ac3dec: Allow asymmetric application of DRC when drc_scale > 1

Amplification of quiet sounds is enhanced.
Inspired by gbooker's A52Decoder.
doc: add decoders.texi

Only documents ac3 decoder options at this point.
doc: document correct option to list encoders
Add rangecoder to the sonic dependencies in configure.

Fixes compilation with --disable-everything --enable-decoder=sonic
and --disable-everything --enable-encoder=sonic.
Merge commit '23d461fe8714a20ee5e6929f22c61512fdda568e'

* commit '23d461fe8714a20ee5e6929f22c61512fdda568e':
  ac3dec: Allow asymmetric application of DRC when drc_scale > 1

Conflicts:
	libavcodec/ac3dec.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'a17ab0e46a9fec7c31cc1be363828184c6ecebf7'

* commit 'a17ab0e46a9fec7c31cc1be363828184c6ecebf7':
  doc: add decoders.texi

Conflicts:
	doc/decoders.texi
	doc/ffmpeg.texi
	doc/ffplay.texi

See: 5e45f03420945dfeaf66729f5d022e5c15ff5723
Merged-by: Michael Niedermayer <michaelni@gmx.at>
x86: videodsp: Properly mark sse2 instructions in emulated_edge_mc as such.

Should fix crashes or corrupt output on pre-SSE2 CPUs when they were
using SSE2-code (e.g. AMD Athlon XP 2400+ or Intel Pentium III) in
hfix or hvar single-edge (left/right) extension functions.

Signed-off-by: Janne Grunau <janne-libav@jannau.net>
x86: videodsp: Fix a bug in a %if statement where we used '%%' instead of '&&'.

Signed-off-by: Janne Grunau <janne-libav@jannau.net>
Merge remote-tracking branch 'qatar/master'

* qatar/master:
  doc: document correct option to list encoders

Conflicts:
	doc/encoders.texi

Merged-by: Michael Niedermayer <michaelni@gmx.at>
x86/vp9lpf: add ff_vp9_loop_filter_h_{48,84}_16_{sse2,ssse3,avx}().

5.40s → 5.30s overall decode time with -threads 1 on ped1080p.webm
(i7 920, ssse3)
ffmpeg: also count data streams bytes

Fixes wrong error message about empty output file

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Changelog: add entries relating to metadata_header_padding

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
doc/APIchanges: apply minor formatting fixes
ffmpeg: print data size too in statistic

Reviewed-by: Stefano Sabatini <stefasab@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/hdsenc: check mkdir() return code

This also returns failure if the mkdir failure is not due to an already existing
path.

Fixed CID1135749

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
doc/examples/decoding_encoding: Check all av_samples_get_buffer_size() returns

Fixed CID1135755
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
atrac3plus: Make initialization dependant on channel count rather than channel map

Makes it easier to recreate an AVCodecContext for ATRAC3+ decoding,
which is needed in multimedia frameworks, as well as in general cases
where demuxing and decoding are separate entities.
lavf: include 60 fps in guessed standard frame rates

Due to what looks like an off-by-one error 60 * 12 * 1001 / 12 * 1001
is not tested as standard frame rate in avformat_find_stream_info().
xvid: switch to xvid mmx idct as soon as possible

The idct implementation cannot be changed after the quantization matrices
are read since it use a different permutaion.

Bug-Id: videolan/7411
fate: add xvid test for custom matrices

Test sample is made from the sample in Bug-Id: videolan/7411