82c636313d
The mov_text encoder uses an AVBPrint to assemble the subtitles;
yet mov_text subtitles are not pure text; they also have a binary
portion that was mostly handled as follows:
uint32_t size = /* calculation */;
size = AV_RB32(&size);
av_bprint_append_data(bprint, (const char*)&size, 4);
Here AV_RB32() is a no-op on big-endian systems and a LE-BE swap
on little-endian systems, making the output endian-independent.
Yet this is ugly and unclean: On LE systems, the variable size from
the snippet above won't contain the correct value any more. Furthermore,
using this pattern leads to lots of small writes to the AVBPrint.
This commit therefore changes this to using a temporary buffer instead:
uint8_t buf[4];
AV_WB32(buf, /* size calculation */);
av_bprint_append_data(bprint, buf, 4);
This method also allows to use bigger buffers holding more than one
element, saving calls to av_bprint_append_data() and reducing codesize.
Reviewed-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@gmail.com>
FFmpeg README
FFmpeg is a collection of libraries and tools to process multimedia content such as audio, video, subtitles and related metadata.
Libraries
libavcodecprovides implementation of a wider range of codecs.libavformatimplements streaming protocols, container formats and basic I/O access.libavutilincludes hashers, decompressors and miscellaneous utility functions.libavfilterprovides a mean to alter decoded Audio and Video through chain of filters.libavdeviceprovides an abstraction to access capture and playback devices.libswresampleimplements audio mixing and resampling routines.libswscaleimplements 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,ismindexandqt-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.