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5085432f8b
Implemented clmul algorithm for aarch64 using PMULL and EOR3 instructions. The logic and structure is same as x86 clmul implementation with slight rearrangement of constants as per PMULL and PMULL2 instructions. Benchmarking in Android (Termux) on a MediaTek Dimensity 9400 SoC: ./tests/checkasm/checkasm --test=crc --bench --runs=12 benchmarking with native FFmpeg timers nop: 0.2 checkasm: SVE 128 bits, using random seed 2502847808 checkasm: bench runs 4096 (1 << 12) CRC: - crc.crc [OK] PMULL: - crc.crc [OK] checkasm: all 10 tests passed crc_8_ATM_c: 26.0 ( 1.00x) crc_8_ATM_pmull_eor3: 0.7 (37.17x) crc_8_EBU_c: 46.4 ( 1.00x) crc_8_EBU_pmull_eor3: 1.5 (31.47x) crc_16_ANSI_c: 36.3 ( 1.00x) crc_16_ANSI_pmull_eor3: 1.1 (31.70x) crc_16_ANSI_LE_c: 90.9 ( 1.00x) crc_16_ANSI_LE_pmull_eor3: 2.8 (32.30x) crc_16_CCITT_c: 118.0 ( 1.00x) crc_16_CCITT_pmull_eor3: 3.7 (32.00x) crc_24_IEEE_c: 1.6 ( 1.00x) crc_24_IEEE_pmull_eor3: 0.1 (12.19x) crc_32_IEEE_c: 45.2 ( 1.00x) crc_32_IEEE_pmull_eor3: 1.4 (31.39x) crc_32_IEEE_LE_c: 49.1 ( 1.00x) crc_32_IEEE_LE_crc: 2.5 (19.51x) crc_32_IEEE_LE_pmull_eor3: 1.5 (32.84x) crc_custom_polynomial_c: 45.3 ( 1.00x) crc_custom_polynomial_pmull_eor3: 1.3 (35.16x)
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.