|
|
|
@ -46,15 +46,78 @@ |
|
|
|
|
|
|
|
|
|
#include "opencv2/core.hpp" |
|
|
|
|
|
|
|
|
|
/**
|
|
|
|
|
@defgroup objdetect Object Detection |
|
|
|
|
|
|
|
|
|
Haar Feature-based Cascade Classifier for Object Detection |
|
|
|
|
---------------------------------------------------------- |
|
|
|
|
|
|
|
|
|
The object detector described below has been initially proposed by Paul Viola @cite Viola01 and |
|
|
|
|
improved by Rainer Lienhart @cite Lienhart02. |
|
|
|
|
|
|
|
|
|
First, a classifier (namely a *cascade of boosted classifiers working with haar-like features*) is |
|
|
|
|
trained with a few hundred sample views of a particular object (i.e., a face or a car), called |
|
|
|
|
positive examples, that are scaled to the same size (say, 20x20), and negative examples - arbitrary |
|
|
|
|
images of the same size. |
|
|
|
|
|
|
|
|
|
After a classifier is trained, it can be applied to a region of interest (of the same size as used |
|
|
|
|
during the training) in an input image. The classifier outputs a "1" if the region is likely to show |
|
|
|
|
the object (i.e., face/car), and "0" otherwise. To search for the object in the whole image one can |
|
|
|
|
move the search window across the image and check every location using the classifier. The |
|
|
|
|
classifier is designed so that it can be easily "resized" in order to be able to find the objects of |
|
|
|
|
interest at different sizes, which is more efficient than resizing the image itself. So, to find an |
|
|
|
|
object of an unknown size in the image the scan procedure should be done several times at different |
|
|
|
|
scales. |
|
|
|
|
|
|
|
|
|
The word "cascade" in the classifier name means that the resultant classifier consists of several |
|
|
|
|
simpler classifiers (*stages*) that are applied subsequently to a region of interest until at some |
|
|
|
|
stage the candidate is rejected or all the stages are passed. The word "boosted" means that the |
|
|
|
|
classifiers at every stage of the cascade are complex themselves and they are built out of basic |
|
|
|
|
classifiers using one of four different boosting techniques (weighted voting). Currently Discrete |
|
|
|
|
Adaboost, Real Adaboost, Gentle Adaboost and Logitboost are supported. The basic classifiers are |
|
|
|
|
decision-tree classifiers with at least 2 leaves. Haar-like features are the input to the basic |
|
|
|
|
classifiers, and are calculated as described below. The current algorithm uses the following |
|
|
|
|
Haar-like features: |
|
|
|
|
|
|
|
|
|
 |
|
|
|
|
|
|
|
|
|
The feature used in a particular classifier is specified by its shape (1a, 2b etc.), position within |
|
|
|
|
the region of interest and the scale (this scale is not the same as the scale used at the detection |
|
|
|
|
stage, though these two scales are multiplied). For example, in the case of the third line feature |
|
|
|
|
(2c) the response is calculated as the difference between the sum of image pixels under the |
|
|
|
|
rectangle covering the whole feature (including the two white stripes and the black stripe in the |
|
|
|
|
middle) and the sum of the image pixels under the black stripe multiplied by 3 in order to |
|
|
|
|
compensate for the differences in the size of areas. The sums of pixel values over a rectangular |
|
|
|
|
regions are calculated rapidly using integral images (see below and the integral description). |
|
|
|
|
|
|
|
|
|
To see the object detector at work, have a look at the facedetect demo: |
|
|
|
|
<https://github.com/Itseez/opencv/tree/master/samples/cpp/dbt_face_detection.cpp>
|
|
|
|
|
|
|
|
|
|
The following reference is for the detection part only. There is a separate application called |
|
|
|
|
opencv\_traincascade that can train a cascade of boosted classifiers from a set of samples. |
|
|
|
|
|
|
|
|
|
@note In the new C++ interface it is also possible to use LBP (local binary pattern) features in |
|
|
|
|
addition to Haar-like features. .. [Viola01] Paul Viola and Michael J. Jones. Rapid Object Detection |
|
|
|
|
using a Boosted Cascade of Simple Features. IEEE CVPR, 2001. The paper is available online at |
|
|
|
|
<http://research.microsoft.com/en-us/um/people/viola/Pubs/Detect/violaJones_CVPR2001.pdf>
|
|
|
|
|
|
|
|
|
|
@{ |
|
|
|
|
@defgroup objdetect_c C API |
|
|
|
|
@} |
|
|
|
|
*/ |
|
|
|
|
|
|
|
|
|
typedef struct CvHaarClassifierCascade CvHaarClassifierCascade; |
|
|
|
|
|
|
|
|
|
namespace cv |
|
|
|
|
{ |
|
|
|
|
|
|
|
|
|
//! @addtogroup objdetect
|
|
|
|
|
//! @{
|
|
|
|
|
|
|
|
|
|
///////////////////////////// Object Detection ////////////////////////////
|
|
|
|
|
|
|
|
|
|
// class for grouping object candidates, detected by Cascade Classifier, HOG etc.
|
|
|
|
|
// instance of the class is to be passed to cv::partition (see cxoperations.hpp)
|
|
|
|
|
//! class for grouping object candidates, detected by Cascade Classifier, HOG etc.
|
|
|
|
|
//! instance of the class is to be passed to cv::partition (see cxoperations.hpp)
|
|
|
|
|
class CV_EXPORTS SimilarRects |
|
|
|
|
{ |
|
|
|
|
public: |
|
|
|
@ -70,13 +133,32 @@ public: |
|
|
|
|
double eps; |
|
|
|
|
}; |
|
|
|
|
|
|
|
|
|
/** @brief Groups the object candidate rectangles.
|
|
|
|
|
|
|
|
|
|
@param rectList Input/output vector of rectangles. Output vector includes retained and grouped |
|
|
|
|
rectangles. (The Python list is not modified in place.) |
|
|
|
|
@param groupThreshold Minimum possible number of rectangles minus 1. The threshold is used in a |
|
|
|
|
group of rectangles to retain it. |
|
|
|
|
@param eps Relative difference between sides of the rectangles to merge them into a group. |
|
|
|
|
|
|
|
|
|
The function is a wrapper for the generic function partition . It clusters all the input rectangles |
|
|
|
|
using the rectangle equivalence criteria that combines rectangles with similar sizes and similar |
|
|
|
|
locations. The similarity is defined by eps. When eps=0 , no clustering is done at all. If |
|
|
|
|
\f$\texttt{eps}\rightarrow +\inf\f$ , all the rectangles are put in one cluster. Then, the small |
|
|
|
|
clusters containing less than or equal to groupThreshold rectangles are rejected. In each other |
|
|
|
|
cluster, the average rectangle is computed and put into the output rectangle list. |
|
|
|
|
*/ |
|
|
|
|
CV_EXPORTS void groupRectangles(std::vector<Rect>& rectList, int groupThreshold, double eps = 0.2); |
|
|
|
|
/** @overload */ |
|
|
|
|
CV_EXPORTS_W void groupRectangles(CV_IN_OUT std::vector<Rect>& rectList, CV_OUT std::vector<int>& weights, |
|
|
|
|
int groupThreshold, double eps = 0.2); |
|
|
|
|
/** @overload */ |
|
|
|
|
CV_EXPORTS void groupRectangles(std::vector<Rect>& rectList, int groupThreshold, |
|
|
|
|
double eps, std::vector<int>* weights, std::vector<double>* levelWeights ); |
|
|
|
|
/** @overload */ |
|
|
|
|
CV_EXPORTS void groupRectangles(std::vector<Rect>& rectList, std::vector<int>& rejectLevels, |
|
|
|
|
std::vector<double>& levelWeights, int groupThreshold, double eps = 0.2); |
|
|
|
|
/** @overload */ |
|
|
|
|
CV_EXPORTS void groupRectangles_meanshift(std::vector<Rect>& rectList, std::vector<double>& foundWeights, |
|
|
|
|
std::vector<double>& foundScales, |
|
|
|
|
double detectThreshold = 0.0, Size winDetSize = Size(64, 128)); |
|
|
|
@ -133,15 +215,54 @@ public: |
|
|
|
|
virtual Ptr<MaskGenerator> getMaskGenerator() = 0; |
|
|
|
|
}; |
|
|
|
|
|
|
|
|
|
/** @brief Cascade classifier class for object detection.
|
|
|
|
|
*/ |
|
|
|
|
class CV_EXPORTS_W CascadeClassifier |
|
|
|
|
{ |
|
|
|
|
public: |
|
|
|
|
CV_WRAP CascadeClassifier(); |
|
|
|
|
/** @brief Loads a classifier from a file.
|
|
|
|
|
|
|
|
|
|
@param filename Name of the file from which the classifier is loaded. |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP CascadeClassifier(const String& filename); |
|
|
|
|
~CascadeClassifier(); |
|
|
|
|
/** @brief Checks whether the classifier has been loaded.
|
|
|
|
|
*/ |
|
|
|
|
CV_WRAP bool empty() const; |
|
|
|
|
/** @brief Loads a classifier from a file.
|
|
|
|
|
|
|
|
|
|
@param filename Name of the file from which the classifier is loaded. The file may contain an old |
|
|
|
|
HAAR classifier trained by the haartraining application or a new cascade classifier trained by the |
|
|
|
|
traincascade application. |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP bool load( const String& filename ); |
|
|
|
|
/** @brief Reads a classifier from a FileStorage node.
|
|
|
|
|
|
|
|
|
|
@note The file may contain a new cascade classifier (trained traincascade application) only. |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP bool read( const FileNode& node ); |
|
|
|
|
|
|
|
|
|
/** @brief Detects objects of different sizes in the input image. The detected objects are returned as a list
|
|
|
|
|
of rectangles. |
|
|
|
|
|
|
|
|
|
@param image Matrix of the type CV\_8U containing an image where objects are detected. |
|
|
|
|
@param objects Vector of rectangles where each rectangle contains the detected object, the |
|
|
|
|
rectangles may be partially outside the original image. |
|
|
|
|
@param scaleFactor Parameter specifying how much the image size is reduced at each image scale. |
|
|
|
|
@param minNeighbors Parameter specifying how many neighbors each candidate rectangle should have |
|
|
|
|
to retain it. |
|
|
|
|
@param flags Parameter with the same meaning for an old cascade as in the function |
|
|
|
|
cvHaarDetectObjects. It is not used for a new cascade. |
|
|
|
|
@param minSize Minimum possible object size. Objects smaller than that are ignored. |
|
|
|
|
@param maxSize Maximum possible object size. Objects larger than that are ignored. |
|
|
|
|
|
|
|
|
|
The function is parallelized with the TBB library. |
|
|
|
|
|
|
|
|
|
@note |
|
|
|
|
- (Python) A face detection example using cascade classifiers can be found at |
|
|
|
|
opencv\_source\_code/samples/python2/facedetect.py |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP void detectMultiScale( InputArray image, |
|
|
|
|
CV_OUT std::vector<Rect>& objects, |
|
|
|
|
double scaleFactor = 1.1, |
|
|
|
@ -149,6 +270,21 @@ public: |
|
|
|
|
Size minSize = Size(), |
|
|
|
|
Size maxSize = Size() ); |
|
|
|
|
|
|
|
|
|
/** @overload
|
|
|
|
|
@param image Matrix of the type CV\_8U containing an image where objects are detected. |
|
|
|
|
@param objects Vector of rectangles where each rectangle contains the detected object, the |
|
|
|
|
rectangles may be partially outside the original image. |
|
|
|
|
@param numDetections Vector of detection numbers for the corresponding objects. An object's number |
|
|
|
|
of detections is the number of neighboring positively classified rectangles that were joined |
|
|
|
|
together to form the object. |
|
|
|
|
@param scaleFactor Parameter specifying how much the image size is reduced at each image scale. |
|
|
|
|
@param minNeighbors Parameter specifying how many neighbors each candidate rectangle should have |
|
|
|
|
to retain it. |
|
|
|
|
@param flags Parameter with the same meaning for an old cascade as in the function |
|
|
|
|
cvHaarDetectObjects. It is not used for a new cascade. |
|
|
|
|
@param minSize Minimum possible object size. Objects smaller than that are ignored. |
|
|
|
|
@param maxSize Maximum possible object size. Objects larger than that are ignored. |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP_AS(detectMultiScale2) void detectMultiScale( InputArray image, |
|
|
|
|
CV_OUT std::vector<Rect>& objects, |
|
|
|
|
CV_OUT std::vector<int>& numDetections, |
|
|
|
@ -157,6 +293,9 @@ public: |
|
|
|
|
Size minSize=Size(), |
|
|
|
|
Size maxSize=Size() ); |
|
|
|
|
|
|
|
|
|
/** @overload
|
|
|
|
|
if `outputRejectLevels` is `true` returns `rejectLevels` and `levelWeights` |
|
|
|
|
*/ |
|
|
|
|
CV_WRAP_AS(detectMultiScale3) void detectMultiScale( InputArray image, |
|
|
|
|
CV_OUT std::vector<Rect>& objects, |
|
|
|
|
CV_OUT std::vector<int>& rejectLevels, |
|
|
|
@ -184,14 +323,14 @@ CV_EXPORTS Ptr<BaseCascadeClassifier::MaskGenerator> createFaceDetectionMaskGene |
|
|
|
|
|
|
|
|
|
//////////////// HOG (Histogram-of-Oriented-Gradients) Descriptor and Object Detector //////////////
|
|
|
|
|
|
|
|
|
|
// struct for detection region of interest (ROI)
|
|
|
|
|
//! struct for detection region of interest (ROI)
|
|
|
|
|
struct DetectionROI |
|
|
|
|
{ |
|
|
|
|
// scale(size) of the bounding box
|
|
|
|
|
//! scale(size) of the bounding box
|
|
|
|
|
double scale; |
|
|
|
|
// set of requrested locations to be evaluated
|
|
|
|
|
//! set of requrested locations to be evaluated
|
|
|
|
|
std::vector<cv::Point> locations; |
|
|
|
|
// vector that will contain confidence values for each location
|
|
|
|
|
//! vector that will contain confidence values for each location
|
|
|
|
|
std::vector<double> confidences; |
|
|
|
|
}; |
|
|
|
|
|
|
|
|
@ -250,24 +389,24 @@ public: |
|
|
|
|
Size winStride = Size(), Size padding = Size(), |
|
|
|
|
const std::vector<Point>& locations = std::vector<Point>()) const; |
|
|
|
|
|
|
|
|
|
//with found weights output
|
|
|
|
|
//! with found weights output
|
|
|
|
|
CV_WRAP virtual void detect(const Mat& img, CV_OUT std::vector<Point>& foundLocations, |
|
|
|
|
CV_OUT std::vector<double>& weights, |
|
|
|
|
double hitThreshold = 0, Size winStride = Size(), |
|
|
|
|
Size padding = Size(), |
|
|
|
|
const std::vector<Point>& searchLocations = std::vector<Point>()) const; |
|
|
|
|
//without found weights output
|
|
|
|
|
//! without found weights output
|
|
|
|
|
virtual void detect(const Mat& img, CV_OUT std::vector<Point>& foundLocations, |
|
|
|
|
double hitThreshold = 0, Size winStride = Size(), |
|
|
|
|
Size padding = Size(), |
|
|
|
|
const std::vector<Point>& searchLocations=std::vector<Point>()) const; |
|
|
|
|
|
|
|
|
|
//with result weights output
|
|
|
|
|
//! with result weights output
|
|
|
|
|
CV_WRAP virtual void detectMultiScale(InputArray img, CV_OUT std::vector<Rect>& foundLocations, |
|
|
|
|
CV_OUT std::vector<double>& foundWeights, double hitThreshold = 0, |
|
|
|
|
Size winStride = Size(), Size padding = Size(), double scale = 1.05, |
|
|
|
|
double finalThreshold = 2.0,bool useMeanshiftGrouping = false) const; |
|
|
|
|
//without found weights output
|
|
|
|
|
//! without found weights output
|
|
|
|
|
virtual void detectMultiScale(InputArray img, CV_OUT std::vector<Rect>& foundLocations, |
|
|
|
|
double hitThreshold = 0, Size winStride = Size(), |
|
|
|
|
Size padding = Size(), double scale = 1.05, |
|
|
|
@ -295,24 +434,26 @@ public: |
|
|
|
|
CV_PROP int nlevels; |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
// evaluate specified ROI and return confidence value for each location
|
|
|
|
|
//! evaluate specified ROI and return confidence value for each location
|
|
|
|
|
virtual void detectROI(const cv::Mat& img, const std::vector<cv::Point> &locations, |
|
|
|
|
CV_OUT std::vector<cv::Point>& foundLocations, CV_OUT std::vector<double>& confidences, |
|
|
|
|
double hitThreshold = 0, cv::Size winStride = Size(), |
|
|
|
|
cv::Size padding = Size()) const; |
|
|
|
|
|
|
|
|
|
// evaluate specified ROI and return confidence value for each location in multiple scales
|
|
|
|
|
//! evaluate specified ROI and return confidence value for each location in multiple scales
|
|
|
|
|
virtual void detectMultiScaleROI(const cv::Mat& img, |
|
|
|
|
CV_OUT std::vector<cv::Rect>& foundLocations, |
|
|
|
|
std::vector<DetectionROI>& locations, |
|
|
|
|
double hitThreshold = 0, |
|
|
|
|
int groupThreshold = 0) const; |
|
|
|
|
|
|
|
|
|
// read/parse Dalal's alt model file
|
|
|
|
|
//! read/parse Dalal's alt model file
|
|
|
|
|
void readALTModel(String modelfile); |
|
|
|
|
void groupRectangles(std::vector<cv::Rect>& rectList, std::vector<double>& weights, int groupThreshold, double eps) const; |
|
|
|
|
}; |
|
|
|
|
|
|
|
|
|
//! @} objdetect
|
|
|
|
|
|
|
|
|
|
} |
|
|
|
|
|
|
|
|
|
#include "opencv2/objdetect/detection_based_tracker.hpp" |
|
|
|
|