SCZ Publisher's description
from Carl Kindman
SCZ - Simple Compression Utilities and Library
SCZ is a simple set of compression routines for compressing and decompressing arbitrary data. The initial set of routines implement new loss-less compression algorithms with perfect restoration (decompression). Recently, a set of lossy routines has been added for photo-image compression.
The library is called SCZ, for simple compression format. SCZ is intended as subroutines for calling within your own applications without legal or technical encumbrances. It was developed because the standard compression routines, such as gzip, Zlib, JPEG, GIF, etc., are fairly large, complex, and difficult to integrate-with, maintain, understand, have external dependencies, or had legal restrictions.
SCZ is intended to fill a niche: simple lightweight, self-contained, data-compress/decompress routines that can be included within other applications, and that permit the applications to compress or decompress data on-the-fly, during read-in or write-out by simple calls. This niche applies to your application especially if the other compression libraries are as large or more complex than your application itself. Other compression utilities do not appear to be intended for easily embedding within other applications, and often depend on multiple external libraries that may not be installed on a given system.
SCZ typically achieves 3:1 compression. On binary PPM diagram image files it often achieves a 10:1 compression. On text files such as XML, it often compresses by 25:1. On difficult files, it may achieve less than 2:1 reduction. Although zip and gzip usually achieve slightly higher ratios, SCZ makes trade-offs for simplicity, memory footprint, and run-time speed, - in that order -, with consideration to diminishing-returns. For example, when compressing a particular 10-MB file, gzip saved 8.2-MB, while SCZ saved 7.8-MB. Either way, that's a lot of space saved! Sure, we could go after that last 0.4-MB of compression, but that is where diminishing-returns comes in. To compress that extra bit would more than double the complexity and run-time of SCZ. SCZ's core compression and decomp routines are only 178 and 45 lines of code, respectively. The balance of the files provide convenient access methods to compress files, buffers, and streams. SCZ's core library is four files containing about 600 source lines. (In contrast, the commendable light-weight zlib has 3,360 source lines in 25 files.)
Although the scz routines are intended for compiling (or linking) into your applications, the package also includes two self-contained (example) application programs that are stand-alone compress/decompress utilities, along with Readme and header files for linking:
* Readme.txt - Info.
* scz.h - Header file, prototypes of user-callable SCZ routines. Include when linking to pre-compiled SCZ libraries.
* scz_core.c - Common internal routines and data variables used by SCZ.
* scz_compress_lib.c - Base compression functions.
* scz_decompress_lib.c - Base decompression functions.
* scz_streams.c - Convenience routines for stream-like access.
* scz_compress.c - Application program to compress files.
* scz_decompress.c - Application program to decompresses files.
What's New in This Release:В· Some very minor updates were released for the SCZ compression library routines and recursion tests.
В· Conditional compilation statements were added to the library files to avoid redefinitions in case they get included multiple times.
В· In the regression test generator, include statements were added for standard libraries that are now needed by gcc.
System Requirements:No special requirements.
Program Release Status: Minor Update
Program Install Support: Install and Uninstall