The AAC decoder and ADTS-to-ASC BSF both require the header decoder
but not full parsing capabilities.
Originally committed as revision 24217 to svn://svn.ffmpeg.org/ffmpeg/trunk
It created false positives on seeks and where the first frame is STOP or SHORT.
It failed to warn in illegal SHORT->LONG transitions. In general it created
much confusion and many junk bug reports from the users.
Originally committed as revision 24214 to svn://svn.ffmpeg.org/ffmpeg/trunk
Passing an explicit filename to this command is only necessary if the
documentation in the @file block refers to a file different from the
one the block resides in.
Originally committed as revision 22921 to svn://svn.ffmpeg.org/ffmpeg/trunk
A large portion of this code was orignally authored by Robert Swain. The rest
was written by me. Full history is available at:
svn://svn.ffmpeg.org/soc/aac-sbr
http://github.com/aconverse/ffmpeg-heaac/tree/sbr_pub
Originally committed as revision 22316 to svn://svn.ffmpeg.org/ffmpeg/trunk
This results in a 50% speedup on main profile with no increase in binary size.
Originally committed as revision 22196 to svn://svn.ffmpeg.org/ffmpeg/trunk
Due to a shortcoming in the AAC specification, if an all zero buffer is
fed to section data decoding it will never terminate. That means without
a buffer exhaustion check decode_band_types() will consume all input
buffer padding. Worse if a get_bits() implementation that returns zeros
when padding is exhausted is used, the function will never terminate.
The fixes that by added a buffer exhaustion check in the sectioning
decoding loop.
Originally committed as revision 22044 to svn://svn.ffmpeg.org/ffmpeg/trunk
Using the low-level macros directly avoids redundant open/update/close
cycles.
2-3% faster on ARM, PPC, and Core i7.
Originally committed as revision 21224 to svn://svn.ffmpeg.org/ffmpeg/trunk
Simplify cur_band_type, group_len, and coef/offset calculations. This
makes the code easier to read and slightly faster.
Originally committed as revision 21189 to svn://svn.ffmpeg.org/ffmpeg/trunk
The codebooks each consist of small number of values repeated in
groups of 2 or 4. Storing the codebooks as a packed list of 2- or
4-bit indexes into a table reduces their size substantially (from 7.5k
to 1.5k), resulting in less cache pressure.
For the band types with sign bits in the bitstream, storing the number
and position of non-zero codebook values using a few bits avoids
multiple get_bits() calls and floating-point comparisons which gcc
handles miserably.
Some float/int type punning also avoids gcc brain damage.
Overall speedup 20-35% on Cortex-A8, 20% on Core i7.
Originally committed as revision 21188 to svn://svn.ffmpeg.org/ffmpeg/trunk
The maximum length of escape_sequence is 21 bits, so adjust limit in
code to match this.
Up to 10% faster on Cortex-A8.
Originally committed as revision 21153 to svn://svn.ffmpeg.org/ffmpeg/trunk
The maximum length of escape_sequence is 21 bits, so adjust limit in
code to match this. Also fix the comment.
Originally committed as revision 21151 to svn://svn.ffmpeg.org/ffmpeg/trunk
Alex Converse
Måns Rullgård
Diego Biurrun
Cyril Russo
Stefano Sabatini
Reimar Döffinger
Carl Eugen Hoyos
Andreas Öman