Add Raspberry Pi 4 and 5 V4L2 Stateless HEVC Hardware Acceleration with FFmpeg #27453
This PR enables V4L2 stateless HEVC hardware acceleration for Raspberry Pi 5 within OpenCV's videoio module. It leverages FFmpeg's drm acceleration ([FFmpeg API changes](ee1f79b0fa/doc/APIchanges (L1529))), significantly improving HEVC decoding performance on RPi5 for robotics and embedded vision applications.
I have a working proof-of-concept with local benchmarks showing clear gains.
Checklist Status:
Ready: License, branch (4.x), FFmpeg reference, and (linked) related issue (#27452).
Seeking Guidance: Need help with formal C++ performance/accuracy tests, opencv_extra integration, and full documentation/examples.
As a Python developer, I welcome C++ best practice feedback and assistance with testing setup.
### 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
- [ ] There is accuracy test, performance test and test data in opencv_extra repository, if applicable
Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
videoio: HW decode/encode in FFMPEG backend; new properties with support in FFMPEG/GST/MSMF
* HW acceleration in FFMPEG backend
* fixes on Windows, remove D3D9
* HW acceleration in FFMPEG backend
* fixes on Windows, remove D3D9
* improve va test
* Copyright
* check LIBAVUTIL_BUILD >= AV_VERSION_INT(55, 78, 100) // FFMPEG 3.4+
* CAP_MSMF test on .mp4
* .mp4 in test
* improve va test
* Copyright
* check LIBAVUTIL_BUILD >= AV_VERSION_INT(55, 78, 100) // FFMPEG 3.4+
* CAP_MSMF test on .mp4
* .mp4 in test
* .avi for GStreamer test
* revert changes around seek()
* cv_writer_open_with_params
* params.warnUnusedParameters
* VideoCaptureParameters in GStreamer
* open_with_params
* params->getUnused
* Reduce PSNR threshold 33->32 (other tests use 30)
* require FFMPEG 4.0+; PSNR 30 as in other tests
* GStreamer AVI-demux plugin not installed in Ubuntu test environment?
* fix build on very old ffmpeg
* fix build on very old ffmpeg
* fix build issues
* fix build issues (static_cast)
* FFMPEG built on Windows without H264 encoder?
* fix for write_nothing test on VAAPI
* fix warnings
* fix cv_writer_get_prop in plugins
* use avcodec_get_hw_frames_parameters; more robust fallback to SW codecs
* internal function hw_check_device() for device check/logging
* two separate tests for HW read and write
* image size 640x480 in encode test
* WITH_VA=ON (only .h headers used in OpenCV, no linkage dependency)
* exception on VP9 SW encoder?
* rebase master; refine info message
* videoio: fix FFmpeg standalone plugin build
* videoio(ffmpeg): eliminate MSVC build warnings
* address review comments
* videoio(hw): update videocapture_acceleration.read test
- remove parallel decoding by SW code path
- check PSNR against the original generated image
* videoio: minor fixes
* videoio(test): disable unsupported MSMF cases (SW and HW)
* videoio(test): update PSNR thresholds for HW acceleration read
* videoio(test): update debug messages
* "hw_acceleration" whitelisting parameter
* little optimization in test
* D3D11VA supports decoders, doesn't support encoders
* videoio(test): adjust PSNR threshold in write_read_position tests
* videoio(ffmpeg): fix rejecting on acceleration device name mismatch
* videoio(ffmpeg): fix compilation USE_AV_HW_CODECS=0, add more debug logging
* videoio: rework VideoAccelerationType behavior
- enum is not a bitset
- default value is backend specific
- only '_NONE' and '_ANY' may fallback on software processing
- specific H/W acceleration doesn't fallback on software processing. It fails if there is no support for specified H/W acceleration.
* videoio(test): fix for current FFmpeg wrapper
Co-authored-by: Alexander Alekhin <alexander.a.alekhin@gmail.com>
