Repository: opencv
Issue: How to add more ffmpeg options
Labels: question (invalid tracker)

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##### System information (version)

- OpenCV => 4.5.5
- Operating System / Platform => Linux
- Compiler => gcc



##### Detailed description
Hi there , i wonder how to add  ffmpeg options to videocapture.
And  i found some answers like
```python
  import os
  os.environ["OPENCV_FFMPEG_CAPTURE_OPTIONS"] = "video_codec;h264_cuvid"
  cap = cv2.VideoCapture(url)
```
So how to add more options, like preset or anything else?



##### Steps to reproduce
I try below
```
        import os
        os.environ["OPENCV_FFMPEG_CAPTURE_OPTIONS"] = "video_codec;h264_cuvid|preset;slow"
        cap = cv2.VideoCapture(url)
```
but only fonud `h264_cuvid` in logs, i wonder that whether preset worked.
```
[OPENCV:FFMPEG:16] co located POCs unavailable
[DEBUG:0@3.046] global opencv-python/opencv/modules/videoio/src/cap_ffmpeg_impl.hpp (1056) open FFMPEG: stream[0] is video stream with codecID=27 width=2560 height=1920
[DEBUG:0@3.046] global opencv-python/opencv/modules/videoio/src/cap_ffmpeg_hw.hpp (933) HWAccelIterator FFMPEG: allowed acceleration types (none): ''
[DEBUG:0@3.046] global opencv-python/opencv/modules/videoio/src/cap_ffmpeg_impl.hpp (1113) open FFMPEG: Using video_codec='h264_cuvid'
```

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