[mro_name]

what was the issue - hardware access (a CD reader), bit rot or else?

The image format was jpeg if I remember correctly, wasn't it?

[mark-r]

I don't think it was JPEG, it was a custom format that contained multiple resolutions.

[dhosek]

It's a custom undocumented format with a lot of oddities to it (particularly in its color profile handling, or more precisely lack thereof).