Photoshop Image Resources
Photoshop Image Resources consists of a sequence of blocks, each with a numeric Resource ID indicating the type of data stored in the block. Each block also contains a name, but the name is often left empty.
Each block begins with ASCII characters "8BIM", a signature which appears in several Photoshop formats.
Not all Resource IDs are publicly documented.
In a TIFF file, tag 34377 contains Photoshop Image Resources.
In a JPEG file, an APP13 marker with an identifier of "Photoshop 3.0" contains Photoshop Image Resources.
Resource ID 0x0404 contains IPTC data.
Resource ID 0x040c may contain a thumbnail in JPEG/JFIF format.
Resource ID 0x040F contains an ICC profile.
Resource ID 0x0422 contains Exif data.
Resource ID 0x0424 contains XMP data.