Niklas Haas 2a1d9c080f swscale/alphablend: don't overread alpha plane on subsampled odd size
This function overreads the input plane for odd dimensions, because the
chroma plane is always rounded up, which means (xy << subsample) + 1 exceeds
the actual alpha plane size.

To verify:
  valgrind ffmpeg -pix_fmt yuva420p -f lavfi -i color -vf \
  "scale=1x1,format=yuva420p,scale=alphablend=uniform_color,format=yuv420p \
  -vframes 1 -f null -

Fixes: https://trac.ffmpeg.org/ticket/11692
(cherry picked from commit b7946098b1)
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
2026-06-20 17:42:28 +02:00
2026-01-02 20:05:51 +01:00
2026-05-05 02:07:25 +02:00
2025-12-03 20:27:24 +01:00
2022-03-17 18:35:41 -03:00
2026-05-05 02:07:25 +02:00
2025-12-03 20:27:24 +01:00
2023-03-01 21:59:10 +01:00
2024-12-07 02:37:17 -05:00
2026-05-05 02:07:25 +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.

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