The reason why the generic av_image_copy_uc_from() doesn't really
fit in the case for Vulkan is because some planes may be copied via
other methods (such as mapping GPU memory), and if they don't satisfy
the strict alignment requirements, a gpu image->gpu buffer->cpu ram
copy is performed.
We need this for hwcontext_vulkan, and I think this will also be
useful to API users like libplacebo who would rather not write
a custom SIMD memcpy.
This utility helps avoid undefined behavior when doing things like
checking how much memory we need to allocate for an image before we have
allocated a buffer.
Signed-off-by: Brian Kim <bkkim@google.com>
Signed-off-by: James Almer <jamrial@gmail.com>
Black isn't always just memset(ptr, 0, size). Limited YUV in particular
requires relatively non-obvious values, and filling a frame with
repeating 0 bytes is disallowed in some contexts. With component sizes
larger than 8 or packed YUV, this can become relatively complicated. So
having a generic function for this seems helpful.
In order to handle the complex cases in a generic way without destroying
performance, this code attempts to compute a black pixel, and then uses
that value to clear the image data quickly by using a function like
memset.
Common cases like yuv410p10 or rgba can't be handled with a simple
memset, so there is some code to fill memory with 2/4/8 byte patterns.
For the remaining cases, a generic slow fallback is used.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Merged from Libav commit 45df7adc1d.
Black isn't always just memset(ptr, 0, size). Limited YUV in particular
requires relatively non-obvious values, and filling a frame with
repeating 0 bytes is disallowed in some contexts. With component sizes
larger than 8 or packed YUV, this can become relatively complicated. So
having a generic function for this seems helpful.
In order to handle the complex cases in a generic way without destroying
performance, this code attempts to compute a black pixel, and then uses
that value to clear the image data quickly by using a function like
memset.
Common cases like yuv410p10 or rgba can't be handled with a simple
memset, so there is some code to fill memory with 2/4/8 byte patterns.
For the remaining cases, a generic slow fallback is used.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Move the lavc/imgconvert functions and rename them as follows:
avpicture_get_size -> av_image_get_buffer_size()
avpicture_fill -> av_image_fill_arrays()
avpicture_layout -> av_image_copy_to_buffer()
The new functions have an align parameter, which allows to define the
linesize alignment assumed in the buffer (which is set or read).
The names of the functions are consistent with the lavu/samples API
(av_samples_get_buffer_size(), av_samples_fill_arrays()).
A redundant check has been dropped from av_image_fill_arrays().
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>
Move the lavc/imgconvert functions and rename them as follows:
avpicture_get_size -> av_image_get_buffer_size()
avpicture_fill -> av_image_fill_arrays()
avpicture_layout -> av_image_copy_to_buffer()
The new functions have an align parameter, which allows to define the
linesize alignment assumed in the buffer (which is set or read).
The names of the functions are consistent with the lavu/samples API
(av_samples_get_buffer_size(), av_samples_fill_arrays()).
It is pretty hopeless that other considerable projects will adopt
libavutil alone in other projects. Projects that need small footprint
are better off with more specialized libraries such as gnulib or rather
just copy the necessary parts that they need. With this in mind, nobody
is helped by having libavutil and libavcore split. In order to ease
maintenance inside and around FFmpeg and to reduce confusion where to
put common code, avcore's functionality is merged (back) to avutil.
Signed-off-by: Reinhard Tartler <siretart@tauware.de>
av_image_copy(), more consistent with the rest of the API and more
semantically correct.
Originally committed as revision 25070 to svn://svn.ffmpeg.org/ffmpeg/trunk
grepping and somewhat more consistent with the scheme adopted by other
FFmpeg modules API.
Originally committed as revision 25057 to svn://svn.ffmpeg.org/ffmpeg/trunk
The plural form is preferred as it is more consistent with the other functions:
av_fill_image_linesizes()
av_fill_image_pointers()
and looks semantically more correct as it fills an array of elements.
Originally committed as revision 24851 to svn://svn.ffmpeg.org/ffmpeg/trunk
ff_get_plane_bytewidth().
The new implementation is more generic, more compact and more correct.
Originally committed as revision 24786 to svn://svn.ffmpeg.org/ffmpeg/trunk
libavcodec/imgconvert.c and make them public in libavcore/imgutils.h,
with the names av_fill_image_linesizes() and av_fill_image_pointers().
Originally committed as revision 24583 to svn://svn.ffmpeg.org/ffmpeg/trunk
Lynne
Brian Kim
wm4
Vittorio Giovara
Michael Niedermayer
Diego Biurrun
Anton Khirnov
Martin Storsjö
Stefano Sabatini
Justin Ruggles
Luca Barbato
Mans Rullgard
Reinhard Tartler
Stefano Sabatini
Ramiro Polla