QPress/QuickLZ
QPress is a demo archiving program which serves as a proof-of-concept for the QuickLZ library by Lasse Reinhold. The compressor is geared toward speed rather than compression ratio, much like GZip but even faster.
qpress 0.39 - Copyright 2006-2010 Lasse Reinhold - www.quicklz.com Using QuickLZ 1.4.1 BETA 3 compression library Compiled for: [Windows] *nix [x86/x64] RISC 32-bit [64-bit] Compression: qpress [-rcvfCBPLKT] <source file/dir search pattern> <destination file> <stdin> qpress [-cvfBPLKT] <filename to give stdin data> <destination file> Decompression: qpress -d[cvfBPTn] <source file> <destination directory> Benchmark and recovery: qpress -m[LT] <source file> qpress -R <corrupted compressed file> <destination directory> Flags: -d Decompress -Ln Set compression level to n where n = 1, 2 or 3 (default = 1) -r Include sub directories during compression -v Show progress information during compression and decompression -c Write to stdout instead of destination file or directory -f Overwrite existing files during compression and decompression (default is to abort) -C Continue if a source file cannot be opened during compression (default is to abort) -Tn Use n threads/cores where n = 1 to 256 (default = 2). Be aware of memory usage with large n -Kn Read from disk in n KiB chunks during compression where n = 64 to 32768 (default = 64). Be aware of memory usage with large n. -B Windows only: Disable file system caching (FILE_FLAG_NO_BUFFERING) to prevent cache of other applications from being be flushed. Keep enabled if files are small and need further processing. -Pn Windows only: Set CPU and disk I/O priority to n where 1 = BACKGORUND (Vista, 7, 2008 only), 2 = IDLE, 3 = NORMAL and 4 = ABOVE (default = 3)
| Command | 32-bit | 64-bit | Difference |
|---|---|---|---|
| Average | 3.619% | ||
qpress -L1 |
8.580 | 9.843 | 14.720% |
qpress -L2 |
14.476 | 14.664 | 1.299% |
qpress -L3 |
40.201 | 38.126 | -5.162% |