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ce89d974c8
Implement NEON optimization for HEVC dequant at 10-bit depth. For 10-bit: shift = 15 - 10 - log2_size = 5 - log2_size Performance benchmark on Apple M4: ./tests/checkasm/checkasm --test=hevc_dequant --bench hevc_dequant_4x4_10_c: 16.6 ( 1.00x) hevc_dequant_4x4_10_neon: 7.4 ( 2.23x) hevc_dequant_8x8_10_c: 39.7 ( 1.00x) hevc_dequant_8x8_10_neon: 7.5 ( 5.28x) hevc_dequant_16x16_10_c: 168.7 ( 1.00x) hevc_dequant_16x16_10_neon: 10.2 (16.56x) hevc_dequant_32x32_10_c: 1.9 ( 1.00x) hevc_dequant_32x32_10_neon: 1.9 ( 1.01x) Note: 32x32 shift=0 is identity transform (no-op), so NEON has no advantage over C which is also optimized away by the compiler. Signed-off-by: Jun Zhao <barryjzhao@tencent.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.