msvidc32/msvideo1 question: upside down buffers?
m.b.lankhorst at gmail.com
Tue Apr 6 11:46:12 CDT 2010
On 06-04-10 17:47, Joerg-Cyril.Hoehle at t-systems.com wrote:
> does anybody know why msvideo_decode_8bit(), when imported
> from the FFmpeg project in 2004, was changed such that the
> pixels array became filled upside down? See how
> #ifdef ORIGINAL,
> which shows the original FFmpeg code, differs from the
> branch in msvideo1.c
> Do buffers in Wine work upside down and backwards?
> Why can't Wine use exactly FFmpeg's code?
> I'm asking because no similar set of changes was applied to
> msvideo_decode_16bit(). I have files that are rendered
> incorrectly and even suspect of crashing Wine because of
> this. I could write a patch but need to know.
See BITMAPINFOHEADER documentation for biHeight:
However not all codecs handle negative height properly, and just ignore
the information the sign gives. This is probably why ffmpeg puts it
upside down internally.
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