OpenCV  5.0.0alpha
Open Source Computer Vision
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Enumerations
Flags for video I/O
Video I/O

Detailed Description

Enumerations

enum  cv::VideoCaptureAPIs {
  cv::CAP_ANY = 0 ,
  cv::CAP_V4L = 200 ,
  cv::CAP_V4L2 = CAP_V4L ,
  cv::CAP_FIREWIRE = 300 ,
  cv::CAP_FIREWARE = CAP_FIREWIRE ,
  cv::CAP_IEEE1394 = CAP_FIREWIRE ,
  cv::CAP_DC1394 = CAP_FIREWIRE ,
  cv::CAP_CMU1394 = CAP_FIREWIRE ,
  cv::CAP_DSHOW = 700 ,
  cv::CAP_PVAPI = 800 ,
  cv::CAP_ANDROID = 1000 ,
  cv::CAP_XIAPI = 1100 ,
  cv::CAP_AVFOUNDATION = 1200 ,
  cv::CAP_MSMF = 1400 ,
  cv::CAP_WINRT = 1410 ,
  cv::CAP_INTELPERC = 1500 ,
  cv::CAP_REALSENSE = 1500 ,
  cv::CAP_OPENNI2 = 1600 ,
  cv::CAP_OPENNI2_ASUS = 1610 ,
  cv::CAP_OPENNI2_ASTRA = 1620 ,
  cv::CAP_GPHOTO2 = 1700 ,
  cv::CAP_GSTREAMER = 1800 ,
  cv::CAP_FFMPEG = 1900 ,
  cv::CAP_IMAGES = 2000 ,
  cv::CAP_ARAVIS = 2100 ,
  cv::CAP_OPENCV_MJPEG = 2200 ,
  cv::CAP_INTEL_MFX = 2300 ,
  cv::CAP_XINE = 2400 ,
  cv::CAP_UEYE = 2500 ,
  cv::CAP_OBSENSOR = 2600
}
 cv::VideoCapture API backends identifier. More...
 
enum  cv::VideoCaptureProperties {
  cv::CAP_PROP_POS_MSEC =0 ,
  cv::CAP_PROP_POS_FRAMES =1 ,
  cv::CAP_PROP_POS_AVI_RATIO =2 ,
  cv::CAP_PROP_FRAME_WIDTH =3 ,
  cv::CAP_PROP_FRAME_HEIGHT =4 ,
  cv::CAP_PROP_FPS =5 ,
  cv::CAP_PROP_FOURCC =6 ,
  cv::CAP_PROP_FRAME_COUNT =7 ,
  cv::CAP_PROP_FORMAT =8 ,
  cv::CAP_PROP_MODE =9 ,
  cv::CAP_PROP_BRIGHTNESS =10 ,
  cv::CAP_PROP_CONTRAST =11 ,
  cv::CAP_PROP_SATURATION =12 ,
  cv::CAP_PROP_HUE =13 ,
  cv::CAP_PROP_GAIN =14 ,
  cv::CAP_PROP_EXPOSURE =15 ,
  cv::CAP_PROP_CONVERT_RGB =16 ,
  cv::CAP_PROP_WHITE_BALANCE_BLUE_U =17 ,
  cv::CAP_PROP_RECTIFICATION =18 ,
  cv::CAP_PROP_MONOCHROME =19 ,
  cv::CAP_PROP_SHARPNESS =20 ,
  cv::CAP_PROP_AUTO_EXPOSURE =21 ,
  cv::CAP_PROP_GAMMA =22 ,
  cv::CAP_PROP_TEMPERATURE =23 ,
  cv::CAP_PROP_TRIGGER =24 ,
  cv::CAP_PROP_TRIGGER_DELAY =25 ,
  cv::CAP_PROP_WHITE_BALANCE_RED_V =26 ,
  cv::CAP_PROP_ZOOM =27 ,
  cv::CAP_PROP_FOCUS =28 ,
  cv::CAP_PROP_GUID =29 ,
  cv::CAP_PROP_ISO_SPEED =30 ,
  cv::CAP_PROP_BACKLIGHT =32 ,
  cv::CAP_PROP_PAN =33 ,
  cv::CAP_PROP_TILT =34 ,
  cv::CAP_PROP_ROLL =35 ,
  cv::CAP_PROP_IRIS =36 ,
  cv::CAP_PROP_SETTINGS =37 ,
  cv::CAP_PROP_BUFFERSIZE =38 ,
  cv::CAP_PROP_AUTOFOCUS =39 ,
  cv::CAP_PROP_SAR_NUM =40 ,
  cv::CAP_PROP_SAR_DEN =41 ,
  cv::CAP_PROP_BACKEND =42 ,
  cv::CAP_PROP_CHANNEL =43 ,
  cv::CAP_PROP_AUTO_WB =44 ,
  cv::CAP_PROP_WB_TEMPERATURE =45 ,
  cv::CAP_PROP_CODEC_PIXEL_FORMAT =46 ,
  cv::CAP_PROP_BITRATE =47 ,
  cv::CAP_PROP_ORIENTATION_META =48 ,
  cv::CAP_PROP_ORIENTATION_AUTO =49 ,
  cv::CAP_PROP_HW_ACCELERATION =50 ,
  cv::CAP_PROP_HW_DEVICE =51 ,
  cv::CAP_PROP_HW_ACCELERATION_USE_OPENCL =52 ,
  cv::CAP_PROP_OPEN_TIMEOUT_MSEC =53 ,
  cv::CAP_PROP_READ_TIMEOUT_MSEC =54 ,
  cv::CAP_PROP_STREAM_OPEN_TIME_USEC =55 ,
  cv::CAP_PROP_VIDEO_TOTAL_CHANNELS = 56 ,
  cv::CAP_PROP_VIDEO_STREAM = 57 ,
  cv::CAP_PROP_AUDIO_STREAM = 58 ,
  cv::CAP_PROP_AUDIO_POS = 59 ,
  cv::CAP_PROP_AUDIO_SHIFT_NSEC = 60 ,
  cv::CAP_PROP_AUDIO_DATA_DEPTH = 61 ,
  cv::CAP_PROP_AUDIO_SAMPLES_PER_SECOND = 62 ,
  cv::CAP_PROP_AUDIO_BASE_INDEX = 63 ,
  cv::CAP_PROP_AUDIO_TOTAL_CHANNELS = 64 ,
  cv::CAP_PROP_AUDIO_TOTAL_STREAMS = 65 ,
  cv::CAP_PROP_AUDIO_SYNCHRONIZE = 66 ,
  cv::CAP_PROP_LRF_HAS_KEY_FRAME = 67 ,
  cv::CAP_PROP_CODEC_EXTRADATA_INDEX = 68 ,
  cv::CAP_PROP_FRAME_TYPE = 69 ,
  cv::CAP_PROP_N_THREADS = 70 ,
  cv::CAP_PROP_PTS = 71 ,
  cv::CAP_PROP_DTS_DELAY = 72
}
 cv::VideoCapture generic properties identifier. More...
 
enum  cv::VideoWriterProperties {
  cv::VIDEOWRITER_PROP_QUALITY = 1 ,
  cv::VIDEOWRITER_PROP_FRAMEBYTES = 2 ,
  cv::VIDEOWRITER_PROP_NSTRIPES = 3 ,
  cv::VIDEOWRITER_PROP_IS_COLOR = 4 ,
  cv::VIDEOWRITER_PROP_DEPTH = 5 ,
  cv::VIDEOWRITER_PROP_HW_ACCELERATION = 6 ,
  cv::VIDEOWRITER_PROP_HW_DEVICE = 7 ,
  cv::VIDEOWRITER_PROP_HW_ACCELERATION_USE_OPENCL = 8 ,
  cv::VIDEOWRITER_PROP_RAW_VIDEO = 9 ,
  cv::VIDEOWRITER_PROP_KEY_INTERVAL = 10 ,
  cv::VIDEOWRITER_PROP_KEY_FLAG = 11 ,
  cv::VIDEOWRITER_PROP_PTS = 12 ,
  cv::VIDEOWRITER_PROP_DTS_DELAY = 13
}
 cv::VideoWriter generic properties identifier. More...
 

Enumeration Type Documentation

◆ VideoCaptureAPIs

enum cv::VideoCaptureAPIs

#include <opencv2/videoio.hpp>

cv::VideoCapture API backends identifier.

Select preferred API for a capture object. To be used in the VideoCapture::VideoCapture() constructor or VideoCapture::open()

Note
Enumerator
CAP_ANY 
Python: cv.CAP_ANY

Auto detect == 0.

CAP_V4L 
Python: cv.CAP_V4L

V4L/V4L2 capturing support.

CAP_V4L2 
Python: cv.CAP_V4L2

Same as CAP_V4L.

CAP_FIREWIRE 
Python: cv.CAP_FIREWIRE

IEEE 1394 drivers.

CAP_FIREWARE 
Python: cv.CAP_FIREWARE

Same value as CAP_FIREWIRE.

CAP_IEEE1394 
Python: cv.CAP_IEEE1394

Same value as CAP_FIREWIRE.

CAP_DC1394 
Python: cv.CAP_DC1394

Same value as CAP_FIREWIRE.

CAP_CMU1394 
Python: cv.CAP_CMU1394

Same value as CAP_FIREWIRE.

CAP_DSHOW 
Python: cv.CAP_DSHOW

DirectShow (via videoInput)

CAP_PVAPI 
Python: cv.CAP_PVAPI

PvAPI, Prosilica GigE SDK.

CAP_ANDROID 
Python: cv.CAP_ANDROID

MediaNDK (API Level 21+) and NDK Camera (API level 24+) for Android.

CAP_XIAPI 
Python: cv.CAP_XIAPI

XIMEA Camera API.

CAP_AVFOUNDATION 
Python: cv.CAP_AVFOUNDATION

AVFoundation framework for iOS (OS X Lion will have the same API)

CAP_MSMF 
Python: cv.CAP_MSMF

Microsoft Media Foundation (via videoInput). See platform specific notes above.

CAP_WINRT 
Python: cv.CAP_WINRT

Microsoft Windows Runtime using Media Foundation.

CAP_INTELPERC 
Python: cv.CAP_INTELPERC

RealSense (former Intel Perceptual Computing SDK)

CAP_REALSENSE 
Python: cv.CAP_REALSENSE

Synonym for CAP_INTELPERC.

CAP_OPENNI2 
Python: cv.CAP_OPENNI2

OpenNI2 (for Kinect)

CAP_OPENNI2_ASUS 
Python: cv.CAP_OPENNI2_ASUS

OpenNI2 (for Asus Xtion and Occipital Structure sensors)

CAP_OPENNI2_ASTRA 
Python: cv.CAP_OPENNI2_ASTRA

OpenNI2 (for Orbbec Astra)

CAP_GPHOTO2 
Python: cv.CAP_GPHOTO2

gPhoto2 connection

CAP_GSTREAMER 
Python: cv.CAP_GSTREAMER

GStreamer.

CAP_FFMPEG 
Python: cv.CAP_FFMPEG

Open and record video file or stream using the FFMPEG library.

CAP_IMAGES 
Python: cv.CAP_IMAGES

OpenCV Image Sequence (e.g. img_%02d.jpg)

CAP_ARAVIS 
Python: cv.CAP_ARAVIS

Aravis SDK.

CAP_OPENCV_MJPEG 
Python: cv.CAP_OPENCV_MJPEG

Built-in OpenCV MotionJPEG codec.

CAP_INTEL_MFX 
Python: cv.CAP_INTEL_MFX

Intel MediaSDK.

CAP_XINE 
Python: cv.CAP_XINE

XINE engine (Linux)

CAP_UEYE 
Python: cv.CAP_UEYE

uEye Camera API

CAP_OBSENSOR 
Python: cv.CAP_OBSENSOR

For Orbbec 3D-Sensor device/module (Astra+, Femto, Astra2, Gemini2, Gemini2L, Gemini2XL, Femto Mega) attention: Astra2 cameras currently only support Windows and Linux kernel versions no higher than 4.15, and higher versions of Linux kernel may have exceptions.

◆ VideoCaptureProperties

enum cv::VideoCaptureProperties

#include <opencv2/videoio.hpp>

cv::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.

See also
Additional flags for video I/O API backends, VideoCapture::get(), VideoCapture::set()
Enumerator
CAP_PROP_POS_MSEC 
Python: cv.CAP_PROP_POS_MSEC

Current position of the video file in milliseconds.

CAP_PROP_POS_FRAMES 
Python: cv.CAP_PROP_POS_FRAMES

0-based index of the frame to be decoded/captured next. When the index i is set in RAW mode (CAP_PROP_FORMAT == -1) this will seek to the key frame k, where k <= i.

CAP_PROP_POS_AVI_RATIO 
Python: cv.CAP_PROP_POS_AVI_RATIO

Relative position of the video file: 0=start of the film, 1=end of the film.

CAP_PROP_FRAME_WIDTH 
Python: cv.CAP_PROP_FRAME_WIDTH

Width of the frames in the video stream.

CAP_PROP_FRAME_HEIGHT 
Python: cv.CAP_PROP_FRAME_HEIGHT

Height of the frames in the video stream.

CAP_PROP_FPS 
Python: cv.CAP_PROP_FPS

Frame rate.

CAP_PROP_FOURCC 
Python: cv.CAP_PROP_FOURCC

4-character code of codec. see VideoWriter::fourcc .

CAP_PROP_FRAME_COUNT 
Python: cv.CAP_PROP_FRAME_COUNT

Number of frames in the video file.

CAP_PROP_FORMAT 
Python: cv.CAP_PROP_FORMAT

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 
Python: cv.CAP_PROP_MODE

Backend-specific value indicating the current capture mode.

CAP_PROP_BRIGHTNESS 
Python: cv.CAP_PROP_BRIGHTNESS

Brightness of the image (only for those cameras that support).

CAP_PROP_CONTRAST 
Python: cv.CAP_PROP_CONTRAST

Contrast of the image (only for cameras).

CAP_PROP_SATURATION 
Python: cv.CAP_PROP_SATURATION

Saturation of the image (only for cameras).

CAP_PROP_HUE 
Python: cv.CAP_PROP_HUE

Hue of the image (only for cameras).

CAP_PROP_GAIN 
Python: cv.CAP_PROP_GAIN

Gain of the image (only for those cameras that support).

CAP_PROP_EXPOSURE 
Python: cv.CAP_PROP_EXPOSURE

Exposure (only for those cameras that support).

CAP_PROP_CONVERT_RGB 
Python: cv.CAP_PROP_CONVERT_RGB

Boolean flags indicating whether images should be converted to RGB.
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 
Python: cv.CAP_PROP_WHITE_BALANCE_BLUE_U

Currently unsupported.

CAP_PROP_RECTIFICATION 
Python: cv.CAP_PROP_RECTIFICATION

Rectification flag for stereo cameras (note: only supported by DC1394 v 2.x backend currently).

CAP_PROP_MONOCHROME 
Python: cv.CAP_PROP_MONOCHROME
CAP_PROP_SHARPNESS 
Python: cv.CAP_PROP_SHARPNESS
CAP_PROP_AUTO_EXPOSURE 
Python: cv.CAP_PROP_AUTO_EXPOSURE

DC1394: exposure control done by camera, user can adjust reference level using this feature.

CAP_PROP_GAMMA 
Python: cv.CAP_PROP_GAMMA
CAP_PROP_TEMPERATURE 
Python: cv.CAP_PROP_TEMPERATURE
CAP_PROP_TRIGGER 
Python: cv.CAP_PROP_TRIGGER
CAP_PROP_TRIGGER_DELAY 
Python: cv.CAP_PROP_TRIGGER_DELAY
CAP_PROP_WHITE_BALANCE_RED_V 
Python: cv.CAP_PROP_WHITE_BALANCE_RED_V
CAP_PROP_ZOOM 
Python: cv.CAP_PROP_ZOOM
CAP_PROP_FOCUS 
Python: cv.CAP_PROP_FOCUS
CAP_PROP_GUID 
Python: cv.CAP_PROP_GUID
CAP_PROP_ISO_SPEED 
Python: cv.CAP_PROP_ISO_SPEED
CAP_PROP_BACKLIGHT 
Python: cv.CAP_PROP_BACKLIGHT
CAP_PROP_PAN 
Python: cv.CAP_PROP_PAN
CAP_PROP_TILT 
Python: cv.CAP_PROP_TILT
CAP_PROP_ROLL 
Python: cv.CAP_PROP_ROLL
CAP_PROP_IRIS 
Python: cv.CAP_PROP_IRIS
CAP_PROP_SETTINGS 
Python: cv.CAP_PROP_SETTINGS

Pop up video/camera filter dialog (note: only supported by DSHOW backend currently. The property value is ignored)

CAP_PROP_BUFFERSIZE 
Python: cv.CAP_PROP_BUFFERSIZE
CAP_PROP_AUTOFOCUS 
Python: cv.CAP_PROP_AUTOFOCUS
CAP_PROP_SAR_NUM 
Python: cv.CAP_PROP_SAR_NUM

Sample aspect ratio: num/den (num)

CAP_PROP_SAR_DEN 
Python: cv.CAP_PROP_SAR_DEN

Sample aspect ratio: num/den (den)

CAP_PROP_BACKEND 
Python: cv.CAP_PROP_BACKEND

Current backend (enum VideoCaptureAPIs). Read-only property.

CAP_PROP_CHANNEL 
Python: cv.CAP_PROP_CHANNEL

Video input or Channel Number (only for those cameras that support)

CAP_PROP_AUTO_WB 
Python: cv.CAP_PROP_AUTO_WB

enable/ disable auto white-balance

CAP_PROP_WB_TEMPERATURE 
Python: cv.CAP_PROP_WB_TEMPERATURE

white-balance color temperature

CAP_PROP_CODEC_PIXEL_FORMAT 
Python: cv.CAP_PROP_CODEC_PIXEL_FORMAT

(read-only) codec's pixel format. 4-character code - see VideoWriter::fourcc . Subset of AV_PIX_FMT_* or -1 if unknown

CAP_PROP_BITRATE 
Python: cv.CAP_PROP_BITRATE

(read-only) Video bitrate in kbits/s

CAP_PROP_ORIENTATION_META 
Python: cv.CAP_PROP_ORIENTATION_META

(read-only) Frame rotation defined by stream meta (applicable for FFmpeg and AVFoundation back-ends only)

CAP_PROP_ORIENTATION_AUTO 
Python: cv.CAP_PROP_ORIENTATION_AUTO

if true - rotates output frames of CvCapture considering video file's metadata (applicable for FFmpeg and AVFoundation back-ends only) (https://github.com/opencv/opencv/issues/15499)

CAP_PROP_HW_ACCELERATION 
Python: cv.CAP_PROP_HW_ACCELERATION

(open-only) Hardware acceleration type (see VideoAccelerationType). Setting supported only via params parameter in cv::VideoCapture constructor / .open() method. Default value is backend-specific.

CAP_PROP_HW_DEVICE 
Python: cv.CAP_PROP_HW_DEVICE

(open-only) Hardware device index (select GPU if multiple available). Device enumeration is acceleration type specific.

CAP_PROP_HW_ACCELERATION_USE_OPENCL 
Python: cv.CAP_PROP_HW_ACCELERATION_USE_OPENCL

(open-only) If non-zero, create new OpenCL context and bind it to current thread. The OpenCL context created with Video Acceleration context attached it (if not attached yet) for optimized GPU data copy between HW accelerated decoder and cv::UMat.

CAP_PROP_OPEN_TIMEOUT_MSEC 
Python: cv.CAP_PROP_OPEN_TIMEOUT_MSEC

(open-only) timeout in milliseconds for opening a video capture (applicable for FFmpeg and GStreamer back-ends only)

CAP_PROP_READ_TIMEOUT_MSEC 
Python: cv.CAP_PROP_READ_TIMEOUT_MSEC

(open-only) timeout in milliseconds for reading from a video capture (applicable for FFmpeg and GStreamer back-ends only)

CAP_PROP_STREAM_OPEN_TIME_USEC 
Python: cv.CAP_PROP_STREAM_OPEN_TIME_USEC

(read-only) time in microseconds since Jan 1 1970 when stream was opened. Applicable for FFmpeg backend only. Useful for RTSP and other live streams

CAP_PROP_VIDEO_TOTAL_CHANNELS 
Python: cv.CAP_PROP_VIDEO_TOTAL_CHANNELS

(read-only) Number of video channels

CAP_PROP_VIDEO_STREAM 
Python: cv.CAP_PROP_VIDEO_STREAM

(open-only) Specify video stream, 0-based index. Use -1 to disable video stream from file or IP cameras. Default value is 0.

CAP_PROP_AUDIO_STREAM 
Python: cv.CAP_PROP_AUDIO_STREAM

(open-only) Specify stream in multi-language media files, -1 - disable audio processing or microphone. Default value is -1.

CAP_PROP_AUDIO_POS 
Python: cv.CAP_PROP_AUDIO_POS

(read-only) Audio position is measured in samples. Accurate audio sample timestamp of previous grabbed fragment. See CAP_PROP_AUDIO_SAMPLES_PER_SECOND and CAP_PROP_AUDIO_SHIFT_NSEC.

CAP_PROP_AUDIO_SHIFT_NSEC 
Python: cv.CAP_PROP_AUDIO_SHIFT_NSEC

(read only) Contains the time difference between the start of the audio stream and the video stream in nanoseconds. Positive value means that audio is started after the first video frame. Negative value means that audio is started before the first video frame.

CAP_PROP_AUDIO_DATA_DEPTH 
Python: cv.CAP_PROP_AUDIO_DATA_DEPTH

(open, read) Alternative definition to bits-per-sample, but with clear handling of 32F / 32S

CAP_PROP_AUDIO_SAMPLES_PER_SECOND 
Python: cv.CAP_PROP_AUDIO_SAMPLES_PER_SECOND

(open, read) determined from file/codec input. If not specified, then selected audio sample rate is 44100

CAP_PROP_AUDIO_BASE_INDEX 
Python: cv.CAP_PROP_AUDIO_BASE_INDEX

(read-only) Index of the first audio channel for .retrieve() calls. That audio channel number continues enumeration after video channels.

CAP_PROP_AUDIO_TOTAL_CHANNELS 
Python: cv.CAP_PROP_AUDIO_TOTAL_CHANNELS

(read-only) Number of audio channels in the selected audio stream (mono, stereo, etc)

CAP_PROP_AUDIO_TOTAL_STREAMS 
Python: cv.CAP_PROP_AUDIO_TOTAL_STREAMS

(read-only) Number of audio streams.

CAP_PROP_AUDIO_SYNCHRONIZE 
Python: cv.CAP_PROP_AUDIO_SYNCHRONIZE

(open, read) Enables audio synchronization.

CAP_PROP_LRF_HAS_KEY_FRAME 
Python: cv.CAP_PROP_LRF_HAS_KEY_FRAME

FFmpeg back-end only - Indicates whether the Last Raw Frame (LRF), output from VideoCapture::read() when VideoCapture is initialized with VideoCapture::open(CAP_FFMPEG, {CAP_PROP_FORMAT, -1}) or VideoCapture::set(CAP_PROP_FORMAT,-1) is called before the first call to VideoCapture::read(), contains encoded data for a key frame.

CAP_PROP_CODEC_EXTRADATA_INDEX 
Python: cv.CAP_PROP_CODEC_EXTRADATA_INDEX

Positive index indicates that returning extra data is supported by the video back end. This can be retrieved as cap.retrieve(data, <returned index>). E.g. When reading from a h264 encoded RTSP stream, the FFmpeg backend could return the SPS and/or PPS if available (if sent in reply to a DESCRIBE request), from calls to cap.retrieve(data, <returned index>).

CAP_PROP_FRAME_TYPE 
Python: cv.CAP_PROP_FRAME_TYPE

(read-only) FFmpeg back-end only - Frame type ascii code (73 = 'I', 80 = 'P', 66 = 'B' or 63 = '?' if unknown) of the most recently read frame.

CAP_PROP_N_THREADS 
Python: cv.CAP_PROP_N_THREADS

(open-only) Set the maximum number of threads to use. Use 0 to use as many threads as CPU cores (applicable for FFmpeg back-end only).

CAP_PROP_PTS 
Python: cv.CAP_PROP_PTS

(read-only) FFmpeg back-end only - presentation timestamp of the most recently read frame using the FPS time base. e.g. fps = 25, VideoCapture::get(CAP_PROP_PTS) = 3, presentation time = 3/25 seconds.

CAP_PROP_DTS_DELAY 
Python: cv.CAP_PROP_DTS_DELAY

(read-only) FFmpeg back-end only - maximum difference between presentation (pts) and decompression timestamps (dts) using FPS time base. e.g. delay is maximum when frame_num = 0, if true, VideoCapture::get(CAP_PROP_PTS) = 0 and VideoCapture::get(CAP_PROP_DTS_DELAY) = 2, dts = -2. Non zero values usually imply the stream is encoded using B-frames which are not decoded in presentation order.

◆ VideoWriterProperties

enum cv::VideoWriterProperties

#include <opencv2/videoio.hpp>

cv::VideoWriter generic properties identifier.

See also
VideoWriter::get(), VideoWriter::set()
Enumerator
VIDEOWRITER_PROP_QUALITY 
Python: cv.VIDEOWRITER_PROP_QUALITY

Current quality (0..100%) of the encoded videostream. Can be adjusted dynamically in some codecs.

VIDEOWRITER_PROP_FRAMEBYTES 
Python: cv.VIDEOWRITER_PROP_FRAMEBYTES

(Read-only): Size of just encoded video frame. Note that the encoding order may be different from representation order.

VIDEOWRITER_PROP_NSTRIPES 
Python: cv.VIDEOWRITER_PROP_NSTRIPES

Number of stripes for parallel encoding. -1 for auto detection.

VIDEOWRITER_PROP_IS_COLOR 
Python: cv.VIDEOWRITER_PROP_IS_COLOR

If it is not zero, the encoder will expect and encode color frames, otherwise it will work with grayscale frames.

VIDEOWRITER_PROP_DEPTH 
Python: cv.VIDEOWRITER_PROP_DEPTH

Defaults to CV_8U.

VIDEOWRITER_PROP_HW_ACCELERATION 
Python: cv.VIDEOWRITER_PROP_HW_ACCELERATION

(open-only) Hardware acceleration type (see VideoAccelerationType). Setting supported only via params parameter in VideoWriter constructor / .open() method. Default value is backend-specific.

VIDEOWRITER_PROP_HW_DEVICE 
Python: cv.VIDEOWRITER_PROP_HW_DEVICE

(open-only) Hardware device index (select GPU if multiple available). Device enumeration is acceleration type specific.

VIDEOWRITER_PROP_HW_ACCELERATION_USE_OPENCL 
Python: cv.VIDEOWRITER_PROP_HW_ACCELERATION_USE_OPENCL

(open-only) If non-zero, create new OpenCL context and bind it to current thread. The OpenCL context created with Video Acceleration context attached it (if not attached yet) for optimized GPU data copy between cv::UMat and HW accelerated encoder.

VIDEOWRITER_PROP_RAW_VIDEO 
Python: cv.VIDEOWRITER_PROP_RAW_VIDEO

(open-only) Set to non-zero to enable encapsulation of an encoded raw video stream. Each raw encoded video frame should be passed to VideoWriter::write() as single row or column of a CV_8UC1 Mat.

Note
If the key frame interval is not 1 then it must be manually specified by the user. This can either be performed during initialization passing VIDEOWRITER_PROP_KEY_INTERVAL as one of the extra encoder params to VideoWriter::VideoWriter(const String &, int, double, const Size &, const std::vector< int > &params) or afterwards by setting the VIDEOWRITER_PROP_KEY_FLAG with VideoWriter::set() before writing each frame. FFMpeg backend only.
VIDEOWRITER_PROP_KEY_INTERVAL 
Python: cv.VIDEOWRITER_PROP_KEY_INTERVAL

(open-only) Set the key frame interval using raw video encapsulation (VIDEOWRITER_PROP_RAW_VIDEO != 0). Defaults to 1 when not set. FFmpeg back-end only.

VIDEOWRITER_PROP_KEY_FLAG 
Python: cv.VIDEOWRITER_PROP_KEY_FLAG

Set to non-zero to signal that the following frames are key frames or zero if not, when encapsulating raw video (VIDEOWRITER_PROP_RAW_VIDEO != 0). FFmpeg back-end only.

VIDEOWRITER_PROP_PTS 
Python: cv.VIDEOWRITER_PROP_PTS

Specifies the frame presentation timestamp for each frame using the FPS time base. This property is only necessary when encapsulating externally encoded video where the decoding order differs from the presentation order, such as in GOP patterns with bi-directional B-frames. The value should be provided by your external encoder and for video sources with fixed frame rates it is equivalent to dividing the current frame's presentation time (CAP_PROP_POS_MSEC) by the frame duration (1000.0 / VideoCapture::get(CAP_PROP_FPS)). It can be queried from the resulting encapsulated video file using VideoCapture::get(CAP_PROP_PTS). FFmpeg back-end only.

VIDEOWRITER_PROP_DTS_DELAY 
Python: cv.VIDEOWRITER_PROP_DTS_DELAY

Specifies the maximum difference between presentation (pts) and decompression timestamps (dts) using the FPS time base. This property is necessary only when encapsulating externally encoded video where the decoding order differs from the presentation order, such as in GOP patterns with bi-directional B-frames. The value should be calculated based on the specific GOP pattern used during encoding. For example, in a GOP with presentation order IBP and decoding order IPB, this value would be 1, as the B-frame is the second frame presented but the third to be decoded. It can be queried from the resulting encapsulated video file using VideoCapture::get(CAP_PROP_DTS_DELAY). Non-zero values usually imply the stream is encoded using B-frames. FFmpeg back-end only.

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