Is there a way to do a perspective distortion like this http://www.imagemagick.org/Usage/distorts/#perspective in GraphicsMagick? Of course, I can always switch back to ImageMagick, but I'd rather not.
I'm planning to use it in PHP, but command line is an option, too.
Graphics Magick appears not to support the -distort option, as per this discussion. http://comments.gmane.org/gmane.comp.video.graphicsmagick.core/460
I imagine it would be possible to use Graphics Magick for most of your operations, and use Image Magick for the distortion operation, if the performance gains in other areas are important.