I need to concatenate some MP4 files. Only one of them has audio. The other ones hasn't.
MyList.txt contains: file1.mp4 without audio and 5s length File2.mp4 without audio and 5s length File3.mp4 without audio and 5s length File4.mp4 with audio and Ns length
I need an output that cotains the 4 mp4 files and when file4.mp4 starts I want to hear its audio.
If I set the file4.mp4 as the first video to concat, the output video has audio, but If I set the file4.mp4 in another position, the output video hasn't audio.
What I'm doing wrong? What I have to modify in my code?
ffmpeg -f concat -safe 0 -i myList.txt -c:v copy -c:a copy output.mp4