[mythtv] mythtv commit: r8651 by danielk (Auto Aspect Ratio transcode)

Endaf Jones jonese at zener.com
Thu Jan 19 22:42:50 UTC 2006

> Modified:
>   trunk/mythtv/libs/libmythtv/videobuffers.cpp
> Log:
> Fixes #1053.
> In this case an MPEG-4 recording is using a frame height which is not
> a multiple of 16. ffmpeg isn't doing any validation on the dimensions
> so it ends up writing outside the buffer. This just pads allocated
> buffers up to multiples of 16, so that this type of error doesn't cause
> a segfault with any of the codecs we support. MythTV does prevent you
> from setting an invalid dimension when you record to a MPEG-4 NUV, so
> AFAIK this is more of a legacy issue.


What about transcoding MPEG2 into MPEG4 after a recording and you have
"Resize Video while transcoding" AND the newly developed "Preserve
Aspect Ratio of Video when resizing" option?  The height is auto
calculated in that case.

Is this situation the same as the above commit?

I say this because I have a PBS HDTV program 1920x1080i that I
transcode into a 544 wide MPEG4 so I can view it on my SDTV.  The
height works out to be 302 or so pixels (to keep the aspect correct). 
When I play that newly encoded file, I have a strange color cast on
the top 1/6th of the picture.

Same problem or different?

# Endaf

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