FFmpeg

Commit Graph

Author	SHA1	Message	Date
Rostislav Pehlivanov	aef5f9ab05	mdct15: remove redundant scale argument to imdct_half The only use of that argument was for Opus downmixing which is very rare and better done after the mdcts. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	7 years ago
Rostislav Pehlivanov	e1120b1c54	mdct15: add assembly optimizations for the 15-point FFT c: 1802 decicycles in fft15,16774635 runs, 2581 skips avx: 865 decicycles in fft15,16776378 runs, 838 skips Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Rostislav Pehlivanov	db788de8ec	mdct15: use existing complex multiplication macros Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Rostislav Pehlivanov	38d7cc22f7	mdct15: fix left shift of a negative value Should fix Chromium issue 704064. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Rostislav Pehlivanov	d2119f624d	imdct15: rename to mdct15 and add a forward transform Handles strides (needed for Opus transients), does pre-reindexing and folding without needing a copy. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Rostislav Pehlivanov	2d208aaabe	imdct15: replace the FFT with a faster PFA FFT algorithm This commit replaces the current inefficient non-power-of-two FFT with a much faster FFT based on the Prime Factor Algorithm. Although it is already much faster than the old algorithm without SIMD, the new algorithm makes use of the already very throughouly SIMD'd power of two FFT, which improves performance even more across all platforms which we have SIMD support for. Most of the work was done by Peter Barfuss, who passed the code to me to implement into the iMDCT and the current codebase. The code for a 5-point and 15-point FFT was derived from the previous implementation, although it was optimized and simplified, which will make its future SIMD easier. The 15-point FFT is currently using 6% of the current overall decoder overhead. The FFT can now easily be used as a forward transform by simply not multiplying the 5-point FFT's imaginary component by -1 (which comes from the fact that changing the complex exponential's angle by -1 also changes the output by that) and by multiplying the "theta" angle of the main exptab by -1. Hence the deliberately left multiplication by -1 at the end. FATE passes, and performance reports on other platforms/CPUs are welcome. Performance comparisons: iMDCT, PFA: 101127 decicycles in speed, 32765 runs, 3 skips iMDCT, Old: 211022 decicycles in speed, 32768 runs, 0 skips Standalone FFT, 300000 transforms of size 960: PFA Old FFT kiss_fft libfftw3f 3.659695s, 15.726912s, 13.300789s, 1.182222s Being only 3x slower than libfftw3f is a big achievement by itself. There appears to be something capping the performance in the iMDCT side of things, possibly during the pre-stage reindexing. However, it is certainly fast enough for now. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Rostislav Pehlivanov	4fdacf4cdb	imdct15: remove the AArch64 assembly Prep work for the next commit, which will add a new FFT algorithm which makes the iMDCT over 3x faster than it is currently (standalone, the FFT is with some framesizes over 10x faster). The new FFT algorithm uses the already thouroughly SIMD'd power of two FFT which already has SIMD for AArch64, so users of that platform will still see an improvement. The previous FFT+SIMD was barely 2.5x faster than the C versions on these platforms. Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>	8 years ago
Diego Biurrun	3d5d46233c	opus: Factor out imdct15 into a standalone component It will be reused by the AAC decoder.	10 years ago
Michael Niedermayer	24222cc1d5	avcodec/opus_imdct: Use av_malloc_array() Signed-off-by: Michael Niedermayer <michaelni@gmx.at>	10 years ago
Janne Grunau	d3f5b94762	aarch64: opus NEON iMDCT and FFT Opus celt decoding 11% faster and the iMDCT over 2.5 times faster on Apple's A7.	11 years ago
Anton Khirnov	b70d7a4ac7	lavc: add a native Opus decoder. Initial implementation by Andrew D'Addesio <modchipv12@gmail.com> during GSoC 2012. Completion by Anton Khirnov <anton@khirnov.net>, sponsored by the Mozilla Corporation. Further contributions by: Christophe Gisquet <christophe.gisquet@gmail.com> Janne Grunau <janne-libav@jannau.net> Luca Barbato <lu_zero@gentoo.org>	11 years ago

5 Commits (a3d3cfa65c01123edf46d22c3fab7ef1bb428b37)