Before commit f025b8e110b36c1cdb4fb56c4cd57aeca1767b5b, every frame-threaded decoder used ThreadFrames, even when they did not have any inter-frame dependencies at all. In order to distinguish those decoders that need the AVBuffer for progress communication from those that do not (to avoid the allocation for the latter), the former decoders were marked with the FF_CODEC_CAP_ALLOCATE_PROGRESS internal codec cap. Yet distinguishing these two can be done in a more natural way: Don't use ThreadFrames when not needed and split ff_thread_get_buffer() into a core function that calls the user's get_buffer2 callback and a wrapper around it that also allocates the progress AVBuffer. This has been done in 02220b88fc38ef9dd4f2d519f5d3e4151258b60c and since that commit the ALLOCATE_PROGRESS cap was nearly redundant. The only exception was WebP and VP8. WebP can contain VP8 and uses the VP8 decoder directly (i.e. they share the same AVCodecContext). Both decoders are frame-threaded and VP8 has inter-frame dependencies (in general, not in valid WebP) and therefore the ALLOCATE_PROGRESS cap. In order to avoid allocating progress in case of a frame-threaded WebP decoder the cap and the check for the cap has been kept in place. Yet now the VP8 decoder has been switched to use ProgressFrames and therefore there is just no reason any more for this check and the cap. This commit therefore removes both. Also change the value of FF_CODEC_CAP_USES_PROGRESSFRAMES to leave no gaps. Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
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FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodec
provides implementation of a wider range of codecs.libavformat
implements streaming protocols, container formats and basic I/O access.libavutil
includes hashers, decompressors and miscellaneous utility functions.libavfilter
provides means to alter decoded audio and video through a directed graph of connected filters.libavdevice
provides an abstraction to access capture and playback devices.libswresample
implements audio mixing and resampling routines.libswscale
implements color conversion and scaling routines.
Tools
- ffmpeg is a command line toolbox to manipulate, convert and stream multimedia content.
- ffplay is a minimalistic multimedia player.
- ffprobe is a simple analysis tool to inspect multimedia content.
- Additional small tools such as
aviocat
,ismindex
andqt-faststart
.
Documentation
The offline documentation is available in the doc/ directory.
The online documentation is available in the main website and in the wiki.
Examples
Coding examples are available in the doc/examples directory.
License
FFmpeg codebase is mainly LGPL-licensed with optional components licensed under GPL. Please refer to the LICENSE file for detailed information.
Contributing
Patches should be submitted to the ffmpeg-devel mailing list using
git format-patch
or git send-email
. Github pull requests should be
avoided because they are not part of our review process and will be ignored.
Description
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