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.
The scale2ref filter will now maintain the DAR of the main input and
not the DAR of the reference input. This previous behavior was deemed
counterintuitive for most (all?) use-cases.
Before:
scale2ref=iw/4:ow/mdar
in w:320 h:240 fmt:rgb24 sar:1/1
ref w:640 h:360 fmt:rgb24 sar:1/1
out w:160 h:120 fmt:rgb24 sar:4/3 flags:0x2
SAR: ((120 * 640) / (160 * 360)) * (1 / 1) = 4 / 3
DAR: (160 / 120) * (4 / 3) = 16 / 9
(main out now same DAR as ref)
Now:
scale2ref=iw/4:ow/mdar
in w:320 h:240 fmt:rgb24 sar:1/1
ref w:640 h:360 fmt:rgb24 sar:1/1
out w:160 h:120 fmt:rgb24 sar:1/1 flags:0x2
SAR: ((120 * 320) / (160 * 240)) * (1 / 1) = 1 / 1
DAR: (160 / 120) * (1 / 1) = 4 / 3
(main out same DAR as main in)
The scale2ref FATE test has also been updated.
Signed-off-by: Kevin Mark <kmark937@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Implements support for height/width expressions in vf_scale_vaapi,
by refactoring common code into a new libavfilter/scale.c
Signed-off-by: Mark Thompson <sw@jkqxz.net>
Currently scale filter accepts expressions in its width and height
parameters but evaluates them only once at init and replaces them with
their actual values. Later on, if any parameter of incoming frames
changes - ie those were used in the original size expressions - then
they new values will not have any affect for width and heigth values.
They remain the same. This patch makes possible that width and height
expressions be evaluated frame-by-frame basis if width/height/sar/format
properties of incoming frame would change. To retain the current
behaviour and not to break any earlier app, a new config parameter has
been introduced. Its name is "eval" and it has two distinct values:
"init" and "frame". The default value is "init".
This feature is very usefull in case of DVBT mpeg-ts streams where SAR
may change time-by-time from 4/3 to 16/9 and vica-versa and the size
remains the same and you want to create a variable sized output with 1/1
SAR.
Signed-off-by: Bela Bodecs <bodecsb@vivanet.hu>
Reviewed-by: Paul B Mahol <onemda@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Prevents that following scalers in the filter chain will do unintentional color range conversions.
Fixes Ticket #5096
Signed-off-by: Thomas Mundt <loudmax@yahoo.de>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Many of the functions from avfilter/formats can return errors, usually AVERROR(ENOMEM).
This propagates the return values.
All of these were found by using av_warn_unused_result, demonstrating its utility.
Tested with FATE. I am least sure of the changes to avfilter/filtergraph,
since I don't know what/how reduce_format is intended to behave and how it should
react to errors.
Fixes: CID 1325680, 1325679, 1325678.
Reviewed-by: Michael Niedermayer <michael@niedermayer.cc>
Previous version Reviewed-by: Nicolas George <george@nsup.org>
Previous version Reviewed-by: Clément Bœsch <u@pkh.me>
Signed-off-by: Ganesh Ajjanagadde <gajjanagadde@gmail.com>
For yuv420p, the chroma position is unilaterally overriden, even
if ffmpeg's command-line explicitly set it. To fix this, override
only if the value is the default one.
Regression since 1515bfb3.
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* commit 'b1abd2aaf91be249f24cb74db9c205d9e4ca9da6':
vf_scale: Add an option to pass the scaler params
Merged-by: Hendrik Leppkes <h.leppkes@gmail.com>
This filter can be used to scale one stream to match another or based on
another, useful to scale subtitles or other things to be overlayed
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
* commit '862f33c10ea38ea49fa4188725df5e5246dbd1d8':
vf_scale: use the pixfmt descriptor API
Conflicts:
libavfilter/vf_scale.c
Merged-by: Michael Niedermayer <michaelni@gmx.at>
Avoid using AV_PIX_FMT_NB, since that hardcodes the number of pixel
formats into lavfi and will break when a shared lavu is updated, adding
new pixel formats.
Before, it just returned width/height. Correct is width/height*sar.
That way it is consistent with DAR as in probe output and setdar.
Signed-off-by: Rudolf Polzer <divverent@xonotic.org>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
