XVID .avi w/ MP3 to .mp4 w/aac

[crash447]

I got to thinking that it would be nice to just convert the audio on my avi's from mp3 to aac so hopefully it would play on my iPod without converting the video. So here is what I did.

1) I extracted a wave file
2) encoded to aac in iTunes
3) Remultiplexed with YAMB
4) Played fine on PC
5) Synced to my iPod without problems

Now when I go play it on my iPod or with TV out it plays all jumbled, but the audio is fine and it looks normal when I fast forward (not that this really matters). Up until now anything I have successfully synced would play fine. So I kind of thought it would play since it synced. It seems I am so close I thought someone might have an idea.

I thought maybe there was some sort sort of setting I needed to check or something in YAMB.

Also if this should be in portable video feel free to move this, I just couldn't quite decide where it belonged more.

Thanks,
John

[celtic_druid]

So iPods can't handle mp3 audio in an mp4 container? MPEG-4 specs allow for mp3 audio and iPods can decode it.

[GMaq]

Hi,
I've done what your doing as well, the problem is that your AVI files have B frames in them, iPods don't playback MPEG-4 Video with B frames. To use DivX, XVid, 3ivx, Nero Digital, so called regular MPEG-4 Codecs you have to disable B frames in the encoder settings. In DivX it's called Bi-Directional Coding, 3ivX defaults to no B frames and XVid calls then B Frames, With Nero Digital you have to set "Quicktime Compatibility". Even though they sync to iPod's they won't playback, I learned this because I have a DivX Hardware Encoding capture device and thought great, all I have to do is capture and convert the audio only, All went well until I went to play them back on the iPod, Then I captured with I and P frames only and Voila perfect playback! Hope this helps !

[crash447]

Hi,
I've done what your doing as well, the problem is that your AVI files have B frames in them, iPods don't playback MPEG-4 Video with B frames. To use DivX, XVid, 3ivx, Nero Digital, so called regular MPEG-4 Codecs you have to disable B frames in the encoder settings. In DivX it's called Bi-Directional Coding, 3ivX defaults to no B frames and XVid calls then B Frames, With Nero Digital you have to set "Quicktime Compatibility". Even though they sync to iPod's they won't playback, I learned this because I have a DivX Hardware Encoding capture device and thought great, all I have to do is capture and convert the audio only, All went well until I went to play them back on the iPod, Then I captured with I and P frames only and Voila perfect playback! Hope this helps !

So otherwise if my file already has B frames the only choice is to reencode the video and I can't shorten the process? Thanks for the information.

John

[GMaq]

Yep,
Sorry to be the bearer of bad news, I know from some other threads that you've been messing around with H.264 as have I, You may find that re-encoding those AVI's to H.264 using a CQ setting rather than a set bitrate may give you good results, the only trick will be keeping the resolution size small enough that the Encoder doesn't overshoot the 1.5 mbps ceiling.