PPMd is a compressed archive format developed by Dmitry Shkarin, and various compressed data formats derived from it. It uses Prediction by partial matching. It's intended to be used mainly by other software, instead of directly by end users.
It was originally named PPMD (PPM, escape method D), later PPMd (PPM by Dmitry).
PPMd files start with signature bytes
8f af ac 84.
The reversed signature
84 ac af 8f may also be possible, if the software is compiled for a big-endian system.
- 7z - Has a PPMd compression method.
- Zipx - Has a PPMd compression method.
- BMF (Dmitry Shkarin) - Same author