swscale: correctly pad destination buffer in rgb conversion

Bug-Id: 772
CC: libav-stable@libav.org
Found-By: Justin Ruggles <justin.ruggles@gmail.com>
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
pixdesc: Support pixelformat aliases

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
avutil: add alias names for gray 8/16 colour spaces
avutil: rename AV_PIX_FMT_Y400A to AV_PIX_FMT_YA8

The rationale is that you have a packed format in form
<greyscale sample> <alpha sample> <greyscale sample> <alpha sample>
and shortening greyscale to 'G' might make one thing about Greenscale instead.
An alias pixel format and color space name are provided for compatibility.
avutil: add AV_PIX_FMT_YA16 pixel format
swscale: support AV_PIX_FMT_YA16 as input

Based on a long debug session with Kostya.
png: disable broken MMX/SIMD code for bpp <= 2

The decoder was producing different results when ASM was disabled.
Based on a long debug session with Kostya.
png: support reading gray+alpha at 16 bits
tiff: support reading gray+alpha at 16 bits
tiff: support reading gray+alpha at 8 bits

Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
fate: png-suite

Every supported format is converted to RGB.
x86: hevc_deblock: remove unnecessary masking

The unpacks/shuffles later on makes it unnecessary.

Before:
1508 decicycles in h, 2096759 runs, 393 skips
2512 decicycles in v, 2095422 runs, 1730 skips

After:
1477 decicycles in h, 2096745 runs, 407 skips
2484 decicycles in v, 2095297 runs, 1855 skips

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avformat/util: change av_find_default_stream_index() to use a score based system

Disfavor video streams with unknown resolution and no packets
Fixes seeking in audio-only-speex.flv

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
avcodec: Suppress deprecation warnings from DTG code scheduled for removal
fate: Only generate tests/pixfmts.mak if some pixfmts fate test is run
Merge commit '5420099cab1e915b191cceccec4364f54cec6e52'

* commit '5420099cab1e915b191cceccec4364f54cec6e52':
  swscale: correctly pad destination buffer in rgb conversion

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'd2962e9f89cca6ff40f0c9d5ffc9c4397b8b1b26'

* commit 'd2962e9f89cca6ff40f0c9d5ffc9c4397b8b1b26':
  pixdesc: Support pixelformat aliases

Conflicts:
	doc/APIchanges
	libavutil/pixdesc.c
	libavutil/version.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'e0d73fda361729d207e51fa2afd8ba6102e58d98'

* commit 'e0d73fda361729d207e51fa2afd8ba6102e58d98':
  avutil: add alias names for gray 8/16 colour spaces

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'e96c3b81cadd0ba84d43b1f3a54980df3785d9a5'

* commit 'e96c3b81cadd0ba84d43b1f3a54980df3785d9a5':
  avutil: rename AV_PIX_FMT_Y400A to AV_PIX_FMT_YA8

Conflicts:
	libavcodec/libopenjpegdec.c
	libavcodec/libopenjpegenc.c
	libavcodec/raw.c
	libavutil/pixdesc.c
	libavutil/pixfmt.h
	libavutil/version.h
	libswscale/swscale_internal.h
	libswscale/swscale_unscaled.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>
Merge commit 'e9abafca278f87e1ecc6d50091d99b73ff63c9a6'

* commit 'e9abafca278f87e1ecc6d50091d99b73ff63c9a6':
  avutil: add AV_PIX_FMT_YA16 pixel format

Conflicts:
	libavutil/pixdesc.c
	libavutil/pixfmt.h
	libavutil/version.h

Merged-by: Michael Niedermayer <michaelni@gmx.at>