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4bf82ad8df
This partially addresses a a performance regression otherwise introduced by f37b9a3f, which matters especially for 8-bit content where the default threshold value rounds down to an offset of 0. The numbers are still slower than before because the scalar tail handling code is slower by ~200 cycles, since we benchmark across an unaligned width. checkasm: - CPU: AMD Ryzen 9 9950X3D 16-Core Processor (00B40F40) - Timing source: x86 (rdtsc) - Bench duration: 100000 µs per function (460518890 cycles) - Random seed: 2935750295 Benchmark results: name cycles (vs ref) detect_alpha_8_full_c: 7877.4 detect_alpha_8_full_avx2: 1063.4 ( 7.41x) detect_alpha_8_full_avx512icl: 872.1 ( 9.03x) detect_alpha_8_full_off_c: 7890.3 detect_alpha_8_full_off_avx2: 1085.5 ( 7.27x) detect_alpha_8_full_off_avx512icl: 873.0 ( 9.04x) detect_alpha_16_full_c: 3700.9 detect_alpha_16_full_avx2: 797.7 ( 4.64x) detect_alpha_16_full_avx512icl: 612.1 ( 6.05x) detect_alpha_16_full_off_c: 3701.8 detect_alpha_16_full_off_avx2: 801.2 ( 4.62x) detect_alpha_16_full_off_avx512icl: 684.8 ( 5.41x) Sponsored-by: nxtedition AB 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.