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Jeongkeun Kim
4ea59d5665
Port lfe_fir0_float and lfe_fir1_float to AArch64 NEON. These polyphase FIR interpolation filters have an x86 SSE/AVX path but no AArch64 equivalent, falling back to scalar C. The inner loop computes two dot products per output pair. Precomputing a reversed LFE sample vector before the inner loop avoids per-iteration shuffle overhead. Benchmarks on AWS Graviton3 (Neoverse V1, c7g.xlarge): lfe_fir0_float: C 5902.0 cycles -> NEON 2135.0 cycles (2.77x) lfe_fir1_float: C 2836.3 cycles -> NEON 1527.8 cycles (1.86x) Measured with: taskset -c 0 ./tests/checkasm/checkasm --test=dcadsp --bench, 3-run average, Ubuntu 22.04 (kernel 6.8.0-1052-aws), perf_event_paranoid=0. Signed-off-by: Jeongkeun Kim <variety0724@gmail.com>
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.