FFmpeg git repo
Go to file
Rostislav Pehlivanov 033e58941e aaccoder: rewrite PNS implementation
This commit rewrites the PNS implementation and significantly
improves sonic quality.

The previous implementation marked an incredibly big amount
of SFBs to predict when there was no need for this and this
resulted in quite a large amount of artifacts. Also the
quantization was incorrect (av_clip(4+log2f(...))) which
led to 3x the intensity for PNS values leading to even more
artifacts.

This commit rewrites the PNS search function and introduces
a major change: the PNS values are synthesized and are compared
to the current coefficients in addition to passing through
the revised checks to see whether PNS can be used.

This decreases distortions and makes the current PNS implementation
mainly focused on replacing any low-power non-zero bands as well
as adding any zeroed bands back.

The current encoder's performance is enough (especially with
IS) so PNS isn't really required except to fill in the occasional
few bands as well as extend any zeroed high frequency, so this
combination which is already enabled by default works
to get as much quality as it can within the bits allowed.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-09-06 15:30:26 +01:00
compat
doc avfilter/sine: support expression in the number of output samples 2015-09-06 15:28:21 +02:00
libavcodec aaccoder: rewrite PNS implementation 2015-09-06 15:30:26 +01:00
libavdevice Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
libavfilter avfilter/sine: support expression in the number of output samples 2015-09-06 15:28:21 +02:00
libavformat avformat/samidec: do not include trailing sami footer in the last packet 2015-09-06 13:09:02 +02:00
libavresample Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
libavutil Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
libpostproc Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
libswresample Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
libswscale Merge commit 'e88103a7f92cf27a2868b50acc8a9912f6088249' 2015-09-05 21:35:46 +02:00
presets
tests avcodec/samidec: use ff_htmlmarkup_to_ass() 2015-09-06 13:29:28 +02:00
tools
.gitattributes
.gitignore
COPYING.GPLv2
COPYING.GPLv3
COPYING.LGPLv2.1
COPYING.LGPLv3
CREDITS
Changelog Changelog: add 2.8 2015-09-06 15:59:40 +02:00
INSTALL.md
LICENSE.md
MAINTAINERS
Makefile
README.md
RELEASE
arch.mak
cmdutils.c
cmdutils.h
cmdutils_common_opts.h
cmdutils_opencl.c
common.mak
configure configure: Remove reference to no longer existing avcodec_encode_video() 2015-09-05 22:36:19 +02:00
ffmpeg.c Remove left-over FF_API_DESTRUCT_PACKET cruft 2015-09-05 16:51:53 +02:00
ffmpeg.h
ffmpeg_dxva2.c
ffmpeg_filter.c
ffmpeg_opt.c ffmpeg: Improve help text for -target. 2015-09-02 14:32:06 +02:00
ffmpeg_vdpau.c
ffmpeg_videotoolbox.c
ffplay.c Remove left-over FF_API_AVFILTERBUFFER cruft 2015-09-05 16:27:19 +02:00
ffprobe.c
ffserver.c
ffserver_config.c
ffserver_config.h
library.mak
version.sh

README.md

FFmpeg README

FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.

Libraries

  • libavcodec provides implementation of a wider range of codecs.
  • libavformat implements streaming protocols, container formats and basic I/O access.
  • libavutil includes hashers, decompressors and miscellaneous utility functions.
  • libavfilter provides a mean to alter decoded Audio and Video through chain of filters.
  • libavdevice provides an abstraction to access capture and playback devices.
  • libswresample implements audio mixing and resampling routines.
  • libswscale implements 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.
  • ffserver is a multimedia streaming server for live broadcasts.
  • Additional small tools such as aviocat, ismindex and qt-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.