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# ifndef OPENCV_VIDEOIO_HPP
# define OPENCV_VIDEOIO_HPP
# include "opencv2/core.hpp"
/**
@ defgroup videoio Video I / O
@ brief Read and write video or images sequence with OpenCV
# ## See also:
- @ ref videoio_overview
- Tutorials : @ ref tutorial_table_of_content_videoio
@ {
@ defgroup videoio_flags_base Flags for video I / O
@ defgroup videoio_flags_others Additional flags for video I / O API backends
@ defgroup videoio_c C API for video I / O
@ defgroup videoio_ios iOS glue for video I / O
@ defgroup videoio_winrt WinRT glue for video I / O
@ defgroup videoio_registry Query I / O API backends registry
@ }
*/
////////////////////////////////// video io /////////////////////////////////
typedef struct CvCapture CvCapture ;
typedef struct CvVideoWriter CvVideoWriter ;
namespace cv
{
//! @addtogroup videoio
//! @{
//! @addtogroup videoio_flags_base
//! @{
/** @brief %VideoCapture API backends identifier.
Select preferred API for a capture object .
To be used in the VideoCapture : : VideoCapture ( ) constructor or VideoCapture : : open ( )
@ note Backends are available only if they have been built with your OpenCV binaries .
See @ ref videoio_overview for more information .
*/
enum VideoCaptureAPIs {
CAP_ANY = 0 , //!< Auto detect == 0
CAP_VFW = 200 , //!< Video For Windows (platform native)
CAP_V4L = 200 , //!< V4L/V4L2 capturing support via libv4l
CAP_V4L2 = CAP_V4L , //!< Same as CAP_V4L
CAP_FIREWIRE = 300 , //!< IEEE 1394 drivers
CAP_FIREWARE = CAP_FIREWIRE , //!< Same as CAP_FIREWIRE
CAP_IEEE1394 = CAP_FIREWIRE , //!< Same as CAP_FIREWIRE
CAP_DC1394 = CAP_FIREWIRE , //!< Same as CAP_FIREWIRE
CAP_CMU1394 = CAP_FIREWIRE , //!< Same as CAP_FIREWIRE
CAP_QT = 500 , //!< QuickTime
CAP_UNICAP = 600 , //!< Unicap drivers
CAP_DSHOW = 700 , //!< DirectShow (via videoInput)
CAP_PVAPI = 800 , //!< PvAPI, Prosilica GigE SDK
CAP_OPENNI = 900 , //!< OpenNI (for Kinect)
CAP_OPENNI_ASUS = 910 , //!< OpenNI (for Asus Xtion)
CAP_ANDROID = 1000 , //!< Android - not used
CAP_XIAPI = 1100 , //!< XIMEA Camera API
CAP_AVFOUNDATION = 1200 , //!< AVFoundation framework for iOS (OS X Lion will have the same API)
CAP_GIGANETIX = 1300 , //!< Smartek Giganetix GigEVisionSDK
CAP_MSMF = 1400 , //!< Microsoft Media Foundation (via videoInput)
CAP_WINRT = 1410 , //!< Microsoft Windows Runtime using Media Foundation
CAP_INTELPERC = 1500 , //!< Intel Perceptual Computing SDK
CAP_OPENNI2 = 1600 , //!< OpenNI2 (for Kinect)
CAP_OPENNI2_ASUS = 1610 , //!< OpenNI2 (for Asus Xtion and Occipital Structure sensors)
CAP_GPHOTO2 = 1700 , //!< gPhoto2 connection
CAP_GSTREAMER = 1800 , //!< GStreamer
CAP_FFMPEG = 1900 , //!< Open and record video file or stream using the FFMPEG library
CAP_IMAGES = 2000 , //!< OpenCV Image Sequence (e.g. img_%02d.jpg)
CAP_ARAVIS = 2100 , //!< Aravis SDK
CAP_OPENCV_MJPEG = 2200 , //!< Built-in OpenCV MotionJPEG codec
CAP_INTEL_MFX = 2300 , //!< Intel MediaSDK
CAP_XINE = 2400 , //!< XINE engine (Linux)
} ;
/** @brief %VideoCapture generic properties identifier.
Reading / writing properties involves many layers . Some unexpected result might happens along this chain .
Effective behaviour depends from device hardware , driver and API Backend .
@ sa videoio_flags_others , VideoCapture : : get ( ) , VideoCapture : : set ( )
*/
enum VideoCaptureProperties {
CAP_PROP_POS_MSEC = 0 , //!< Current position of the video file in milliseconds.
CAP_PROP_POS_FRAMES = 1 , //!< 0-based index of the frame to be decoded/captured next.
CAP_PROP_POS_AVI_RATIO = 2 , //!< Relative position of the video file: 0=start of the film, 1=end of the film.
CAP_PROP_FRAME_WIDTH = 3 , //!< Width of the frames in the video stream.
CAP_PROP_FRAME_HEIGHT = 4 , //!< Height of the frames in the video stream.
CAP_PROP_FPS = 5 , //!< Frame rate.
CAP_PROP_FOURCC = 6 , //!< 4-character code of codec. see VideoWriter::fourcc .
CAP_PROP_FRAME_COUNT = 7 , //!< Number of frames in the video file.
CAP_PROP_FORMAT = 8 , //!< Format of the %Mat objects (see Mat::type()) returned by VideoCapture::retrieve().
//!< Set value -1 to fetch undecoded RAW video streams (as Mat 8UC1).
CAP_PROP_MODE = 9 , //!< Backend-specific value indicating the current capture mode.
CAP_PROP_BRIGHTNESS = 10 , //!< Brightness of the image (only for those cameras that support).
CAP_PROP_CONTRAST = 11 , //!< Contrast of the image (only for cameras).
CAP_PROP_SATURATION = 12 , //!< Saturation of the image (only for cameras).
CAP_PROP_HUE = 13 , //!< Hue of the image (only for cameras).
CAP_PROP_GAIN = 14 , //!< Gain of the image (only for those cameras that support).
CAP_PROP_EXPOSURE = 15 , //!< Exposure (only for those cameras that support).
CAP_PROP_CONVERT_RGB = 16 , //!< Boolean flags indicating whether images should be converted to RGB. <br/>
//!< *GStreamer note*: The flag is ignored in case if custom pipeline is used. It's user responsibility to interpret pipeline output.
CAP_PROP_WHITE_BALANCE_BLUE_U = 17 , //!< Currently unsupported.
CAP_PROP_RECTIFICATION = 18 , //!< Rectification flag for stereo cameras (note: only supported by DC1394 v 2.x backend currently).
CAP_PROP_MONOCHROME = 19 ,
CAP_PROP_SHARPNESS = 20 ,
CAP_PROP_AUTO_EXPOSURE = 21 , //!< DC1394: exposure control done by camera, user can adjust reference level using this feature.
CAP_PROP_GAMMA = 22 ,
CAP_PROP_TEMPERATURE = 23 ,
CAP_PROP_TRIGGER = 24 ,
CAP_PROP_TRIGGER_DELAY = 25 ,
CAP_PROP_WHITE_BALANCE_RED_V = 26 ,
CAP_PROP_ZOOM = 27 ,
CAP_PROP_FOCUS = 28 ,
CAP_PROP_GUID = 29 ,
CAP_PROP_ISO_SPEED = 30 ,
CAP_PROP_BACKLIGHT = 32 ,
CAP_PROP_PAN = 33 ,
CAP_PROP_TILT = 34 ,
CAP_PROP_ROLL = 35 ,
CAP_PROP_IRIS = 36 ,
CAP_PROP_SETTINGS = 37 , //!< Pop up video/camera filter dialog (note: only supported by DSHOW backend currently. The property value is ignored)
CAP_PROP_BUFFERSIZE = 38 ,
CAP_PROP_AUTOFOCUS = 39 ,
CAP_PROP_SAR_NUM = 40 , //!< Sample aspect ratio: num/den (num)
CAP_PROP_SAR_DEN = 41 , //!< Sample aspect ratio: num/den (den)
CAP_PROP_BACKEND = 42 , //!< Current backend (enum VideoCaptureAPIs). Read-only property
CAP_PROP_CHANNEL = 43 , //!< Video input or Channel Number (only for those cameras that support)
CAP_PROP_AUTO_WB = 44 , //!< enable/ disable auto white-balance
CAP_PROP_WB_TEMPERATURE = 45 , //!< white-balance color temperature
CAP_PROP_CODEC_PIXEL_FORMAT = 46 , //!< (read-only) codec's pixel format. 4-character code - see VideoWriter::fourcc . Subset of [AV_PIX_FMT_*](https://github.com/FFmpeg/FFmpeg/blob/master/libavcodec/raw.c) or -1 if unknown
CAP_PROP_BITRATE = 47 , //!< (read-only) Video bitrate in kbits/s
CAP_PROP_ORIENTATION_META = 48 , //!< (read-only) Frame rotation defined by stream meta (applicable for FFmpeg back-end only)
CAP_PROP_ORIENTATION_AUTO = 49 , //!< if true - rotates output frames of CvCapture considering video file's metadata (applicable for FFmpeg back-end only) (https://github.com/opencv/opencv/issues/15499)
# ifndef CV_DOXYGEN
CV__CAP_PROP_LATEST
# endif
} ;
/** @brief Generic camera output modes identifier.
@ note Currently , these are supported through the libv4l backend only .
*/
enum VideoCaptureModes {
CAP_MODE_BGR = 0 , //!< BGR24 (default)
CAP_MODE_RGB = 1 , //!< RGB24
CAP_MODE_GRAY = 2 , //!< Y8
CAP_MODE_YUYV = 3 //!< YUYV
} ;
/** @brief %VideoWriter generic properties identifier.
@ sa VideoWriter : : get ( ) , VideoWriter : : set ( )
*/
enum VideoWriterProperties {
VIDEOWRITER_PROP_QUALITY = 1 , //!< Current quality (0..100%) of the encoded videostream. Can be adjusted dynamically in some codecs.
VIDEOWRITER_PROP_FRAMEBYTES = 2 , //!< (Read-only): Size of just encoded video frame. Note that the encoding order may be different from representation order.
VIDEOWRITER_PROP_NSTRIPES = 3 //!< Number of stripes for parallel encoding. -1 for auto detection.
} ;
//! @} videoio_flags_base
//! @addtogroup videoio_flags_others
//! @{
/** @name IEEE 1394 drivers
@ {
*/
/** @brief Modes of the IEEE 1394 controlling registers
( can be : auto , manual , auto single push , absolute Latter allowed with any other mode )
every feature can have only one mode turned on at a time
*/
enum { CAP_PROP_DC1394_OFF = - 4 , //!< turn the feature off (not controlled manually nor automatically).
CAP_PROP_DC1394_MODE_MANUAL = - 3 , //!< set automatically when a value of the feature is set by the user.
CAP_PROP_DC1394_MODE_AUTO = - 2 ,
CAP_PROP_DC1394_MODE_ONE_PUSH_AUTO = - 1 ,
CAP_PROP_DC1394_MAX = 31
} ;
//! @} IEEE 1394 drivers
/** @name OpenNI (for Kinect)
@ {
*/
//! OpenNI map generators
enum { CAP_OPENNI_DEPTH_GENERATOR = 1 < < 31 ,
CAP_OPENNI_IMAGE_GENERATOR = 1 < < 30 ,
CAP_OPENNI_IR_GENERATOR = 1 < < 29 ,
CAP_OPENNI_GENERATORS_MASK = CAP_OPENNI_DEPTH_GENERATOR + CAP_OPENNI_IMAGE_GENERATOR + CAP_OPENNI_IR_GENERATOR
} ;
//! Properties of cameras available through OpenNI backend
enum { CAP_PROP_OPENNI_OUTPUT_MODE = 100 ,
CAP_PROP_OPENNI_FRAME_MAX_DEPTH = 101 , //!< In mm
CAP_PROP_OPENNI_BASELINE = 102 , //!< In mm
CAP_PROP_OPENNI_FOCAL_LENGTH = 103 , //!< In pixels
CAP_PROP_OPENNI_REGISTRATION = 104 , //!< Flag that synchronizes the remapping depth map to image map
//!< by changing depth generator's view point (if the flag is "on") or
//!< sets this view point to its normal one (if the flag is "off").
CAP_PROP_OPENNI_REGISTRATION_ON = CAP_PROP_OPENNI_REGISTRATION ,
CAP_PROP_OPENNI_APPROX_FRAME_SYNC = 105 ,
CAP_PROP_OPENNI_MAX_BUFFER_SIZE = 106 ,
CAP_PROP_OPENNI_CIRCLE_BUFFER = 107 ,
CAP_PROP_OPENNI_MAX_TIME_DURATION = 108 ,
CAP_PROP_OPENNI_GENERATOR_PRESENT = 109 ,
CAP_PROP_OPENNI2_SYNC = 110 ,
CAP_PROP_OPENNI2_MIRROR = 111
} ;
//! OpenNI shortcuts
enum { CAP_OPENNI_IMAGE_GENERATOR_PRESENT = CAP_OPENNI_IMAGE_GENERATOR + CAP_PROP_OPENNI_GENERATOR_PRESENT ,
CAP_OPENNI_IMAGE_GENERATOR_OUTPUT_MODE = CAP_OPENNI_IMAGE_GENERATOR + CAP_PROP_OPENNI_OUTPUT_MODE ,
CAP_OPENNI_DEPTH_GENERATOR_PRESENT = CAP_OPENNI_DEPTH_GENERATOR + CAP_PROP_OPENNI_GENERATOR_PRESENT ,
CAP_OPENNI_DEPTH_GENERATOR_BASELINE = CAP_OPENNI_DEPTH_GENERATOR + CAP_PROP_OPENNI_BASELINE ,
CAP_OPENNI_DEPTH_GENERATOR_FOCAL_LENGTH = CAP_OPENNI_DEPTH_GENERATOR + CAP_PROP_OPENNI_FOCAL_LENGTH ,
CAP_OPENNI_DEPTH_GENERATOR_REGISTRATION = CAP_OPENNI_DEPTH_GENERATOR + CAP_PROP_OPENNI_REGISTRATION ,
CAP_OPENNI_DEPTH_GENERATOR_REGISTRATION_ON = CAP_OPENNI_DEPTH_GENERATOR_REGISTRATION ,
CAP_OPENNI_IR_GENERATOR_PRESENT = CAP_OPENNI_IR_GENERATOR + CAP_PROP_OPENNI_GENERATOR_PRESENT ,
} ;
//! OpenNI data given from depth generator
enum { CAP_OPENNI_DEPTH_MAP = 0 , //!< Depth values in mm (CV_16UC1)
CAP_OPENNI_POINT_CLOUD_MAP = 1 , //!< XYZ in meters (CV_32FC3)
CAP_OPENNI_DISPARITY_MAP = 2 , //!< Disparity in pixels (CV_8UC1)
CAP_OPENNI_DISPARITY_MAP_32F = 3 , //!< Disparity in pixels (CV_32FC1)
CAP_OPENNI_VALID_DEPTH_MASK = 4 , //!< CV_8UC1
CAP_OPENNI_BGR_IMAGE = 5 , //!< Data given from RGB image generator
CAP_OPENNI_GRAY_IMAGE = 6 , //!< Data given from RGB image generator
CAP_OPENNI_IR_IMAGE = 7 //!< Data given from IR image generator
} ;
//! Supported output modes of OpenNI image generator
enum { CAP_OPENNI_VGA_30HZ = 0 ,
CAP_OPENNI_SXGA_15HZ = 1 ,
CAP_OPENNI_SXGA_30HZ = 2 ,
CAP_OPENNI_QVGA_30HZ = 3 ,
CAP_OPENNI_QVGA_60HZ = 4
} ;
//! @} OpenNI
/** @name GStreamer
@ {
*/
enum { CAP_PROP_GSTREAMER_QUEUE_LENGTH = 200 //!< Default is 1
} ;
//! @} GStreamer
/** @name PvAPI, Prosilica GigE SDK
@ {
*/
//! PVAPI
enum { CAP_PROP_PVAPI_MULTICASTIP = 300 , //!< IP for enable multicast master mode. 0 for disable multicast.
CAP_PROP_PVAPI_FRAMESTARTTRIGGERMODE = 301 , //!< FrameStartTriggerMode: Determines how a frame is initiated.
CAP_PROP_PVAPI_DECIMATIONHORIZONTAL = 302 , //!< Horizontal sub-sampling of the image.
CAP_PROP_PVAPI_DECIMATIONVERTICAL = 303 , //!< Vertical sub-sampling of the image.
CAP_PROP_PVAPI_BINNINGX = 304 , //!< Horizontal binning factor.
CAP_PROP_PVAPI_BINNINGY = 305 , //!< Vertical binning factor.
CAP_PROP_PVAPI_PIXELFORMAT = 306 //!< Pixel format.
} ;
//! PVAPI: FrameStartTriggerMode
enum { CAP_PVAPI_FSTRIGMODE_FREERUN = 0 , //!< Freerun
CAP_PVAPI_FSTRIGMODE_SYNCIN1 = 1 , //!< SyncIn1
CAP_PVAPI_FSTRIGMODE_SYNCIN2 = 2 , //!< SyncIn2
CAP_PVAPI_FSTRIGMODE_FIXEDRATE = 3 , //!< FixedRate
CAP_PVAPI_FSTRIGMODE_SOFTWARE = 4 //!< Software
} ;
//! PVAPI: DecimationHorizontal, DecimationVertical
enum { CAP_PVAPI_DECIMATION_OFF = 1 , //!< Off
CAP_PVAPI_DECIMATION_2OUTOF4 = 2 , //!< 2 out of 4 decimation
CAP_PVAPI_DECIMATION_2OUTOF8 = 4 , //!< 2 out of 8 decimation
CAP_PVAPI_DECIMATION_2OUTOF16 = 8 //!< 2 out of 16 decimation
} ;
//! PVAPI: PixelFormat
enum { CAP_PVAPI_PIXELFORMAT_MONO8 = 1 , //!< Mono8
CAP_PVAPI_PIXELFORMAT_MONO16 = 2 , //!< Mono16
CAP_PVAPI_PIXELFORMAT_BAYER8 = 3 , //!< Bayer8
CAP_PVAPI_PIXELFORMAT_BAYER16 = 4 , //!< Bayer16
CAP_PVAPI_PIXELFORMAT_RGB24 = 5 , //!< Rgb24
CAP_PVAPI_PIXELFORMAT_BGR24 = 6 , //!< Bgr24
CAP_PVAPI_PIXELFORMAT_RGBA32 = 7 , //!< Rgba32
CAP_PVAPI_PIXELFORMAT_BGRA32 = 8 , //!< Bgra32
} ;
//! @} PvAPI
/** @name XIMEA Camera API
@ {
*/
//! Properties of cameras available through XIMEA SDK backend
enum { CAP_PROP_XI_DOWNSAMPLING = 400 , //!< Change image resolution by binning or skipping.
CAP_PROP_XI_DATA_FORMAT = 401 , //!< Output data format.
CAP_PROP_XI_OFFSET_X = 402 , //!< Horizontal offset from the origin to the area of interest (in pixels).
CAP_PROP_XI_OFFSET_Y = 403 , //!< Vertical offset from the origin to the area of interest (in pixels).
CAP_PROP_XI_TRG_SOURCE = 404 , //!< Defines source of trigger.
CAP_PROP_XI_TRG_SOFTWARE = 405 , //!< Generates an internal trigger. PRM_TRG_SOURCE must be set to TRG_SOFTWARE.
CAP_PROP_XI_GPI_SELECTOR = 406 , //!< Selects general purpose input.
CAP_PROP_XI_GPI_MODE = 407 , //!< Set general purpose input mode.
CAP_PROP_XI_GPI_LEVEL = 408 , //!< Get general purpose level.
CAP_PROP_XI_GPO_SELECTOR = 409 , //!< Selects general purpose output.
CAP_PROP_XI_GPO_MODE = 410 , //!< Set general purpose output mode.
CAP_PROP_XI_LED_SELECTOR = 411 , //!< Selects camera signalling LED.
CAP_PROP_XI_LED_MODE = 412 , //!< Define camera signalling LED functionality.
CAP_PROP_XI_MANUAL_WB = 413 , //!< Calculates White Balance(must be called during acquisition).
CAP_PROP_XI_AUTO_WB = 414 , //!< Automatic white balance.
CAP_PROP_XI_AEAG = 415 , //!< Automatic exposure/gain.
CAP_PROP_XI_EXP_PRIORITY = 416 , //!< Exposure priority (0.5 - exposure 50%, gain 50%).
CAP_PROP_XI_AE_MAX_LIMIT = 417 , //!< Maximum limit of exposure in AEAG procedure.
CAP_PROP_XI_AG_MAX_LIMIT = 418 , //!< Maximum limit of gain in AEAG procedure.
CAP_PROP_XI_AEAG_LEVEL = 419 , //!< Average intensity of output signal AEAG should achieve(in %).
CAP_PROP_XI_TIMEOUT = 420 , //!< Image capture timeout in milliseconds.
CAP_PROP_XI_EXPOSURE = 421 , //!< Exposure time in microseconds.
CAP_PROP_XI_EXPOSURE_BURST_COUNT = 422 , //!< Sets the number of times of exposure in one frame.
CAP_PROP_XI_GAIN_SELECTOR = 423 , //!< Gain selector for parameter Gain allows to select different type of gains.
CAP_PROP_XI_GAIN = 424 , //!< Gain in dB.
CAP_PROP_XI_DOWNSAMPLING_TYPE = 426 , //!< Change image downsampling type.
CAP_PROP_XI_BINNING_SELECTOR = 427 , //!< Binning engine selector.
CAP_PROP_XI_BINNING_VERTICAL = 428 , //!< Vertical Binning - number of vertical photo-sensitive cells to combine together.
CAP_PROP_XI_BINNING_HORIZONTAL = 429 , //!< Horizontal Binning - number of horizontal photo-sensitive cells to combine together.
CAP_PROP_XI_BINNING_PATTERN = 430 , //!< Binning pattern type.
CAP_PROP_XI_DECIMATION_SELECTOR = 431 , //!< Decimation engine selector.
CAP_PROP_XI_DECIMATION_VERTICAL = 432 , //!< Vertical Decimation - vertical sub-sampling of the image - reduces the vertical resolution of the image by the specified vertical decimation factor.
CAP_PROP_XI_DECIMATION_HORIZONTAL = 433 , //!< Horizontal Decimation - horizontal sub-sampling of the image - reduces the horizontal resolution of the image by the specified vertical decimation factor.
CAP_PROP_XI_DECIMATION_PATTERN = 434 , //!< Decimation pattern type.
CAP_PROP_XI_TEST_PATTERN_GENERATOR_SELECTOR = 587 , //!< Selects which test pattern generator is controlled by the TestPattern feature.
CAP_PROP_XI_TEST_PATTERN = 588 , //!< Selects which test pattern type is generated by the selected generator.
CAP_PROP_XI_IMAGE_DATA_FORMAT = 435 , //!< Output data format.
CAP_PROP_XI_SHUTTER_TYPE = 436 , //!< Change sensor shutter type(CMOS sensor).
CAP_PROP_XI_SENSOR_TAPS = 437 , //!< Number of taps.
CAP_PROP_XI_AEAG_ROI_OFFSET_X = 439 , //!< Automatic exposure/gain ROI offset X.
CAP_PROP_XI_AEAG_ROI_OFFSET_Y = 440 , //!< Automatic exposure/gain ROI offset Y.
CAP_PROP_XI_AEAG_ROI_WIDTH = 441 , //!< Automatic exposure/gain ROI Width.
CAP_PROP_XI_AEAG_ROI_HEIGHT = 442 , //!< Automatic exposure/gain ROI Height.
CAP_PROP_XI_BPC = 445 , //!< Correction of bad pixels.
CAP_PROP_XI_WB_KR = 448 , //!< White balance red coefficient.
CAP_PROP_XI_WB_KG = 449 , //!< White balance green coefficient.
CAP_PROP_XI_WB_KB = 450 , //!< White balance blue coefficient.
CAP_PROP_XI_WIDTH = 451 , //!< Width of the Image provided by the device (in pixels).
CAP_PROP_XI_HEIGHT = 452 , //!< Height of the Image provided by the device (in pixels).
CAP_PROP_XI_REGION_SELECTOR = 589 , //!< Selects Region in Multiple ROI which parameters are set by width, height, ... ,region mode.
CAP_PROP_XI_REGION_MODE = 595 , //!< Activates/deactivates Region selected by Region Selector.
CAP_PROP_XI_LIMIT_BANDWIDTH = 459 , //!< Set/get bandwidth(datarate)(in Megabits).
CAP_PROP_XI_SENSOR_DATA_BIT_DEPTH = 460 , //!< Sensor output data bit depth.
CAP_PROP_XI_OUTPUT_DATA_BIT_DEPTH = 461 , //!< Device output data bit depth.
CAP_PROP_XI_IMAGE_DATA_BIT_DEPTH = 462 , //!< bitdepth of data returned by function xiGetImage.
CAP_PROP_XI_OUTPUT_DATA_PACKING = 463 , //!< Device output data packing (or grouping) enabled. Packing could be enabled if output_data_bit_depth > 8 and packing capability is available.
CAP_PROP_XI_OUTPUT_DATA_PACKING_TYPE = 464 , //!< Data packing type. Some cameras supports only specific packing type.
CAP_PROP_XI_IS_COOLED = 465 , //!< Returns 1 for cameras that support cooling.
CAP_PROP_XI_COOLING = 466 , //!< Start camera cooling.
CAP_PROP_XI_TARGET_TEMP = 467 , //!< Set sensor target temperature for cooling.
CAP_PROP_XI_CHIP_TEMP = 468 , //!< Camera sensor temperature.
CAP_PROP_XI_HOUS_TEMP = 469 , //!< Camera housing temperature.
CAP_PROP_XI_HOUS_BACK_SIDE_TEMP = 590 , //!< Camera housing back side temperature.
CAP_PROP_XI_SENSOR_BOARD_TEMP = 596 , //!< Camera sensor board temperature.
CAP_PROP_XI_CMS = 470 , //!< Mode of color management system.
CAP_PROP_XI_APPLY_CMS = 471 , //!< Enable applying of CMS profiles to xiGetImage (see XI_PRM_INPUT_CMS_PROFILE, XI_PRM_OUTPUT_CMS_PROFILE).
CAP_PROP_XI_IMAGE_IS_COLOR = 474 , //!< Returns 1 for color cameras.
CAP_PROP_XI_COLOR_FILTER_ARRAY = 475 , //!< Returns color filter array type of RAW data.
CAP_PROP_XI_GAMMAY = 476 , //!< Luminosity gamma.
CAP_PROP_XI_GAMMAC = 477 , //!< Chromaticity gamma.
CAP_PROP_XI_SHARPNESS = 478 , //!< Sharpness Strength.
CAP_PROP_XI_CC_MATRIX_00 = 479 , //!< Color Correction Matrix element [0][0].
CAP_PROP_XI_CC_MATRIX_01 = 480 , //!< Color Correction Matrix element [0][1].
CAP_PROP_XI_CC_MATRIX_02 = 481 , //!< Color Correction Matrix element [0][2].
CAP_PROP_XI_CC_MATRIX_03 = 482 , //!< Color Correction Matrix element [0][3].
CAP_PROP_XI_CC_MATRIX_10 = 483 , //!< Color Correction Matrix element [1][0].
CAP_PROP_XI_CC_MATRIX_11 = 484 , //!< Color Correction Matrix element [1][1].
CAP_PROP_XI_CC_MATRIX_12 = 485 , //!< Color Correction Matrix element [1][2].
CAP_PROP_XI_CC_MATRIX_13 = 486 , //!< Color Correction Matrix element [1][3].
CAP_PROP_XI_CC_MATRIX_20 = 487 , //!< Color Correction Matrix element [2][0].
CAP_PROP_XI_CC_MATRIX_21 = 488 , //!< Color Correction Matrix element [2][1].
CAP_PROP_XI_CC_MATRIX_22 = 489 , //!< Color Correction Matrix element [2][2].
CAP_PROP_XI_CC_MATRIX_23 = 490 , //!< Color Correction Matrix element [2][3].
CAP_PROP_XI_CC_MATRIX_30 = 491 , //!< Color Correction Matrix element [3][0].
CAP_PROP_XI_CC_MATRIX_31 = 492 , //!< Color Correction Matrix element [3][1].
CAP_PROP_XI_CC_MATRIX_32 = 493 , //!< Color Correction Matrix element [3][2].
CAP_PROP_XI_CC_MATRIX_33 = 494 , //!< Color Correction Matrix element [3][3].
CAP_PROP_XI_DEFAULT_CC_MATRIX = 495 , //!< Set default Color Correction Matrix.
CAP_PROP_XI_TRG_SELECTOR = 498 , //!< Selects the type of trigger.
CAP_PROP_XI_ACQ_FRAME_BURST_COUNT = 499 , //!< Sets number of frames acquired by burst. This burst is used only if trigger is set to FrameBurstStart.
CAP_PROP_XI_DEBOUNCE_EN = 507 , //!< Enable/Disable debounce to selected GPI.
CAP_PROP_XI_DEBOUNCE_T0 = 508 , //!< Debounce time (x * 10us).
CAP_PROP_XI_DEBOUNCE_T1 = 509 , //!< Debounce time (x * 10us).
CAP_PROP_XI_DEBOUNCE_POL = 510 , //!< Debounce polarity (pol = 1 t0 - falling edge, t1 - rising edge).
CAP_PROP_XI_LENS_MODE = 511 , //!< Status of lens control interface. This shall be set to XI_ON before any Lens operations.
CAP_PROP_XI_LENS_APERTURE_VALUE = 512 , //!< Current lens aperture value in stops. Examples: 2.8, 4, 5.6, 8, 11.
CAP_PROP_XI_LENS_FOCUS_MOVEMENT_VALUE = 513 , //!< Lens current focus movement value to be used by XI_PRM_LENS_FOCUS_MOVE in motor steps.
CAP_PROP_XI_LENS_FOCUS_MOVE = 514 , //!< Moves lens focus motor by steps set in XI_PRM_LENS_FOCUS_MOVEMENT_VALUE.
CAP_PROP_XI_LENS_FOCUS_DISTANCE = 515 , //!< Lens focus distance in cm.
CAP_PROP_XI_LENS_FOCAL_LENGTH = 516 , //!< Lens focal distance in mm.
CAP_PROP_XI_LENS_FEATURE_SELECTOR = 517 , //!< Selects the current feature which is accessible by XI_PRM_LENS_FEATURE.
CAP_PROP_XI_LENS_FEATURE = 518 , //!< Allows access to lens feature value currently selected by XI_PRM_LENS_FEATURE_SELECTOR.
CAP_PROP_XI_DEVICE_MODEL_ID = 521 , //!< Returns device model id.
CAP_PROP_XI_DEVICE_SN = 522 , //!< Returns device serial number.
CAP_PROP_XI_IMAGE_DATA_FORMAT_RGB32_ALPHA = 529 , //!< The alpha channel of RGB32 output image format.
CAP_PROP_XI_IMAGE_PAYLOAD_SIZE = 530 , //!< Buffer size in bytes sufficient for output image returned by xiGetImage.
CAP_PROP_XI_TRANSPORT_PIXEL_FORMAT = 531 , //!< Current format of pixels on transport layer.
CAP_PROP_XI_SENSOR_CLOCK_FREQ_HZ = 532 , //!< Sensor clock frequency in Hz.
CAP_PROP_XI_SENSOR_CLOCK_FREQ_INDEX = 533 , //!< Sensor clock frequency index. Sensor with selected frequencies have possibility to set the frequency only by this index.
CAP_PROP_XI_SENSOR_OUTPUT_CHANNEL_COUNT = 534 , //!< Number of output channels from sensor used for data transfer.
CAP_PROP_XI_FRAMERATE = 535 , //!< Define framerate in Hz.
CAP_PROP_XI_COUNTER_SELECTOR = 536 , //!< Select counter.
CAP_PROP_XI_COUNTER_VALUE = 537 , //!< Counter status.
CAP_PROP_XI_ACQ_TIMING_MODE = 538 , //!< Type of sensor frames timing.
CAP_PROP_XI_AVAILABLE_BANDWIDTH = 539 , //!< Calculate and returns available interface bandwidth(int Megabits).
CAP_PROP_XI_BUFFER_POLICY = 540 , //!< Data move policy.
CAP_PROP_XI_LUT_EN = 541 , //!< Activates LUT.
CAP_PROP_XI_LUT_INDEX = 542 , //!< Control the index (offset) of the coefficient to access in the LUT.
CAP_PROP_XI_LUT_VALUE = 543 , //!< Value at entry LUTIndex of the LUT.
CAP_PROP_XI_TRG_DELAY = 544 , //!< Specifies the delay in microseconds (us) to apply after the trigger reception before activating it.
CAP_PROP_XI_TS_RST_MODE = 545 , //!< Defines how time stamp reset engine will be armed.
CAP_PROP_XI_TS_RST_SOURCE = 546 , //!< Defines which source will be used for timestamp reset. Writing this parameter will trigger settings of engine (arming).
CAP_PROP_XI_IS_DEVICE_EXIST = 547 , //!< Returns 1 if camera connected and works properly.
CAP_PROP_XI_ACQ_BUFFER_SIZE = 548 , //!< Acquisition buffer size in buffer_size_unit. Default bytes.
CAP_PROP_XI_ACQ_BUFFER_SIZE_UNIT = 549 , //!< Acquisition buffer size unit in bytes. Default 1. E.g. Value 1024 means that buffer_size is in KiBytes.
CAP_PROP_XI_ACQ_TRANSPORT_BUFFER_SIZE = 550 , //!< Acquisition transport buffer size in bytes.
CAP_PROP_XI_BUFFERS_QUEUE_SIZE = 551 , //!< Queue of field/frame buffers.
CAP_PROP_XI_ACQ_TRANSPORT_BUFFER_COMMIT = 552 , //!< Number of buffers to commit to low level.
CAP_PROP_XI_RECENT_FRAME = 553 , //!< GetImage returns most recent frame.
CAP_PROP_XI_DEVICE_RESET = 554 , //!< Resets the camera to default state.
CAP_PROP_XI_COLUMN_FPN_CORRECTION = 555 , //!< Correction of column FPN.
CAP_PROP_XI_ROW_FPN_CORRECTION = 591 , //!< Correction of row FPN.
CAP_PROP_XI_SENSOR_MODE = 558 , //!< Current sensor mode. Allows to select sensor mode by one integer. Setting of this parameter affects: image dimensions and downsampling.
CAP_PROP_XI_HDR = 559 , //!< Enable High Dynamic Range feature.
CAP_PROP_XI_HDR_KNEEPOINT_COUNT = 560 , //!< The number of kneepoints in the PWLR.
CAP_PROP_XI_HDR_T1 = 561 , //!< Position of first kneepoint(in % of XI_PRM_EXPOSURE).
CAP_PROP_XI_HDR_T2 = 562 , //!< Position of second kneepoint (in % of XI_PRM_EXPOSURE).
CAP_PROP_XI_KNEEPOINT1 = 563 , //!< Value of first kneepoint (% of sensor saturation).
CAP_PROP_XI_KNEEPOINT2 = 564 , //!< Value of second kneepoint (% of sensor saturation).
CAP_PROP_XI_IMAGE_BLACK_LEVEL = 565 , //!< Last image black level counts. Can be used for Offline processing to recall it.
CAP_PROP_XI_HW_REVISION = 571 , //!< Returns hardware revision number.
CAP_PROP_XI_DEBUG_LEVEL = 572 , //!< Set debug level.
CAP_PROP_XI_AUTO_BANDWIDTH_CALCULATION = 573 , //!< Automatic bandwidth calculation.
CAP_PROP_XI_FFS_FILE_ID = 594 , //!< File number.
CAP_PROP_XI_FFS_FILE_SIZE = 580 , //!< Size of file.
CAP_PROP_XI_FREE_FFS_SIZE = 581 , //!< Size of free camera FFS.
CAP_PROP_XI_USED_FFS_SIZE = 582 , //!< Size of used camera FFS.
CAP_PROP_XI_FFS_ACCESS_KEY = 583 , //!< Setting of key enables file operations on some cameras.
CAP_PROP_XI_SENSOR_FEATURE_SELECTOR = 585 , //!< Selects the current feature which is accessible by XI_PRM_SENSOR_FEATURE_VALUE.
CAP_PROP_XI_SENSOR_FEATURE_VALUE = 586 , //!< Allows access to sensor feature value currently selected by XI_PRM_SENSOR_FEATURE_SELECTOR.
} ;
//! @} XIMEA
/** @name AVFoundation framework for iOS
OS X Lion will have the same API
@ {
*/
//! Properties of cameras available through AVFOUNDATION backend
enum { CAP_PROP_IOS_DEVICE_FOCUS = 9001 ,
CAP_PROP_IOS_DEVICE_EXPOSURE = 9002 ,
CAP_PROP_IOS_DEVICE_FLASH = 9003 ,
CAP_PROP_IOS_DEVICE_WHITEBALANCE = 9004 ,
CAP_PROP_IOS_DEVICE_TORCH = 9005
} ;
/** @name Smartek Giganetix GigEVisionSDK
@ {
*/
//! Properties of cameras available through Smartek Giganetix Ethernet Vision backend
/* --- Vladimir Litvinenko (litvinenko.vladimir@gmail.com) --- */
enum { CAP_PROP_GIGA_FRAME_OFFSET_X = 10001 ,
CAP_PROP_GIGA_FRAME_OFFSET_Y = 10002 ,
CAP_PROP_GIGA_FRAME_WIDTH_MAX = 10003 ,
CAP_PROP_GIGA_FRAME_HEIGH_MAX = 10004 ,
CAP_PROP_GIGA_FRAME_SENS_WIDTH = 10005 ,
CAP_PROP_GIGA_FRAME_SENS_HEIGH = 10006
} ;
//! @} Smartek
/** @name Intel Perceptual Computing SDK
@ {
*/
enum { CAP_PROP_INTELPERC_PROFILE_COUNT = 11001 ,
CAP_PROP_INTELPERC_PROFILE_IDX = 11002 ,
CAP_PROP_INTELPERC_DEPTH_LOW_CONFIDENCE_VALUE = 11003 ,
CAP_PROP_INTELPERC_DEPTH_SATURATION_VALUE = 11004 ,
CAP_PROP_INTELPERC_DEPTH_CONFIDENCE_THRESHOLD = 11005 ,
CAP_PROP_INTELPERC_DEPTH_FOCAL_LENGTH_HORZ = 11006 ,
CAP_PROP_INTELPERC_DEPTH_FOCAL_LENGTH_VERT = 11007
} ;
//! Intel Perceptual Streams
enum { CAP_INTELPERC_DEPTH_GENERATOR = 1 < < 29 ,
CAP_INTELPERC_IMAGE_GENERATOR = 1 < < 28 ,
CAP_INTELPERC_GENERATORS_MASK = CAP_INTELPERC_DEPTH_GENERATOR + CAP_INTELPERC_IMAGE_GENERATOR
} ;
enum { CAP_INTELPERC_DEPTH_MAP = 0 , //!< Each pixel is a 16-bit integer. The value indicates the distance from an object to the camera's XY plane or the Cartesian depth.
CAP_INTELPERC_UVDEPTH_MAP = 1 , //!< Each pixel contains two 32-bit floating point values in the range of 0-1, representing the mapping of depth coordinates to the color coordinates.
CAP_INTELPERC_IR_MAP = 2 , //!< Each pixel is a 16-bit integer. The value indicates the intensity of the reflected laser beam.
CAP_INTELPERC_IMAGE = 3
} ;
//! @} Intel Perceptual
/** @name gPhoto2 connection
@ {
*/
/** @brief gPhoto2 properties
If ` propertyId ` is less than 0 then work on widget with that __additive inversed__ camera setting ID
Get IDs by using CAP_PROP_GPHOTO2_WIDGET_ENUMERATE .
@ see CvCaptureCAM_GPHOTO2 for more info
*/
enum { CAP_PROP_GPHOTO2_PREVIEW = 17001 , //!< Capture only preview from liveview mode.
CAP_PROP_GPHOTO2_WIDGET_ENUMERATE = 17002 , //!< Readonly, returns (const char *).
CAP_PROP_GPHOTO2_RELOAD_CONFIG = 17003 , //!< Trigger, only by set. Reload camera settings.
CAP_PROP_GPHOTO2_RELOAD_ON_CHANGE = 17004 , //!< Reload all settings on set.
CAP_PROP_GPHOTO2_COLLECT_MSGS = 17005 , //!< Collect messages with details.
CAP_PROP_GPHOTO2_FLUSH_MSGS = 17006 , //!< Readonly, returns (const char *).
CAP_PROP_SPEED = 17007 , //!< Exposure speed. Can be readonly, depends on camera program.
CAP_PROP_APERTURE = 17008 , //!< Aperture. Can be readonly, depends on camera program.
CAP_PROP_EXPOSUREPROGRAM = 17009 , //!< Camera exposure program.
CAP_PROP_VIEWFINDER = 17010 //!< Enter liveview mode.
} ;
//! @} gPhoto2
/** @name Images backend
@ {
*/
/** @brief Images backend properties
*/
enum { CAP_PROP_IMAGES_BASE = 18000 ,
CAP_PROP_IMAGES_LAST = 19000 // excluding
} ;
//! @} Images
//! @} videoio_flags_others
class IVideoCapture ;
/** @brief Class for video capturing from video files, image sequences or cameras.
The class provides C + + API for capturing video from cameras or for reading video files and image sequences .
Here is how the class can be used :
@ include samples / cpp / videocapture_basic . cpp
@ note In @ ref videoio_c " C API " the black - box structure ` CvCapture ` is used instead of % VideoCapture .
@ note
- ( C + + ) A basic sample on using the % VideoCapture interface can be found at
` OPENCV_SOURCE_CODE / samples / cpp / videocapture_starter . cpp `
- ( Python ) A basic sample on using the % VideoCapture interface can be found at
` OPENCV_SOURCE_CODE / samples / python / video . py `
- ( Python ) A multi threaded video processing sample can be found at
` OPENCV_SOURCE_CODE / samples / python / video_threaded . py `
- ( Python ) % VideoCapture sample showcasing some features of the Video4Linux2 backend
` OPENCV_SOURCE_CODE / samples / python / video_v4l2 . py `
*/
class CV_EXPORTS_W VideoCapture
{
public :
/** @brief Default constructor
@ note In @ ref videoio_c " C API " , when you finished working with video , release CvCapture structure with
cvReleaseCapture ( ) , or use Ptr \ < CvCapture \ > that calls cvReleaseCapture ( ) automatically in the
destructor .
*/
CV_WRAP VideoCapture ( ) ;
/** @overload
@ brief Open video file or image file sequence or a capturing device or a IP video stream for video capturing
Same as VideoCapture ( const String & filename , int apiPreference ) but using default Capture API backends
*/
CV_WRAP VideoCapture ( const String & filename ) ;
/** @overload
@ brief Open video file or a capturing device or a IP video stream for video capturing with API Preference
@ param filename it can be :
- name of video file ( eg . ` video . avi ` )
- or image sequence ( eg . ` img_ % 02 d . jpg ` , which will read samples like ` img_00 . jpg , img_01 . jpg , img_02 . jpg , . . . ` )
- or URL of video stream ( eg . ` protocol : //host:port/script_name?script_params|auth`)
- or GStreamer pipeline string in gst - launch tool format in case if GStreamer is used as backend
Note that each video stream or IP camera feed has its own URL scheme . Please refer to the
documentation of source stream to know the right URL .
@ param apiPreference preferred Capture API backends to use . Can be used to enforce a specific reader
implementation if multiple are available : e . g . cv : : CAP_FFMPEG or cv : : CAP_IMAGES or cv : : CAP_DSHOW .
@ sa cv : : VideoCaptureAPIs
*/
CV_WRAP VideoCapture ( const String & filename , int apiPreference ) ;
/** @overload
@ brief Open a camera for video capturing
@ param index camera_id + domain_offset ( CAP_ * ) id of the video capturing device to open . To open default camera using default backend just pass 0.
Use a ` domain_offset ` to enforce a specific reader implementation if multiple are available like cv : : CAP_FFMPEG or cv : : CAP_IMAGES or cv : : CAP_DSHOW .
e . g . to open Camera 1 using the MS Media Foundation API use ` index = 1 + cv : : CAP_MSMF `
@ sa cv : : VideoCaptureAPIs
*/
CV_WRAP VideoCapture ( int index ) ;
/** @overload
@ brief Opens a camera for video capturing
@ param index id of the video capturing device to open . To open default camera using default backend just pass 0.
( to backward compatibility usage of camera_id + domain_offset ( CAP_ * ) is valid when apiPreference is CAP_ANY )
@ param apiPreference preferred Capture API backends to use . Can be used to enforce a specific reader
implementation if multiple are available : e . g . cv : : CAP_DSHOW or cv : : CAP_MSMF or cv : : CAP_V4L2 .
@ sa cv : : VideoCaptureAPIs
*/
CV_WRAP VideoCapture ( int index , int apiPreference ) ;
/** @brief Default destructor
The method first calls VideoCapture : : release to close the already opened file or camera .
*/
virtual ~ VideoCapture ( ) ;
/** @brief Open video file or a capturing device or a IP video stream for video capturing
@ overload
Parameters are same as the constructor VideoCapture ( const String & filename )
@ return ` true ` if the file has been successfully opened
The method first calls VideoCapture : : release to close the already opened file or camera .
*/
CV_WRAP virtual bool open ( const String & filename ) ;
/** @brief Open a camera for video capturing
@ overload
Parameters are same as the constructor VideoCapture ( int index )
@ return ` true ` if the camera has been successfully opened .
The method first calls VideoCapture : : release to close the already opened file or camera .
*/
CV_WRAP virtual bool open ( int index ) ;
/** @brief Open a camera for video capturing
@ overload
Parameters are similar as the constructor VideoCapture ( int index ) , except it takes an additional argument apiPreference .
Definitely , is same as open ( int index ) where ` index = cameraNum + apiPreference `
@ return ` true ` if the camera has been successfully opened .
*/
CV_WRAP bool open ( int cameraNum , int apiPreference ) ;
/** @brief Returns true if video capturing has been initialized already.
If the previous call to VideoCapture constructor or VideoCapture : : open ( ) succeeded , the method returns
true .
*/
CV_WRAP virtual bool isOpened ( ) const ;
/** @brief Closes video file or capturing device.
The method is automatically called by subsequent VideoCapture : : open and by VideoCapture
destructor .
The C function also deallocates memory and clears \ * capture pointer .
*/
CV_WRAP virtual void release ( ) ;
/** @brief Grabs the next frame from video file or capturing device.
@ return ` true ` ( non - zero ) in the case of success .
The method / function grabs the next frame from video file or camera and returns true ( non - zero ) in
the case of success .
The primary use of the function is in multi - camera environments , especially when the cameras do not
have hardware synchronization . That is , you call VideoCapture : : grab ( ) for each camera and after that
call the slower method VideoCapture : : retrieve ( ) to decode and get frame from each camera . This way
the overhead on demosaicing or motion jpeg decompression etc . is eliminated and the retrieved frames
from different cameras will be closer in time .
Also , when a connected camera is multi - head ( for example , a stereo camera or a Kinect device ) , the
correct way of retrieving data from it is to call VideoCapture : : grab ( ) first and then call
VideoCapture : : retrieve ( ) one or more times with different values of the channel parameter .
@ ref tutorial_kinect_openni
*/
CV_WRAP virtual bool grab ( ) ;
/** @brief Decodes and returns the grabbed video frame.
@ param [ out ] image the video frame is returned here . If no frames has been grabbed the image will be empty .
@ param flag it could be a frame index or a driver specific flag
@ return ` false ` if no frames has been grabbed
The method decodes and returns the just grabbed frame . If no frames has been grabbed
( camera has been disconnected , or there are no more frames in video file ) , the method returns false
and the function returns an empty image ( with % cv : : Mat , test it with Mat : : empty ( ) ) .
@ sa read ( )
@ note In @ ref videoio_c " C API " , functions cvRetrieveFrame ( ) and cv . RetrieveFrame ( ) return image stored inside the video
capturing structure . It is not allowed to modify or release the image ! You can copy the frame using
cvCloneImage and then do whatever you want with the copy .
*/
CV_WRAP virtual bool retrieve ( OutputArray image , int flag = 0 ) ;
/** @brief Stream operator to read the next video frame.
@ sa read ( )
*/
virtual VideoCapture & operator > > ( CV_OUT Mat & image ) ;
/** @overload
@ sa read ( )
*/
virtual VideoCapture & operator > > ( CV_OUT UMat & image ) ;
/** @brief Grabs, decodes and returns the next video frame.
@ param [ out ] image the video frame is returned here . If no frames has been grabbed the image will be empty .
@ return ` false ` if no frames has been grabbed
The method / function combines VideoCapture : : grab ( ) and VideoCapture : : retrieve ( ) in one call . This is the
most convenient method for reading video files or capturing data from decode and returns the just
grabbed frame . If no frames has been grabbed ( camera has been disconnected , or there are no more
frames in video file ) , the method returns false and the function returns empty image ( with % cv : : Mat , test it with Mat : : empty ( ) ) .
@ note In @ ref videoio_c " C API " , functions cvRetrieveFrame ( ) and cv . RetrieveFrame ( ) return image stored inside the video
capturing structure . It is not allowed to modify or release the image ! You can copy the frame using
cvCloneImage and then do whatever you want with the copy .
*/
CV_WRAP virtual bool read ( OutputArray image ) ;
/** @brief Sets a property in the VideoCapture.
@ param propId Property identifier from cv : : VideoCaptureProperties ( eg . cv : : CAP_PROP_POS_MSEC , cv : : CAP_PROP_POS_FRAMES , . . . )
or one from @ ref videoio_flags_others
@ param value Value of the property .
@ return ` true ` if the property is supported by backend used by the VideoCapture instance .
@ note Even if it returns ` true ` this doesn ' t ensure that the property
value has been accepted by the capture device . See note in VideoCapture : : get ( )
*/
CV_WRAP virtual bool set ( int propId , double value ) ;
/** @brief Returns the specified VideoCapture property
@ param propId Property identifier from cv : : VideoCaptureProperties ( eg . cv : : CAP_PROP_POS_MSEC , cv : : CAP_PROP_POS_FRAMES , . . . )
or one from @ ref videoio_flags_others
@ return Value for the specified property . Value 0 is returned when querying a property that is
not supported by the backend used by the VideoCapture instance .
@ note Reading / writing properties involves many layers . Some unexpected result might happens
along this chain .
@ code { . txt }
VideoCapture - > API Backend - > Operating System - > Device Driver - > Device Hardware
@ endcode
The returned value might be different from what really used by the device or it could be encoded
using device dependent rules ( eg . steps or percentage ) . Effective behaviour depends from device
driver and API Backend
*/
CV_WRAP virtual double get ( int propId ) const ;
/** @brief Open video file or a capturing device or a IP video stream for video capturing with API Preference
@ overload
Parameters are same as the constructor VideoCapture ( const String & filename , int apiPreference )
@ return ` true ` if the file has been successfully opened
The method first calls VideoCapture : : release to close the already opened file or camera .
*/
CV_WRAP virtual bool open ( const String & filename , int apiPreference ) ;
/** @brief Returns used backend API name
@ note Stream should be opened .
*/
CV_WRAP String getBackendName ( ) const ;
protected :
Ptr < CvCapture > cap ;
Ptr < IVideoCapture > icap ;
} ;
class IVideoWriter ;
/** @example samples/cpp/tutorial_code/videoio/video-write/video-write.cpp
Check @ ref tutorial_video_write " the corresponding tutorial " for more details
*/
/** @example samples/cpp/videowriter_basic.cpp
An example using VideoCapture and VideoWriter class
*/
/** @brief Video writer class.
The class provides C + + API for writing video files or image sequences .
*/
class CV_EXPORTS_W VideoWriter
{
public :
/** @brief Default constructors
The constructors / functions initialize video writers .
- On Linux FFMPEG is used to write videos ;
- On Windows FFMPEG or VFW is used ;
- On MacOSX QTKit is used .
*/
CV_WRAP VideoWriter ( ) ;
/** @overload
@ param filename Name of the output video file .
@ param fourcc 4 - character code of codec used to compress the frames . For example ,
VideoWriter : : fourcc ( ' P ' , ' I ' , ' M ' , ' 1 ' ) is a MPEG - 1 codec , VideoWriter : : fourcc ( ' M ' , ' J ' , ' P ' , ' G ' ) is a
motion - jpeg codec etc . List of codes can be obtained at [ Video Codecs by
FOURCC ] ( http : //www.fourcc.org/codecs.php) page. FFMPEG backend with MP4 container natively uses
other values as fourcc code : see [ ObjectType ] ( http : //mp4ra.org/#/codecs),
so you may receive a warning message from OpenCV about fourcc code conversion .
@ param fps Framerate of the created video stream .
@ param frameSize Size of the video frames .
@ param isColor If it is not zero , the encoder will expect and encode color frames , otherwise it
will work with grayscale frames ( the flag is currently supported on Windows only ) .
@ b Tips :
- With some backends ` fourcc = - 1 ` pops up the codec selection dialog from the system .
- To save image sequence use a proper filename ( eg . ` img_ % 02 d . jpg ` ) and ` fourcc = 0 `
OR ` fps = 0 ` . Use uncompressed image format ( eg . ` img_ % 02 d . BMP ` ) to save raw frames .
- Most codecs are lossy . If you want lossless video file you need to use a lossless codecs
( eg . FFMPEG FFV1 , Huffman HFYU , Lagarith LAGS , etc . . . )
- If FFMPEG is enabled , using ` codec = 0 ; fps = 0 ; ` you can create an uncompressed ( raw ) video file .
*/
CV_WRAP VideoWriter ( const String & filename , int fourcc , double fps ,
Size frameSize , bool isColor = true ) ;
/** @overload
The ` apiPreference ` parameter allows to specify API backends to use . Can be used to enforce a specific reader implementation
if multiple are available : e . g . cv : : CAP_FFMPEG or cv : : CAP_GSTREAMER .
*/
CV_WRAP VideoWriter ( const String & filename , int apiPreference , int fourcc , double fps ,
Size frameSize , bool isColor = true ) ;
/** @brief Default destructor
The method first calls VideoWriter : : release to close the already opened file .
*/
virtual ~ VideoWriter ( ) ;
/** @brief Initializes or reinitializes video writer.
The method opens video writer . Parameters are the same as in the constructor
VideoWriter : : VideoWriter .
@ return ` true ` if video writer has been successfully initialized
The method first calls VideoWriter : : release to close the already opened file .
*/
CV_WRAP virtual bool open ( const String & filename , int fourcc , double fps ,
Size frameSize , bool isColor = true ) ;
/** @overload
*/
CV_WRAP bool open ( const String & filename , int apiPreference , int fourcc , double fps ,
Size frameSize , bool isColor = true ) ;
/** @brief Returns true if video writer has been successfully initialized.
*/
CV_WRAP virtual bool isOpened ( ) const ;
/** @brief Closes the video writer.
The method is automatically called by subsequent VideoWriter : : open and by the VideoWriter
destructor .
*/
CV_WRAP virtual void release ( ) ;
/** @brief Stream operator to write the next video frame.
@ sa write
*/
virtual VideoWriter & operator < < ( const Mat & image ) ;
/** @brief Writes the next video frame
@ param image The written frame . In general , color images are expected in BGR format .
The function / method writes the specified image to video file . It must have the same size as has
been specified when opening the video writer .
*/
CV_WRAP virtual void write ( const Mat & image ) ;
/** @brief Sets a property in the VideoWriter.
@ param propId Property identifier from cv : : VideoWriterProperties ( eg . cv : : VIDEOWRITER_PROP_QUALITY )
or one of @ ref videoio_flags_others
@ param value Value of the property .
@ return ` true ` if the property is supported by the backend used by the VideoWriter instance .
*/
CV_WRAP virtual bool set ( int propId , double value ) ;
/** @brief Returns the specified VideoWriter property
@ param propId Property identifier from cv : : VideoWriterProperties ( eg . cv : : VIDEOWRITER_PROP_QUALITY )
or one of @ ref videoio_flags_others
@ return Value for the specified property . Value 0 is returned when querying a property that is
not supported by the backend used by the VideoWriter instance .
*/
CV_WRAP virtual double get ( int propId ) const ;
/** @brief Concatenates 4 chars to a fourcc code
@ return a fourcc code
This static method constructs the fourcc code of the codec to be used in the constructor
VideoWriter : : VideoWriter or VideoWriter : : open .
*/
CV_WRAP static int fourcc ( char c1 , char c2 , char c3 , char c4 ) ;
/** @brief Returns used backend API name
@ note Stream should be opened .
*/
CV_WRAP String getBackendName ( ) const ;
protected :
Ptr < CvVideoWriter > writer ;
Ptr < IVideoWriter > iwriter ;
static Ptr < IVideoWriter > create ( const String & filename , int fourcc , double fps ,
Size frameSize , bool isColor = true ) ;
} ;
template < > CV_EXPORTS void DefaultDeleter < CvCapture > : : operator ( ) ( CvCapture * obj ) const ;
template < > CV_EXPORTS void DefaultDeleter < CvVideoWriter > : : operator ( ) ( CvVideoWriter * obj ) const ;
//! @} videoio
} // cv
# endif //OPENCV_VIDEOIO_HPP
