[FFmpeg-devel] [RFC] scale filter can create output which scale filter cannot accept on its input
mark at mdsh.com
Sun Sep 4 23:51:31 CEST 2011
I know this is a bit of a bizarre filter chain, It's constructed to
demonstrate the point I'm hoping to make, without using any of my code.
Clock10.mov is just a PAL DV, but I think any _interlaced_ file will do.
./ffmpeg -loglevel debug -i ~/Movies/Clock10.mov -vf
-pix_fmt yuv420p -vframes 1 -an -f rawvideo -y /dev/null
Essentially, the 'y' parameter in the slices of the output of the second
scale is not aligned by 4 (the first slice is, in fact, 26 lines high,
so the second slice starts at 26) so it is not valid for the input of
the third scale.
I don't think the output of this filter chain should throw an assert.
I stumbled upon this when trying to make the fieldorder filter do slices.
Sorry to have not included my suggestion for a patch! My brain is fried.
More information about the ffmpeg-devel