a2pix for Mac

From kJams Dot Com:

Allows you to open and view HGR and DHGR graphics on your Macintosh, and save to QuickTime PICT. Reads DazzleDraw, Beagle ".aux", 816 Paint and MouseDraw file types, or any graphic BSAVE pict,a$2000,l$2000. Does a fantastic job at DHGR, much more accurate than what the current batch of emulators have to offer. Converts batches. Many options for different color or black and white palettes including green or amber. Handles aspect ratio correction: with this turned on you'll get the correct proportions (ie: circles no longer look like ovals like they do in all emulators)

Added bonus: you may have noticed that the ProDOS FST has broken under OS 9. You can still mount and read actual floppies and disk images, but try to write to them and you'll corrupt your disk. Well, this program lets you read any file (<800k) and write it to a new ProDOS disk image.