Here’s a way to back up iPhoto’s image comments into an easy-to-read flat directory structure. (Translation: one big folder.) You’d want to do this when archiving your photos to CD or DVD, or when trying to merge photo libraries, or when leaving iPhoto for another program, or at any other time you want your comments saved in a non-proprietary, easily readable format.
As you may have read last week, when I upgraded to iPhoto 4, all the image descriptions temporarily disappeared from my online photo albums. (I caught the problem on my own staging server before it appeared on this site.) The culprit was a change in the way iPhoto stores photo comments. Comments are now entirely gone from the easy-to-parse AlbumData.xml file; iPhoto now stores them in a binary format that appears to be proprietary.
AppleScript to the rescue. Last week’s script saved the comments to text files and generated a directory structure that exactly paralleled iPhoto’s library, with one text file for each comment. These files were in folders for each day, which were in turn inside folders for each month, etc., guaranteeing there would be no name conflicts. I had rejected using the internal ID of each picture (which would have allowed a flat conflict-free directory structure) because the ID wasn’t user-visible anywhere in the iPhoto interface, making comment files named for the ID difficult to map back to the original pictures.
One of the comments on that post asked for a version that generated the comment files in one folder, based on the image’s filename. That was a good idea. Though the filename is not guaranteed to be unique, it often is in practice. Most digital cameras save unique serial numbers for each picture as part of the filename. So this is enough for most people. (The exceptions would be if you have more than one digital camera using a similar naming convention, or if your camera is configured to reset its numbering between rolls.)
If you like guaranteed accuracy, use my original script; if you like simplicity, use the following alternate script. It will only save one of the conflicting comments if photo filenames are duplicated. Dropping the parallel folder structure simplified the script, since this version doesn’t need to employ any POSIX path manipulation.
Copy the following into Script Editor and run. Tested with iPhoto 4.0 on Mac OS X 10.3. (It may also work with earlier versions; drop me a comment below if you’ve tried it.)