I am trying to adjust the frame rate -r fps of a video, and draw text which includes the new frame number -vf drawtext=text='frame %{frame_num} %{pts}'. Is this possible with a single invocation of ffmpeg?
例如，如果我尝试使用-
ffmpeg -i original.mp4 -r 25 -vf "drawtext=text='frame %{frame_num} %{pts}':x=10:y=10" output.mp4
when I play output.mp4, I see the frame rate indicted Input #0 25 fps is correct but the text frame 3000 is drawn at the 100s point which suggests 30 fps.
Can I modify the above single call to ffmpeg to correct the result or do I have to split the task in to two separate invocations of ffmpeg such as -
ffmpeg -i original.mp4 -r 25 temp.mp4
其次是
ffmpeg -i temp.mp4 -vf "drawtext=text='frame %{frame_num} %{pts}':x=10:y=10" output.mp4
