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58a2dc3c2ea31da1c73b81ea8162abdb0a00e628
Add NEON implementation using LD3 to load 48 bytes with de-interleaving using which 6 bits are extracted using USHR and SLI to get 4 registers, which is used as a index into lookup table using TBL with 4 registers to translate into the 64-byte output, which is written using ST4 to interleave. Add a checkasm test to validate the input lengths from 0 to 239 bytes to cover all the code paths introduced in the NEON implementation. Refactored the C implementation into a header file so that it can be used from checkasm test without having to duplicate the code there. Observed about 4x speedup by checkasm on A720 core on 1kB input: C: - base64.base64 [OK] NEON: - base64.base64 [OK] checkasm: all 1 tests passed Benchmark results: name nsecs (vs ref) av_base64_encode_c: 1286.9 av_base64_encode_neon: 315.5 ( 4.08x)
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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
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.
Languages
C
88.8%
Assembly
8.4%
Makefile
1.6%
GLSL
0.4%
C++
0.3%
Other
0.3%