Having an issue with PAL audio.

[cthane]

Greetings, everyone!


I am trying to convert a pal video to ntsc but I am having an issue with the audio. I successfully converted the video to NTSC but the audio is out of sync with the video. I used to Adobe Audition to stretch the audio to match the duration of the video but it is still out of sync. What should I do?

[jagabo]

The audio and video in an AV file don't have to start at the same time, have the same length, or end at the same time. You have to account for all of those issues.

Beyond that, you may have done the conversion wrong. There are many ways to perform frame rate conversions. Some programs don't work right with variable frame rate video. Etc.

[ProWo]

Oops, I just saw that you re-encoded the video yourself; did you just change the frame rate and leave the movie duration the same, or did you change the duration as well?
This is important for further help.

[cthane]

I changed the frame rate and the duration is 4 minutes longer. I should also mention that when I play the new audio with the video it is in sync for about 20 minutes and then after that it goes out of sync.

[jagabo]

I changed the frame rate and the duration is 4 minutes longer.

Just to be sure, so the entire source was about 100 minutes?

I should also mention that when I play the new audio with the video it is in sync for about 20 minutes and then after that it goes out of sync.

Suddenly out of sync? Or gradually over the entire movie? How far is it out of sync at the end?

[ProWo]

Could you post a mediainfo report (text mode) from both videos (PAL & NTSC) here?

[cthane]

Here you go!

[davexnet]

I did something like this for a movie once; with PAL and NTSC elements.

Both videos had the same scenes but the little gaps between scenes were longer/shorter
and this is where it was going out.

I had a good result using Avisynth and vdub2, more details here:
https://forum.videohelp.com/threads/410976-Syncying-movie-sound-when-one-video-is-slightly-faster

[ProWo]

Here you go!

OK.
Download clever FFmpeg-GUI, start it, follow the instructions, then load your PAL video, click main, click encode audiostream, click encoder.
Set all like in the picture below and click encode.
The new generated ac3 audio should match the encoded 23.976 fps lagarith video.


[Attachment 77923 - Click to enlarge]