2009/1/6 Luka Napotnik <luka.napot...@gmail.com>: > I'm trying to use GraphicsMagic (the successor of ImageMagick) to > manipulate a GdkPixbuf image buffer. The problem is that the program > segfaults, probably due to the raw nature of the buffer which the Magick > API doesn't handle very good. > I'm opening the image buffer with MagickReadImageBlob() and then apply > some filters.
libMagick (usually) expects images as RGBARGBARGBA, with 16 bits for each value. GdkPixbuf is always RGBRGBRGB, or RGBARGBARGBA, with 8 bits per value. You will probably need to allocate a big chunk of memory and unpack your GdkPixbuf into that as 16-bit values, then call MagickReadImageBlob(). Going the other way, you'll need to build an empty GdkPixbuf (ie. one with memory allocated for it), then pack the libMagick buffer down into that from 16 to 8 bits. Other image processing libraries are more flexible in how they can represent pixels and can skip these pack/unpack steps. It depends what kind of processing you want to perform and whether some other library also has what you need. I help maintain vips: http://www.vips.ecs.soton.ac.uk Which can do RGB or RGBA with 8 bit values, but of course might not have the particular filter you need. John _______________________________________________ gtk-app-devel-list mailing list gtk-app-devel-list@gnome.org http://mail.gnome.org/mailman/listinfo/gtk-app-devel-list
