I normally process a large number of CR2 files which are a combination of Dual-ISO and standard format images. Is there an option, or perhaps a way to code cr2hdr to do a quick Dual-ISO test and exit if the image is not Dual ISO?
Currently it consumes a lot of time to make that determination before it errors out.
You can add a custom file prefix in camera for Dual-ISO images (there is an option to do that in Dual-ISO parameters), and apply cr2hdr.exe only to files with that custom file prefix.
Sounds like a plan! I'm glad I asked. There are usually many ways to skin the cat!