Lynne 5ca40d6d94 lavu/tx: support in-place FFT transforms ... This commit adds support for in-place FFT transforms. Since our internal transforms were all in-place anyway, this only changes the permutation on the input. Unfortunately, research papers were of no help here. All focused on dry hardware implementations, where permutes are free, or on software implementations where binary bloat is of no concern so storing dozen times the transforms for each permutation and version is not considered bad practice. Still, for a pure C implementation, it's only around 28% slower than the multi-megabyte FFTW3 in unaligned mode. Unlike a closed permutation like with PFA, split-radix FFT bit-reversals contain multiple NOPs, multiple simple swaps, and a few chained swaps, so regular single-loop single-state permute loops were not possible. Instead, we filter out parts of the input indices which are redundant. This allows for a single branch, and with some clever AVX512 asm, could possibly be SIMD'd without refactoring. The inplace_idx array is guaranteed to never be larger than the revtab array, and in practice only requires around log2(len) entries. The power-of-two MDCTs can be done in-place as well. And it's possible to eliminate a copy in the compound MDCTs too, however it'll be slower than doing them out of place, and we'd need to dirty the input array.		2021-02-21 17:05:16 +01:00
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dev_community	doc: Add dev_community/community.md for general assembly and main elections process.	2020-10-19 14:35:14 +02:00
doxy	Merge commit '257f00ec1ab06a2a161f535036c6512f3fc8e801'	2016-06-22 11:28:51 +02:00
examples	doc/examples/transcoding: switch to the new encoding API	2020-11-20 15:20:24 +01:00
.gitignore	Merge commit '257f00ec1ab06a2a161f535036c6512f3fc8e801'	2016-06-22 11:28:51 +02:00
APIchanges	lavu/tx: support in-place FFT transforms	2021-02-21 17:05:16 +01:00
authors.texi
bitstream_filters.texi	avcodec/setts_bsf: add sample rate for expressions	2021-02-15 20:52:44 +01:00
bootstrap.min.css
build_system.txt	tools: add a fuzzer tool for bitstream filters	2019-12-05 20:49:15 -03:00
codecs.texi	doc/codecs: add entries for export_side_data	2020-12-20 15:09:28 +05:30
decoders.texi	avcodec/av1dec: add an option to select an operating point	2021-01-04 16:28:29 -03:00
default.css
demuxers.texi	doc/demuxers: update mov section	2020-03-06 11:05:30 +05:30
developer.texi	fftools/ffmpeg: update text requesting samples	2020-06-01 14:39:52 -04:00
devices.texi
doxy-wrapper.sh
Doxyfile	doc: fix spelling errors	2016-10-21 23:58:47 +02:00
encoders.texi	avcodec/libaomenc: add support for setting arbitrary libaom options	2021-02-10 11:52:46 +02:00
errno.txt
faq.texi	doc/faq: update macOS and URLs	2019-02-11 10:13:31 +05:30
fate_config.sh.template	Merge commit '35d1f726eb9fdd376ab900587fb02122b72f2b9a'	2017-05-05 09:27:18 +02:00
fate.texi	doc/fate: Document how to request samples upload access	2019-08-09 01:33:49 +02:00
ffmpeg-bitstream-filters.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-codecs.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-devices.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-filters.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-formats.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-protocols.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-resampler.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-scaler.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg-utils.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
ffmpeg.texi	ffmpeg: add -fpsmax to clamp output framerate	2021-02-05 22:54:18 +05:30
ffmpeg.txt
ffplay.texi	doc: include general in *-all pages.	2020-09-08 14:29:19 +02:00
ffprobe.texi	doc: include general in *-all pages.	2020-09-08 14:29:19 +02:00
ffprobe.xsd	fftools/ffprobe: show closed caption info in the stream dump	2020-05-02 19:14:08 +02:00
fftools-common-opts.texi	doc/fftools-common-opts: document max_alloc	2021-01-23 14:59:47 +05:30
filter_design.txt	doc: update filter_design.txt.	2017-09-12 11:03:51 +02:00
filters.texi	avfilter: add vif filter	2021-02-16 15:00:50 +01:00
formats.texi	avformat: Add max_probe_packets option	2019-11-03 11:52:32 +01:00
general_contents.texi	doc/general_contents: add few more entries	2021-02-07 00:01:12 +01:00
general.texi	doc/general: move contents into a separate file.	2020-09-08 14:29:19 +02:00
git-howto.texi	Merge commit '41ed7ab45fc693f7d7fc35664c0233f4c32d69bb'	2016-06-21 21:55:34 +02:00
indevs.texi	avdevice/decklink_dec: add support for 50/60 fps timecode	2020-12-03 18:32:57 +01:00
issue_tracker.txt	Remove the ffserver program	2018-01-06 18:31:37 +00:00
lexicon	doc: add a lexicon	2017-02-03 15:03:44 +01:00
libav-merge.txt	doc/libav-merge: add a line about the previous skipped merge	2019-02-20 13:51:19 -03:00
libavcodec.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libavdevice.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libavfilter.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libavformat.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libavutil.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libswresample.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
libswscale.texi	Remove the ffserver program	2018-01-06 18:31:37 +00:00
mailing-list-faq.texi	Revert "doc/mailing-list-faq: Mention current problem with GMX"	2020-05-08 13:29:43 +02:00
Makefile	doc: Add mailing list FAQ	2017-10-03 15:25:07 -08:00
metadata.texi	doc/metadata: fix error in timebase description	2018-12-14 12:57:34 +01:00
mips.txt
multithreading.txt	avcodec: deprecate thread_safe_callbacks	2020-11-27 15:46:50 +01:00
muxers.texi	avformat/hlsenc: use AV_OPT_TYPE_DURATION	2021-02-02 20:55:50 +08:00
nut.texi	Merge commit '41ed7ab45fc693f7d7fc35664c0233f4c32d69bb'	2016-06-21 21:55:34 +02:00
optimization.txt	build: Prefer NASM assembler over YASM	2017-06-21 17:00:30 -03:00
outdevs.texi	lavdevice: Add AudioToolbox output device.	2020-06-15 15:09:33 +02:00
patchwork	doc/patchwork: Document the patchwork states	2016-10-26 19:46:00 +02:00
platform.texi	configure: error out on unsupported MSVC versions	2018-05-18 02:22:57 +01:00
print_options.c	Merge commit '2025d3787158ba272a1b8fbc0493fa20dd7a8484'	2017-03-29 15:20:10 +02:00
protocols.texi	doc/protocols: explain tcp listen option description	2021-01-09 17:08:27 +01:00
rate_distortion.txt
resampler.texi	swresample/options: enable linear_interp and exact_rational by default	2017-03-17 00:08:03 +07:00
scaler.texi	doc/swscaler: explain default Lanczos parameter	2019-05-27 21:32:33 +05:30
snow.txt	doc/snow: fix typos	2019-02-10 16:46:56 +01:00
style.min.css
swresample.txt
swscale.txt	cosmetics: Fix spelling mistakes	2016-05-04 18:16:21 +02:00
t2h.init	doc/t2h: use container	2016-10-03 00:16:27 +01:00
t2h.pm	doc/t2h: use container	2016-10-03 00:16:27 +01:00
tablegen.txt
texi2pod.pl	doc/texi2pod: support @float.	2020-09-08 14:29:19 +02:00
texidep.pl
undefined.txt	doc: Add initial documentation explaining undefined behavior and SUINT	2017-07-21 17:37:05 +02:00
utils.texi	doc/utils: document the "s", "ms" and "us" suffixes for durations	2020-06-09 17:55:52 +05:30
writing_filters.txt	doc/writing_filters: Use ff_filter_get_nb_threads() get number of threads	2019-05-22 17:43:41 +08:00