I have implemented the LZ77 compression/decompression algorithm in C++ as my project assignment in college. I've included also files for testing purposes, such as: input.txt, output.txt and decompressed.txt to better visualise the compression/decompression process.
A program is a command-line-parameters kind. It takes always 5 parameters:
-i input_file: Input file for compression/decompression-o output_file: Output file for compression/decompression-t mode: c for compression, d for decompression-n inputBufferSize: Size of input buffer (max match length)-k historyBufferSize: Size of history buffer (search buffer)
The algorithm works by replacing repeated occurrences of data with references to a single copy of that data existing earlier in the uncompressed data stream. The LZ77 algorithm operates on a buffer that slides through the input. The length of the buffer is the maximum distance to look back in the input for a match. The algorithm assumes that strings encountered earlier in the input stream are more likely to occur later in the input stream, and uses this assumption to decide which match to copy into the output stream.
g++ lz77.cpp main.cpp parameters.cpp functions.cpp -o mainIf you compile this as such, you will get a main.exe executable file. You can run it by typing:
./maininput.txt as [input file], output.txt as [output file]
It can be any file, not just .txt (e.g: jpg, png, bin, cpp, etc.)
./main -i input.txt -o output.txt -t c -n 10 -k 10output.txt as [input file], decompressed.txt as [output file]
./main -i output.txt -o decompressed.txt -t d -n 10 -k 10If you like this project, please consider giving it a star. Thanks!
The project is not under any license, but with human kindness, I would like to be credited if you use it in your project. Thank you!