I want to be able to, being given a path to an image, convert that image into another image, but with a different format. By format I mean .png, .bmp .jpg .tiff, etc. In pse
Exploring outward from NSImage leads you to NSBitmapImageRep, which does exactly what you want.
Some of those iPhone questions are relevant as well, because the solution that works on both platforms (and the implementation behind the NSBitmapImageRep solution nowadays) is to use CGImageSource to read in the image and CGImageDestination to write it out.