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4af496473a
This new FATE test for the scale2ref filter makes use of the recently added scale2ref-specific variables to maintain the aspect ratio of a test input. Filtergraph explanation: [main] has an AR of 4:3. [ref] has an AR of 16:9. 640 / 4 = 160. So the new width for [main] is 160. 160 / ((320 / 240) * (1 / 1)) = 160 / (4 / 3) = 120. So the new height for [main] is 120. 160 / 120 = 4 / 3 so [main]'s aspect ratio has been maintained while using [ref]'s width as a reference point. [ref] is nullsink'd since it is left unchanged by scale2ref (and so shouldn't need to be tested). If we were to use "iw/4:-1" in place of "iw/4:ow/mdar": 640 / 4 = 160. So the new width for [main] would be 160. 360 / 4 = 90. So the new height for [main] would be 90. 160 / 90 = 16 / 9 so [main] now has the same aspect ratio as [ref] which is probably what you do not want. This is currently the only test for scale2ref. Signed-off-by: Kevin Mark <kmark937@gmail.com> Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
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.
- ffserver is a multimedia streaming server for live broadcasts.
- 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.