• Mattias Wadman's avatar
    libavformat/flacdec: Workaround for truncated metadata picture size · af97c986
    Mattias Wadman authored
    Some flac muxers write truncated metadata picture size if the picture
    data do not fit in 24 bits. Detect this by truncting the size found inside
    the picture block and if it matches the block size use it and read rest
    of picture data.
    
    This workaround is only for flac files and not ogg files with flac
    METADATA_BLOCK_PICTURE comments and it can be disabled with strict level
    above normal. Currently there is a 500MB limit on truncate size to protect
    from large memory allocations.
    
    The truncation bug in lavf flacenc was fixed in e447a4d1
    but based on existing broken files other unknown flac muxers seems to truncate also.
    Before the fix a broken flac file for reproduction could be generated with:
    ffmpeg -f lavfi -i sine -f lavfi -i color=red:size=2400x2400 -map 0:0 -map 1:0 -c:v:0 bmp -disposition:1 attached_pic -t 1 test.flac
    
    Fixes ticket 6333
    Signed-off-by: 's avatarAnton Khirnov <anton@khirnov.net>
    af97c986
flacdec.c 12 KB