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43a8e2da01
This is a ground-up refactor of the existing x86 ops code, using the new uops macros to auto-generate every single kernel instance without guesswork. While I was at it, I also cleaned up the file a bit and made sure we have only a single, consistent way of writing/defining the kernels. This also gets rid of some of the old boilerplate like decl_pattern. Most kernels are trivial ports, but a few deserve attention or note: - SWS_UOP_LINEAR is now generated more efficiently, thanks to the distinction between 0/1/arbitrary components. I also rewrote the code to keep track of whether the output was initialized yet or not, which lets us skip the initial `xorps` and `addps` for the first component. - SWS_UOP_PERMUTE is generated automatically by using some NASM logic to detect permutation cycles and emit the minimal sequence of `mova` instructions. SWS_UOP_COPY, on the other hand, is implemented naively. I originally had a more complex implementation that could handle both, but I decided it really isn't worth the complication just to save 2-3 cycles. - SWS_UOP_SCALE now has a native 8-bit implementation, which is faster than falling back to C code. - SWS_UOP_SWAP_BYTES is no longer compiled as a type-agnostic pshufb, instead we hard-code the shuffle mask - SWS_UOP_DITHER is now much simpler and avoids branching etc. entirely Signed-off-by: Niklas Haas <git@haasn.dev>
FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodecprovides implementation of a wider range of codecs.libavformatimplements streaming protocols, container formats and basic I/O access.libavutilincludes hashers, decompressors and miscellaneous utility functions.libavfilterprovides means to alter decoded audio and video through a directed graph of connected filters.libavdeviceprovides an abstraction to access capture and playback devices.libswresampleimplements audio mixing and resampling routines.libswscaleimplements 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,ismindexandqt-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.