AAC Encoder Bitrate limited to ~130 kbps [#21904]

[telecore]

The majority of my music library is in M4A/ALAC format - when I sync to my iphone, or an external USB drive and set it to transcode to M4A/AAC at VBR/100%, all the files seem to end up at about ~130 kbps - according to the program, VBR/100% should be about 210 kbps - can anyone explain what is going on here?

[MiPi]

Thanks for the info, there is regression bug in aac encoder in the last version of MM codec pack, I will look at it with the highest priority and fix soon as https://www.ventismedia.com/mantis/view.php?id=21904

[telecore]

OK - I just performed a test and codec pack 3.0.10 seems to achieve the higher bitrates that would be expected with VBR 100% - 3.0.11 has the problem

[Peke]

Hi,
We have updated https://www.ventismedia.com/mantis/view.php?id=21904 can you confirm same behavior?

[telecore]

That is exactly what I did - I compared files encoded with 3.0.10 and 3.0.11 with MediaInfo and clearly the 3.0.11 signal file size and bit rate were much lower

I don't think that you can conclude that the quality of the lower bitrate 3.0.11 encoder is the same as the 3.0.10 encoder by comparing time domain waveforms of a single test signal - if 3.0.11 is using the same faac encoder as 3.0.10 and different bit rates are produced at the vbr 100% setting, then something is wrong

BTW - is there any chance of supporting the qaac encoder instead of faac?

[telecore]

One more thing to report - it looks like MM2024 M4A/AAC encoded files (with 3.0.10) now play without errors on Denon Home Speakers and Denon AVRs - not sure if the codec pack update or a Denon HEOS update fixed this but it appears to work

EDIT: I see that codec pack 3.0.12 exists with some enhancements - please make it available for us users - thanks!

[rusty]

We released 3.0.12 today in order to fix the issues described at https://www.ventismedia.com/mantis/view.php?id=21904 (i.e. failure to encode for some formats, and inability to encode at > 140 kbps for VBR @ 100%.

We didn't make any changes to the codec settings when it comes to VBR. i.e. 100% VBR still encodes to ~140kbps since this was the estimated equivalent setting of the faac authors. However, it's now possible to set the encoder to above 100% (up to 1000%) if you want to target a higher average kbps.

Note also that in addition to being more efficient, the new version is faster.

-Rusty

[rusty]

And to answer your question about qaac vs faac, we can have a look--not sure about the licensing.

-Rusty

[Peke]

BTW - is there any chance of supporting the qaac encoder instead of faac?

Hmm Interesting, maybe like @rusty said we could make similar testing to https://hydrogenaudio.org/index.php/topic,120759.0.html while we investigate licenses.