MDI

MDI is a proprietary image format used by Microsoft Office Document Imaging.

It is almost identical to TIFF, but has a different header, and may use one of several undocumented compression schemes.

Identification
Files begin with bytes.

Compression
The compression schemes are reportedly defined as follows:

Other sources give the following, but 34719 and 34720 may have been accidentally swapped.

Links

 * Microsoft Document Imaging Format
 * Microsoft Office Document Imaging
 * Media type registration
 * Possibly related: Fast Progressive Image Coding Without Wavelets