ami_stuff <[email protected]> added the comment: Just for information how much a little asm optimization can speed-up a decoder:
ffmpegGCC4org - original FFmpeg compiled with GCC 4.4 ffmpegGCC4asm - asm optimized MUL64/MULH etc. (integer version I posted some time ago) ffmpegGCC4fas - asm optimized MUL64/MULH etc. (floating-point version, the result is not the same, because of "off by one" error with rounding [round toward zero]) mulh.mp3 file is 1 min. long all tests done on 68...@75mhz >cputime ffmpegGCC4org -i mulh.mp3 out.wav Real 00:02:39.427 >cputime ffmpegGCC4asm -i mulh.mp3 out.wav Real 00:01:29.050 >cputime ffmpegGCC4fasm -i mulh.mp3 out.wav Real 00:00:56.658 ---------- title: FFmpeg's MPEG audio decoder is slower than MAD on some systems -> FFmpeg's MPEG audio decoder is slower than MAD on systems without hardware 32x32=>64 _____________________________________________________ FFmpeg issue tracker <[email protected]> <https://roundup.ffmpeg.org/roundup/ffmpeg/issue1051> _____________________________________________________
