Besweet 5.1 AAC different bitrate for each channel

[kastro68]

I was wondering if it is possible to make Besweet encode the different channels at different bitrates.

eg. Use a lower bitrate for the rear channels and a higher bitrate for center and Front channels.

[KpeX]

BeSweet doesn't encode AAC. I'm assuming you're using BSN or AAC Machine in which case your AAC is encoded by psytel or Nero. I don't know offhand how 5.1 AAC bit allocation works in 5.1 VBR mode. Perhaps one of our 5.1 AAC experts could chime in here (Menno, tiki4, DG)?

[kastro68]

Originally posted by KpeX
BeSweet doesn't encode AAC. I'm assuming you're using BSN or AAC Machine in which case your AAC is encoded by psytel or Nero. I don't know offhand how 5.1 AAC bit allocation works in 5.1 VBR mode. Perhaps one of our 5.1 AAC experts could chime in here (Menno, tiki4, DG)?

You're right. My bad. Although nero does the encoding, I kind of assumed that Besweet was responsible for managing the channels. Without giving it much thought, I just assumed that nero encoded each channel differently and besweet put them together to make the 6 channels.

With hindsight, it is likely that something like joint stereo is at work...whereby similar information is kept as a base and any differences are allocated to the individual channels accordingly.

But then again, I know nothing about audio encoding.

I use the Oagmachine gui with besweet and the nero dlls.

[Tuning]

Hi kastro68,

The different AAC encoders already have bitrate adjustment. As you said like " Joint stereo encoding ", AAC uses M/S matrixing and intensity stereo.

Just a snap of two methods:
M/S matrixing: (Mid/Side stereo)
It is like joint stereo applied to front and surround channels.As we have seperate front/rear L & R, a matrix is applied to calculate relative sum and difference of original channels. Then this information is processed for creating final AAC file.Advantage, only the difference is encoded to seperate channels, saving bitrates.

Intensity stereo
Intensity stereo coding is a method that achieves a saving in bitrate by replacing left/right signals by a single representing signal plus directional information.


For more information on internal audio compression technology,
Refer http://www.audiocoding.com