[FFmpeg-devel] [PATCH]HE-AACv1 try 3 (all missing functionality added)
Sat Feb 13 10:20:31 CET 2010
On Feb 12, 2010, at 3:15 PM, Alex Converse wrote:
> *A filterbank that supports float_to_int16_c as been added
> *All the computation time is spent in ff_sbr_apply() and it's
> children. If it isn't called from ff_sbr_apply() making it 100% faster
> isn't going to buy us anything.
> *No calls to lrintf depend on rounding behavior at (2*n+1)*0.5
> *Some sample SIMD placeholders are attached as a second patch.
> *Right now the synthesis filterbank is written on top on an MDCT. With
> appropriate SIMD functions it may make sense to move it to an FFT.
> Right now the MDCT version is much faster.
> *The analysis filterbank has been switched from an FFT to an RDFT.
I forgot this one:
> + if (sbr->start)
> + num_sbr_bits += sbr_data(ac, sbr, gb, id_aac);
> + num_align_bits = ((cnt << 3) - 4 - num_sbr_bits) & 7;
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