[FFmpeg-devel] [PATCH] avcodec/pnm: avoid mirroring PFM images vertically

[Leo Izen]

On 11/16/22 06:43, Leo Izen wrote:
> PFM (aka Portable FloatMap) encodes its scanlines from bottom-to-top,
> not from top-to-bottom, unlike other NetPBM formats. Without this
> patch, FFmpeg ignores this exception and decodes/encodes PFM images
> mirrored vertically from their proper orientation.
> 
> For reference, see the NetPBM tool pfmtopam, which encodes a .pam
> from a .pfm, using the correct orientation (and which FFmpeg reads
> correctly). Also compare ffplay to magick display, which shows the
> correct orientation as well.
> 
> See: http://www.pauldebevec.com/Research/HDR/PFM/ and see:
> https://netpbm.sourceforge.net/doc/pfm.html for descriptions of this
> image format.
> 
> Signed-off-by: Leo Izen <leo.izen at gmail.com>


Bumping for review, thanks.

- Leo Izen