Comparing compressibility of audio codecs.

[PuzZLeR]

I've still got a lot to learn with audio encoding so bear with me if this question seems rather n00by-ish. I honestly can't seem to find any direct info on this.

What are the compressibility ratios like when comparing certain audio codecs?

For example, I've heard that AAC is twice as efficient as MP3 - same quality in half the file size or double the quality in same file size.

I'm particularly interested in comparing AAC, MP3 and AC3. If someone can offer info on MP2, WAV or DTS that would be cool too. Let's assume 2 channels for now.

Lots of info on video codecs on this, but hazy with audio.

:thanks: in advance!

[nurbs]

You could head over to hydrogenaudio.org. In the wiki there you can find results for listening test of different codecs at various bitrates. They mostly have info about mp3, aac, vorbis and wma. There is also info on how to do your own abx test.

[prOnorama]

You might want to check out the Hydrogenaudio Forums (http://www.hydrogenaudio.org/forums/index.php) if you're looking for comparisons and a lot of info on lossy/lossless audio codecs.

[shon3i]

For example, I've heard that AAC is twice as efficient as MP3 - same quality in half the file size or double the quality in same file size.Well it is simply false because you can't compare just like that. HE-AAC will be always superior than MP3 at low-mid bitrates (16-96kbps).

but realy LC-AAC is almost 30% better than mp3 on mid-high bitrates such 128-192kbs, and HE-AAC is 30% better that mp3Pro. on higher bitrates the percent is much smaller. The one importat thing that is AAC much safer to use if you want qualty, because MP3 sometimes have big problems with samples even on 320kbps.

[delacroixp]

I'm particularly interested in comparing AAC, MP3 and AC3. If someone can offer info on MP2, WAV or DTS that would be cool too. Let's assume 2 channels for now.

DTS is probably the most superior DVD audio format, certainly when it comes to Mpeg2 material.
Unfortunately open-source support is limited and transcoding 5.1 DTS -> MP4 surround is problematic.


:):devil::D
Pascal