LPAQ is a high-ratio lossless compression tool from the PAQ family. It focuses on maximizing compression quality using context mixing techniques while remaining simpler and faster than full PAQ implementations.
Unlike common archive tools, LPAQ operates on single files only, so it is typically combined with tar when working with directories.
Installing LPAQ on Linux #
LPAQ is usually distributed as a single C++ source file.
Install build tools #
On Debian/Ubuntu:
1sudo apt update
2sudo apt install build-essential
On Fedora:
1sudo dnf install gcc gcc-c++ make
On Arch Linux:
1sudo pacman -S base-devel
Get the source code #
Download a version such as lpaq1.cpp from the PAQ/LPAQ collection.
Example:
1wget https://example.com/lpaq1.cpp
Replace with a trusted source for the variant you want.
Compile #
1g++ -O2 -o lpaq lpaq1.cpp
For better performance:
1g++ -O3 -march=native -o lpaq lpaq1.cpp
This produces an executable:
1./lpaq
Basic Usage #
LPAQ uses a simple encode/decode model.
Compress a file #
1./lpaq e inputfile output.lpq
Example:
1./lpaq e data.tar data.lpq
Decompress a file #
1./lpaq d output.lpq restored.tar
Working with directories #
Since LPAQ does not handle folders directly, use tar first.
Create an archive:
1tar -cf project.tar project/
Compress it:
1./lpaq e project.tar project.tar.lpq
Restore it:
1./lpaq d project.tar.lpq project.tar
2tar -xf project.tar
When to Use LPAQ #
LPAQ is best suited for:
- Text-heavy data
- Source code archives
- Logs and structured data
- Compression experiments and benchmarks
It is not ideal for:
- Already compressed files (images, video, zip files)
- Fast backup workflows
- GUI-based file management
Performance Notes #
LPAQ prioritizes compression ratio over speed. Compared to modern tools:
- Faster than full PAQ systems
- Slower than
gzipandzstd - Sometimes achieves higher compression on text-heavy datasets
Key Limitations #
- No built-in directory support
- No metadata preservation
- Single-file compression only
- Experimental nature (multiple variants exist with different behavior)
Summary #
LPAQ is a research-oriented compressor designed for maximum compression efficiency using context mixing. On Linux, it is straightforward to compile and use, but it works best when treated as a specialized tool rather than a general-purpose archiver.