Add OPENCV_FFMPEG_SKIP_LOG_CALLBACK to preserve custom FFmpeg logging #27864
OpenCV’s InternalFFMpegRegister overwrites av_log_set_callback, blocking custom FFmpeg log handlers in statically linked apps.
Add `OPENCV_FFMPEG_SKIP_LOG_CALLBACK` to let applications keep their own logging.
### Pull Request Readiness Checklist
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Optimize FFmpeg VideoCapture with swscale threads option #27755
### Pull Request Readiness Checklist
resolves https://github.com/opencv/opencv/issues/21969
* Switch to `sws_scale_from` for `libswscale >= 6.4.100` (FFmpeg >= 5.0)
* Use new context init API with threads option (`libswscale >= 8.12.100`: https://github.com/FFmpeg/FFmpeg/commit/2a091d4f2ee1e367d05a6bbbe96b204257cbda87)
* Replicate `sws_getCachedContext` with threads option for `libswscale < 8.12.100`
1 hour mp4 video every frame reading
| HW | sws_scale | sws_scale_frame + 16 threads | sws_scale_frame + 24 threads (#cpus) |
|---|---|---|---|
| Intel Core i9-12900 CPU | 45.1 sec | 25.4 sec (x1.77) | 30 sec (x1.50) |
| NVIDIA GPU 4090 | 232 sec | 89.4 sec (x2.59) | 77 sec (x3.01) |
```
import time
import numpy as np
import os
import cv2 as cv
# os.environ["OPENCV_FFMPEG_CAPTURE_OPTIONS"] = "hwaccel;cuvid|video_codec;h264_cuvid|vsync;0"
start = time.time()
video = "test.mp4"
cap = cv.VideoCapture(video, cv.CAP_FFMPEG)
while True:
has_frame, frame = cap.read()
if not has_frame:
break
print(time.time() - start)
```
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
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Patch to opencv_extra has the same branch name.
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[videoio][VideoWriter] Fix return code from CvVideoWriter_FFMPEG::writeFrame() when encapsulating encoded video #27737
Currently the return code from `CvVideoWriter_FFMPEG::writeFrame()` when `encode_video==true` (encapsulating raw encoded video) is wrong and results in the following warning implying it has been unsuccessful
> [ WARN:0@15.551] global cap_ffmpeg.cpp:198 write FFmpeg: Failed to write frame
### Pull Request Readiness Checklist
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libpng upgrade to 1.6.45 and cICP metadata support for PNG imwrite #27741
### Pull Request Readiness Checklist
resolves#24185
libpng docs: https://www.w3.org/TR/png-3/#cICP-chunk
similar code from ffmpeg: https://github.com/FFmpeg/FFmpeg/blob/a700f0f72d1f073e5adcfbb16f4633850b0ef51c/libavcodec/pngenc.c#L452-L456
So issue #24185 can be solved by replacing `cv.imwrite` in user's code to `cv.imwriteWithMetadata`:
```python
cv.imwriteWithMetadata("frame.png", frame, [cv.IMAGE_METADATA_CICP], np.array([[9, 18, 0, 1]], np.uint8))
```
```
$ exiftool /home/d.kurtaev/opencv_build/frames_pr/image_38.png
ExifTool Version Number : 12.76
File Name : image_38.png
Directory : /home/d.kurtaev/opencv_build/frames_pr
File Size : 3.8 MB
File Modification Date/Time : 2025:09:02 20:48:22+03:00
File Access Date/Time : 2025:09:02 20:48:22+03:00
File Inode Change Date/Time : 2025:09:02 20:48:22+03:00
File Permissions : -rw-r--r--
File Type : PNG
File Type Extension : png
MIME Type : image/png
Image Width : 1080
Image Height : 1920
Bit Depth : 8
Color Type : RGB
Compression : Deflate/Inflate
Filter : Adaptive
Interlace : Noninterlaced
Color Primaries : BT.2020, BT.2100
Transfer Characteristics : BT.2100 HLG, ARIB STD-B67
Matrix Coefficients : Identity matrix
Video Full Range Flag : 1
Image Size : 1080x1920
Megapixels : 2.1
```
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Patch to opencv_extra has the same branch name.
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fix: FFmpeg 8.0 support #27746
### Pull Request Readiness Checklist
related comment: https://github.com/opencv/opencv/pull/27691#discussion_r2322695640
See details at https://github.com/opencv/opencv/wiki/How_to_contribute#making-a-good-pull-request
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This aligns with other virtual method declarations in cap_dshow.hpp
and silences compiler warnings (-Wsuggest-override) while improving
compile-time safety.
Add strict validation for encoding parameters #27621
Close https://github.com/opencv/opencv/issues/27557
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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](https://github.com/FFmpeg/FFmpeg/blob/ee1f79b0fa4c82da9c19328b049b593c71611402/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
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FIX: CvCapture_FFMPEG::setProperty(CAP_PROP_POS_*) followed by getProperty #27523
Partially fixes#23088 and #23472. This PR fixes `get(CAP_PROP_POS_MSEC)` calls after a `set(CAP_PROP_POS_*)` without calling `read` first.
Since `seek` calls `grabFrame` which already sets `picture_pts`, manually setting `picture_pts` anywhere else in the call stack should not be necessary (except for the special case of seeking to frame 0).
Minimal example from #23088
```cpp
for(int i = 0; i < 3; i++) cap.read(img);
printf("at: %f frames, %f msec\n", cap.get(CAP_PROP_POS_FRAMES), cap.get(CAP_PROP_POS_MSEC));
cap.set(CAP_PROP_POS_FRAMES, 3);
printf("at: %f frames, %f msec\n", cap.get(CAP_PROP_POS_FRAMES), cap.get(CAP_PROP_POS_MSEC));
```
Current
```txt
at: 3.000000 frames, 80.000000 msec
at: 3.000000 frames, 0.234375 msec
```
PR
```txt
at: 3.000000 frames, 80.000000 msec
at: 3.000000 frames, 80.000000 msec
```
It similarly helps with `CAP_PROP_POS_MSEC`:
Current
```txt
at: 3.000000 frames, 80.000000 msec
at: 2.000000 frames, 6.250000 msec
```
PR
```txt
at: 3.000000 frames, 80.000000 msec
at: 2.000000 frames, 40.000000 msec
```
Note the seek operation is still inconsistent between the `CAP_PROP_POS_*` options as mentioned by #23088, and VFR video seeking has issues discussed in #9053. For fixed-frame rate video, we could change 0.5 to 1 in `void CvCapture_FFMPEG::seek(double sec);` to align `CAP_PROP_POS_MSEC` with `CAP_PROP_POS_FRAMES`, but `CAP_POS_AVI_RATIO` and VFR video would still be broken.
### Pull Request Readiness Checklist
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fix#26276: cv::VideoWriter fails writing colorless images #27153
When writing grayscale images (`isColor=false`), `cv::VideoWriter` failed as FFmpeg backend requires input frames to be in a grayscale format. Unlike other backends, FFmpeg doesn't perform this conversion internally and expects the input to be pre-converted. To fix this, I inserted a check in the `CvVideoWriter_FFMPEG_proxy::write` to convert input frames to grayscale when the input has more than 1 channel. If this is true, then the input is converted to a gray image using `cv::cvtColor` (with `cv::COLOR_BGR2GRAY`).
Additionally, as suggested in the issue comments, I have correctly propagated the return value of `CvVideoWriter_FFMPEG::writeFrame` back to the `CvVideoWriter_FFMPEG_proxy::write`. This return value wasn't being used, and `writeFrame` was always returning false since the FFmeg's return code `AVERROR(EAGAIN)` was mistakenly being treated as an error. Now it's handled as a signal for additional input (current input was successfully written, and a new frame should be sent. [See FFmpeg documentation for `avcodec_receive_packet`](https://ffmpeg.org/doxygen/6.1/group__lavc__decoding.html)). A warning is displayed if `CvVideoWriter_FFMPEG::writeFrame` returns false. Alternatively, this could be propagated back up to the user, making cv::VideoWriter::write a boolean.
Finally, I added a test case to verify if the grayscale conversion is being done correctly.
Fixes#26276
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Fix typos #27338
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Looks like UWP builds were broken on 5.x:
```
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,33): error C3646: 'size': unknown override specifier (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,37): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,33): error C3646: 'size': unknown override specifier (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\videoio_registry.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,37): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\videoio_registry.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,33): error C3646: 'size': unknown override specifier (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_bridge.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_capture.hpp(65,37): error C4430: missing type specifier - int assumed. Note: C++ does not support default-int (compiling source file C:\GHA-OCV-6\_work\opencv\opencv\opencv\modules\videoio\src\cap_winrt_bridge.cpp) [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
C:\Program Files (x86)\Windows Kits\10\bin\10.0.19041.0\XamlCompiler\Microsoft.Windows.UI.Xaml.Common.targets(486,5): error MSB4181: The "CompileXaml" task returned false but did not log an error. [C:\GHA-OCV-6\_work\opencv\opencv\build\modules\videoio\opencv_videoio.vcxproj]
```
Notes:
- Pipeline passes even though there are errors in the build
- I decided to remove _highgui_ WinRT backend, because it uses C-API which is has been removed in 5.x. I believe nobody uses it anyway.
- Change in anneal library is caused by the issue in WinAPI header - it does not declare two functions for UWP, even though documentation states compatibility. See also https://github.com/openssl/openssl/pull/18311https://learn.microsoft.com/en-us/windows/win32/api/memoryapi/nf-memoryapi-virtuallock
> Minimum supported client Windows XP [desktop apps | UWP apps]
> Minimum supported server Windows Server 2003 [desktop apps | UWP apps]
videoio: add Orbbec Gemini 330 camera support #27230
### Pull Request Readiness Checklist
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### Description of Changes
#### motivated：
- Orbbec has launched a new RGB-D camera — the Gemini 330. To fully leverage the capabilities of the Gemini 330, Orbbec simultaneously released version 2 of the open-source OrbbecSDK. This PR adapts the support for the Gemini 330 series cameras to better meet and respond to users’ application requirements.
#### change：
- Add support for the Orbbec Gemini330 camera.
- Fixed an issue with Femto Mega on Windows 10/11; for details, see [issue](https://github.com/opencv/opencv/pull/23237#issuecomment-2242347295).
- When enabling `HAVE_OBSENSOR_ORBBEC_SDK`, the build now fetches version 2 of the OrbbecSDK, and the sample API calls have been updated to the v2 format.
### Testing
| OS | Compiler | Camera | Result |
|:----------:|:---------------------------------------:|:-----------------:|:------:|
| Windows 11 | (VS2022) MSVC runtime library version 14.40 | Gemini 335/336L | Pass |
| Windows 11 | (VS2022) MSVC runtime library version 14.19 | Gemini 335/336L | Pass |
| Ubuntu22.04| GCC 11.4 | Gemini 335/336L | Pass |
| Ubuntu18.04| GCC 7.5 | Gemini 335/336L | Pass |
### Acknowledgements
Thank you to the OpenCV team for the continuous support and for creating such a robust open source project. I appreciate the valuable feedback from the community and reviewers, which has helped improve the quality of this contribution!
Zoom functionality for Android native camera capture #26837
### Pull Request Readiness Checklist
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Android camera refactoring #26646
This patch set does not contain any functional changes. It just cleans up the code structure to improve readability and to prepare for future changes.
* videoio(Android): Use 'unique_ptr' instead of 'shared_ptr'
Using shared pointers for unshared data is considered an antipattern.
* videoio(Android): Make callback functions private static members
Don't leak internal functions into global namespace. Some member
variables are now private as well.
* videoio(Android): Move resolution matching into separate function
Also make internally used member functions private.
* videoio(Android): Move ranges query into separate function
Also remove some unneccessary initialisations from initCapture().
* videoio(Android): Wrap extremly long source code lines
* videoio(Android): Rename members of 'RangeValue'
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Fixed default cap_prop_orientation_auto behaviour #26800
Fixes : #26795
### Pull Request Readiness Checklist
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AndroidMediaNdkVideoWriter pixel format enhancement #26698
* videoio(Android): Add source pixel formats RGBA and GRAY to AndroidMediaNdkVideoWriter
Let AndroidMediaNdkVideoWriter::write() deduce source pixel format from matrix type:
CV_8UC3 -> BGR (as before)
CV_8UC4 -> RGBA (use in conjunction with CvCameraViewFrame)
CV_8UC1 -> GRAY
* samples/android/video-recorder: Send images to VideoWriter in RGBA format
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AndroidMediaNdkCapture pixel format enhancement #26656
### Pull Request Readiness Checklist
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Open VideoCapture from data stream #25584
### Pull Request Readiness Checklist
Add VideoCapture option to read a raw binary video data from `std::streambuf`.
There are multiple motivations:
1. Avoid disk file creation in case of video already in memory (received by network or from database).
2. Streaming mode. Frames decoding starts during sequential file transfer by chunks.
Suppoted backends:
* FFmpeg
* MSMF (no streaming mode)
Supporter interfaces:
* C++ (std::streambuf)
* Python (io.BufferedIOBase)
resolves https://github.com/opencv/opencv/issues/24400
- [x] test h264
- [x] test IP camera like approach with no metadata but key frame only?
- [x] C API plugin
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.
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- [x] The PR is proposed to the proper branch
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Patch to opencv_extra has the same branch name.
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V4l default image size #25500
Added ability to set default image width and height for V4L capture. This is required for cameras that does not support 640x480 resolution because otherwise V4L capture cannot be opened and failed with "Pixel format of incoming image is unsupported by OpenCV" and then with "can't open camera by index" message. Because of the videoio architecture it is not possible to insert actions between CvCaptureCAM_V4L::CvCaptureCAM_V4L and CvCaptureCAM_V4L::open so the only way I found is to use environment variables to preselect the resolution.
Related bug report is [#25499](https://github.com/opencv/opencv/issues/25499)
Maybe (but not confirmed) this is also related to [#24551](https://github.com/opencv/opencv/issues/24551)
This fix was made and verified in my local environment: capture board AVMATRIX VC42, Ubuntu 20, NVidia Jetson Orin.
### Pull Request Readiness Checklist
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Patch to opencv_extra has the same branch name.
- [ ] The feature is well documented and sample code can be built with the project CMake
Fix VideoCapture fails to read single image with digits in name #26637
### Pull Request Readiness Checklist
Fix#26457
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
Android camera feature enhancements #26627
Closes https://github.com/opencv/opencv/issues/24687
### 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
- [ ] The PR is proposed to the proper branch
- [ ] 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
Support C++20 standard #26590
Close https://github.com/opencv/opencv/issues/26589
Related https://github.com/opencv/opencv_contrib/pull/3842
Related: https://github.com/opencv/opencv/issues/20269
- do not arithmetic enums and ( different enums or floating numeric)
- remove unused variable
### 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
Alexander Smorkalov
Peter Rekdal Khan-Sunde
Dimitre
cudawarped
Dmitry Kurtaev
Alexander Smorkalov
Ansh Swaroop
Kumataro
Yan Wen
Sachin Shah
Francisco Mónica
omahs
Maksim Shabunin
sirudoi
Rüdiger Ihle
Skreg
UnnamedOrange
Vincent Rabaud
alex-urm
Maxim Smolskiy
dai-xin
Alexander Alekhin