algoritmi-fgk-compression

A C compressor, based on Adaptive Huffman Coding (FGK)

Requirements

The project itself doesn't require anything more than gcc, but some of the make targets (like massif, valgrind, callgrind) require the following debugging tools.

Debugging tools

• Valgrind
• Python
• xdot

Documentation generator

• Pandoc

Compilation

VIZ can be compiled with the following command:

make

The output will be a viz binary, that can be called with ./viz.

Make Targets

Warning: massif, valgrind and valgrind WON'T work if INVERTED_COMPRESSION_FLAG is set to 1 (check the define.h file)

all

Compiles the debug version of Viz (viz).

release

Compiles a release version (optimized, with no debugging symbols and no debugging messages). The output file is named viz-release.

test

Performs the tests specified in the main.c file. When they fail, the make build will fail to have a better integration w/ Jenkins.

debug

Generates a debugging version of viz compressor. This version won't be optimized, but it will include all the debugging symbols needed in case of problems. Watch out, the debugging mode is really verbose. You have been warned.

massif

This target compiles the debug version of Viz, and creates a viz.massif file that is then automatically opened with massif-visualizer.

massif_test

Same as massif, but tested against the viz-test binary (with no arguments)

massif_prod

Same as massif but tested against the viz-release binary. The debug arguments are used.

valgrind

Performs a Valgrind check on the debug binary.

callgrind

Generates a viz-debug.callgrind file of viz (debug).
After the file is generated, it is converted with python utilities/gprof2dot/gprof2dot.py to a .dot file that is then automatically visualized with xdot.

callgrind_release

Same as callgrind, but using the viz-release binary

callgrind_alice

Does the same as callgrind but uses the DEBUG_ARGS_ALICE arguments instead (it does compress the test/files/provided/alice.txt)

callgrind_alice_release

Same as callgrind_alice but, uses the viz-release binary.

docs

Builds the documentation. The generated artifacts are then written to docs/{readme,documentation}.pdf

clean

Performs a cleanup of the directory (warning: *.viz files are removed too!)

Compression

Compression is performed with viz -c output-file.viz input-file, where input-file can be either a file or a directory.

Decompression

You can decompress a .viz file with viz -d input-file.viz.

Usage

Depends on INVERTED_COMPRESSION_FLAG (check define.h)

INVERTED_COMPRESSION_FLAG = 1

VIZ compressor v2.0.0 (R-2.0.0-24-g4d0dc0b-dirty)
Compress:        viz -c inputfile output.viz
Extract:         viz -d input.viz

INVERTED_COMPRESSION_FLAG = 0

VIZ compressor v2.0.0 (R-2.0.0-24-g4d0dc0b-dirty)
Compress:        viz -c output.viz inputfile
Extract:         viz -d input.viz

Roadmap

October 4, 2017

First commit

January 19, 2018

Deadline

Resources

Adaptive Huffman Coding - FGK - Stringology.org
Adaptive Huffman Coding - Wikipedia
Adaptive Huffman Coding - The Data Compression Guide
Adaptive Huffman Coding - cs.duke.edu
Visualizing Adaptive Huffman Coding - Ben Tanen
Array Implementation for Complete Binary Trees