
of squared distances between the observed projections imagePoints and the projected (using |
|
projectPoints ) objectPoints . |
|
- **SOLVEPNP_P3P** Method is based on the paper of X.S. Gao, X.-R. Hou, J. Tang, H.-F. Chang |
|
"Complete Solution Classification for the Perspective-Three-Point Problem" (@cite gao2003complete). |
|
In this case the function requires exactly four object and image points. |
|
- **SOLVEPNP_AP3P** Method is based on the paper of T. Ke, S. Roumeliotis |
|
"An Efficient Algebraic Solution to the Perspective-Three-Point Problem" (@cite Ke17). |
|
In this case the function requires exactly four object and image points. |
|
- **SOLVEPNP_EPNP** Method has been introduced by F.Moreno-Noguer, V.Lepetit and P.Fua in the |
|
paper "EPnP: Efficient Perspective-n-Point Camera Pose Estimation" (@cite lepetit2009epnp). |
|
- **SOLVEPNP_DLS** Method is based on the paper of Joel A. Hesch and Stergios I. Roumeliotis. |
|
"A Direct Least-Squares (DLS) Method for PnP" (@cite hesch2011direct). |
|
- **SOLVEPNP_UPNP** Method is based on the paper of A.Penate-Sanchez, J.Andrade-Cetto, |
|
F.Moreno-Noguer. "Exhaustive Linearization for Robust Camera Pose and Focal Length |
|
Estimation" (@cite penate2013exhaustive). In this case the function also estimates the parameters \f$f_x\f$ and \f$f_y\f$ |
|
assuming that both have the same value. Then the cameraMatrix is updated with the estimated |
|
focal length. |
|
- **SOLVEPNP_AP3P** Method is based on the paper of Tong Ke and Stergios I. Roumeliotis. |
|
"An Efficient Algebraic Solution to the Perspective-Three-Point Problem" (@cite Ke17). In this case the |
|
function requires exactly four object and image points. |
|
|
|
The function estimates the object pose given a set of object points, their corresponding image |
|
projections, as well as the camera matrix and the distortion coefficients, see the figure below |
|
(more precisely, the X-axis of the camera frame is pointing to the right, the Y-axis downward |
|
and the Z-axis forward). |
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|
|
![](pnp.jpg) |
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Points expressed in the world frame \f$ \bf{X}_w \f$ are projected into the image plane \f$ \left[ u, v \right] \f$ |
|
using the perspective projection model \f$ \Pi \f$ and the camera intrinsic parameters matrix \f$ \bf{A} \f$: |
|
|
|
\f[ |
|
\begin{align*} |
|
\begin{bmatrix} |
|
u \\ |
|
v \\ |
|
1 |
|
\end{bmatrix} &= |
|
\bf{A} \hspace{0.1em} \Pi \hspace{0.2em} ^{c}\bf{M}_w |
|
\begin{bmatrix} |
|
X_{w} \\ |
|
Y_{w} \\ |
|
Z_{w} \\ |
|
1 |
|
\end{bmatrix} \\ |
|
\begin{bmatrix} |
|
u \\ |
|
v \\ |
|
1 |
|
\end{bmatrix} &= |
|
\begin{bmatrix} |
|
f_x & 0 & c_x \\ |
|
0 & f_y & c_y \\ |
|
0 & 0 & 1 |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
1 & 0 & 0 & 0 \\ |
|
0 & 1 & 0 & 0 \\ |
|
0 & 0 & 1 & 0 |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
r_{11} & r_{12} & r_{13} & t_x \\ |
|
r_{21} & r_{22} & r_{23} & t_y \\ |
|
r_{31} & r_{32} & r_{33} & t_z \\ |
|
0 & 0 & 0 & 1 |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
X_{w} \\ |
|
Y_{w} \\ |
|
Z_{w} \\ |
|
1 |
|
\end{bmatrix} |
|
\end{align*} |
|
\f] |
|
|
|
The estimated pose is thus the rotation (`rvec`) and the translation (`tvec`) vectors that allow to transform |
|
a 3D point expressed in the world frame into the camera frame: |
|
|
|
\f[ |
|
\begin{align*} |
|
\begin{bmatrix} |
|
X_c \\ |
|
Y_c \\ |
|
Z_c \\ |
|
1 |
|
\end{bmatrix} &= |
|
\hspace{0.2em} ^{c}\bf{M}_w |
|
\begin{bmatrix} |
|
X_{w} \\ |
|
Y_{w} \\ |
|
Z_{w} \\ |
|
1 |
|
\end{bmatrix} \\ |
|
\begin{bmatrix} |
|
X_c \\ |
|
Y_c \\ |
|
Z_c \\ |
|
1 |
|
\end{bmatrix} &= |
|
\begin{bmatrix} |
|
r_{11} & r_{12} & r_{13} & t_x \\ |
|
r_{21} & r_{22} & r_{23} & t_y \\ |
|
r_{31} & r_{32} & r_{33} & t_z \\ |
|
0 & 0 & 0 & 1 |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
X_{w} \\ |
|
Y_{w} \\ |
|
Z_{w} \\ |
|
1 |
|
\end{bmatrix} |
|
\end{align*} |
|
\f] |
|
|
|
@note |
|
- An example of how to use solvePnP for planar augmented reality can be found at |
|
opencv_source_code/samples/python/plane_ar.py |
|
- If you are using Python: |
|
- Numpy array slices won't work as input because solvePnP requires contiguous |
|
arrays (enforced by the assertion using cv::Mat::checkVector() around line 55 of |
|
modules/calib3d/src/solvepnp.cpp version 2.4.9) |
|
- The P3P algorithm requires image points to be in an array of shape (N,1,2) due |
|
to its calling of cv::undistortPoints (around line 75 of modules/calib3d/src/solvepnp.cpp version 2.4.9) |
|
which requires 2-channel information. |
|
- Thus, given some data D = np.array(...) where D.shape = (N,M), in order to use a subset of |
|
it as, e.g., imagePoints, one must effectively copy it into a new array: imagePoints = |
|
np.ascontiguousarray(D[:,:2]).reshape((N,1,2)) |
|
- The methods **SOLVEPNP_DLS** and **SOLVEPNP_UPNP** cannot be used as the current implementations are |
|
unstable and sometimes give completely wrong results. If you pass one of these two |
|
flags, **SOLVEPNP_EPNP** method will be used instead. |
|
- The minimum number of points is 4 in the general case. In the case of **SOLVEPNP_P3P** and **SOLVEPNP_AP3P** |
|
methods, it is required to use exactly 4 points (the first 3 points are used to estimate all the solutions |
|
of the P3P problem, the last one is used to retain the best solution that minimizes the reprojection error). |
|
- With **SOLVEPNP_ITERATIVE** method and `useExtrinsicGuess=true`, the minimum number of points is 3 (3 points |
|
are sufficient to compute a pose but there are up to 4 solutions). The initial solution should be close to the |
|
global solution to converge. |
|
*/ |
|
CV_EXPORTS_W bool solvePnP( InputArray objectPoints, InputArray imagePoints, |
|
InputArray cameraMatrix, InputArray distCoeffs, |
|
OutputArray rvec, OutputArray tvec, |
|
bool useExtrinsicGuess = false, int flags = SOLVEPNP_ITERATIVE ); |
|
|
|
/** @brief Finds an object pose from 3D-2D point correspondences using the RANSAC scheme. |
|
|
|
@param objectPoints Array of object points in the object coordinate space, Nx3 1-channel or |
|
1xN/Nx1 3-channel, where N is the number of points. vector\<Point3f\> can be also passed here. |
|
@param imagePoints Array of corresponding image points, Nx2 1-channel or 1xN/Nx1 2-channel, |
|
where N is the number of points. vector\<Point2f\> can be also passed here. |
|
@param cameraMatrix Input camera matrix \f$A = \vecthreethree{fx}{0}{cx}{0}{fy}{cy}{0}{0}{1}\f$ . |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are |
|
assumed. |
|
@param rvec Output rotation vector (see Rodrigues ) that, together with tvec , brings points from |
|
the model coordinate system to the camera coordinate system. |
|
@param tvec Output translation vector. |
|
@param useExtrinsicGuess Parameter used for SOLVEPNP_ITERATIVE. If true (1), the function uses |
|
the provided rvec and tvec values as initial approximations of the rotation and translation |
|
vectors, respectively, and further optimizes them. |
|
@param iterationsCount Number of iterations. |
|
@param reprojectionError Inlier threshold value used by the RANSAC procedure. The parameter value |
|
is the maximum allowed distance between the observed and computed point projections to consider it |
|
an inlier. |
|
@param confidence The probability that the algorithm produces a useful result. |
|
@param inliers Output vector that contains indices of inliers in objectPoints and imagePoints . |
|
@param flags Method for solving a PnP problem (see solvePnP ). |
|
|
|
The function estimates an object pose given a set of object points, their corresponding image |
|
projections, as well as the camera matrix and the distortion coefficients. This function finds such |
|
a pose that minimizes reprojection error, that is, the sum of squared distances between the observed |
|
projections imagePoints and the projected (using projectPoints ) objectPoints. The use of RANSAC |
|
makes the function resistant to outliers. |
|
|
|
@note |
|
- An example of how to use solvePNPRansac for object detection can be found at |
|
opencv_source_code/samples/cpp/tutorial_code/calib3d/real_time_pose_estimation/ |
|
- The default method used to estimate the camera pose for the Minimal Sample Sets step |
|
is #SOLVEPNP_EPNP. Exceptions are: |
|
- if you choose #SOLVEPNP_P3P or #SOLVEPNP_AP3P, these methods will be used. |
|
- if the number of input points is equal to 4, #SOLVEPNP_P3P is used. |
|
- The method used to estimate the camera pose using all the inliers is defined by the |
|
flags parameters unless it is equal to #SOLVEPNP_P3P or #SOLVEPNP_AP3P. In this case, |
|
the method #SOLVEPNP_EPNP will be used instead. |
|
*/ |
|
CV_EXPORTS_W bool solvePnPRansac( InputArray objectPoints, InputArray imagePoints, |
|
InputArray cameraMatrix, InputArray distCoeffs, |
|
OutputArray rvec, OutputArray tvec, |
|
bool useExtrinsicGuess = false, int iterationsCount = 100, |
|
float reprojectionError = 8.0, double confidence = 0.99, |
|
OutputArray inliers = noArray(), int flags = SOLVEPNP_ITERATIVE ); |
|
/** @brief Finds an object pose from 3 3D-2D point correspondences. |
|
|
|
@param objectPoints Array of object points in the object coordinate space, 3x3 1-channel or |
|
1x3/3x1 3-channel. vector\<Point3f\> can be also passed here. |
|
@param imagePoints Array of corresponding image points, 3x2 1-channel or 1x3/3x1 2-channel. |
|
vector\<Point2f\> can be also passed here. |
|
@param cameraMatrix Input camera matrix \f$A = \vecthreethree{fx}{0}{cx}{0}{fy}{cy}{0}{0}{1}\f$ . |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are |
|
assumed. |
|
@param rvecs Output rotation vectors (see Rodrigues ) that, together with tvecs , brings points from |
|
the model coordinate system to the camera coordinate system. A P3P problem has up to 4 solutions. |
|
@param tvecs Output translation vectors. |
|
@param flags Method for solving a P3P problem: |
|
- **SOLVEPNP_P3P** Method is based on the paper of X.S. Gao, X.-R. Hou, J. Tang, H.-F. Chang |
|
"Complete Solution Classification for the Perspective-Three-Point Problem" (@cite gao2003complete). |
|
- **SOLVEPNP_AP3P** Method is based on the paper of Tong Ke and Stergios I. Roumeliotis. |
|
"An Efficient Algebraic Solution to the Perspective-Three-Point Problem" (@cite Ke17). |
|
|
|
The function estimates the object pose given 3 object points, their corresponding image |
|
projections, as well as the camera matrix and the distortion coefficients. |
|
*/ |
|
CV_EXPORTS_W int solveP3P( InputArray objectPoints, InputArray imagePoints, |
|
InputArray cameraMatrix, InputArray distCoeffs, |
|
OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, |
|
int flags ); |
|
|
|
/** @brief Finds an initial camera matrix from 3D-2D point correspondences. |
|
|
|
@param objectPoints Vector of vectors of the calibration pattern points in the calibration pattern |
|
coordinate space. In the old interface all the per-view vectors are concatenated. See |
|
calibrateCamera for details. |
|
@param imagePoints Vector of vectors of the projections of the calibration pattern points. In the |
|
old interface all the per-view vectors are concatenated. |
|
@param imageSize Image size in pixels used to initialize the principal point. |
|
@param aspectRatio If it is zero or negative, both \f$f_x\f$ and \f$f_y\f$ are estimated independently. |
|
Otherwise, \f$f_x = f_y * \texttt{aspectRatio}\f$ . |
|
|
|
The function estimates and returns an initial camera matrix for the camera calibration process. |
|
Currently, the function only supports planar calibration patterns, which are patterns where each |
|
object point has z-coordinate =0. |
|
*/ |
|
CV_EXPORTS_W Mat initCameraMatrix2D( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints, |
|
Size imageSize, double aspectRatio = 1.0 ); |
|
|
|
/** @brief Finds the positions of internal corners of the chessboard. |
|
|
|
@param image Source chessboard view. It must be an 8-bit grayscale or color image. |
|
@param patternSize Number of inner corners per a chessboard row and column |
|
( patternSize = cv::Size(points_per_row,points_per_colum) = cv::Size(columns,rows) ). |
|
@param corners Output array of detected corners. |
|
@param flags Various operation flags that can be zero or a combination of the following values: |
|
- **CALIB_CB_ADAPTIVE_THRESH** Use adaptive thresholding to convert the image to black |
|
and white, rather than a fixed threshold level (computed from the average image brightness). |
|
- **CALIB_CB_NORMALIZE_IMAGE** Normalize the image gamma with equalizeHist before |
|
applying fixed or adaptive thresholding. |
|
- **CALIB_CB_FILTER_QUADS** Use additional criteria (like contour area, perimeter, |
|
square-like shape) to filter out false quads extracted at the contour retrieval stage. |
|
- **CALIB_CB_FAST_CHECK** Run a fast check on the image that looks for chessboard corners, |
|
and shortcut the call if none is found. This can drastically speed up the call in the |
|
degenerate condition when no chessboard is observed. |
|
|
|
The function attempts to determine whether the input image is a view of the chessboard pattern and |
|
locate the internal chessboard corners. The function returns a non-zero value if all of the corners |
|
are found and they are placed in a certain order (row by row, left to right in every row). |
|
Otherwise, if the function fails to find all the corners or reorder them, it returns 0. For example, |
|
a regular chessboard has 8 x 8 squares and 7 x 7 internal corners, that is, points where the black |
|
squares touch each other. The detected coordinates are approximate, and to determine their positions |
|
more accurately, the function calls cornerSubPix. You also may use the function cornerSubPix with |
|
different parameters if returned coordinates are not accurate enough. |
|
|
|
Sample usage of detecting and drawing chessboard corners: : |
|
@code |
|
Size patternsize(8,6); //interior number of corners |
|
Mat gray = ....; //source image |
|
vector<Point2f> corners; //this will be filled by the detected corners |
|
|
|
//CALIB_CB_FAST_CHECK saves a lot of time on images |
|
//that do not contain any chessboard corners |
|
bool patternfound = findChessboardCorners(gray, patternsize, corners, |
|
CALIB_CB_ADAPTIVE_THRESH + CALIB_CB_NORMALIZE_IMAGE |
|
+ CALIB_CB_FAST_CHECK); |
|
|
|
if(patternfound) |
|
cornerSubPix(gray, corners, Size(11, 11), Size(-1, -1), |
|
TermCriteria(CV_TERMCRIT_EPS + CV_TERMCRIT_ITER, 30, 0.1)); |
|
|
|
drawChessboardCorners(img, patternsize, Mat(corners), patternfound); |
|
@endcode |
|
@note The function requires white space (like a square-thick border, the wider the better) around |
|
the board to make the detection more robust in various environments. Otherwise, if there is no |
|
border and the background is dark, the outer black squares cannot be segmented properly and so the |
|
square grouping and ordering algorithm fails. |
|
*/ |
|
CV_EXPORTS_W bool findChessboardCorners( InputArray image, Size patternSize, OutputArray corners, |
|
int flags = CALIB_CB_ADAPTIVE_THRESH + CALIB_CB_NORMALIZE_IMAGE ); |
|
|
|
/** @brief Finds the positions of internal corners of the chessboard using a sector based approach. |
|
|
|
@param image Source chessboard view. It must be an 8-bit grayscale or color image. |
|
@param patternSize Number of inner corners per a chessboard row and column |
|
( patternSize = cv::Size(points_per_row,points_per_colum) = cv::Size(columns,rows) ). |
|
@param corners Output array of detected corners. |
|
@param flags Various operation flags that can be zero or a combination of the following values: |
|
- **CALIB_CB_NORMALIZE_IMAGE** Normalize the image gamma with equalizeHist before detection. |
|
- **CALIB_CB_EXHAUSTIVE ** Run an exhaustive search to improve detection rate. |
|
- **CALIB_CB_ACCURACY ** Up sample input image to improve sub-pixel accuracy due to aliasing effects. |
|
This should be used if an accurate camera calibration is required. |
|
|
|
The function is analog to findchessboardCorners but uses a localized radon |
|
transformation approximated by box filters being more robust to all sort of |
|
noise, faster on larger images and is able to directly return the sub-pixel |
|
position of the internal chessboard corners. The Method is based on the paper |
|
@cite duda2018 "Accurate Detection and Localization of Checkerboard Corners for |
|
Calibration" demonstrating that the returned sub-pixel positions are more |
|
accurate than the one returned by cornerSubPix allowing a precise camera |
|
calibration for demanding applications. |
|
|
|
@note The function requires a white boarder with roughly the same width as one |
|
of the checkerboard fields around the whole board to improve the detection in |
|
various environments. In addition, because of the localized radon |
|
transformation it is beneficial to use round corners for the field corners |
|
which are located on the outside of the board. The following figure illustrates |
|
a sample checkerboard optimized for the detection. However, any other checkerboard |
|
can be used as well. |
|
![Checkerboard](pics/checkerboard_radon.png) |
|
*/ |
|
CV_EXPORTS_W bool findChessboardCornersSB(InputArray image,Size patternSize, OutputArray corners,int flags=0); |
|
|
|
//! finds subpixel-accurate positions of the chessboard corners |
|
CV_EXPORTS bool find4QuadCornerSubpix( InputArray img, InputOutputArray corners, Size region_size ); |
|
|
|
/** @brief Renders the detected chessboard corners. |
|
|
|
@param image Destination image. It must be an 8-bit color image. |
|
@param patternSize Number of inner corners per a chessboard row and column |
|
(patternSize = cv::Size(points_per_row,points_per_column)). |
|
@param corners Array of detected corners, the output of findChessboardCorners. |
|
@param patternWasFound Parameter indicating whether the complete board was found or not. The |
|
return value of findChessboardCorners should be passed here. |
|
|
|
The function draws individual chessboard corners detected either as red circles if the board was not |
|
found, or as colored corners connected with lines if the board was found. |
|
*/ |
|
CV_EXPORTS_W void drawChessboardCorners( InputOutputArray image, Size patternSize, |
|
InputArray corners, bool patternWasFound ); |
|
|
|
struct CV_EXPORTS_W_SIMPLE CirclesGridFinderParameters |
|
{ |
|
CV_WRAP CirclesGridFinderParameters(); |
|
CV_PROP_RW cv::Size2f densityNeighborhoodSize; |
|
CV_PROP_RW float minDensity; |
|
CV_PROP_RW int kmeansAttempts; |
|
CV_PROP_RW int minDistanceToAddKeypoint; |
|
CV_PROP_RW int keypointScale; |
|
CV_PROP_RW float minGraphConfidence; |
|
CV_PROP_RW float vertexGain; |
|
CV_PROP_RW float vertexPenalty; |
|
CV_PROP_RW float existingVertexGain; |
|
CV_PROP_RW float edgeGain; |
|
CV_PROP_RW float edgePenalty; |
|
CV_PROP_RW float convexHullFactor; |
|
CV_PROP_RW float minRNGEdgeSwitchDist; |
|
|
|
enum GridType |
|
{ |
|
SYMMETRIC_GRID, ASYMMETRIC_GRID |
|
}; |
|
GridType gridType; |
|
|
|
CV_PROP_RW float squareSize; //!< Distance between two adjacent points. Used by CALIB_CB_CLUSTERING. |
|
CV_PROP_RW float maxRectifiedDistance; //!< Max deviation from predicion. Used by CALIB_CB_CLUSTERING. |
|
}; |
|
|
|
#ifndef DISABLE_OPENCV_3_COMPATIBILITY |
|
typedef CirclesGridFinderParameters CirclesGridFinderParameters2; |
|
#endif |
|
|
|
/** @brief Finds centers in the grid of circles. |
|
|
|
@param image grid view of input circles; it must be an 8-bit grayscale or color image. |
|
@param patternSize number of circles per row and column |
|
( patternSize = Size(points_per_row, points_per_colum) ). |
|
@param centers output array of detected centers. |
|
@param flags various operation flags that can be one of the following values: |
|
- **CALIB_CB_SYMMETRIC_GRID** uses symmetric pattern of circles. |
|
- **CALIB_CB_ASYMMETRIC_GRID** uses asymmetric pattern of circles. |
|
- **CALIB_CB_CLUSTERING** uses a special algorithm for grid detection. It is more robust to |
|
perspective distortions but much more sensitive to background clutter. |
|
@param blobDetector feature detector that finds blobs like dark circles on light background. |
|
@param parameters struct for finding circles in a grid pattern. |
|
|
|
The function attempts to determine whether the input image contains a grid of circles. If it is, the |
|
function locates centers of the circles. The function returns a non-zero value if all of the centers |
|
have been found and they have been placed in a certain order (row by row, left to right in every |
|
row). Otherwise, if the function fails to find all the corners or reorder them, it returns 0. |
|
|
|
Sample usage of detecting and drawing the centers of circles: : |
|
@code |
|
Size patternsize(7,7); //number of centers |
|
Mat gray = ....; //source image |
|
vector<Point2f> centers; //this will be filled by the detected centers |
|
|
|
bool patternfound = findCirclesGrid(gray, patternsize, centers); |
|
|
|
drawChessboardCorners(img, patternsize, Mat(centers), patternfound); |
|
@endcode |
|
@note The function requires white space (like a square-thick border, the wider the better) around |
|
the board to make the detection more robust in various environments. |
|
*/ |
|
CV_EXPORTS_W bool findCirclesGrid( InputArray image, Size patternSize, |
|
OutputArray centers, int flags, |
|
const Ptr<FeatureDetector> &blobDetector, |
|
const CirclesGridFinderParameters& parameters); |
|
|
|
/** @overload */ |
|
CV_EXPORTS_W bool findCirclesGrid( InputArray image, Size patternSize, |
|
OutputArray centers, int flags = CALIB_CB_SYMMETRIC_GRID, |
|
const Ptr<FeatureDetector> &blobDetector = SimpleBlobDetector::create()); |
|
|
|
/** @brief Finds the camera intrinsic and extrinsic parameters from several views of a calibration pattern. |
|
|
|
@param objectPoints In the new interface it is a vector of vectors of calibration pattern points in |
|
the calibration pattern coordinate space (e.g. std::vector<std::vector<cv::Vec3f>>). The outer |
|
vector contains as many elements as the number of the pattern views. If the same calibration pattern |
|
is shown in each view and it is fully visible, all the vectors will be the same. Although, it is |
|
possible to use partially occluded patterns, or even different patterns in different views. Then, |
|
the vectors will be different. The points are 3D, but since they are in a pattern coordinate system, |
|
then, if the rig is planar, it may make sense to put the model to a XY coordinate plane so that |
|
Z-coordinate of each input object point is 0. |
|
In the old interface all the vectors of object points from different views are concatenated |
|
together. |
|
@param imagePoints In the new interface it is a vector of vectors of the projections of calibration |
|
pattern points (e.g. std::vector<std::vector<cv::Vec2f>>). imagePoints.size() and |
|
objectPoints.size() and imagePoints[i].size() must be equal to objectPoints[i].size() for each i. |
|
In the old interface all the vectors of object points from different views are concatenated |
|
together. |
|
@param imageSize Size of the image used only to initialize the intrinsic camera matrix. |
|
@param cameraMatrix Output 3x3 floating-point camera matrix |
|
\f$A = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . If CV\_CALIB\_USE\_INTRINSIC\_GUESS |
|
and/or CALIB_FIX_ASPECT_RATIO are specified, some or all of fx, fy, cx, cy must be |
|
initialized before calling the function. |
|
@param distCoeffs Output vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. |
|
@param rvecs Output vector of rotation vectors (see Rodrigues ) estimated for each pattern view |
|
(e.g. std::vector<cv::Mat>>). That is, each k-th rotation vector together with the corresponding |
|
k-th translation vector (see the next output parameter description) brings the calibration pattern |
|
from the model coordinate space (in which object points are specified) to the world coordinate |
|
space, that is, a real position of the calibration pattern in the k-th pattern view (k=0.. *M* -1). |
|
@param tvecs Output vector of translation vectors estimated for each pattern view. |
|
@param stdDeviationsIntrinsics Output vector of standard deviations estimated for intrinsic parameters. |
|
Order of deviations values: |
|
\f$(f_x, f_y, c_x, c_y, k_1, k_2, p_1, p_2, k_3, k_4, k_5, k_6 , s_1, s_2, s_3, |
|
s_4, \tau_x, \tau_y)\f$ If one of parameters is not estimated, it's deviation is equals to zero. |
|
@param stdDeviationsExtrinsics Output vector of standard deviations estimated for extrinsic parameters. |
|
Order of deviations values: \f$(R_1, T_1, \dotsc , R_M, T_M)\f$ where M is number of pattern views, |
|
\f$R_i, T_i\f$ are concatenated 1x3 vectors. |
|
@param perViewErrors Output vector of the RMS re-projection error estimated for each pattern view. |
|
@param flags Different flags that may be zero or a combination of the following values: |
|
- **CALIB_USE_INTRINSIC_GUESS** cameraMatrix contains valid initial values of |
|
fx, fy, cx, cy that are optimized further. Otherwise, (cx, cy) is initially set to the image |
|
center ( imageSize is used), and focal distances are computed in a least-squares fashion. |
|
Note, that if intrinsic parameters are known, there is no need to use this function just to |
|
estimate extrinsic parameters. Use solvePnP instead. |
|
- **CALIB_FIX_PRINCIPAL_POINT** The principal point is not changed during the global |
|
optimization. It stays at the center or at a different location specified when |
|
CALIB_USE_INTRINSIC_GUESS is set too. |
|
- **CALIB_FIX_ASPECT_RATIO** The functions considers only fy as a free parameter. The |
|
ratio fx/fy stays the same as in the input cameraMatrix . When |
|
CALIB_USE_INTRINSIC_GUESS is not set, the actual input values of fx and fy are |
|
ignored, only their ratio is computed and used further. |
|
- **CALIB_ZERO_TANGENT_DIST** Tangential distortion coefficients \f$(p_1, p_2)\f$ are set |
|
to zeros and stay zero. |
|
- **CALIB_FIX_K1,...,CALIB_FIX_K6** The corresponding radial distortion |
|
coefficient is not changed during the optimization. If CALIB_USE_INTRINSIC_GUESS is |
|
set, the coefficient from the supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
- **CALIB_RATIONAL_MODEL** Coefficients k4, k5, and k6 are enabled. To provide the |
|
backward compatibility, this extra flag should be explicitly specified to make the |
|
calibration function use the rational model and return 8 coefficients. If the flag is not |
|
set, the function computes and returns only 5 distortion coefficients. |
|
- **CALIB_THIN_PRISM_MODEL** Coefficients s1, s2, s3 and s4 are enabled. To provide the |
|
backward compatibility, this extra flag should be explicitly specified to make the |
|
calibration function use the thin prism model and return 12 coefficients. If the flag is not |
|
set, the function computes and returns only 5 distortion coefficients. |
|
- **CALIB_FIX_S1_S2_S3_S4** The thin prism distortion coefficients are not changed during |
|
the optimization. If CALIB_USE_INTRINSIC_GUESS is set, the coefficient from the |
|
supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
- **CALIB_TILTED_MODEL** Coefficients tauX and tauY are enabled. To provide the |
|
backward compatibility, this extra flag should be explicitly specified to make the |
|
calibration function use the tilted sensor model and return 14 coefficients. If the flag is not |
|
set, the function computes and returns only 5 distortion coefficients. |
|
- **CALIB_FIX_TAUX_TAUY** The coefficients of the tilted sensor model are not changed during |
|
the optimization. If CALIB_USE_INTRINSIC_GUESS is set, the coefficient from the |
|
supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
@param criteria Termination criteria for the iterative optimization algorithm. |
|
|
|
@return the overall RMS re-projection error. |
|
|
|
The function estimates the intrinsic camera parameters and extrinsic parameters for each of the |
|
views. The algorithm is based on @cite Zhang2000 and @cite BouguetMCT . The coordinates of 3D object |
|
points and their corresponding 2D projections in each view must be specified. That may be achieved |
|
by using an object with a known geometry and easily detectable feature points. Such an object is |
|
called a calibration rig or calibration pattern, and OpenCV has built-in support for a chessboard as |
|
a calibration rig (see findChessboardCorners ). Currently, initialization of intrinsic parameters |
|
(when CALIB_USE_INTRINSIC_GUESS is not set) is only implemented for planar calibration |
|
patterns (where Z-coordinates of the object points must be all zeros). 3D calibration rigs can also |
|
be used as long as initial cameraMatrix is provided. |
|
|
|
The algorithm performs the following steps: |
|
|
|
- Compute the initial intrinsic parameters (the option only available for planar calibration |
|
patterns) or read them from the input parameters. The distortion coefficients are all set to |
|
zeros initially unless some of CALIB_FIX_K? are specified. |
|
|
|
- Estimate the initial camera pose as if the intrinsic parameters have been already known. This is |
|
done using solvePnP . |
|
|
|
- Run the global Levenberg-Marquardt optimization algorithm to minimize the reprojection error, |
|
that is, the total sum of squared distances between the observed feature points imagePoints and |
|
the projected (using the current estimates for camera parameters and the poses) object points |
|
objectPoints. See projectPoints for details. |
|
|
|
@note |
|
If you use a non-square (=non-NxN) grid and findChessboardCorners for calibration, and |
|
calibrateCamera returns bad values (zero distortion coefficients, an image center very far from |
|
(w/2-0.5,h/2-0.5), and/or large differences between \f$f_x\f$ and \f$f_y\f$ (ratios of 10:1 or more)), |
|
then you have probably used patternSize=cvSize(rows,cols) instead of using |
|
patternSize=cvSize(cols,rows) in findChessboardCorners . |
|
|
|
@sa |
|
calibrateCameraRO, findChessboardCorners, solvePnP, initCameraMatrix2D, stereoCalibrate, undistort |
|
*/ |
|
CV_EXPORTS_AS(calibrateCameraExtended) double calibrateCamera( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints, Size imageSize, |
|
InputOutputArray cameraMatrix, InputOutputArray distCoeffs, |
|
OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, |
|
OutputArray stdDeviationsIntrinsics, |
|
OutputArray stdDeviationsExtrinsics, |
|
OutputArray perViewErrors, |
|
int flags = 0, TermCriteria criteria = TermCriteria( |
|
TermCriteria::COUNT + TermCriteria::EPS, 30, DBL_EPSILON) ); |
|
|
|
/** @overload */ |
|
CV_EXPORTS_W double calibrateCamera( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints, Size imageSize, |
|
InputOutputArray cameraMatrix, InputOutputArray distCoeffs, |
|
OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, |
|
int flags = 0, TermCriteria criteria = TermCriteria( |
|
TermCriteria::COUNT + TermCriteria::EPS, 30, DBL_EPSILON) ); |
|
|
|
/** @brief Finds the camera intrinsic and extrinsic parameters from several views of a calibration pattern. |
|
|
|
This function is an extension of calibrateCamera() with the method of releasing object which was |
|
proposed in @cite strobl2011iccv. In many common cases with inaccurate, unmeasured, roughly planar |
|
targets (calibration plates), this method can dramatically improve the precision of the estimated |
|
camera parameters. Both the object-releasing method and standard method are supported by this |
|
function. Use the parameter **iFixedPoint** for method selection. In the internal implementation, |
|
calibrateCamera() is a wrapper for this function. |
|
|
|
@param objectPoints Vector of vectors of calibration pattern points in the calibration pattern |
|
coordinate space. See calibrateCamera() for details. If the method of releasing object to be used, |
|
the identical calibration board must be used in each view and it must be fully visible, and all |
|
objectPoints[i] must be the same and all points should be roughly close to a plane. **The calibration |
|
target has to be rigid, or at least static if the camera (rather than the calibration target) is |
|
shifted for grabbing images.** |
|
@param imagePoints Vector of vectors of the projections of calibration pattern points. See |
|
calibrateCamera() for details. |
|
@param imageSize Size of the image used only to initialize the intrinsic camera matrix. |
|
@param iFixedPoint The index of the 3D object point in objectPoints[0] to be fixed. It also acts as |
|
a switch for calibration method selection. If object-releasing method to be used, pass in the |
|
parameter in the range of [1, objectPoints[0].size()-2], otherwise a value out of this range will |
|
make standard calibration method selected. Usually the top-right corner point of the calibration |
|
board grid is recommended to be fixed when object-releasing method being utilized. According to |
|
\cite strobl2011iccv, two other points are also fixed. In this implementation, objectPoints[0].front |
|
and objectPoints[0].back.z are used. With object-releasing method, accurate rvecs, tvecs and |
|
newObjPoints are only possible if coordinates of these three fixed points are accurate enough. |
|
@param cameraMatrix Output 3x3 floating-point camera matrix. See calibrateCamera() for details. |
|
@param distCoeffs Output vector of distortion coefficients. See calibrateCamera() for details. |
|
@param rvecs Output vector of rotation vectors estimated for each pattern view. See calibrateCamera() |
|
for details. |
|
@param tvecs Output vector of translation vectors estimated for each pattern view. |
|
@param newObjPoints The updated output vector of calibration pattern points. The coordinates might |
|
be scaled based on three fixed points. The returned coordinates are accurate only if the above |
|
mentioned three fixed points are accurate. If not needed, noArray() can be passed in. This parameter |
|
is ignored with standard calibration method. |
|
@param stdDeviationsIntrinsics Output vector of standard deviations estimated for intrinsic parameters. |
|
See calibrateCamera() for details. |
|
@param stdDeviationsExtrinsics Output vector of standard deviations estimated for extrinsic parameters. |
|
See calibrateCamera() for details. |
|
@param stdDeviationsObjPoints Output vector of standard deviations estimated for refined coordinates |
|
of calibration pattern points. It has the same size and order as objectPoints[0] vector. This |
|
parameter is ignored with standard calibration method. |
|
@param perViewErrors Output vector of the RMS re-projection error estimated for each pattern view. |
|
@param flags Different flags that may be zero or a combination of some predefined values. See |
|
calibrateCamera() for details. If the method of releasing object is used, the calibration time may |
|
be much longer. CALIB_USE_QR or CALIB_USE_LU could be used for faster calibration with potentially |
|
less precise and less stable in some rare cases. |
|
@param criteria Termination criteria for the iterative optimization algorithm. |
|
|
|
@return the overall RMS re-projection error. |
|
|
|
The function estimates the intrinsic camera parameters and extrinsic parameters for each of the |
|
views. The algorithm is based on @cite Zhang2000, @cite BouguetMCT and @cite strobl2011iccv. See |
|
calibrateCamera() for other detailed explanations. |
|
@sa |
|
calibrateCamera, findChessboardCorners, solvePnP, initCameraMatrix2D, stereoCalibrate, undistort |
|
*/ |
|
CV_EXPORTS_AS(calibrateCameraROExtended) double calibrateCameraRO( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints, Size imageSize, int iFixedPoint, |
|
InputOutputArray cameraMatrix, InputOutputArray distCoeffs, |
|
OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, |
|
OutputArray newObjPoints, |
|
OutputArray stdDeviationsIntrinsics, |
|
OutputArray stdDeviationsExtrinsics, |
|
OutputArray stdDeviationsObjPoints, |
|
OutputArray perViewErrors, |
|
int flags = 0, TermCriteria criteria = TermCriteria( |
|
TermCriteria::COUNT + TermCriteria::EPS, 30, DBL_EPSILON) ); |
|
|
|
/** @overload */ |
|
CV_EXPORTS_W double calibrateCameraRO( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints, Size imageSize, int iFixedPoint, |
|
InputOutputArray cameraMatrix, InputOutputArray distCoeffs, |
|
OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, |
|
OutputArray newObjPoints, |
|
int flags = 0, TermCriteria criteria = TermCriteria( |
|
TermCriteria::COUNT + TermCriteria::EPS, 30, DBL_EPSILON) ); |
|
|
|
/** @brief Computes useful camera characteristics from the camera matrix. |
|
|
|
@param cameraMatrix Input camera matrix that can be estimated by calibrateCamera or |
|
stereoCalibrate . |
|
@param imageSize Input image size in pixels. |
|
@param apertureWidth Physical width in mm of the sensor. |
|
@param apertureHeight Physical height in mm of the sensor. |
|
@param fovx Output field of view in degrees along the horizontal sensor axis. |
|
@param fovy Output field of view in degrees along the vertical sensor axis. |
|
@param focalLength Focal length of the lens in mm. |
|
@param principalPoint Principal point in mm. |
|
@param aspectRatio \f$f_y/f_x\f$ |
|
|
|
The function computes various useful camera characteristics from the previously estimated camera |
|
matrix. |
|
|
|
@note |
|
Do keep in mind that the unity measure 'mm' stands for whatever unit of measure one chooses for |
|
the chessboard pitch (it can thus be any value). |
|
*/ |
|
CV_EXPORTS_W void calibrationMatrixValues( InputArray cameraMatrix, Size imageSize, |
|
double apertureWidth, double apertureHeight, |
|
CV_OUT double& fovx, CV_OUT double& fovy, |
|
CV_OUT double& focalLength, CV_OUT Point2d& principalPoint, |
|
CV_OUT double& aspectRatio ); |
|
|
|
/** @brief Calibrates the stereo camera. |
|
|
|
@param objectPoints Vector of vectors of the calibration pattern points. |
|
@param imagePoints1 Vector of vectors of the projections of the calibration pattern points, |
|
observed by the first camera. |
|
@param imagePoints2 Vector of vectors of the projections of the calibration pattern points, |
|
observed by the second camera. |
|
@param cameraMatrix1 Input/output first camera matrix: |
|
\f$\vecthreethree{f_x^{(j)}}{0}{c_x^{(j)}}{0}{f_y^{(j)}}{c_y^{(j)}}{0}{0}{1}\f$ , \f$j = 0,\, 1\f$ . If |
|
any of CALIB_USE_INTRINSIC_GUESS , CALIB_FIX_ASPECT_RATIO , |
|
CALIB_FIX_INTRINSIC , or CALIB_FIX_FOCAL_LENGTH are specified, some or all of the |
|
matrix components must be initialized. See the flags description for details. |
|
@param distCoeffs1 Input/output vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. The output vector length depends on the flags. |
|
@param cameraMatrix2 Input/output second camera matrix. The parameter is similar to cameraMatrix1 |
|
@param distCoeffs2 Input/output lens distortion coefficients for the second camera. The parameter |
|
is similar to distCoeffs1 . |
|
@param imageSize Size of the image used only to initialize intrinsic camera matrix. |
|
@param R Output rotation matrix between the 1st and the 2nd camera coordinate systems. |
|
@param T Output translation vector between the coordinate systems of the cameras. |
|
@param E Output essential matrix. |
|
@param F Output fundamental matrix. |
|
@param perViewErrors Output vector of the RMS re-projection error estimated for each pattern view. |
|
@param flags Different flags that may be zero or a combination of the following values: |
|
- **CALIB_FIX_INTRINSIC** Fix cameraMatrix? and distCoeffs? so that only R, T, E , and F |
|
matrices are estimated. |
|
- **CALIB_USE_INTRINSIC_GUESS** Optimize some or all of the intrinsic parameters |
|
according to the specified flags. Initial values are provided by the user. |
|
- **CALIB_USE_EXTRINSIC_GUESS** R, T contain valid initial values that are optimized further. |
|
Otherwise R, T are initialized to the median value of the pattern views (each dimension separately). |
|
- **CALIB_FIX_PRINCIPAL_POINT** Fix the principal points during the optimization. |
|
- **CALIB_FIX_FOCAL_LENGTH** Fix \f$f^{(j)}_x\f$ and \f$f^{(j)}_y\f$ . |
|
- **CALIB_FIX_ASPECT_RATIO** Optimize \f$f^{(j)}_y\f$ . Fix the ratio \f$f^{(j)}_x/f^{(j)}_y\f$ |
|
. |
|
- **CALIB_SAME_FOCAL_LENGTH** Enforce \f$f^{(0)}_x=f^{(1)}_x\f$ and \f$f^{(0)}_y=f^{(1)}_y\f$ . |
|
- **CALIB_ZERO_TANGENT_DIST** Set tangential distortion coefficients for each camera to |
|
zeros and fix there. |
|
- **CALIB_FIX_K1,...,CALIB_FIX_K6** Do not change the corresponding radial |
|
distortion coefficient during the optimization. If CALIB_USE_INTRINSIC_GUESS is set, |
|
the coefficient from the supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
- **CALIB_RATIONAL_MODEL** Enable coefficients k4, k5, and k6. To provide the backward |
|
compatibility, this extra flag should be explicitly specified to make the calibration |
|
function use the rational model and return 8 coefficients. If the flag is not set, the |
|
function computes and returns only 5 distortion coefficients. |
|
- **CALIB_THIN_PRISM_MODEL** Coefficients s1, s2, s3 and s4 are enabled. To provide the |
|
backward compatibility, this extra flag should be explicitly specified to make the |
|
calibration function use the thin prism model and return 12 coefficients. If the flag is not |
|
set, the function computes and returns only 5 distortion coefficients. |
|
- **CALIB_FIX_S1_S2_S3_S4** The thin prism distortion coefficients are not changed during |
|
the optimization. If CALIB_USE_INTRINSIC_GUESS is set, the coefficient from the |
|
supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
- **CALIB_TILTED_MODEL** Coefficients tauX and tauY are enabled. To provide the |
|
backward compatibility, this extra flag should be explicitly specified to make the |
|
calibration function use the tilted sensor model and return 14 coefficients. If the flag is not |
|
set, the function computes and returns only 5 distortion coefficients. |
|
- **CALIB_FIX_TAUX_TAUY** The coefficients of the tilted sensor model are not changed during |
|
the optimization. If CALIB_USE_INTRINSIC_GUESS is set, the coefficient from the |
|
supplied distCoeffs matrix is used. Otherwise, it is set to 0. |
|
@param criteria Termination criteria for the iterative optimization algorithm. |
|
|
|
The function estimates transformation between two cameras making a stereo pair. If you have a stereo |
|
camera where the relative position and orientation of two cameras is fixed, and if you computed |
|
poses of an object relative to the first camera and to the second camera, (R1, T1) and (R2, T2), |
|
respectively (this can be done with solvePnP ), then those poses definitely relate to each other. |
|
This means that, given ( \f$R_1\f$,\f$T_1\f$ ), it should be possible to compute ( \f$R_2\f$,\f$T_2\f$ ). You only |
|
need to know the position and orientation of the second camera relative to the first camera. This is |
|
what the described function does. It computes ( \f$R\f$,\f$T\f$ ) so that: |
|
|
|
\f[R_2=R*R_1\f] |
|
\f[T_2=R*T_1 + T,\f] |
|
|
|
Optionally, it computes the essential matrix E: |
|
|
|
\f[E= \vecthreethree{0}{-T_2}{T_1}{T_2}{0}{-T_0}{-T_1}{T_0}{0} *R\f] |
|
|
|
where \f$T_i\f$ are components of the translation vector \f$T\f$ : \f$T=[T_0, T_1, T_2]^T\f$ . And the function |
|
can also compute the fundamental matrix F: |
|
|
|
\f[F = cameraMatrix2^{-T} E cameraMatrix1^{-1}\f] |
|
|
|
Besides the stereo-related information, the function can also perform a full calibration of each of |
|
two cameras. However, due to the high dimensionality of the parameter space and noise in the input |
|
data, the function can diverge from the correct solution. If the intrinsic parameters can be |
|
estimated with high accuracy for each of the cameras individually (for example, using |
|
calibrateCamera ), you are recommended to do so and then pass CALIB_FIX_INTRINSIC flag to the |
|
function along with the computed intrinsic parameters. Otherwise, if all the parameters are |
|
estimated at once, it makes sense to restrict some parameters, for example, pass |
|
CALIB_SAME_FOCAL_LENGTH and CALIB_ZERO_TANGENT_DIST flags, which is usually a |
|
reasonable assumption. |
|
|
|
Similarly to calibrateCamera , the function minimizes the total re-projection error for all the |
|
points in all the available views from both cameras. The function returns the final value of the |
|
re-projection error. |
|
*/ |
|
CV_EXPORTS_AS(stereoCalibrateExtended) double stereoCalibrate( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints1, InputArrayOfArrays imagePoints2, |
|
InputOutputArray cameraMatrix1, InputOutputArray distCoeffs1, |
|
InputOutputArray cameraMatrix2, InputOutputArray distCoeffs2, |
|
Size imageSize, InputOutputArray R,InputOutputArray T, OutputArray E, OutputArray F, |
|
OutputArray perViewErrors, int flags = CALIB_FIX_INTRINSIC, |
|
TermCriteria criteria = TermCriteria(TermCriteria::COUNT+TermCriteria::EPS, 30, 1e-6) ); |
|
|
|
/// @overload |
|
CV_EXPORTS_W double stereoCalibrate( InputArrayOfArrays objectPoints, |
|
InputArrayOfArrays imagePoints1, InputArrayOfArrays imagePoints2, |
|
InputOutputArray cameraMatrix1, InputOutputArray distCoeffs1, |
|
InputOutputArray cameraMatrix2, InputOutputArray distCoeffs2, |
|
Size imageSize, OutputArray R,OutputArray T, OutputArray E, OutputArray F, |
|
int flags = CALIB_FIX_INTRINSIC, |
|
TermCriteria criteria = TermCriteria(TermCriteria::COUNT+TermCriteria::EPS, 30, 1e-6) ); |
|
|
|
/** @brief Computes rectification transforms for each head of a calibrated stereo camera. |
|
|
|
@param cameraMatrix1 First camera matrix. |
|
@param distCoeffs1 First camera distortion parameters. |
|
@param cameraMatrix2 Second camera matrix. |
|
@param distCoeffs2 Second camera distortion parameters. |
|
@param imageSize Size of the image used for stereo calibration. |
|
@param R Rotation matrix between the coordinate systems of the first and the second cameras. |
|
@param T Translation vector between coordinate systems of the cameras. |
|
@param R1 Output 3x3 rectification transform (rotation matrix) for the first camera. |
|
@param R2 Output 3x3 rectification transform (rotation matrix) for the second camera. |
|
@param P1 Output 3x4 projection matrix in the new (rectified) coordinate systems for the first |
|
camera. |
|
@param P2 Output 3x4 projection matrix in the new (rectified) coordinate systems for the second |
|
camera. |
|
@param Q Output \f$4 \times 4\f$ disparity-to-depth mapping matrix (see reprojectImageTo3D ). |
|
@param flags Operation flags that may be zero or CALIB_ZERO_DISPARITY . If the flag is set, |
|
the function makes the principal points of each camera have the same pixel coordinates in the |
|
rectified views. And if the flag is not set, the function may still shift the images in the |
|
horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the |
|
useful image area. |
|
@param alpha Free scaling parameter. If it is -1 or absent, the function performs the default |
|
scaling. Otherwise, the parameter should be between 0 and 1. alpha=0 means that the rectified |
|
images are zoomed and shifted so that only valid pixels are visible (no black areas after |
|
rectification). alpha=1 means that the rectified image is decimated and shifted so that all the |
|
pixels from the original images from the cameras are retained in the rectified images (no source |
|
image pixels are lost). Obviously, any intermediate value yields an intermediate result between |
|
those two extreme cases. |
|
@param newImageSize New image resolution after rectification. The same size should be passed to |
|
initUndistortRectifyMap (see the stereo_calib.cpp sample in OpenCV samples directory). When (0,0) |
|
is passed (default), it is set to the original imageSize . Setting it to larger value can help you |
|
preserve details in the original image, especially when there is a big radial distortion. |
|
@param validPixROI1 Optional output rectangles inside the rectified images where all the pixels |
|
are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller |
|
(see the picture below). |
|
@param validPixROI2 Optional output rectangles inside the rectified images where all the pixels |
|
are valid. If alpha=0 , the ROIs cover the whole images. Otherwise, they are likely to be smaller |
|
(see the picture below). |
|
|
|
The function computes the rotation matrices for each camera that (virtually) make both camera image |
|
planes the same plane. Consequently, this makes all the epipolar lines parallel and thus simplifies |
|
the dense stereo correspondence problem. The function takes the matrices computed by stereoCalibrate |
|
as input. As output, it provides two rotation matrices and also two projection matrices in the new |
|
coordinates. The function distinguishes the following two cases: |
|
|
|
- **Horizontal stereo**: the first and the second camera views are shifted relative to each other |
|
mainly along the x axis (with possible small vertical shift). In the rectified images, the |
|
corresponding epipolar lines in the left and right cameras are horizontal and have the same |
|
y-coordinate. P1 and P2 look like: |
|
|
|
\f[\texttt{P1} = \begin{bmatrix} f & 0 & cx_1 & 0 \\ 0 & f & cy & 0 \\ 0 & 0 & 1 & 0 \end{bmatrix}\f] |
|
|
|
\f[\texttt{P2} = \begin{bmatrix} f & 0 & cx_2 & T_x*f \\ 0 & f & cy & 0 \\ 0 & 0 & 1 & 0 \end{bmatrix} ,\f] |
|
|
|
where \f$T_x\f$ is a horizontal shift between the cameras and \f$cx_1=cx_2\f$ if |
|
CALIB_ZERO_DISPARITY is set. |
|
|
|
- **Vertical stereo**: the first and the second camera views are shifted relative to each other |
|
mainly in vertical direction (and probably a bit in the horizontal direction too). The epipolar |
|
lines in the rectified images are vertical and have the same x-coordinate. P1 and P2 look like: |
|
|
|
\f[\texttt{P1} = \begin{bmatrix} f & 0 & cx & 0 \\ 0 & f & cy_1 & 0 \\ 0 & 0 & 1 & 0 \end{bmatrix}\f] |
|
|
|
\f[\texttt{P2} = \begin{bmatrix} f & 0 & cx & 0 \\ 0 & f & cy_2 & T_y*f \\ 0 & 0 & 1 & 0 \end{bmatrix} ,\f] |
|
|
|
where \f$T_y\f$ is a vertical shift between the cameras and \f$cy_1=cy_2\f$ if CALIB_ZERO_DISPARITY is |
|
set. |
|
|
|
As you can see, the first three columns of P1 and P2 will effectively be the new "rectified" camera |
|
matrices. The matrices, together with R1 and R2 , can then be passed to initUndistortRectifyMap to |
|
initialize the rectification map for each camera. |
|
|
|
See below the screenshot from the stereo_calib.cpp sample. Some red horizontal lines pass through |
|
the corresponding image regions. This means that the images are well rectified, which is what most |
|
stereo correspondence algorithms rely on. The green rectangles are roi1 and roi2 . You see that |
|
their interiors are all valid pixels. |
|
|
|
![image](pics/stereo_undistort.jpg) |
|
*/ |
|
CV_EXPORTS_W void stereoRectify( InputArray cameraMatrix1, InputArray distCoeffs1, |
|
InputArray cameraMatrix2, InputArray distCoeffs2, |
|
Size imageSize, InputArray R, InputArray T, |
|
OutputArray R1, OutputArray R2, |
|
OutputArray P1, OutputArray P2, |
|
OutputArray Q, int flags = CALIB_ZERO_DISPARITY, |
|
double alpha = -1, Size newImageSize = Size(), |
|
CV_OUT Rect* validPixROI1 = 0, CV_OUT Rect* validPixROI2 = 0 ); |
|
|
|
/** @brief Computes a rectification transform for an uncalibrated stereo camera. |
|
|
|
@param points1 Array of feature points in the first image. |
|
@param points2 The corresponding points in the second image. The same formats as in |
|
findFundamentalMat are supported. |
|
@param F Input fundamental matrix. It can be computed from the same set of point pairs using |
|
findFundamentalMat . |
|
@param imgSize Size of the image. |
|
@param H1 Output rectification homography matrix for the first image. |
|
@param H2 Output rectification homography matrix for the second image. |
|
@param threshold Optional threshold used to filter out the outliers. If the parameter is greater |
|
than zero, all the point pairs that do not comply with the epipolar geometry (that is, the points |
|
for which \f$|\texttt{points2[i]}^T*\texttt{F}*\texttt{points1[i]}|>\texttt{threshold}\f$ ) are |
|
rejected prior to computing the homographies. Otherwise, all the points are considered inliers. |
|
|
|
The function computes the rectification transformations without knowing intrinsic parameters of the |
|
cameras and their relative position in the space, which explains the suffix "uncalibrated". Another |
|
related difference from stereoRectify is that the function outputs not the rectification |
|
transformations in the object (3D) space, but the planar perspective transformations encoded by the |
|
homography matrices H1 and H2 . The function implements the algorithm @cite Hartley99 . |
|
|
|
@note |
|
While the algorithm does not need to know the intrinsic parameters of the cameras, it heavily |
|
depends on the epipolar geometry. Therefore, if the camera lenses have a significant distortion, |
|
it would be better to correct it before computing the fundamental matrix and calling this |
|
function. For example, distortion coefficients can be estimated for each head of stereo camera |
|
separately by using calibrateCamera . Then, the images can be corrected using undistort , or |
|
just the point coordinates can be corrected with undistortPoints . |
|
*/ |
|
CV_EXPORTS_W bool stereoRectifyUncalibrated( InputArray points1, InputArray points2, |
|
InputArray F, Size imgSize, |
|
OutputArray H1, OutputArray H2, |
|
double threshold = 5 ); |
|
|
|
//! computes the rectification transformations for 3-head camera, where all the heads are on the same line. |
|
CV_EXPORTS_W float rectify3Collinear( InputArray cameraMatrix1, InputArray distCoeffs1, |
|
InputArray cameraMatrix2, InputArray distCoeffs2, |
|
InputArray cameraMatrix3, InputArray distCoeffs3, |
|
InputArrayOfArrays imgpt1, InputArrayOfArrays imgpt3, |
|
Size imageSize, InputArray R12, InputArray T12, |
|
InputArray R13, InputArray T13, |
|
OutputArray R1, OutputArray R2, OutputArray R3, |
|
OutputArray P1, OutputArray P2, OutputArray P3, |
|
OutputArray Q, double alpha, Size newImgSize, |
|
CV_OUT Rect* roi1, CV_OUT Rect* roi2, int flags ); |
|
|
|
/** @brief Returns the new camera matrix based on the free scaling parameter. |
|
|
|
@param cameraMatrix Input camera matrix. |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6 [, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ of |
|
4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are |
|
assumed. |
|
@param imageSize Original image size. |
|
@param alpha Free scaling parameter between 0 (when all the pixels in the undistorted image are |
|
valid) and 1 (when all the source image pixels are retained in the undistorted image). See |
|
stereoRectify for details. |
|
@param newImgSize Image size after rectification. By default, it is set to imageSize . |
|
@param validPixROI Optional output rectangle that outlines all-good-pixels region in the |
|
undistorted image. See roi1, roi2 description in stereoRectify . |
|
@param centerPrincipalPoint Optional flag that indicates whether in the new camera matrix the |
|
principal point should be at the image center or not. By default, the principal point is chosen to |
|
best fit a subset of the source image (determined by alpha) to the corrected image. |
|
@return new_camera_matrix Output new camera matrix. |
|
|
|
The function computes and returns the optimal new camera matrix based on the free scaling parameter. |
|
By varying this parameter, you may retrieve only sensible pixels alpha=0 , keep all the original |
|
image pixels if there is valuable information in the corners alpha=1 , or get something in between. |
|
When alpha\>0 , the undistorted result is likely to have some black pixels corresponding to |
|
"virtual" pixels outside of the captured distorted image. The original camera matrix, distortion |
|
coefficients, the computed new camera matrix, and newImageSize should be passed to |
|
initUndistortRectifyMap to produce the maps for remap . |
|
*/ |
|
CV_EXPORTS_W Mat getOptimalNewCameraMatrix( InputArray cameraMatrix, InputArray distCoeffs, |
|
Size imageSize, double alpha, Size newImgSize = Size(), |
|
CV_OUT Rect* validPixROI = 0, |
|
bool centerPrincipalPoint = false); |
|
|
|
/** @brief Converts points from Euclidean to homogeneous space. |
|
|
|
@param src Input vector of N-dimensional points. |
|
@param dst Output vector of N+1-dimensional points. |
|
|
|
The function converts points from Euclidean to homogeneous space by appending 1's to the tuple of |
|
point coordinates. That is, each point (x1, x2, ..., xn) is converted to (x1, x2, ..., xn, 1). |
|
*/ |
|
CV_EXPORTS_W void convertPointsToHomogeneous( InputArray src, OutputArray dst ); |
|
|
|
/** @brief Converts points from homogeneous to Euclidean space. |
|
|
|
@param src Input vector of N-dimensional points. |
|
@param dst Output vector of N-1-dimensional points. |
|
|
|
The function converts points homogeneous to Euclidean space using perspective projection. That is, |
|
each point (x1, x2, ... x(n-1), xn) is converted to (x1/xn, x2/xn, ..., x(n-1)/xn). When xn=0, the |
|
output point coordinates will be (0,0,0,...). |
|
*/ |
|
CV_EXPORTS_W void convertPointsFromHomogeneous( InputArray src, OutputArray dst ); |
|
|
|
/** @brief Converts points to/from homogeneous coordinates. |
|
|
|
@param src Input array or vector of 2D, 3D, or 4D points. |
|
@param dst Output vector of 2D, 3D, or 4D points. |
|
|
|
The function converts 2D or 3D points from/to homogeneous coordinates by calling either |
|
convertPointsToHomogeneous or convertPointsFromHomogeneous. |
|
|
|
@note The function is obsolete. Use one of the previous two functions instead. |
|
*/ |
|
CV_EXPORTS void convertPointsHomogeneous( InputArray src, OutputArray dst ); |
|
|
|
/** @brief Calculates a fundamental matrix from the corresponding points in two images. |
|
|
|
@param points1 Array of N points from the first image. The point coordinates should be |
|
floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1 . |
|
@param method Method for computing a fundamental matrix. |
|
- **CV_FM_7POINT** for a 7-point algorithm. \f$N = 7\f$ |
|
- **CV_FM_8POINT** for an 8-point algorithm. \f$N \ge 8\f$ |
|
- **CV_FM_RANSAC** for the RANSAC algorithm. \f$N \ge 8\f$ |
|
- **CV_FM_LMEDS** for the LMedS algorithm. \f$N \ge 8\f$ |
|
@param ransacReprojThreshold Parameter used only for RANSAC. It is the maximum distance from a point to an epipolar |
|
line in pixels, beyond which the point is considered an outlier and is not used for computing the |
|
final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the |
|
point localization, image resolution, and the image noise. |
|
@param confidence Parameter used for the RANSAC and LMedS methods only. It specifies a desirable level |
|
of confidence (probability) that the estimated matrix is correct. |
|
@param mask |
|
|
|
The epipolar geometry is described by the following equation: |
|
|
|
\f[[p_2; 1]^T F [p_1; 1] = 0\f] |
|
|
|
where \f$F\f$ is a fundamental matrix, \f$p_1\f$ and \f$p_2\f$ are corresponding points in the first and the |
|
second images, respectively. |
|
|
|
The function calculates the fundamental matrix using one of four methods listed above and returns |
|
the found fundamental matrix. Normally just one matrix is found. But in case of the 7-point |
|
algorithm, the function may return up to 3 solutions ( \f$9 \times 3\f$ matrix that stores all 3 |
|
matrices sequentially). |
|
|
|
The calculated fundamental matrix may be passed further to computeCorrespondEpilines that finds the |
|
epipolar lines corresponding to the specified points. It can also be passed to |
|
stereoRectifyUncalibrated to compute the rectification transformation. : |
|
@code |
|
// Example. Estimation of fundamental matrix using the RANSAC algorithm |
|
int point_count = 100; |
|
vector<Point2f> points1(point_count); |
|
vector<Point2f> points2(point_count); |
|
|
|
// initialize the points here ... |
|
for( int i = 0; i < point_count; i++ ) |
|
{ |
|
points1[i] = ...; |
|
points2[i] = ...; |
|
} |
|
|
|
Mat fundamental_matrix = |
|
findFundamentalMat(points1, points2, FM_RANSAC, 3, 0.99); |
|
@endcode |
|
*/ |
|
CV_EXPORTS_W Mat findFundamentalMat( InputArray points1, InputArray points2, |
|
int method = FM_RANSAC, |
|
double ransacReprojThreshold = 3., double confidence = 0.99, |
|
OutputArray mask = noArray() ); |
|
|
|
/** @overload */ |
|
CV_EXPORTS Mat findFundamentalMat( InputArray points1, InputArray points2, |
|
OutputArray mask, int method = FM_RANSAC, |
|
double ransacReprojThreshold = 3., double confidence = 0.99 ); |
|
|
|
/** @brief Calculates an essential matrix from the corresponding points in two images. |
|
|
|
@param points1 Array of N (N \>= 5) 2D points from the first image. The point coordinates should |
|
be floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1 . |
|
@param cameraMatrix Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
Note that this function assumes that points1 and points2 are feature points from cameras with the |
|
same camera matrix. |
|
@param method Method for computing an essential matrix. |
|
- **RANSAC** for the RANSAC algorithm. |
|
- **LMEDS** for the LMedS algorithm. |
|
@param prob Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of |
|
confidence (probability) that the estimated matrix is correct. |
|
@param threshold Parameter used for RANSAC. It is the maximum distance from a point to an epipolar |
|
line in pixels, beyond which the point is considered an outlier and is not used for computing the |
|
final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the |
|
point localization, image resolution, and the image noise. |
|
@param mask Output array of N elements, every element of which is set to 0 for outliers and to 1 |
|
for the other points. The array is computed only in the RANSAC and LMedS methods. |
|
|
|
This function estimates essential matrix based on the five-point algorithm solver in @cite Nister03 . |
|
@cite SteweniusCFS is also a related. The epipolar geometry is described by the following equation: |
|
|
|
\f[[p_2; 1]^T K^{-T} E K^{-1} [p_1; 1] = 0\f] |
|
|
|
where \f$E\f$ is an essential matrix, \f$p_1\f$ and \f$p_2\f$ are corresponding points in the first and the |
|
second images, respectively. The result of this function may be passed further to |
|
decomposeEssentialMat or recoverPose to recover the relative pose between cameras. |
|
*/ |
|
CV_EXPORTS_W Mat findEssentialMat( InputArray points1, InputArray points2, |
|
InputArray cameraMatrix, int method = RANSAC, |
|
double prob = 0.999, double threshold = 1.0, |
|
OutputArray mask = noArray() ); |
|
|
|
/** @overload |
|
@param points1 Array of N (N \>= 5) 2D points from the first image. The point coordinates should |
|
be floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1 . |
|
@param focal focal length of the camera. Note that this function assumes that points1 and points2 |
|
are feature points from cameras with same focal length and principal point. |
|
@param pp principal point of the camera. |
|
@param method Method for computing a fundamental matrix. |
|
- **RANSAC** for the RANSAC algorithm. |
|
- **LMEDS** for the LMedS algorithm. |
|
@param threshold Parameter used for RANSAC. It is the maximum distance from a point to an epipolar |
|
line in pixels, beyond which the point is considered an outlier and is not used for computing the |
|
final fundamental matrix. It can be set to something like 1-3, depending on the accuracy of the |
|
point localization, image resolution, and the image noise. |
|
@param prob Parameter used for the RANSAC or LMedS methods only. It specifies a desirable level of |
|
confidence (probability) that the estimated matrix is correct. |
|
@param mask Output array of N elements, every element of which is set to 0 for outliers and to 1 |
|
for the other points. The array is computed only in the RANSAC and LMedS methods. |
|
|
|
This function differs from the one above that it computes camera matrix from focal length and |
|
principal point: |
|
|
|
\f[K = |
|
\begin{bmatrix} |
|
f & 0 & x_{pp} \\ |
|
0 & f & y_{pp} \\ |
|
0 & 0 & 1 |
|
\end{bmatrix}\f] |
|
*/ |
|
CV_EXPORTS_W Mat findEssentialMat( InputArray points1, InputArray points2, |
|
double focal = 1.0, Point2d pp = Point2d(0, 0), |
|
int method = RANSAC, double prob = 0.999, |
|
double threshold = 1.0, OutputArray mask = noArray() ); |
|
|
|
/** @brief Decompose an essential matrix to possible rotations and translation. |
|
|
|
@param E The input essential matrix. |
|
@param R1 One possible rotation matrix. |
|
@param R2 Another possible rotation matrix. |
|
@param t One possible translation. |
|
|
|
This function decompose an essential matrix E using svd decomposition @cite HartleyZ00 . Generally 4 |
|
possible poses exists for a given E. They are \f$[R_1, t]\f$, \f$[R_1, -t]\f$, \f$[R_2, t]\f$, \f$[R_2, -t]\f$. By |
|
decomposing E, you can only get the direction of the translation, so the function returns unit t. |
|
*/ |
|
CV_EXPORTS_W void decomposeEssentialMat( InputArray E, OutputArray R1, OutputArray R2, OutputArray t ); |
|
|
|
/** @brief Recover relative camera rotation and translation from an estimated essential matrix and the |
|
corresponding points in two images, using cheirality check. Returns the number of inliers which pass |
|
the check. |
|
|
|
@param E The input essential matrix. |
|
@param points1 Array of N 2D points from the first image. The point coordinates should be |
|
floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1 . |
|
@param cameraMatrix Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
Note that this function assumes that points1 and points2 are feature points from cameras with the |
|
same camera matrix. |
|
@param R Recovered relative rotation. |
|
@param t Recovered relative translation. |
|
@param mask Input/output mask for inliers in points1 and points2. |
|
: If it is not empty, then it marks inliers in points1 and points2 for then given essential |
|
matrix E. Only these inliers will be used to recover pose. In the output mask only inliers |
|
which pass the cheirality check. |
|
This function decomposes an essential matrix using decomposeEssentialMat and then verifies possible |
|
pose hypotheses by doing cheirality check. The cheirality check basically means that the |
|
triangulated 3D points should have positive depth. Some details can be found in @cite Nister03 . |
|
|
|
This function can be used to process output E and mask from findEssentialMat. In this scenario, |
|
points1 and points2 are the same input for findEssentialMat. : |
|
@code |
|
// Example. Estimation of fundamental matrix using the RANSAC algorithm |
|
int point_count = 100; |
|
vector<Point2f> points1(point_count); |
|
vector<Point2f> points2(point_count); |
|
|
|
// initialize the points here ... |
|
for( int i = 0; i < point_count; i++ ) |
|
{ |
|
points1[i] = ...; |
|
points2[i] = ...; |
|
} |
|
|
|
// cametra matrix with both focal lengths = 1, and principal point = (0, 0) |
|
Mat cameraMatrix = Mat::eye(3, 3, CV_64F); |
|
|
|
Mat E, R, t, mask; |
|
|
|
E = findEssentialMat(points1, points2, cameraMatrix, RANSAC, 0.999, 1.0, mask); |
|
recoverPose(E, points1, points2, cameraMatrix, R, t, mask); |
|
@endcode |
|
*/ |
|
CV_EXPORTS_W int recoverPose( InputArray E, InputArray points1, InputArray points2, |
|
InputArray cameraMatrix, OutputArray R, OutputArray t, |
|
InputOutputArray mask = noArray() ); |
|
|
|
/** @overload |
|
@param E The input essential matrix. |
|
@param points1 Array of N 2D points from the first image. The point coordinates should be |
|
floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1 . |
|
@param R Recovered relative rotation. |
|
@param t Recovered relative translation. |
|
@param focal Focal length of the camera. Note that this function assumes that points1 and points2 |
|
are feature points from cameras with same focal length and principal point. |
|
@param pp principal point of the camera. |
|
@param mask Input/output mask for inliers in points1 and points2. |
|
: If it is not empty, then it marks inliers in points1 and points2 for then given essential |
|
matrix E. Only these inliers will be used to recover pose. In the output mask only inliers |
|
which pass the cheirality check. |
|
|
|
This function differs from the one above that it computes camera matrix from focal length and |
|
principal point: |
|
|
|
\f[K = |
|
\begin{bmatrix} |
|
f & 0 & x_{pp} \\ |
|
0 & f & y_{pp} \\ |
|
0 & 0 & 1 |
|
\end{bmatrix}\f] |
|
*/ |
|
CV_EXPORTS_W int recoverPose( InputArray E, InputArray points1, InputArray points2, |
|
OutputArray R, OutputArray t, |
|
double focal = 1.0, Point2d pp = Point2d(0, 0), |
|
InputOutputArray mask = noArray() ); |
|
|
|
/** @overload |
|
@param E The input essential matrix. |
|
@param points1 Array of N 2D points from the first image. The point coordinates should be |
|
floating-point (single or double precision). |
|
@param points2 Array of the second image points of the same size and format as points1. |
|
@param cameraMatrix Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
Note that this function assumes that points1 and points2 are feature points from cameras with the |
|
same camera matrix. |
|
@param R Recovered relative rotation. |
|
@param t Recovered relative translation. |
|
@param distanceThresh threshold distance which is used to filter out far away points (i.e. infinite points). |
|
@param mask Input/output mask for inliers in points1 and points2. |
|
: If it is not empty, then it marks inliers in points1 and points2 for then given essential |
|
matrix E. Only these inliers will be used to recover pose. In the output mask only inliers |
|
which pass the cheirality check. |
|
@param triangulatedPoints 3d points which were reconstructed by triangulation. |
|
*/ |
|
|
|
CV_EXPORTS_W int recoverPose( InputArray E, InputArray points1, InputArray points2, |
|
InputArray cameraMatrix, OutputArray R, OutputArray t, double distanceThresh, InputOutputArray mask = noArray(), |
|
OutputArray triangulatedPoints = noArray()); |
|
|
|
/** @brief For points in an image of a stereo pair, computes the corresponding epilines in the other image. |
|
|
|
@param points Input points. \f$N \times 1\f$ or \f$1 \times N\f$ matrix of type CV_32FC2 or |
|
vector\<Point2f\> . |
|
@param whichImage Index of the image (1 or 2) that contains the points . |
|
@param F Fundamental matrix that can be estimated using findFundamentalMat or stereoRectify . |
|
@param lines Output vector of the epipolar lines corresponding to the points in the other image. |
|
Each line \f$ax + by + c=0\f$ is encoded by 3 numbers \f$(a, b, c)\f$ . |
|
|
|
For every point in one of the two images of a stereo pair, the function finds the equation of the |
|
corresponding epipolar line in the other image. |
|
|
|
From the fundamental matrix definition (see findFundamentalMat ), line \f$l^{(2)}_i\f$ in the second |
|
image for the point \f$p^{(1)}_i\f$ in the first image (when whichImage=1 ) is computed as: |
|
|
|
\f[l^{(2)}_i = F p^{(1)}_i\f] |
|
|
|
And vice versa, when whichImage=2, \f$l^{(1)}_i\f$ is computed from \f$p^{(2)}_i\f$ as: |
|
|
|
\f[l^{(1)}_i = F^T p^{(2)}_i\f] |
|
|
|
Line coefficients are defined up to a scale. They are normalized so that \f$a_i^2+b_i^2=1\f$ . |
|
*/ |
|
CV_EXPORTS_W void computeCorrespondEpilines( InputArray points, int whichImage, |
|
InputArray F, OutputArray lines ); |
|
|
|
/** @brief Reconstructs points by triangulation. |
|
|
|
@param projMatr1 3x4 projection matrix of the first camera. |
|
@param projMatr2 3x4 projection matrix of the second camera. |
|
@param projPoints1 2xN array of feature points in the first image. In case of c++ version it can |
|
be also a vector of feature points or two-channel matrix of size 1xN or Nx1. |
|
@param projPoints2 2xN array of corresponding points in the second image. In case of c++ version |
|
it can be also a vector of feature points or two-channel matrix of size 1xN or Nx1. |
|
@param points4D 4xN array of reconstructed points in homogeneous coordinates. |
|
|
|
The function reconstructs 3-dimensional points (in homogeneous coordinates) by using their |
|
observations with a stereo camera. Projections matrices can be obtained from stereoRectify. |
|
|
|
@note |
|
Keep in mind that all input data should be of float type in order for this function to work. |
|
|
|
@sa |
|
reprojectImageTo3D |
|
*/ |
|
CV_EXPORTS_W void triangulatePoints( InputArray projMatr1, InputArray projMatr2, |
|
InputArray projPoints1, InputArray projPoints2, |
|
OutputArray points4D ); |
|
|
|
/** @brief Refines coordinates of corresponding points. |
|
|
|
@param F 3x3 fundamental matrix. |
|
@param points1 1xN array containing the first set of points. |
|
@param points2 1xN array containing the second set of points. |
|
@param newPoints1 The optimized points1. |
|
@param newPoints2 The optimized points2. |
|
|
|
The function implements the Optimal Triangulation Method (see Multiple View Geometry for details). |
|
For each given point correspondence points1[i] \<-\> points2[i], and a fundamental matrix F, it |
|
computes the corrected correspondences newPoints1[i] \<-\> newPoints2[i] that minimize the geometric |
|
error \f$d(points1[i], newPoints1[i])^2 + d(points2[i],newPoints2[i])^2\f$ (where \f$d(a,b)\f$ is the |
|
geometric distance between points \f$a\f$ and \f$b\f$ ) subject to the epipolar constraint |
|
\f$newPoints2^T * F * newPoints1 = 0\f$ . |
|
*/ |
|
CV_EXPORTS_W void correctMatches( InputArray F, InputArray points1, InputArray points2, |
|
OutputArray newPoints1, OutputArray newPoints2 ); |
|
|
|
/** @brief Filters off small noise blobs (speckles) in the disparity map |
|
|
|
@param img The input 16-bit signed disparity image |
|
@param newVal The disparity value used to paint-off the speckles |
|
@param maxSpeckleSize The maximum speckle size to consider it a speckle. Larger blobs are not |
|
affected by the algorithm |
|
@param maxDiff Maximum difference between neighbor disparity pixels to put them into the same |
|
blob. Note that since StereoBM, StereoSGBM and may be other algorithms return a fixed-point |
|
disparity map, where disparity values are multiplied by 16, this scale factor should be taken into |
|
account when specifying this parameter value. |
|
@param buf The optional temporary buffer to avoid memory allocation within the function. |
|
*/ |
|
CV_EXPORTS_W void filterSpeckles( InputOutputArray img, double newVal, |
|
int maxSpeckleSize, double maxDiff, |
|
InputOutputArray buf = noArray() ); |
|
|
|
//! computes valid disparity ROI from the valid ROIs of the rectified images (that are returned by cv::stereoRectify()) |
|
CV_EXPORTS_W Rect getValidDisparityROI( Rect roi1, Rect roi2, |
|
int minDisparity, int numberOfDisparities, |
|
int SADWindowSize ); |
|
|
|
//! validates disparity using the left-right check. The matrix "cost" should be computed by the stereo correspondence algorithm |
|
CV_EXPORTS_W void validateDisparity( InputOutputArray disparity, InputArray cost, |
|
int minDisparity, int numberOfDisparities, |
|
int disp12MaxDisp = 1 ); |
|
|
|
/** @brief Reprojects a disparity image to 3D space. |
|
|
|
@param disparity Input single-channel 8-bit unsigned, 16-bit signed, 32-bit signed or 32-bit |
|
floating-point disparity image. If 16-bit signed format is used, the values are assumed to have no |
|
fractional bits. |
|
@param _3dImage Output 3-channel floating-point image of the same size as disparity . Each |
|
element of _3dImage(x,y) contains 3D coordinates of the point (x,y) computed from the disparity |
|
map. |
|
@param Q \f$4 \times 4\f$ perspective transformation matrix that can be obtained with stereoRectify. |
|
@param handleMissingValues Indicates, whether the function should handle missing values (i.e. |
|
points where the disparity was not computed). If handleMissingValues=true, then pixels with the |
|
minimal disparity that corresponds to the outliers (see StereoMatcher::compute ) are transformed |
|
to 3D points with a very large Z value (currently set to 10000). |
|
@param ddepth The optional output array depth. If it is -1, the output image will have CV_32F |
|
depth. ddepth can also be set to CV_16S, CV_32S or CV_32F. |
|
|
|
The function transforms a single-channel disparity map to a 3-channel image representing a 3D |
|
surface. That is, for each pixel (x,y) and the corresponding disparity d=disparity(x,y) , it |
|
computes: |
|
|
|
\f[\begin{array}{l} [X \; Y \; Z \; W]^T = \texttt{Q} *[x \; y \; \texttt{disparity} (x,y) \; 1]^T \\ \texttt{\_3dImage} (x,y) = (X/W, \; Y/W, \; Z/W) \end{array}\f] |
|
|
|
The matrix Q can be an arbitrary \f$4 \times 4\f$ matrix (for example, the one computed by |
|
stereoRectify). To reproject a sparse set of points {(x,y,d),...} to 3D space, use |
|
perspectiveTransform . |
|
*/ |
|
CV_EXPORTS_W void reprojectImageTo3D( InputArray disparity, |
|
OutputArray _3dImage, InputArray Q, |
|
bool handleMissingValues = false, |
|
int ddepth = -1 ); |
|
|
|
/** @brief Calculates the Sampson Distance between two points. |
|
|
|
The function cv::sampsonDistance calculates and returns the first order approximation of the geometric error as: |
|
\f[ |
|
sd( \texttt{pt1} , \texttt{pt2} )= |
|
\frac{(\texttt{pt2}^t \cdot \texttt{F} \cdot \texttt{pt1})^2} |
|
{((\texttt{F} \cdot \texttt{pt1})(0))^2 + |
|
((\texttt{F} \cdot \texttt{pt1})(1))^2 + |
|
((\texttt{F}^t \cdot \texttt{pt2})(0))^2 + |
|
((\texttt{F}^t \cdot \texttt{pt2})(1))^2} |
|
\f] |
|
The fundamental matrix may be calculated using the cv::findFundamentalMat function. See @cite HartleyZ00 11.4.3 for details. |
|
@param pt1 first homogeneous 2d point |
|
@param pt2 second homogeneous 2d point |
|
@param F fundamental matrix |
|
@return The computed Sampson distance. |
|
*/ |
|
CV_EXPORTS_W double sampsonDistance(InputArray pt1, InputArray pt2, InputArray F); |
|
|
|
/** @brief Computes an optimal affine transformation between two 3D point sets. |
|
|
|
It computes |
|
\f[ |
|
\begin{bmatrix} |
|
x\\ |
|
y\\ |
|
z\\ |
|
\end{bmatrix} |
|
= |
|
\begin{bmatrix} |
|
a_{11} & a_{12} & a_{13}\\ |
|
a_{21} & a_{22} & a_{23}\\ |
|
a_{31} & a_{32} & a_{33}\\ |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
X\\ |
|
Y\\ |
|
Z\\ |
|
\end{bmatrix} |
|
+ |
|
\begin{bmatrix} |
|
b_1\\ |
|
b_2\\ |
|
b_3\\ |
|
\end{bmatrix} |
|
\f] |
|
|
|
@param src First input 3D point set containing \f$(X,Y,Z)\f$. |
|
@param dst Second input 3D point set containing \f$(x,y,z)\f$. |
|
@param out Output 3D affine transformation matrix \f$3 \times 4\f$ of the form |
|
\f[ |
|
\begin{bmatrix} |
|
a_{11} & a_{12} & a_{13} & b_1\\ |
|
a_{21} & a_{22} & a_{23} & b_2\\ |
|
a_{31} & a_{32} & a_{33} & b_3\\ |
|
\end{bmatrix} |
|
\f] |
|
@param inliers Output vector indicating which points are inliers (1-inlier, 0-outlier). |
|
@param ransacThreshold Maximum reprojection error in the RANSAC algorithm to consider a point as |
|
an inlier. |
|
@param confidence Confidence level, between 0 and 1, for the estimated transformation. Anything |
|
between 0.95 and 0.99 is usually good enough. Values too close to 1 can slow down the estimation |
|
significantly. Values lower than 0.8-0.9 can result in an incorrectly estimated transformation. |
|
|
|
The function estimates an optimal 3D affine transformation between two 3D point sets using the |
|
RANSAC algorithm. |
|
*/ |
|
CV_EXPORTS_W int estimateAffine3D(InputArray src, InputArray dst, |
|
OutputArray out, OutputArray inliers, |
|
double ransacThreshold = 3, double confidence = 0.99); |
|
|
|
/** @brief Computes an optimal affine transformation between two 2D point sets. |
|
|
|
It computes |
|
\f[ |
|
\begin{bmatrix} |
|
x\\ |
|
y\\ |
|
\end{bmatrix} |
|
= |
|
\begin{bmatrix} |
|
a_{11} & a_{12}\\ |
|
a_{21} & a_{22}\\ |
|
\end{bmatrix} |
|
\begin{bmatrix} |
|
X\\ |
|
Y\\ |
|
\end{bmatrix} |
|
+ |
|
\begin{bmatrix} |
|
b_1\\ |
|
b_2\\ |
|
\end{bmatrix} |
|
\f] |
|
|
|
@param from First input 2D point set containing \f$(X,Y)\f$. |
|
@param to Second input 2D point set containing \f$(x,y)\f$. |
|
@param inliers Output vector indicating which points are inliers (1-inlier, 0-outlier). |
|
@param method Robust method used to compute transformation. The following methods are possible: |
|
- cv::RANSAC - RANSAC-based robust method |
|
- cv::LMEDS - Least-Median robust method |
|
RANSAC is the default method. |
|
@param ransacReprojThreshold Maximum reprojection error in the RANSAC algorithm to consider |
|
a point as an inlier. Applies only to RANSAC. |
|
@param maxIters The maximum number of robust method iterations. |
|
@param confidence Confidence level, between 0 and 1, for the estimated transformation. Anything |
|
between 0.95 and 0.99 is usually good enough. Values too close to 1 can slow down the estimation |
|
significantly. Values lower than 0.8-0.9 can result in an incorrectly estimated transformation. |
|
@param refineIters Maximum number of iterations of refining algorithm (Levenberg-Marquardt). |
|
Passing 0 will disable refining, so the output matrix will be output of robust method. |
|
|
|
@return Output 2D affine transformation matrix \f$2 \times 3\f$ or empty matrix if transformation |
|
could not be estimated. The returned matrix has the following form: |
|
\f[ |
|
\begin{bmatrix} |
|
a_{11} & a_{12} & b_1\\ |
|
a_{21} & a_{22} & b_2\\ |
|
\end{bmatrix} |
|
\f] |
|
|
|
The function estimates an optimal 2D affine transformation between two 2D point sets using the |
|
selected robust algorithm. |
|
|
|
The computed transformation is then refined further (using only inliers) with the |
|
Levenberg-Marquardt method to reduce the re-projection error even more. |
|
|
|
@note |
|
The RANSAC method can handle practically any ratio of outliers but needs a threshold to |
|
distinguish inliers from outliers. The method LMeDS does not need any threshold but it works |
|
correctly only when there are more than 50% of inliers. |
|
|
|
@sa estimateAffinePartial2D, getAffineTransform |
|
*/ |
|
CV_EXPORTS_W cv::Mat estimateAffine2D(InputArray from, InputArray to, OutputArray inliers = noArray(), |
|
int method = RANSAC, double ransacReprojThreshold = 3, |
|
size_t maxIters = 2000, double confidence = 0.99, |
|
size_t refineIters = 10); |
|
|
|
/** @brief Computes an optimal limited affine transformation with 4 degrees of freedom between |
|
two 2D point sets. |
|
|
|
@param from First input 2D point set. |
|
@param to Second input 2D point set. |
|
@param inliers Output vector indicating which points are inliers. |
|
@param method Robust method used to compute transformation. The following methods are possible: |
|
- cv::RANSAC - RANSAC-based robust method |
|
- cv::LMEDS - Least-Median robust method |
|
RANSAC is the default method. |
|
@param ransacReprojThreshold Maximum reprojection error in the RANSAC algorithm to consider |
|
a point as an inlier. Applies only to RANSAC. |
|
@param maxIters The maximum number of robust method iterations. |
|
@param confidence Confidence level, between 0 and 1, for the estimated transformation. Anything |
|
between 0.95 and 0.99 is usually good enough. Values too close to 1 can slow down the estimation |
|
significantly. Values lower than 0.8-0.9 can result in an incorrectly estimated transformation. |
|
@param refineIters Maximum number of iterations of refining algorithm (Levenberg-Marquardt). |
|
Passing 0 will disable refining, so the output matrix will be output of robust method. |
|
|
|
@return Output 2D affine transformation (4 degrees of freedom) matrix \f$2 \times 3\f$ or |
|
empty matrix if transformation could not be estimated. |
|
|
|
The function estimates an optimal 2D affine transformation with 4 degrees of freedom limited to |
|
combinations of translation, rotation, and uniform scaling. Uses the selected algorithm for robust |
|
estimation. |
|
|
|
The computed transformation is then refined further (using only inliers) with the |
|
Levenberg-Marquardt method to reduce the re-projection error even more. |
|
|
|
Estimated transformation matrix is: |
|
\f[ \begin{bmatrix} \cos(\theta) \cdot s & -\sin(\theta) \cdot s & t_x \\ |
|
\sin(\theta) \cdot s & \cos(\theta) \cdot s & t_y |
|
\end{bmatrix} \f] |
|
Where \f$ \theta \f$ is the rotation angle, \f$ s \f$ the scaling factor and \f$ t_x, t_y \f$ are |
|
translations in \f$ x, y \f$ axes respectively. |
|
|
|
@note |
|
The RANSAC method can handle practically any ratio of outliers but need a threshold to |
|
distinguish inliers from outliers. The method LMeDS does not need any threshold but it works |
|
correctly only when there are more than 50% of inliers. |
|
|
|
@sa estimateAffine2D, getAffineTransform |
|
*/ |
|
CV_EXPORTS_W cv::Mat estimateAffinePartial2D(InputArray from, InputArray to, OutputArray inliers = noArray(), |
|
int method = RANSAC, double ransacReprojThreshold = 3, |
|
size_t maxIters = 2000, double confidence = 0.99, |
|
size_t refineIters = 10); |
|
|
|
/** @example samples/cpp/tutorial_code/features2D/Homography/decompose_homography.cpp |
|
An example program with homography decomposition. |
|
|
|
Check @ref tutorial_homography "the corresponding tutorial" for more details. |
|
*/ |
|
|
|
/** @brief Decompose a homography matrix to rotation(s), translation(s) and plane normal(s). |
|
|
|
@param H The input homography matrix between two images. |
|
@param K The input intrinsic camera calibration matrix. |
|
@param rotations Array of rotation matrices. |
|
@param translations Array of translation matrices. |
|
@param normals Array of plane normal matrices. |
|
|
|
This function extracts relative camera motion between two views observing a planar object from the |
|
homography H induced by the plane. The intrinsic camera matrix K must also be provided. The function |
|
may return up to four mathematical solution sets. At least two of the solutions may further be |
|
invalidated if point correspondences are available by applying positive depth constraint (all points |
|
must be in front of the camera). The decomposition method is described in detail in @cite Malis . |
|
*/ |
|
CV_EXPORTS_W int decomposeHomographyMat(InputArray H, |
|
InputArray K, |
|
OutputArrayOfArrays rotations, |
|
OutputArrayOfArrays translations, |
|
OutputArrayOfArrays normals); |
|
|
|
/** @brief Filters homography decompositions based on additional information. |
|
|
|
@param rotations Vector of rotation matrices. |
|
@param normals Vector of plane normal matrices. |
|
@param beforePoints Vector of (rectified) visible reference points before the homography is applied |
|
@param afterPoints Vector of (rectified) visible reference points after the homography is applied |
|
@param possibleSolutions Vector of int indices representing the viable solution set after filtering |
|
@param pointsMask optional Mat/Vector of 8u type representing the mask for the inliers as given by the findHomography function |
|
|
|
This function is intended to filter the output of the decomposeHomographyMat based on additional |
|
information as described in @cite Malis . The summary of the method: the decomposeHomographyMat function |
|
returns 2 unique solutions and their "opposites" for a total of 4 solutions. If we have access to the |
|
sets of points visible in the camera frame before and after the homography transformation is applied, |
|
we can determine which are the true potential solutions and which are the opposites by verifying which |
|
homographies are consistent with all visible reference points being in front of the camera. The inputs |
|
are left unchanged; the filtered solution set is returned as indices into the existing one. |
|
|
|
*/ |
|
CV_EXPORTS_W void filterHomographyDecompByVisibleRefpoints(InputArrayOfArrays rotations, |
|
InputArrayOfArrays normals, |
|
InputArray beforePoints, |
|
InputArray afterPoints, |
|
OutputArray possibleSolutions, |
|
InputArray pointsMask = noArray()); |
|
|
|
/** @brief The base class for stereo correspondence algorithms. |
|
*/ |
|
class CV_EXPORTS_W StereoMatcher : public Algorithm |
|
{ |
|
public: |
|
enum { DISP_SHIFT = 4, |
|
DISP_SCALE = (1 << DISP_SHIFT) |
|
}; |
|
|
|
/** @brief Computes disparity map for the specified stereo pair |
|
|
|
@param left Left 8-bit single-channel image. |
|
@param right Right image of the same size and the same type as the left one. |
|
@param disparity Output disparity map. It has the same size as the input images. Some algorithms, |
|
like StereoBM or StereoSGBM compute 16-bit fixed-point disparity map (where each disparity value |
|
has 4 fractional bits), whereas other algorithms output 32-bit floating-point disparity map. |
|
*/ |
|
CV_WRAP virtual void compute( InputArray left, InputArray right, |
|
OutputArray disparity ) = 0; |
|
|
|
CV_WRAP virtual int getMinDisparity() const = 0; |
|
CV_WRAP virtual void setMinDisparity(int minDisparity) = 0; |
|
|
|
CV_WRAP virtual int getNumDisparities() const = 0; |
|
CV_WRAP virtual void setNumDisparities(int numDisparities) = 0; |
|
|
|
CV_WRAP virtual int getBlockSize() const = 0; |
|
CV_WRAP virtual void setBlockSize(int blockSize) = 0; |
|
|
|
CV_WRAP virtual int getSpeckleWindowSize() const = 0; |
|
CV_WRAP virtual void setSpeckleWindowSize(int speckleWindowSize) = 0; |
|
|
|
CV_WRAP virtual int getSpeckleRange() const = 0; |
|
CV_WRAP virtual void setSpeckleRange(int speckleRange) = 0; |
|
|
|
CV_WRAP virtual int getDisp12MaxDiff() const = 0; |
|
CV_WRAP virtual void setDisp12MaxDiff(int disp12MaxDiff) = 0; |
|
}; |
|
|
|
|
|
/** @brief Class for computing stereo correspondence using the block matching algorithm, introduced and |
|
contributed to OpenCV by K. Konolige. |
|
*/ |
|
class CV_EXPORTS_W StereoBM : public StereoMatcher |
|
{ |
|
public: |
|
enum { PREFILTER_NORMALIZED_RESPONSE = 0, |
|
PREFILTER_XSOBEL = 1 |
|
}; |
|
|
|
CV_WRAP virtual int getPreFilterType() const = 0; |
|
CV_WRAP virtual void setPreFilterType(int preFilterType) = 0; |
|
|
|
CV_WRAP virtual int getPreFilterSize() const = 0; |
|
CV_WRAP virtual void setPreFilterSize(int preFilterSize) = 0; |
|
|
|
CV_WRAP virtual int getPreFilterCap() const = 0; |
|
CV_WRAP virtual void setPreFilterCap(int preFilterCap) = 0; |
|
|
|
CV_WRAP virtual int getTextureThreshold() const = 0; |
|
CV_WRAP virtual void setTextureThreshold(int textureThreshold) = 0; |
|
|
|
CV_WRAP virtual int getUniquenessRatio() const = 0; |
|
CV_WRAP virtual void setUniquenessRatio(int uniquenessRatio) = 0; |
|
|
|
CV_WRAP virtual int getSmallerBlockSize() const = 0; |
|
CV_WRAP virtual void setSmallerBlockSize(int blockSize) = 0; |
|
|
|
CV_WRAP virtual Rect getROI1() const = 0; |
|
CV_WRAP virtual void setROI1(Rect roi1) = 0; |
|
|
|
CV_WRAP virtual Rect getROI2() const = 0; |
|
CV_WRAP virtual void setROI2(Rect roi2) = 0; |
|
|
|
/** @brief Creates StereoBM object |
|
|
|
@param numDisparities the disparity search range. For each pixel algorithm will find the best |
|
disparity from 0 (default minimum disparity) to numDisparities. The search range can then be |
|
shifted by changing the minimum disparity. |
|
@param blockSize the linear size of the blocks compared by the algorithm. The size should be odd |
|
(as the block is centered at the current pixel). Larger block size implies smoother, though less |
|
accurate disparity map. Smaller block size gives more detailed disparity map, but there is higher |
|
chance for algorithm to find a wrong correspondence. |
|
|
|
The function create StereoBM object. You can then call StereoBM::compute() to compute disparity for |
|
a specific stereo pair. |
|
*/ |
|
CV_WRAP static Ptr<StereoBM> create(int numDisparities = 0, int blockSize = 21); |
|
}; |
|
|
|
/** @brief The class implements the modified H. Hirschmuller algorithm @cite HH08 that differs from the original |
|
one as follows: |
|
|
|
- By default, the algorithm is single-pass, which means that you consider only 5 directions |
|
instead of 8. Set mode=StereoSGBM::MODE_HH in createStereoSGBM to run the full variant of the |
|
algorithm but beware that it may consume a lot of memory. |
|
- The algorithm matches blocks, not individual pixels. Though, setting blockSize=1 reduces the |
|
blocks to single pixels. |
|
- Mutual information cost function is not implemented. Instead, a simpler Birchfield-Tomasi |
|
sub-pixel metric from @cite BT98 is used. Though, the color images are supported as well. |
|
- Some pre- and post- processing steps from K. Konolige algorithm StereoBM are included, for |
|
example: pre-filtering (StereoBM::PREFILTER_XSOBEL type) and post-filtering (uniqueness |
|
check, quadratic interpolation and speckle filtering). |
|
|
|
@note |
|
- (Python) An example illustrating the use of the StereoSGBM matching algorithm can be found |
|
at opencv_source_code/samples/python/stereo_match.py |
|
*/ |
|
class CV_EXPORTS_W StereoSGBM : public StereoMatcher |
|
{ |
|
public: |
|
enum |
|
{ |
|
MODE_SGBM = 0, |
|
MODE_HH = 1, |
|
MODE_SGBM_3WAY = 2, |
|
MODE_HH4 = 3 |
|
}; |
|
|
|
CV_WRAP virtual int getPreFilterCap() const = 0; |
|
CV_WRAP virtual void setPreFilterCap(int preFilterCap) = 0; |
|
|
|
CV_WRAP virtual int getUniquenessRatio() const = 0; |
|
CV_WRAP virtual void setUniquenessRatio(int uniquenessRatio) = 0; |
|
|
|
CV_WRAP virtual int getP1() const = 0; |
|
CV_WRAP virtual void setP1(int P1) = 0; |
|
|
|
CV_WRAP virtual int getP2() const = 0; |
|
CV_WRAP virtual void setP2(int P2) = 0; |
|
|
|
CV_WRAP virtual int getMode() const = 0; |
|
CV_WRAP virtual void setMode(int mode) = 0; |
|
|
|
/** @brief Creates StereoSGBM object |
|
|
|
@param minDisparity Minimum possible disparity value. Normally, it is zero but sometimes |
|
rectification algorithms can shift images, so this parameter needs to be adjusted accordingly. |
|
@param numDisparities Maximum disparity minus minimum disparity. The value is always greater than |
|
zero. In the current implementation, this parameter must be divisible by 16. |
|
@param blockSize Matched block size. It must be an odd number \>=1 . Normally, it should be |
|
somewhere in the 3..11 range. |
|
@param P1 The first parameter controlling the disparity smoothness. See below. |
|
@param P2 The second parameter controlling the disparity smoothness. The larger the values are, |
|
the smoother the disparity is. P1 is the penalty on the disparity change by plus or minus 1 |
|
between neighbor pixels. P2 is the penalty on the disparity change by more than 1 between neighbor |
|
pixels. The algorithm requires P2 \> P1 . See stereo_match.cpp sample where some reasonably good |
|
P1 and P2 values are shown (like 8\*number_of_image_channels\*SADWindowSize\*SADWindowSize and |
|
32\*number_of_image_channels\*SADWindowSize\*SADWindowSize , respectively). |
|
@param disp12MaxDiff Maximum allowed difference (in integer pixel units) in the left-right |
|
disparity check. Set it to a non-positive value to disable the check. |
|
@param preFilterCap Truncation value for the prefiltered image pixels. The algorithm first |
|
computes x-derivative at each pixel and clips its value by [-preFilterCap, preFilterCap] interval. |
|
The result values are passed to the Birchfield-Tomasi pixel cost function. |
|
@param uniquenessRatio Margin in percentage by which the best (minimum) computed cost function |
|
value should "win" the second best value to consider the found match correct. Normally, a value |
|
within the 5-15 range is good enough. |
|
@param speckleWindowSize Maximum size of smooth disparity regions to consider their noise speckles |
|
and invalidate. Set it to 0 to disable speckle filtering. Otherwise, set it somewhere in the |
|
50-200 range. |
|
@param speckleRange Maximum disparity variation within each connected component. If you do speckle |
|
filtering, set the parameter to a positive value, it will be implicitly multiplied by 16. |
|
Normally, 1 or 2 is good enough. |
|
@param mode Set it to StereoSGBM::MODE_HH to run the full-scale two-pass dynamic programming |
|
algorithm. It will consume O(W\*H\*numDisparities) bytes, which is large for 640x480 stereo and |
|
huge for HD-size pictures. By default, it is set to false . |
|
|
|
The first constructor initializes StereoSGBM with all the default parameters. So, you only have to |
|
set StereoSGBM::numDisparities at minimum. The second constructor enables you to set each parameter |
|
to a custom value. |
|
*/ |
|
CV_WRAP static Ptr<StereoSGBM> create(int minDisparity = 0, int numDisparities = 16, int blockSize = 3, |
|
int P1 = 0, int P2 = 0, int disp12MaxDiff = 0, |
|
int preFilterCap = 0, int uniquenessRatio = 0, |
|
int speckleWindowSize = 0, int speckleRange = 0, |
|
int mode = StereoSGBM::MODE_SGBM); |
|
}; |
|
|
|
|
|
//! cv::undistort mode |
|
enum UndistortTypes |
|
{ |
|
PROJ_SPHERICAL_ORTHO = 0, |
|
PROJ_SPHERICAL_EQRECT = 1 |
|
}; |
|
|
|
/** @brief Transforms an image to compensate for lens distortion. |
|
|
|
The function transforms an image to compensate radial and tangential lens distortion. |
|
|
|
The function is simply a combination of #initUndistortRectifyMap (with unity R ) and #remap |
|
(with bilinear interpolation). See the former function for details of the transformation being |
|
performed. |
|
|
|
Those pixels in the destination image, for which there is no correspondent pixels in the source |
|
image, are filled with zeros (black color). |
|
|
|
A particular subset of the source image that will be visible in the corrected image can be regulated |
|
by newCameraMatrix. You can use #getOptimalNewCameraMatrix to compute the appropriate |
|
newCameraMatrix depending on your requirements. |
|
|
|
The camera matrix and the distortion parameters can be determined using #calibrateCamera. If |
|
the resolution of images is different from the resolution used at the calibration stage, \f$f_x, |
|
f_y, c_x\f$ and \f$c_y\f$ need to be scaled accordingly, while the distortion coefficients remain |
|
the same. |
|
|
|
@param src Input (distorted) image. |
|
@param dst Output (corrected) image that has the same size and type as src . |
|
@param cameraMatrix Input camera matrix \f$A = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6[, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ |
|
of 4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are assumed. |
|
@param newCameraMatrix Camera matrix of the distorted image. By default, it is the same as |
|
cameraMatrix but you may additionally scale and shift the result by using a different matrix. |
|
*/ |
|
CV_EXPORTS_W void undistort( InputArray src, OutputArray dst, |
|
InputArray cameraMatrix, |
|
InputArray distCoeffs, |
|
InputArray newCameraMatrix = noArray() ); |
|
|
|
/** @brief Computes the undistortion and rectification transformation map. |
|
|
|
The function computes the joint undistortion and rectification transformation and represents the |
|
result in the form of maps for remap. The undistorted image looks like original, as if it is |
|
captured with a camera using the camera matrix =newCameraMatrix and zero distortion. In case of a |
|
monocular camera, newCameraMatrix is usually equal to cameraMatrix, or it can be computed by |
|
#getOptimalNewCameraMatrix for a better control over scaling. In case of a stereo camera, |
|
newCameraMatrix is normally set to P1 or P2 computed by #stereoRectify . |
|
|
|
Also, this new camera is oriented differently in the coordinate space, according to R. That, for |
|
example, helps to align two heads of a stereo camera so that the epipolar lines on both images |
|
become horizontal and have the same y- coordinate (in case of a horizontally aligned stereo camera). |
|
|
|
The function actually builds the maps for the inverse mapping algorithm that is used by remap. That |
|
is, for each pixel \f$(u, v)\f$ in the destination (corrected and rectified) image, the function |
|
computes the corresponding coordinates in the source image (that is, in the original image from |
|
camera). The following process is applied: |
|
\f[ |
|
\begin{array}{l} |
|
x \leftarrow (u - {c'}_x)/{f'}_x \\ |
|
y \leftarrow (v - {c'}_y)/{f'}_y \\ |
|
{[X\,Y\,W]} ^T \leftarrow R^{-1}*[x \, y \, 1]^T \\ |
|
x' \leftarrow X/W \\ |
|
y' \leftarrow Y/W \\ |
|
r^2 \leftarrow x'^2 + y'^2 \\ |
|
x'' \leftarrow x' \frac{1 + k_1 r^2 + k_2 r^4 + k_3 r^6}{1 + k_4 r^2 + k_5 r^4 + k_6 r^6} |
|
+ 2p_1 x' y' + p_2(r^2 + 2 x'^2) + s_1 r^2 + s_2 r^4\\ |
|
y'' \leftarrow y' \frac{1 + k_1 r^2 + k_2 r^4 + k_3 r^6}{1 + k_4 r^2 + k_5 r^4 + k_6 r^6} |
|
+ p_1 (r^2 + 2 y'^2) + 2 p_2 x' y' + s_3 r^2 + s_4 r^4 \\ |
|
s\vecthree{x'''}{y'''}{1} = |
|
\vecthreethree{R_{33}(\tau_x, \tau_y)}{0}{-R_{13}((\tau_x, \tau_y)} |
|
{0}{R_{33}(\tau_x, \tau_y)}{-R_{23}(\tau_x, \tau_y)} |
|
{0}{0}{1} R(\tau_x, \tau_y) \vecthree{x''}{y''}{1}\\ |
|
map_x(u,v) \leftarrow x''' f_x + c_x \\ |
|
map_y(u,v) \leftarrow y''' f_y + c_y |
|
\end{array} |
|
\f] |
|
where \f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6[, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ |
|
are the distortion coefficients. |
|
|
|
In case of a stereo camera, this function is called twice: once for each camera head, after |
|
stereoRectify, which in its turn is called after #stereoCalibrate. But if the stereo camera |
|
was not calibrated, it is still possible to compute the rectification transformations directly from |
|
the fundamental matrix using #stereoRectifyUncalibrated. For each camera, the function computes |
|
homography H as the rectification transformation in a pixel domain, not a rotation matrix R in 3D |
|
space. R can be computed from H as |
|
\f[\texttt{R} = \texttt{cameraMatrix} ^{-1} \cdot \texttt{H} \cdot \texttt{cameraMatrix}\f] |
|
where cameraMatrix can be chosen arbitrarily. |
|
|
|
@param cameraMatrix Input camera matrix \f$A=\vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6[, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ |
|
of 4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are assumed. |
|
@param R Optional rectification transformation in the object space (3x3 matrix). R1 or R2 , |
|
computed by #stereoRectify can be passed here. If the matrix is empty, the identity transformation |
|
is assumed. In cvInitUndistortMap R assumed to be an identity matrix. |
|
@param newCameraMatrix New camera matrix \f$A'=\vecthreethree{f_x'}{0}{c_x'}{0}{f_y'}{c_y'}{0}{0}{1}\f$. |
|
@param size Undistorted image size. |
|
@param m1type Type of the first output map that can be CV_32FC1, CV_32FC2 or CV_16SC2, see #convertMaps |
|
@param map1 The first output map. |
|
@param map2 The second output map. |
|
*/ |
|
CV_EXPORTS_W |
|
void initUndistortRectifyMap(InputArray cameraMatrix, InputArray distCoeffs, |
|
InputArray R, InputArray newCameraMatrix, |
|
Size size, int m1type, OutputArray map1, OutputArray map2); |
|
|
|
//! initializes maps for #remap for wide-angle |
|
CV_EXPORTS |
|
float initWideAngleProjMap(InputArray cameraMatrix, InputArray distCoeffs, |
|
Size imageSize, int destImageWidth, |
|
int m1type, OutputArray map1, OutputArray map2, |
|
enum UndistortTypes projType = PROJ_SPHERICAL_EQRECT, double alpha = 0); |
|
static inline |
|
float initWideAngleProjMap(InputArray cameraMatrix, InputArray distCoeffs, |
|
Size imageSize, int destImageWidth, |
|
int m1type, OutputArray map1, OutputArray map2, |
|
int projType, double alpha = 0) |
|
{ |
|
return initWideAngleProjMap(cameraMatrix, distCoeffs, imageSize, destImageWidth, |
|
m1type, map1, map2, (UndistortTypes)projType, alpha); |
|
} |
|
|
|
/** @brief Returns the default new camera matrix. |
|
|
|
The function returns the camera matrix that is either an exact copy of the input cameraMatrix (when |
|
centerPrinicipalPoint=false ), or the modified one (when centerPrincipalPoint=true). |
|
|
|
In the latter case, the new camera matrix will be: |
|
|
|
\f[\begin{bmatrix} f_x && 0 && ( \texttt{imgSize.width} -1)*0.5 \\ 0 && f_y && ( \texttt{imgSize.height} -1)*0.5 \\ 0 && 0 && 1 \end{bmatrix} ,\f] |
|
|
|
where \f$f_x\f$ and \f$f_y\f$ are \f$(0,0)\f$ and \f$(1,1)\f$ elements of cameraMatrix, respectively. |
|
|
|
By default, the undistortion functions in OpenCV (see #initUndistortRectifyMap, #undistort) do not |
|
move the principal point. However, when you work with stereo, it is important to move the principal |
|
points in both views to the same y-coordinate (which is required by most of stereo correspondence |
|
algorithms), and may be to the same x-coordinate too. So, you can form the new camera matrix for |
|
each view where the principal points are located at the center. |
|
|
|
@param cameraMatrix Input camera matrix. |
|
@param imgsize Camera view image size in pixels. |
|
@param centerPrincipalPoint Location of the principal point in the new camera matrix. The |
|
parameter indicates whether this location should be at the image center or not. |
|
*/ |
|
CV_EXPORTS_W |
|
Mat getDefaultNewCameraMatrix(InputArray cameraMatrix, Size imgsize = Size(), |
|
bool centerPrincipalPoint = false); |
|
|
|
/** @brief Computes the ideal point coordinates from the observed point coordinates. |
|
|
|
The function is similar to #undistort and #initUndistortRectifyMap but it operates on a |
|
sparse set of points instead of a raster image. Also the function performs a reverse transformation |
|
to projectPoints. In case of a 3D object, it does not reconstruct its 3D coordinates, but for a |
|
planar object, it does, up to a translation vector, if the proper R is specified. |
|
|
|
For each observed point coordinate \f$(u, v)\f$ the function computes: |
|
\f[ |
|
\begin{array}{l} |
|
x^{"} \leftarrow (u - c_x)/f_x \\ |
|
y^{"} \leftarrow (v - c_y)/f_y \\ |
|
(x',y') = undistort(x^{"},y^{"}, \texttt{distCoeffs}) \\ |
|
{[X\,Y\,W]} ^T \leftarrow R*[x' \, y' \, 1]^T \\ |
|
x \leftarrow X/W \\ |
|
y \leftarrow Y/W \\ |
|
\text{only performed if P is specified:} \\ |
|
u' \leftarrow x {f'}_x + {c'}_x \\ |
|
v' \leftarrow y {f'}_y + {c'}_y |
|
\end{array} |
|
\f] |
|
|
|
where *undistort* is an approximate iterative algorithm that estimates the normalized original |
|
point coordinates out of the normalized distorted point coordinates ("normalized" means that the |
|
coordinates do not depend on the camera matrix). |
|
|
|
The function can be used for both a stereo camera head or a monocular camera (when R is empty). |
|
|
|
@param src Observed point coordinates, 1xN or Nx1 2-channel (CV_32FC2 or CV_64FC2). |
|
@param dst Output ideal point coordinates after undistortion and reverse perspective |
|
transformation. If matrix P is identity or omitted, dst will contain normalized point coordinates. |
|
@param cameraMatrix Camera matrix \f$\vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . |
|
@param distCoeffs Input vector of distortion coefficients |
|
\f$(k_1, k_2, p_1, p_2[, k_3[, k_4, k_5, k_6[, s_1, s_2, s_3, s_4[, \tau_x, \tau_y]]]])\f$ |
|
of 4, 5, 8, 12 or 14 elements. If the vector is NULL/empty, the zero distortion coefficients are assumed. |
|
@param R Rectification transformation in the object space (3x3 matrix). R1 or R2 computed by |
|
#stereoRectify can be passed here. If the matrix is empty, the identity transformation is used. |
|
@param P New camera matrix (3x3) or new projection matrix (3x4) \f$\begin{bmatrix} {f'}_x & 0 & {c'}_x & t_x \\ 0 & {f'}_y & {c'}_y & t_y \\ 0 & 0 & 1 & t_z \end{bmatrix}\f$. P1 or P2 computed by |
|
#stereoRectify can be passed here. If the matrix is empty, the identity new camera matrix is used. |
|
*/ |
|
CV_EXPORTS_W |
|
void undistortPoints(InputArray src, OutputArray dst, |
|
InputArray cameraMatrix, InputArray distCoeffs, |
|
InputArray R = noArray(), InputArray P = noArray()); |
|
/** @overload |
|
@note Default version of #undistortPoints does 5 iterations to compute undistorted points. |
|
*/ |
|
CV_EXPORTS_AS(undistortPointsIter) |
|
void undistortPoints(InputArray src, OutputArray dst, |
|
InputArray cameraMatrix, InputArray distCoeffs, |
|
InputArray R, InputArray P, TermCriteria criteria); |
|
|
|
//! @} calib3d |
|
|
|
/** @brief The methods in this namespace use a so-called fisheye camera model. |
|
@ingroup calib3d_fisheye |
|
*/ |
|
namespace fisheye |
|
{ |
|
//! @addtogroup calib3d_fisheye |
|
//! @{ |
|
|
|
enum{ |
|
CALIB_USE_INTRINSIC_GUESS = 1 << 0, |
|
CALIB_RECOMPUTE_EXTRINSIC = 1 << 1, |
|
CALIB_CHECK_COND = 1 << 2, |
|
CALIB_FIX_SKEW = 1 << 3, |
|
CALIB_FIX_K1 = 1 << 4, |
|
CALIB_FIX_K2 = 1 << 5, |
|
CALIB_FIX_K3 = 1 << 6, |
|
CALIB_FIX_K4 = 1 << 7, |
|
CALIB_FIX_INTRINSIC = 1 << 8, |
|
CALIB_FIX_PRINCIPAL_POINT = 1 << 9 |
|
}; |
|
|
|
/** @brief Projects points using fisheye model |
|
|
|
@param objectPoints Array of object points, 1xN/Nx1 3-channel (or vector\<Point3f\> ), where N is |
|
the number of points in the view. |
|
@param imagePoints Output array of image points, 2xN/Nx2 1-channel or 1xN/Nx1 2-channel, or |
|
vector\<Point2f\>. |
|
@param affine |
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param alpha The skew coefficient. |
|
@param jacobian Optional output 2Nx15 jacobian matrix of derivatives of image points with respect |
|
to components of the focal lengths, coordinates of the principal point, distortion coefficients, |
|
rotation vector, translation vector, and the skew. In the old interface different components of |
|
the jacobian are returned via different output parameters. |
|
|
|
The function computes projections of 3D points to the image plane given intrinsic and extrinsic |
|
camera parameters. Optionally, the function computes Jacobians - matrices of partial derivatives of |
|
image points coordinates (as functions of all the input parameters) with respect to the particular |
|
parameters, intrinsic and/or extrinsic. |
|
*/ |
|
CV_EXPORTS void projectPoints(InputArray objectPoints, OutputArray imagePoints, const Affine3d& affine, |
|
InputArray K, InputArray D, double alpha = 0, OutputArray jacobian = noArray()); |
|
|
|
/** @overload */ |
|
CV_EXPORTS_W void projectPoints(InputArray objectPoints, OutputArray imagePoints, InputArray rvec, InputArray tvec, |
|
InputArray K, InputArray D, double alpha = 0, OutputArray jacobian = noArray()); |
|
|
|
/** @brief Distorts 2D points using fisheye model. |
|
|
|
@param undistorted Array of object points, 1xN/Nx1 2-channel (or vector\<Point2f\> ), where N is |
|
the number of points in the view. |
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param alpha The skew coefficient. |
|
@param distorted Output array of image points, 1xN/Nx1 2-channel, or vector\<Point2f\> . |
|
|
|
Note that the function assumes the camera matrix of the undistorted points to be identity. |
|
This means if you want to transform back points undistorted with undistortPoints() you have to |
|
multiply them with \f$P^{-1}\f$. |
|
*/ |
|
CV_EXPORTS_W void distortPoints(InputArray undistorted, OutputArray distorted, InputArray K, InputArray D, double alpha = 0); |
|
|
|
/** @brief Undistorts 2D points using fisheye model |
|
|
|
@param distorted Array of object points, 1xN/Nx1 2-channel (or vector\<Point2f\> ), where N is the |
|
number of points in the view. |
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param R Rectification transformation in the object space: 3x3 1-channel, or vector: 3x1/1x3 |
|
1-channel or 1x1 3-channel |
|
@param P New camera matrix (3x3) or new projection matrix (3x4) |
|
@param undistorted Output array of image points, 1xN/Nx1 2-channel, or vector\<Point2f\> . |
|
*/ |
|
CV_EXPORTS_W void undistortPoints(InputArray distorted, OutputArray undistorted, |
|
InputArray K, InputArray D, InputArray R = noArray(), InputArray P = noArray()); |
|
|
|
/** @brief Computes undistortion and rectification maps for image transform by cv::remap(). If D is empty zero |
|
distortion is used, if R or P is empty identity matrixes are used. |
|
|
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param R Rectification transformation in the object space: 3x3 1-channel, or vector: 3x1/1x3 |
|
1-channel or 1x1 3-channel |
|
@param P New camera matrix (3x3) or new projection matrix (3x4) |
|
@param size Undistorted image size. |
|
@param m1type Type of the first output map that can be CV_32FC1 or CV_16SC2 . See convertMaps() |
|
for details. |
|
@param map1 The first output map. |
|
@param map2 The second output map. |
|
*/ |
|
CV_EXPORTS_W void initUndistortRectifyMap(InputArray K, InputArray D, InputArray R, InputArray P, |
|
const cv::Size& size, int m1type, OutputArray map1, OutputArray map2); |
|
|
|
/** @brief Transforms an image to compensate for fisheye lens distortion. |
|
|
|
@param distorted image with fisheye lens distortion. |
|
@param undistorted Output image with compensated fisheye lens distortion. |
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param Knew Camera matrix of the distorted image. By default, it is the identity matrix but you |
|
may additionally scale and shift the result by using a different matrix. |
|
@param new_size |
|
|
|
The function transforms an image to compensate radial and tangential lens distortion. |
|
|
|
The function is simply a combination of fisheye::initUndistortRectifyMap (with unity R ) and remap |
|
(with bilinear interpolation). See the former function for details of the transformation being |
|
performed. |
|
|
|
See below the results of undistortImage. |
|
- a\) result of undistort of perspective camera model (all possible coefficients (k_1, k_2, k_3, |
|
k_4, k_5, k_6) of distortion were optimized under calibration) |
|
- b\) result of fisheye::undistortImage of fisheye camera model (all possible coefficients (k_1, k_2, |
|
k_3, k_4) of fisheye distortion were optimized under calibration) |
|
- c\) original image was captured with fisheye lens |
|
|
|
Pictures a) and b) almost the same. But if we consider points of image located far from the center |
|
of image, we can notice that on image a) these points are distorted. |
|
|
|
![image](pics/fisheye_undistorted.jpg) |
|
*/ |
|
CV_EXPORTS_W void undistortImage(InputArray distorted, OutputArray undistorted, |
|
InputArray K, InputArray D, InputArray Knew = cv::noArray(), const Size& new_size = Size()); |
|
|
|
/** @brief Estimates new camera matrix for undistortion or rectification. |
|
|
|
@param K Camera matrix \f$K = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{_1}\f$. |
|
@param image_size |
|
@param D Input vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param R Rectification transformation in the object space: 3x3 1-channel, or vector: 3x1/1x3 |
|
1-channel or 1x1 3-channel |
|
@param P New camera matrix (3x3) or new projection matrix (3x4) |
|
@param balance Sets the new focal length in range between the min focal length and the max focal |
|
length. Balance is in range of [0, 1]. |
|
@param new_size |
|
@param fov_scale Divisor for new focal length. |
|
*/ |
|
CV_EXPORTS_W void estimateNewCameraMatrixForUndistortRectify(InputArray K, InputArray D, const Size &image_size, InputArray R, |
|
OutputArray P, double balance = 0.0, const Size& new_size = Size(), double fov_scale = 1.0); |
|
|
|
/** @brief Performs camera calibaration |
|
|
|
@param objectPoints vector of vectors of calibration pattern points in the calibration pattern |
|
coordinate space. |
|
@param imagePoints vector of vectors of the projections of calibration pattern points. |
|
imagePoints.size() and objectPoints.size() and imagePoints[i].size() must be equal to |
|
objectPoints[i].size() for each i. |
|
@param image_size Size of the image used only to initialize the intrinsic camera matrix. |
|
@param K Output 3x3 floating-point camera matrix |
|
\f$A = \vecthreethree{f_x}{0}{c_x}{0}{f_y}{c_y}{0}{0}{1}\f$ . If |
|
fisheye::CALIB_USE_INTRINSIC_GUESS/ is specified, some or all of fx, fy, cx, cy must be |
|
initialized before calling the function. |
|
@param D Output vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$. |
|
@param rvecs Output vector of rotation vectors (see Rodrigues ) estimated for each pattern view. |
|
That is, each k-th rotation vector together with the corresponding k-th translation vector (see |
|
the next output parameter description) brings the calibration pattern from the model coordinate |
|
space (in which object points are specified) to the world coordinate space, that is, a real |
|
position of the calibration pattern in the k-th pattern view (k=0.. *M* -1). |
|
@param tvecs Output vector of translation vectors estimated for each pattern view. |
|
@param flags Different flags that may be zero or a combination of the following values: |
|
- **fisheye::CALIB_USE_INTRINSIC_GUESS** cameraMatrix contains valid initial values of |
|
fx, fy, cx, cy that are optimized further. Otherwise, (cx, cy) is initially set to the image |
|
center ( imageSize is used), and focal distances are computed in a least-squares fashion. |
|
- **fisheye::CALIB_RECOMPUTE_EXTRINSIC** Extrinsic will be recomputed after each iteration |
|
of intrinsic optimization. |
|
- **fisheye::CALIB_CHECK_COND** The functions will check validity of condition number. |
|
- **fisheye::CALIB_FIX_SKEW** Skew coefficient (alpha) is set to zero and stay zero. |
|
- **fisheye::CALIB_FIX_K1..fisheye::CALIB_FIX_K4** Selected distortion coefficients |
|
are set to zeros and stay zero. |
|
- **fisheye::CALIB_FIX_PRINCIPAL_POINT** The principal point is not changed during the global |
|
optimization. It stays at the center or at a different location specified when CALIB_USE_INTRINSIC_GUESS is set too. |
|
@param criteria Termination criteria for the iterative optimization algorithm. |
|
*/ |
|
CV_EXPORTS_W double calibrate(InputArrayOfArrays objectPoints, InputArrayOfArrays imagePoints, const Size& image_size, |
|
InputOutputArray K, InputOutputArray D, OutputArrayOfArrays rvecs, OutputArrayOfArrays tvecs, int flags = 0, |
|
TermCriteria criteria = TermCriteria(TermCriteria::COUNT + TermCriteria::EPS, 100, DBL_EPSILON)); |
|
|
|
/** @brief Stereo rectification for fisheye camera model |
|
|
|
@param K1 First camera matrix. |
|
@param D1 First camera distortion parameters. |
|
@param K2 Second camera matrix. |
|
@param D2 Second camera distortion parameters. |
|
@param imageSize Size of the image used for stereo calibration. |
|
@param R Rotation matrix between the coordinate systems of the first and the second |
|
cameras. |
|
@param tvec Translation vector between coordinate systems of the cameras. |
|
@param R1 Output 3x3 rectification transform (rotation matrix) for the first camera. |
|
@param R2 Output 3x3 rectification transform (rotation matrix) for the second camera. |
|
@param P1 Output 3x4 projection matrix in the new (rectified) coordinate systems for the first |
|
camera. |
|
@param P2 Output 3x4 projection matrix in the new (rectified) coordinate systems for the second |
|
camera. |
|
@param Q Output \f$4 \times 4\f$ disparity-to-depth mapping matrix (see reprojectImageTo3D ). |
|
@param flags Operation flags that may be zero or CALIB_ZERO_DISPARITY . If the flag is set, |
|
the function makes the principal points of each camera have the same pixel coordinates in the |
|
rectified views. And if the flag is not set, the function may still shift the images in the |
|
horizontal or vertical direction (depending on the orientation of epipolar lines) to maximize the |
|
useful image area. |
|
@param newImageSize New image resolution after rectification. The same size should be passed to |
|
initUndistortRectifyMap (see the stereo_calib.cpp sample in OpenCV samples directory). When (0,0) |
|
is passed (default), it is set to the original imageSize . Setting it to larger value can help you |
|
preserve details in the original image, especially when there is a big radial distortion. |
|
@param balance Sets the new focal length in range between the min focal length and the max focal |
|
length. Balance is in range of [0, 1]. |
|
@param fov_scale Divisor for new focal length. |
|
*/ |
|
CV_EXPORTS_W void stereoRectify(InputArray K1, InputArray D1, InputArray K2, InputArray D2, const Size &imageSize, InputArray R, InputArray tvec, |
|
OutputArray R1, OutputArray R2, OutputArray P1, OutputArray P2, OutputArray Q, int flags, const Size &newImageSize = Size(), |
|
double balance = 0.0, double fov_scale = 1.0); |
|
|
|
/** @brief Performs stereo calibration |
|
|
|
@param objectPoints Vector of vectors of the calibration pattern points. |
|
@param imagePoints1 Vector of vectors of the projections of the calibration pattern points, |
|
observed by the first camera. |
|
@param imagePoints2 Vector of vectors of the projections of the calibration pattern points, |
|
observed by the second camera. |
|
@param K1 Input/output first camera matrix: |
|
\f$\vecthreethree{f_x^{(j)}}{0}{c_x^{(j)}}{0}{f_y^{(j)}}{c_y^{(j)}}{0}{0}{1}\f$ , \f$j = 0,\, 1\f$ . If |
|
any of fisheye::CALIB_USE_INTRINSIC_GUESS , fisheye::CALIB_FIX_INTRINSIC are specified, |
|
some or all of the matrix components must be initialized. |
|
@param D1 Input/output vector of distortion coefficients \f$(k_1, k_2, k_3, k_4)\f$ of 4 elements. |
|
@param K2 Input/output second camera matrix. The parameter is similar to K1 . |
|
@param D2 Input/output lens distortion coefficients for the second camera. The parameter is |
|
similar to D1 . |
|
@param imageSize Size of the image used only to initialize intrinsic camera matrix. |
|
@param R Output rotation matrix between the 1st and the 2nd camera coordinate systems. |
|
@param T Output translation vector between the coordinate systems of the cameras. |
|
@param flags Different flags that may be zero or a combination of the following values: |
|
- **fisheye::CALIB_FIX_INTRINSIC** Fix K1, K2? and D1, D2? so that only R, T matrices |
|
are estimated. |
|
- **fisheye::CALIB_USE_INTRINSIC_GUESS** K1, K2 contains valid initial values of |
|
fx, fy, cx, cy that are optimized further. Otherwise, (cx, cy) is initially set to the image |
|
center (imageSize is used), and focal distances are computed in a least-squares fashion. |
|
- **fisheye::CALIB_RECOMPUTE_EXTRINSIC** Extrinsic will be recomputed after each iteration |
|
of intrinsic optimization. |
|
- **fisheye::CALIB_CHECK_COND** The functions will check validity of condition number. |
|
- **fisheye::CALIB_FIX_SKEW** Skew coefficient (alpha) is set to zero and stay zero. |
|
- **fisheye::CALIB_FIX_K1..4** Selected distortion coefficients are set to zeros and stay |
|
zero. |
|
@param criteria Termination criteria for the iterative optimization algorithm. |
|
*/ |
|
CV_EXPORTS_W double stereoCalibrate(InputArrayOfArrays objectPoints, InputArrayOfArrays imagePoints1, InputArrayOfArrays imagePoints2, |
|
InputOutputArray K1, InputOutputArray D1, InputOutputArray K2, InputOutputArray D2, Size imageSize, |
|
OutputArray R, OutputArray T, int flags = fisheye::CALIB_FIX_INTRINSIC, |
|
TermCriteria criteria = TermCriteria(TermCriteria::COUNT + TermCriteria::EPS, 100, DBL_EPSILON)); |
|
|
|
//! @} calib3d_fisheye |
|
} // end namespace fisheye |
|
|
|
} //end namespace cv |
|
|
|
#endif
|
|
|