PPM(Prediction by partial matching) is a compression algorithm which has several variations of implementations. PPMd is the implementation by Dmitry Shkarin. It is used in the RAR and by 7-Zip as one of several possible methods.
ppmd-cffi is a python bindings with PPMd implementation by C language. The C codes are derived from p7zip, portable 7-zip implementation. ppmd-cffi supports PPMd var.H and PPMd var.I.
PyPPMd is a brother project that use python buffer protocol for interface. It supports PPMd var.H, and PPMd var. I on posix platforms(mac and linux). It supports CPython and PyPy.
You can find a manual at the readthedocs
As usual, you can install ppmd-cffi using python standard pip command.
pip install ppmd-cffippmd-cffi provide small utility compress/decompress files.
$ ppmd target.txt
$ ppmd -x target.txt.ppmd- Copyright (C) 2020,2021 Hiroshi Miura
- 7-Zip Copyright (C) 1999-2010 Igor Pavlov
- LZMA SDK Copyright (C) 1999-2010 Igor Pavlov
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
