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Devin Heitmueller 2b0e794ffc avfilter/ccfifo: Properly handle CEA-708 captions through framerate conversion
When transcoding video that contains 708 closed captions, the
caption data is tied to the frames as side data.  Simply dropping
or adding frames to change the framerate will result in loss of
data, so the caption data needs to be preserved and reformatted.

For example, without this patch converting 720p59 to 1080i59
would result in loss of 50% of the caption bytes, resulting in
garbled 608 captions and 708 probably wouldn't render at all.
Further, the frames that are there will have an illegal
cc_count for the target framerate, so some decoders may ignore
the packets entirely.

Extract the 608 and 708 tuples and insert them onto queues.  Then
after dropping/adding frames, re-write the tuples back into the
resulting frames at the appropriate rate given the target
framerate.  This includes both having the correct cc_count as
well as clocking out the 608 pairs at the appropriate rate.

Thanks to Lance Wang <lance.lmwang@gmail.com>, Anton
Khirnov <anton@khirnov.net>, and Michael Niedermayer <michael@niedermayer.cc>
for providing review/feedback.

Signed-off-by: Devin Heitmueller <dheitmueller@ltnglobal.com>
Signed-off-by: Limin Wang <lance.lmwang@gmail.com>
2023-05-11 22:06:20 +08:00
compat compat: Use '-' instead of '/' for rc.exe options 2023-02-13 13:49:40 +02:00
doc doc/filters/crop: drop unmatched quote in example 2023-05-11 15:54:15 +05:30
ffbuild configure: probe RISC-V Vector extension 2022-09-27 13:19:52 +02:00
fftools fftools/ffprobe: print exported stream AVOptions 2023-05-08 11:04:37 -03:00
libavcodec libavcodec/libsvtav1: Allow -1 for preset option 2023-05-11 10:59:33 -03:00
libavdevice avdevice/lavfi: check that pointer is set 2023-05-10 12:55:22 +02:00
libavfilter avfilter/ccfifo: Properly handle CEA-708 captions through framerate conversion 2023-05-11 22:06:20 +08:00
libavformat lavf/demux: export codec-level framerate in avformat_find_stream_info() 2023-05-07 15:47:25 +02:00
libavutil avutil/version: bump minor after recent changes 2023-05-04 19:20:06 -03:00
libpostproc version.h: Bump minor post 6.0 branch 2023-02-19 18:37:36 +01:00
libswresample swresample/swresample: add a used channel layout option using the new API 2023-02-19 18:28:45 -03:00
libswscale version.h: Bump minor post 6.0 branch 2023-02-19 18:37:36 +01:00
presets
tests fftools/ffprobe: print exported stream AVOptions 2023-05-08 11:04:37 -03:00
tools tools/target_dec_fuzzer: Adjust threshold for rka 2023-05-01 00:48:32 +02:00
.gitattributes
.gitignore gitignore: add config_components.h 2022-03-17 18:35:41 -03:00
.mailmap mailmap: stop git lying about who I commit things as 2022-11-04 19:37:46 +01:00
.travis.yml
Changelog avfilter: add zoneplate video test source 2023-05-09 08:48:44 +02:00
configure lavu/hwcontext_vaapi: Add Windows/VAAPI support with vaGetDisplayWin32 2023-04-24 13:24:41 +08:00
CONTRIBUTING.md
COPYING.GPLv2
COPYING.GPLv3
COPYING.LGPLv2.1
COPYING.LGPLv3
CREDITS Use https for repository links 2023-03-01 21:59:10 +01:00
INSTALL.md
LICENSE.md
MAINTAINERS MAINTAINERS: add vanitous self to maintain RISC-V 2023-05-05 11:54:34 -03:00
Makefile tools: add an AV_CODEC_CAP_ENCODER_RECON_FRAME test tool 2023-03-28 13:00:42 +02:00
README.md
RELEASE RELEASE: update after 5.1 branch 2022-07-13 00:31:42 +02:00

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 means to alter decoded audio and video through a directed graph of connected 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.
  • 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.

Contributing

Patches should be submitted to the ffmpeg-devel mailing list using git format-patch or git send-email. Github pull requests should be avoided because they are not part of our review process and will be ignored.