[FFmpeg-devel] [PATCH 0/5][RFC] Speed up AAC decoder

Mans Rullgard mans
Mon Jan 11 13:37:44 CET 2010

This patch series speeds up the AAC decoder by 25-50% on Cortex-A8 and
by 20-30% on Core i7.

Some of the more obscure parts certainly need a few comments, which I
will add if there are no objections to this approach.

Mans Rullgard (5):
  AAC: use table for cbrtf(n)*n
  AAC: Compress codebook tables and optimise sign bit handling
  AAC: simplify some calculations in decode_spectrum_and_dequant()
  AAC: Unswitch loop over window groups in decode_spectrum_and_dequant()
  AAC: Reduce depth of vlc_spectral tables to 2

 libavcodec/aac.c    |  324 ++++++++++++++++++++++++++++++++++++++-------------
 libavcodec/aac.h    |    2 +-
 libavcodec/aactab.c |  161 +++++++++++++++++++++++++
 libavcodec/aactab.h |    2 +
 4 files changed, 408 insertions(+), 81 deletions(-)

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