HydrogenAudio

Lossy Audio Compression => AAC => AAC - General => Topic started by: gvinu4u on 2012-06-29 04:18:29

Title: Audio 24 Bit: Different Codec Files Required
Post by: gvinu4u on 2012-06-29 04:18:29
Hi all.

Can any one help me in getting these files or atleast how to generate these

AAC LC , 24 bit per sample, 5.1 channel
HEAAC, 6 channel
HEAAC, 6 channel, 24 bit per sample, 48k Sample rate
HEAAC, 6 channel, 24 bit per sample, 96k Sample rate
EAAC+, 24 bit per sample, stereo


Thanks
Guru
Title: Audio 24 Bit: Different Codec Files Required
Post by: benski on 2012-06-29 04:52:37
bits-per-sample is not applicable to the AAC codec.  Output is depending on the decoding algorithm used, usually 32-bit IEEE floating point or 16.16 fixed point.  The output would be decimated to the appropriate bits per sample (usually 16 or 24) before sending to the soundcard.
Title: Audio 24 Bit: Different Codec Files Required
Post by: slks on 2012-07-03 20:26:08
Like the other guy said, AAC audio itself doesn't have a bit depth, although it's certainly possible to feed a 24-bit input file to the encoder.

I don't know of any place that has all these different formats sitting out and ready to go, so you'll probably need to encode them yourself.

Firstly, of course, you need to have some audio samples to encode. Once you've got that, you just need to feed them to a suitable encoder. There are several, but the easiest to use would probably be the Nero encoder, which is available on this forum under the "AAC" subforum. It's capable of generating LC-AAC, HE-AAC, and HEv2-AAC (aka EAAC+) in stereo and six channels. See the documentation/readme for what particular command line to use for your desired output.

It's been a while since I used Nero, so I don't remember if it can do 5.1-to-stereo downmixing or resampling on the fly. So you may need to do that yourself before encoding them. It's hard to get any more specific without knowing exactly what you're trying to accomplish.