Package: graphicsmagick
Version: 1.4+really1.3.38-1
Severity: minor
Control: found -1 1.4+really1.3.36+hg16481-2
Control: found -1 1.4+really1.3.35-1~deb10u2
[Please do not Cc: me, for I’m “on the list,” so to say, and
I try to reserve my inbox for private communication only.
I’d have set up Mail-Followup-To:, but there doesn’t seem to
be a way to make it point to the report being filed.]
While graphicsmagick claims to support ‘Truevision Targa’
format, its implementation is apparently slightly defective
in that the images are read and written with their vertical
axis reversed. Consider, for instance, SHAPES.TGA from [1]:
it’s shown with the gray (#9c9c9c) ‘floor’ at the bottom of
the image by both LDPCXTGA.EXE and ImageMagick’s display(1),
yet $ gm display SHAPES.TGA shows the floor at the /top/ of
the image instead.
[1] http://archive.org/download/simtelnet_bu_mirror_2013_04
/simtelnet.bu.mirror.2013.04.zip/simtelnet%2Fmsdos%2Fgraphics
%2Fldpcxtga.zip (URI split for readability.)
The same applies to images produced with $ gm convert.
The obvious workaround is to use -flip, like:
$ gm display -flip SHAPES.TGA
$ gm convert input.file -flip output.tga
--
FSF associate member #7257 http://am-1.org/~ivan/
