>
> Some time ago, we discussed about the decoder size wich was problematic when
> using 320k frames.
>
> According to the iso doc, the buffer size is different for each sampling
> frequency:
> 48000: 7680
> 44100: 8360
> 32000: 11520
>
> So it's possible to use the full frame at 44.1/320k.
> However, bit reservoir use is forbidden in a 320k frame, as main_data_begin
> must be set to 0. But the next frame, if it's not a 320k one, can use bit
> reservoir from this 320k frame.
>
I think most decoders will agree, and allow any size buffer allowed by
mean frame length + main_data_begin. But check out section 2.4.3.4.4:
"at sampling frequencies lower than 48kHz the buffer should be
constrained such that the same physical buffer size is sufficient
as the one calculated for the 48kHz case above"
"the one calculated for the 48kHz case above" is 7680 bits.
Someone on the mpg123 mailing list speculated that the buffer
refered to the buffer for one granule of one channel
(about 1/4 the frame size) rather than the whole frame, but
the standard really doesn't say.
Mark
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