This is needed because of 32bit float formats (which are difficult to
store in 16bits)

This also fixes undefined behavior found by fate
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

Signed-off-by: Marton Balint <cus@passwd.hu>

PSEUDOPAL pixel formats are not paletted, but carried a palette with the
intention of allowing code to treat unpaletted formats as paletted. The
palette simply mapped the byte values to the resulting RGB values,
making it some sort of LUT for RGB conversion.

It was used for 1 byte formats only: RGB4_BYTE, BGR4_BYTE, RGB8, BGR8,
GRAY8. The first 4 are awfully obscure, used only by some ancient bitmap
formats. The last one, GRAY8, is more common, but its treatment is
grossly incorrect. It considers full range GRAY8 only, so GRAY8 coming
from typical Y video planes was not mapped to the correct RGB values.
This cannot be fixed, because AVFrame.color_range can be freely changed
at runtime, and there is nothing to ensure the pseudo palette is
updated.

Also, nothing actually used the PSEUDOPAL palette data, except xwdenc
(trivially changed in the previous commit). All other code had to treat
it as a special case, just to ignore or to propagate palette data.

In conclusion, this was just a very strange old mechnaism that has no
real justification to exist anymore (although it may have been nice and
useful in the past). Now it's an artifact that makes the API harder to
use: API users who allocate their own pixel data have to be aware that
they need to allocate the palette, or FFmpeg will crash on them in
_some_ situations. On top of this, there was no API to allocate the
pseuo palette outside of av_frame_get_buffer().

This patch not only deprecates AV_PIX_FMT_FLAG_PSEUDOPAL, but also makes
the pseudo palette optional. Nothing accesses it anymore, though if it's
set, it's propagated. It's still allocated and initialized for
compatibility with API users that rely on this feature. But new API
users do not need to allocate it. This was an explicit goal of this
patch.

Most changes replace AV_PIX_FMT_FLAG_PSEUDOPAL with FF_PSEUDOPAL. I
first tried #ifdefing all code, but it was a mess. The FF_PSEUDOPAL
macro reduces the mess, and still allows defining FF_API_PSEUDOPAL to 0.

Passes FATE with FF_API_PSEUDOPAL enabled and disabled. In addition,
FATE passes with FF_API_PSEUDOPAL set to 1, but with allocation
functions manually changed to not allocating a palette.

Don't recommend to use deprecated functions.
Signed-off-by: James Almer <jamrial@gmail.com>

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

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

Add a pixel format flag to identify this family.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

The parameters in the docs are currently swapped.

The new fields can be accessed directly and are more intelligible.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

There is no practical benefit in having this structure elements
bit packed given the size of the structure and its usage.
Change types from uint16_t (packed) to plain int in order to simplify
modifying the structure and accessing its fields.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

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

Deprecated in 10/2012.

Deprecated in 10/2012.

Signed-off-by: Peter Cordes <peter@cordes.ca>

Also make clear that PAL8 can have alpha.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

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

It seems many people do not understand its current documentation
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

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

Also change some comments to multiline.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

Signed-off-by: Lou Logan <lou@lrcd.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

This avoids a dependancy of libavfilter on libavcodec

See Ticket 3592
Fixes Ticket2784
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Signed-off-by: Anton Khirnov <anton@khirnov.net>

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

This will be needed to allow removing the PixFmtInfo table
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Add explanations what the difference between the 2 functions are and
when either should be used.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

Deprecate avcodec_get_chroma_sub_sample.

Make av_pix_fmt_descriptors table static on next major bump.

Making the table public is dangerous, since the caller has no way to
know how large it actually is. It also prevents adding new fields to
AVPixFmtDescriptor without a major bump.