audio encoders in avidemux

[mbur]

Does anyone have any thoughts to offer on acceptable settings when encoding music with avidemux et al.

I'm uploading videos to Youtube and have issues with the audio quality achieved.

The source material comes from an archos 5 which uses Microsoft IMA ADPCM audio encoding at 48000Hz. (387kbps data rate) and has a DIVX 6.9.2 video codec. (2478kbps).

To speed up the upload (and save space) I re-encode using Avidemux's MPEG-4 AVC (x264) encoder. For some reason I can only safely use the MP4 container format and this forces me to re-encode the audio using MP3.

For a 3 minute clip this brings the file size down from 60,000 KB to 7,500 KB. with the audio content down from 8,000 to 3,000 KB. The video is good enough but the audio is noticeably distorted.

The mp3 audio sample rate is 48000 Hz (no change there) but the data rate is 128kbps c/f the 387kbps for the source. I did once increased the mp3 data rate to 320kbps but the result was still not as good as the original.

Is there a better audio encoder 'out there'?

[poisondeathray]

At the same bitrate, AAC is slightly better than MP3 . But if you already tried 320kbps MP3, there probably isn't much you can do .

Are you comparing the quality before you upload to youtube, or youtube's version ?

Does youtube accept ADPCM audio ? or AVC in AVI container ? If they do , you could use yamb to extract raw video then AVC2AVI with the avidemux encoded video ; then you can mux the original audio into same AVI container with AVIMux-GUI . You can't get better than the original audio , then the only quality loss would be from YT re-encoding it , but you can't control that

[mbur]

I'm comparing the file I'm uploading to the source. Youtube's version is accurate to what it receives.
I suppose my ideal situation would be to keep the original sound but I can't find a container that will take both AAC and x264. I'm using x264 because it is fast and makes my files way smaller than everything else I've tried. I also have the problem that sometimes the source sound level is way too low and some amount of re-encoding is inevitable.

'Does youtube accept ADPCM audio' I think they might. It will take me about a week to check out your suggestion. Thanks! I'll be back!

[bat999]

Hi
According to this website YouTube does allow ADPCM. Here:-http://wiki.multimedia.cx/index.php?title=YouTube

So you could use the 'copy' function for the audio and use mkv container.

[mbur]

Well this is promising.. I hadn't even noticed the mkv container lurking just above the bottom of the list (I wonder what 'dummy' does). Did a recode using aac at 384kbps and auto gain mode filter to fix the level issue. The warbles are gone. Thanks for that bat!