I'd need a tool that can handle a fairly large number of fairly-large images (1920 PNGs of 2048x2048 pixels each). My first thought was to use ImageMagick, but that turned out be useless — it appears to be lacking the kind of proper memory management that is necessary when you're dealing with large amounts of data, not just more data than will fit in memory (or memory plus swap, for that matter) but also more data than a 32-bit process can allocate on a 32-bit OS to begin with.
The source files themselves are fairly small, less than 50 MB of data in total. I could easily convert these files to a different format that's more suitable for processing, too; it would be nice if the final resulting image would be in a fairly well-compressed format such as PNG, but it's not a requirement — actually compressing an 8 gigapixel image might take too long for it to be feasible, and PNG compression might also interfere with easy viewing of the result, so if I'd end up with an uncompressed bitmap, that'd be fine.
Speaking of which, I'd also like a recommendation for an image viewer: one that would allow swift zooming in/out of and panning across an image that size.
I'm sure there are people who regularly have to deal with this sort of problem, and as such I'm sure there are solutions for this. Any pointers?
(And yes, this is about xkcd.)