Some AAC notes

[movmasty]

HowTo correctly avoid resampling problems with Nero AAC encoder in Besweet/Oagmachine
.........................
i now tested all possible sampling rates at specific bitrates with the following results:

CBR VBR

HE-AAC HE-AAC
mono stereo 5.1 stereo 5.1
8 24000 16 24000 40 24000 Tape 44100 Tape 44100
10 24000 20 24000 48 24000 Radio 44100 Radio 44100
12 32000 24 32000 64 32000 Internet 44100 Internet 44100
14 32000 28 32000 80 32000 Streaming 44100 Streaming 44100
16 44100 32 44100 96 44100
20 44100 40 44100 112 44100
24 44100 48 44100 128 44100
28 44100 56 44100 144 44100
32 44100 64 44100 160 44100
40 44100 80 44100 192 44100
48 44100 96 44100

LC-AAC LC-AAC
mono stereo 5.1 stereo 5.1
8 8000 16 8000 40 8000 Tape 24000 Tape 24000
12 11025 20 8000 48 11025 Radio 32000 Radio 32000
16 16000 24 11025 64 16000 Internet 44100 Internet 44100
20 16000 28 11025 80 16000 Streaming 44100 Streaming 44100
24 22050 32 16000 96 22050 Normal 44100 Normal 44100
28 24000 40 22050 128 24000 Extreme 44100 Extreme 44100
32 32000 48 22050 160 32000 Audiophile 44100 Audiophile 44100
40 32000 56 24000 192 32000 Transcoding 44100 Transcoding 44100
56 44100 64 32000 225 32000
64 44100 80 32000 256 44100
80 44100 96 32000 288 44100
96 44100 112 44100 320 44100
112 44100 128 44100 384 44100
128 44100 144 44100 480 44100
160 44100 160 44100 512 44100
192 44100
256 44100


i just made some encoding directly with nero wav editor, and HE profiles are accepting any sample rate, never downsampling, with difference from the LC mode,

at 16-20kb 44khz is very ugly, also in HE, so i first downsampled the wave to 22khz,
but nero HE upsampled the encoded AAC to 32khz,
so seems that 32khz is the correct rate for HE cbr 16 an 20kb.

another thing i noticed is that HE vbr profiles are accepting and encoding waves at 48khz,
thing that doesnt happen with any LC vbr profile.

[movmasty]

And now a question for an update on AAC audio in avi files,

ANY NEWS ????

ANY PROGRESS ????

and, what does it mean "Note that AVI is not recommended for AAC "
(from KpeX' Audio FAQs)

precisely what kind of problems there is?

syncro? playability? not audio at all??

I am very tired of mp3 for big-low size-quality, i'd like to try the AAC thing......i do? i dont have to ??

Any chance to find an acm for AAC?

I invoke the mighty forum for an answer. :thanks:

[check]

aac becomes bloated in avi, and has compatibility problems with certain decoders

[tebasuna51]

i just made some encoding directly with nero wav editor, and HE profiles are accepting any sample rate, never downsampling, with difference from the LC mode,

at 16-20kb 44khz is very ugly, also in HE, so i first downsampled the wave to 22khz,
but nero HE upsampled the encoded AAC to 32khz,
so seems that 32khz is the correct rate for HE cbr 16 an 20kb.

another thing i noticed is that HE vbr profiles are accepting and encoding waves at 48khz,
thing that doesnt happen with any LC vbr profile.
Yes, there are many changes from 2nd January 2004 Bond post.

The new free NeroAacEnc (also CT aacPlus), the HE-AAC+PS for low bitrate stereo encodings...

Of course Oagmachine is outdated, use BeLight, BeHappy, Foobar2000 ... instead.

[movmasty]

aac becomes bloated in avi, and has compatibility problems with certain decoders

what does it mean 'bloated' :confused:

[check]

Te overhead associated with storing AAC in AVI is very high compared to other codecs, even higher than with vorbis.