[MPlayer-dev-eng] [PATCH] MJPEG patch of APP0/COM skip

[John Witford]

Not all JPEG segments necessarily escape marker values.
Therefore it is wrong to just ignore an unwanted marker
and depend on a generic marker search to skip over the
unwanted segment contents.

This is particularly important for the APP0 segment
because it can include a wide variety of data.
For example, an APP0 "AVI1" segment might contain
the length of the image (EOI-SOS) and therefore might
contain an unescaped marker byte.

The following patch for MJPEG decoding (libavcodec/mjpeg.c)
forces the use of the segment length when skipping for
certain marker types.

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====