iPhone vertical videos

[leicao-me]

The output video from iPhone "vertical" video (height > width) inputs will be rotated by 90 degrees counter-clockwise by Darknet automatically. Thus, the detection works very bad on the rotated videos.

Note:

1. Those videos that have this problem are taken by iPhone directly. Those vertical videos generated or edited and saved by social media apps have no such problem.
2. Horizontal videos (width > height) have no such problem.
3. Tested on iPhone 7 Plus and iPhone X.

Is there a way to auto-detect such videos and rotate them in the darknet, or can someone provide a workaround solution, please?

One can test this problem by visiting my project website and upload a vertical video from your iPhone: http://objectdetect.pro

Please upload videos with no potential privacy issues. You can overwrite your previous video by uploading a new video. Previous videos are not saved in the server.

Thank you

[leicao-me]

No one experience the same error?

[AlexeyAB]

You should add your code:

• check rotation of smartphone or videostream (I don't know how to do this) - and set this values rotation_is_required=1 or 0

• then rotate each frame, to do it, between these 2 lines: https://github.com/AlexeyAB/darknet/blob/08e8e0c8c2d3cddfb6ee065e813ae5023f9568d2/src/http_stream.cpp#L240-L241 add this code:

          int rotation_is_required = 1;
          if (rotation_is_required) {
              cv::Mat dst;
              //cv::flip(frame.t(), dst, 1);  // clockwise 90 degree rotation
              cv::flip(frame.t(), dst, 0);    // counter-clockwise 90 degree rotation
              frame = dst;
          }