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Rostislav Pehlivanov 44ddee945a aacenc_pred: rework the way prediction is done
This commit completely alters the algorithm of prediction.
The original commit which introduced prediction was completely
incorrect to even remotely care about what the actual coefficients
contain or whether any options were enabled. Not my actual fault.

This commit treats prediction the way the decoder does and expects
to do: like lossy encryption. Everything related to prediction now
happens at the very end but just before quantization and encoding
of coefficients. On the decoder side, prediction happens before
anything has had a chance to even access the coefficients.

Also the original implementation had problems because it actually
touched the band_type of special bands which already had their
scalefactor indices marked and it's a wonder the asserion wasn't
triggered when transmitting those.

Overall, this now drastically increases audio quality and you should
think about enabling it if you don't plan on playing anything encoded
on really old low power ultra-embedded devices since they might not
support decoding of prediction or AAC-Main. Though the specifications
were written ages ago and as times change so do the FLOPS.

Signed-off-by: Rostislav Pehlivanov <atomnuker@gmail.com>
2015-08-29 06:34:08 +01:00
compat
doc doc/examples/filtering_video: better demo ffmpeg filters; demos chaining the filters 2015-08-28 12:53:35 +02:00
libavcodec aacenc_pred: rework the way prediction is done 2015-08-29 06:34:08 +01:00
libavdevice avdevice/lavfi: fix self assignment warning 2015-08-23 20:00:03 +02:00
libavfilter avfilter/vf_dejudder: use the name 's' for the pointer to the private context 2015-08-28 19:05:19 +00:00
libavformat avformat/segment: atomically update list if possible 2015-08-28 00:09:56 +02:00
libavresample
libavutil Merge commit 'e23f84d9652474353d8bbc42787a56ec1991908f' 2015-08-24 10:40:24 +02:00
libpostproc avutil/x86/asm: rename REG_SP to REG_sp 2015-08-22 02:56:53 +02:00
libswresample swresample/dither: use integer arithmetic 2015-08-23 23:19:31 +02:00
libswscale swscale: Silence an unused variable warning 2015-08-25 17:40:06 -07:00
presets
tests checkasm: Fix floating point arguments on 64-bit Windows 2015-08-25 19:34:46 +02:00
tools
.gitattributes
.gitignore
arch.mak
Changelog Changelog: Add VDPAU HEVC to the list 2015-08-28 08:16:39 -07:00
cmdutils_common_opts.h
cmdutils_opencl.c
cmdutils.c
cmdutils.h
common.mak
configure configure: Do not let the webm muxer suggest external libraries. 2015-08-28 06:03:58 +02:00
COPYING.GPLv2
COPYING.GPLv3
COPYING.LGPLv2.1
COPYING.LGPLv3
CREDITS
ffmpeg_dxva2.c
ffmpeg_filter.c
ffmpeg_opt.c Put remaining pieces of CODEC_FLAG_EMU_EDGE under FF_API_EMU_EDGE. 2015-08-28 14:40:59 -04:00
ffmpeg_vdpau.c
ffmpeg_videotoolbox.c
ffmpeg.c ffmpeg: force 128k default audio bitrate if nothing is specified and there is no specific default 2015-08-28 23:07:12 +02:00
ffmpeg.h
ffplay.c Put remaining pieces of CODEC_FLAG_EMU_EDGE under FF_API_EMU_EDGE. 2015-08-28 14:40:59 -04:00
ffprobe.c
ffserver_config.c ffserver: use -b instead of -ab for setting audio bitrate. 2015-08-28 14:59:58 -04:00
ffserver_config.h
ffserver.c
INSTALL.md
library.mak
LICENSE.md
MAINTAINERS
Makefile
README.md
RELEASE
version.sh

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.