How are the 448 kbps in ac3 split on channels

[NomenNescio]

How are the 448 kbps in ac3 (5.1) split on the 6 channels.
MP3 128 kbps stereo for exapmle is split in 64 kbps/channel

[JimJohnD]

Save this link, it's a PDF file of the AC3 (Digital Dolby) spec. It should have all of the details you could ask for.

http://www.atsc.org/standards/a_52a.pdf

In Section 7.2.1 it states:
"There are no preassigned exponent or mantissa bits, allowing
the routine to flexibly allocate bits across channels, frequencies, and audio blocks in accordance
with signal demand."

And in 8.2.12 it states:
"Bits are allocated globally from a common bit pool to all channels."

Hope that helps....

[Skynet107]

In other words, bits are shared between all channels to maximize quality. So if there is sound in only one channel, the entire bitstream can be used up for just that one channel. It is adaptive, always changing.