Bugs with MP4 Codec?

[GlynR]

I downloaded the MP4 codec which seems to work OK apart from a couple of strange occurrences. I wonder if these are bugs?

Both are when using the AAC HE V2 codec - which maybe not many people use.

1. All HEv2 rates worked OK - but for 8kbps it seemed to not compress the audio beyond what 56kbps did. All the others rates had smaller file sizes (and gradually worse audio quality) as expected, but 8kbps was far too good for the data rate selected, and file size was same as 56kbps sample.

2. Mono? I found the codec crashed if I tried to convert a mono wav file. Is this a limit of the AAC HEV2 codec spec or a bug? If I tried a two-channel mono file (ie left and right same audio) then it could convert it, but file size was same as a stereo file.

This isn't the end of the world for what I wanted, but I thought this feedback might be useful.

[Spoon]

Re: Bugs with MP4 Codec?

It is a very old page that one, see:

http://www.dbpoweramp.com/codec-central-m4a.htm

[GlynR]

Re: Bugs with MP4 Codec?

It is a very old page that one, see:

http://www.dbpoweramp.com/codec-central-m4a.htm

Thanks - it was first in the list on my Google search - I must try harder next time!

[GlynR]

Re: Bugs with MP4 Codec?

Thanks Spoon.
I've tried downloading that one from the link you gave. It has the same version number as the one I downloaded from the other page - and the same "bug" (if it is a bug)

[Spoon]

Re: Bugs with MP4 Codec?

With the new install you would convert to m4a FDK (AAC), you are doing this?

[GlynR]

Re: Bugs with MP4 Codec?

With the new install you would convert to m4a FDK (AAC), you are doing this?

Yep - then in next screen selecting the AAC HE v2 codec and the bitrate.

[Spoon]

Re: Bugs with MP4 Codec?

HEv2 is HE + PS, the PS stands for Parametric Stereo. It is not possible for a mono file to be encoded as PS.

Thanks for the heads up on 8KHz

[Spoon]

Re: Bugs with MP4 Codec?

m4a FDK (AAC) encoder updated to allow 8kbps encoding