Sometimes mp4 video might not be compatible with Final Cut Pro, that's because mp4 is just a container format, it's just the codec used inside might not be compatible.
Let's simply convert videos to a compatible format like x264 with FFmpeg:
# Convert video keep audio
ffmpeg -i input.mp4 -c:v libx264 -b:v 6000k -c:a copy output.mp4
# Convert video and audio
ffmpeg -i input.mp4 -c:v libx264 -b:v 6000k -c:a libfdk_aac output.mp4
- -i: input file
- -c:v libx264: Use x264 codec for video
- -b:v 6000k: Set video bitrate to 6000k
- -c:a copy: Copy audio codec
- -c:a libfdk_aac: Use aac codec for audio
- output.mp4: output file
And also we can do it in batch:
for i in *.mp4; do
ffmpeg -i "$i" -c:v libx264 -b:v 6000k -c:a copy "${i%.mp4}.x264.mp4" -y;
done
