How to find the color profile/space used by a photo?

Have you got Adobe Bridge or Lightroom? Bridge can sort by Colour Profile, but I cannot find a way to do it in Lightroom, though it must exist (if it does in Bridge). This will only work in Windows or on a Mac though.

Alternatively, in Windows the colour profile is reported as part of the image properties, so it would just be an entry in metadata. So I would guess it should not be difficult to write a script that queries the metadata for every image, but I am the wrong person to tell you how to do that.

You can use imagemagick's identify program for this.

Example:

$ identify -verbose example.jpg | grep -A1 Profile-icc 
Profile-icc: 560 bytes
  Adobe RGB (1998)

(I could not get this out with the exiv2 tool mentioned in another answer.)

i tricked nikon scan into using prophoto rgb by swapping out the stored adobe rgb profile and renaming prophoto rgb as adobe rgb within nikon scan. was trying to find out how i did it 8 years ago.. having some trouble with posterizing skin tones in the poor underexposed images, but it is for archive so in the future that may become easier...