Revert the commit where parameter int cn (number of channels) was
replaced with int type (e.g: CV_8UC1) to preserve external API
compatibility. All realted logging and tests were updated accordingly.
Replaces implicit data manipulation with a warning-based approach.
Following reviewer feedback, data conversion is now explicitly
left to the user, and no automatic transformations are performed
in writeFrame().
Aligns FFmpeg backend behavior with MS Media Foundation and Android,
by moving the internal conversion logic to writeFrame().
This now handles all relevant format conversions:
- CV_8UC3 -> CV_8UC1 or CV_16UC1
- CV_8UC1 -> CV_8UC3 or CV_16UC1
- CV_16UC1 -> CV_8UC1 or CV_8UC3
It still corrects AVERROR(EAGAIN) handling, which was previously
misinterpreting it as an error and displays a warning when
writeFrame returns false. Adds more test cases ensuring all
possible conversions are properly tested.
The internal return values of the FFmpeg library are now correctly
handled in the FFmpeg backend. The writeFrame function now considers
that the FFmpeg return code AVERROR(EAGAIN) indicates the encoder needs
more input, so a new frame must be sent instead of treating it as a
real error. Additionally, the return value of
CvVideoWriter_FFMPEG::writeFrame is now properly propagated back to the
write function in the cap_ffmpeg.cpp file, which displays a warning
when writeFrame returns false. Additionally, a conversion of the input
to grayscale was implemented before entering FFmpeg backend, as the
encoder expects grayscale frames when isColor=false. This requires
converting from CV_8UC3 to grayscale (a simple color conversion is done
here using the cvtColor function). Finally, a new test case has been
implemented to verify that the grayscale conversion is correctly
applied.
videoio: print test params instead of indexes #26948
_videoio_ test names changed - use string instead of index.
E.g. `videoio_read.threads/0` is now `videoio_read.threads/h264_0_RAW`.
It allows to filter tests independently of the platform.
**Notes:**
- not all tests has been updated - only simpler ones and those which have varying parameters depending on platform
videoio: fix cv::VideoWriter with FFmpeg encapsulation timestamps #25874
Fix https://github.com/opencv/opencv/issues/25873 by modifying `cv::VideoWriter` to use provided presentation indices (pts).
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake
videoio: Add raw encoded video stream muxing to cv::VideoWriter with CAP_FFMPEG #24363
Allow raw encoded video streams (e.g. h264[5]) to be encapsulated by `cv::VideoWriter` to video containers (e.g. mp4/mkv).
Operates in a similar way to https://github.com/opencv/opencv/pull/15290 where encapsulation is enabled by setting the `VideoWriterProperties::VIDEOWRITER_PROP_RAW_VIDEO` flag when constructing `cv::VideoWriter` e.g.
```
VideoWriter container(fileNameOut, api, fourcc, fps, { width, height }, { VideoWriterProperties::VIDEOWRITER_PROP_RAW_VIDEO, 1 });
```
and each raw encoded frame is passed as single row of a `CV_8U` `cv::Mat`.
The main reason for this PR is to allow `cudacodec::VideoWriter` to output its encoded streams to a suitable container, see https://github.com/opencv/opencv_contrib/pull/3569.
### Pull Request Readiness Checklist
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
- [x] I agree to contribute to the project under Apache 2 License.
- [x] To the best of my knowledge, the proposed patch is not based on a code under GPL or another license that is incompatible with OpenCV
- [x] The PR is proposed to the proper branch
- [x] There is a reference to the original bug report and related work
- [x] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [x] The feature is well documented and sample code can be built with the project CMake
* Allow the number of threads FFMpeg uses to be selected during VideoCapture::open().
Reset interupt timer in grab if
err = avformat_find_stream_info(ic, NULL);
is interupted but open is successful.
* Correct the returned number of threads and amend test cases.
* Update container test case.
* Reverse changes added to existing videoio_container test case and include test combining thread change and raw read in the newly added videoio_read test case.
Add capacity to Videocapture to return the extraData from FFmpeg when required
* Update rawMode to append any extra data recieved during the initial negotiation of an RTSP stream or during the parsing of an MPEG4 file header.
For h264[5] RTSP streams this ensures the parameter sets if available are always returned on the first call to grab()/read() and has two purposes:
1) To ensure the parameter sets are available even if they are not transmitted in band. This is common for axis ip camera's.
2) To allow callers of VideoCapture::grab()[read()] to write to split the raw stream over multiple files by appending the parameter sets to the begining of any new files.
For (1) there is no alternative, for (2) if the parameter sets were provided in band it would be possible to parse the raw bit stream and search for the parameter sets however that would be a lot of work when that information is already provided by FFMPEG.
For MPEG4 files this information is only suplied in the header and is required for decoding.
Two properties are also required to enable the raw encoded bitstream to be written to multiple files, these are;
1) an indicator as to whether the last frame was a key frame or not - each new file needs to start at a key frame to avoid storing unusable frame diffs,
2) the length in bytes of the paramater sets contained in the last frame - required to split the paramater sets from the frame without having to parse the stream. Any call to VideoCapture::get(CAP_PROP_LF_PARAM_SET_LEN) returning a number greater than zero indicates the presense of a parameter set at the begining of the raw bitstream.
* Adjust test data to account for extraData
* Address warning.
* Change added property names and remove paramater set start code check.
* Output extra data on calls to retrieve instead of appending to the first packet.
* Reverted old test case and added new one to evaluate new functionality.
* Add missing definition.
* Remove flag from legacy api.
Add property to determine if returning extra data is supported.
Always allow extra data to be returned on calls to cap.retrieve()
Update test case.
* Update condition which indicates CAP_PROP_CODEC_EXTRADATA_INDEX is not supported in test case.
* Include compatibility for windows dll if not updated.
Enforce existing return status convention.
* Fix return error and missing test constraints.
add video capture parameters
* add parameters
* videoio: revert unnecessary massive changes
* videoio: support capture parameters in backends API
- add tests
- FFmpeg backend sample code
- StaticBackend API is done
- support through PluginBackend API will be added later
Co-authored-by: Milashchenko <maksim.milashchenko@intel.com>
Co-authored-by: Alexander Alekhin <alexander.a.alekhin@gmail.com>
- Added test for automated rotation for MP4 videos with metadata
- Fix 180 degrees rotation bug
- Moved rotation logic to cv::VideoCapture implementation for FFmpeg and restore binary compatibility with FFmpeg wrapper.
* feature: Add video capture bitrate read-only property for FFMPEG backend
* test: For WIN32 property should be either expected or 0.
Added `IsOneOf` helper function, enabled only for _WIN32.
Add retrieve encoded frame to VideoCapture
* Add capacity to retrieve the encoded frame from a VideoCapture object.
* Correct raw codec and pixle format output from ffmpeg capture.
* Remove warnings from build.
* Added VideoCaptureRaw subclass.
* Include abstract base class VideoCaptureBase and rename new subclass VideoContainer as suggested by mshabunin.
* Remove using.
* Change base class name for compatibility with jave bindings generator.
* Move grab and retrieve and add override specifier
* Add setRaw and readRaw to IVideoCapture interface
-setRaw to disable video decoding and enable bitstream filters from mp4 to h254 and h265.
-readRaw to return the raw undecoded/filtered bitstream.
Add createRawCapture to initiate a backend with setRaw enabled.
Remove inheritance and use an independant VideoContainer subclass with IVideoCapture member.
* Address unused parameter warings.
Remove VideoContainer from python bindings as it no longer returns a Mat.
Use opencv type uchar instead of unsigned char.
Add missing destructor to VideoContainer class.
* Address build warnings and include all params in documentation.
* Include deprecated bitstream filtering API.
* Update codec_id query to work with older ffmpeg api's.
Change api version defines to be consistent - most recent api version first.
* Fix typo.
* Update test to work with naming of new files in the extra repo
* Investigate test failure
* Check bytes read by ffmpeg
* Removed mp4 video container test
* Applied suggested changes.
* videoio: rework API for extraction of RAW video streams
- FFmpeg only
* address review comments
