Photoshop Image Resources
Photoshop Image Resources is a metadata format native to PSD files, but which is also used in TIFF and JPEG files. It may be informally known as "8BIM", after the signature which begins each data block.
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.
Not all Resource IDs are publicly documented.
In a TIFF file, tag 34377 contains Photoshop Image Resources.
In a JPEG file, an APP2 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.