FFmpeg

Commit Graph

Author	SHA1	Message	Date
Clément Bœsch	7c1a002c78	subtitles: introduce ASS codec id and use it. Currently, we have a AV_CODEC_ID_SSA, which matches the way the ASS/SSA markup is muxed in a standalone .ass/.ssa file. This means the AVPacket data starts with a "Dialogue:" string, followed by a timing information (start and end of the event as string) and a trailing CRLF after each line. One packet can contain several lines. We'll refer to this layout as "SSA" or "SSA lines". In matroska, this markup is not stored as such: it has no "Dialogue:" prefix, it contains a ReadOrder field, the timing information is not in the payload, and it doesn't contain the trailing CRLF. See [1] for more info. We'll refer to this layout as "ASS". Since we have only one common codec for both formats, the matroska demuxer is constructing an AVPacket following the "SSA lines" format. This causes several problems, so it was decided to change this into clean ASS packets. Some insight about what is changed or unchanged in this commit: CODECS ------ - the decoding process still writes "SSA lines" markup inside the ass fields of the subtitles rectangles (sub->rects[n]->ass), which is still the current common way of representing decoded subtitles markup. It is meant to change later. - new ASS codec id: AV_CODEC_ID_ASS (which is different from the legacy AV_CODEC_ID_SSA) - lavc/assdec: the "ass" decoder is renamed into "ssa" (instead of "ass") for consistency with the codec id and allows to add a real ass decoder. This ass decoder receives clean ASS lines (so it starts with a ReadOrder, is followed by the Layer, etc). We make sure this is decoded properly in a new ass-line rectangle of the decoded subtitles (the ssa decoder OTOH is doing a simple straightforward copy). Using the packet timing instead of data string makes sure the ass-line now contains the appropriate timing. - lavc/assenc: just like the ass decoder, the "ssa" encoder is renamed into "ssa" (instead of "ass") for consistency with the codec id, and allows to add a real "ass" encoder. One important thing about this encoder is that it only supports one ass rectangle: we could have put several dialogue events in the AVPacket (separated by a \0 for instance) but this would have cause trouble for the muxer which needs not only the start time, but also the duration: typically, you have merged events with the same start time (stored in the AVPacket->pts) but a different duration. At the moment, only the matroska do the merge with the SSA-line codec. We will need to make sure all the decoders in the future can't add more than one rectangle (and only one Dialogue line in it obviously). FORMATS ------- - lavf/assenc: the .ass/.ssa muxer can take both SSA and ASS packets. In the case of ASS packets as input, it adds the timing based on the AVPacket pts and duration, and mux it with "Dialogue:", trailing CRLF, etc. - lavf/assdec: unchanged; it currently still only outputs SSA-lines packets. - lavf/mkv: the demuxer can now output ASS packets without the need of any "SSA-lines" reconstruction hack. It will become the default at next libavformat bump, and the SSA support will be dropped from the demuxer. The muxer can take ASS packets since it's muxed normally, and still supports the old SSA packets. All the SSA support and hacks in Matroska code will be dropped at next lavf bump. [1]: http://www.matroska.org/technical/specs/subtitles/ssa.html	12 years ago
Clément Bœsch	8de9bb6e5e	lavf: remove some flushing in write_packet muxers callbacks. Since `4f112a8e3`, this is not necessary anymore. Also, it allows to actually disable the flushing.	12 years ago
Clément Bœsch	3704804c8f	lavf/assenc: add non strict ts flag. ASS can have several events at the same time.	12 years ago
Anton Khirnov	3b4bb19e63	lavf: flush the output AVIOContext in av_write_trailer(). This is consistent with stdio and is what we want to do in all cases. Fixes a bug in the voc muxer which didn't flush in write_trailer() previously. This is the cause of the change in the test results.	12 years ago
Anton Khirnov	36ef5369ee	Replace all CODEC_ID_* with AV_CODEC_ID_*	12 years ago
Diego Biurrun	0177b7d23a	Improve descriptiveness of a number of codec and container long names	12 years ago
Diego Biurrun	6774247a9d	avformat: Drop pointless "format" from container long names	12 years ago
Mans Rullgard	2912e87a6c	Replace FFmpeg with Libav in licence headers Signed-off-by: Mans Rullgard <mans@mansr.com>	14 years ago
Anton Khirnov	b7f2fdde74	avio: rename put_flush_packet -> avio_flush Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>	14 years ago
Anton Khirnov	e9eb8d0bce	avio: avio: avio_ prefixes for put_* functions In the name of consistency: put_byte -> avio_w8 put_<type> -> avio_w<type> put_buffer -> avio_write put_nbyte will be made private put_tag will be merged with avio_put_str Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com> (cherry picked from commit `77eb5504d3`)	14 years ago
Anton Khirnov	77eb5504d3	avio: avio: avio_ prefixes for put_* functions In the name of consistency: put_byte -> avio_w8 put_<type> -> avio_w<type> put_buffer -> avio_write put_nbyte will be made private put_tag will be merged with avio_put_str Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>	14 years ago
Diego Elio Pettenò	66355be3c3	Prefix all _demuxer, _muxer, _protocol from libavformat and libavdevice. This also lists the objects from those two libraries as internal (by adding the ff_ prefix) so that they can then be hidden via linker scripts. (cherry picked from commit `c6610a216e`)	14 years ago
Diego Elio Pettenò	c6610a216e	Prefix all _demuxer, _muxer, _protocol from libavformat and libavdevice. This also lists the objects from those two libraries as internal (by adding the ff_ prefix) so that they can then be hidden via linker scripts.	14 years ago
Aurelien Jacobs	5bdbf64cf3	set default subtitle_codec for ass muxer Originally committed as revision 25870 to svn://svn.ffmpeg.org/ffmpeg/trunk	14 years ago
Aurelien Jacobs	908dc2a0b8	cosmetic: alignment Originally committed as revision 25869 to svn://svn.ffmpeg.org/ffmpeg/trunk	14 years ago
Aurelien Jacobs	87d69d3232	use designated initializer in ASS (de)muxer Originally committed as revision 25868 to svn://svn.ffmpeg.org/ffmpeg/trunk	14 years ago
Aurelien Jacobs	7b53f463b4	add mime-type for ASS muxer Originally committed as revision 24502 to svn://svn.ffmpeg.org/ffmpeg/trunk	15 years ago
Aurelien Jacobs	5c7ceef654	improve long_name for ass (de)muxer Originally committed as revision 24084 to svn://svn.ffmpeg.org/ffmpeg/trunk	15 years ago
Michael Niedermayer	88caf34510	ASS/SSA muxer. Originally committed as revision 15430 to svn://svn.ffmpeg.org/ffmpeg/trunk	16 years ago

21 Commits (78d2d1e0270cfbd38022f63f477381ed4294d22c)