ffmpeg - how to merge multiple audio with time offset into a video? [closed]

Answer 1

Thanks to Mulvya's solution. Here are extra info for how to mix multiple audio stream with delay requirement:

ffmpeg -i 1.mp3 -i 1.3gp -i 2.3gp -i 3.3gp -i 4.3gp -i 5.3gp -i 1.mp4 \ 
-filter_complex "[2]adelay=2790|2790[s2];\
[3]adelay=10300|10300[s3];\
[4]adelay=14930|14930[s4];\
[5]adelay=21090[s5];\
[0][1][s2][s3][s4][s5]amix=6[mixout]" \
-map 6:v -map [mixout] -c:v copy result.mp4

The difficult part is: [2]adelay=2790|2790[s2] . it means 'select 3rd input, give 2,79sec delay and ouput as s2', the 's2' is used in following 'amix' command to generate a '6[mixout]' which is used then in '-map'.

Answer 2

You have to mix the audio streams:

ffmpeg -i 1.mp4 -i 1.3gp -i 2.3gp -i 1.mp3
  -filter_complex "[2]adelay=10000|10000[s2];[3:a][1:a][s2]amix=3[a]"
  -map 0:v -map "[a]" -c:v copy result.mp4