PGF (Progressive Graphics File)

Progressive Graphics File (PGF) is a raster image file format that uses wavelet compression.

Disambiguation
This format is not related to the PGF (Portable Graphics Format) TeX macro package.

Format
PGF files (version 6, at least) begin with a 24-byte fixed header.

Identification
Files being with ASCII characters " ".

Software

 * libPGF: C++ library, and command-line utilities

Links

 * libPGF.org
 * Wikipedia article