![]() Note1: There are also some other types compression algorithm, I just did most popular ones. So, hard to say which one is the best, it's up to your application needs. The ratio is the percentage reduction for each file compressed or decompressed(compatible with gzip -v)Īs you can see who's the best, you trade off either time cost or space, but generaly speaking, gzip is better than compress on both time and space saving, while lzma does the best on space saving, but it takes horribly long, if you have use case need to save space or compress once then uncompress a lot, it is the best option for uncompress time is incredibly fast. I made a large file out of many of small archive files for this test, 5GiB.Įven though there is no disk bottle nect, I load file into memory before each test, so that there is no io concern at all.Įach tool utility has compression levels, I test level(fast) 1, 6(default) and 9(best). ![]() In the test below, I chose data file(like text file, but without space,tab and newline etc.), which generated log file by Postgresql. Generally speaking, binary and text file should be good and fair for all compression algorithms. doc or pdf can not be simply used as test sample file because they may have image in the document. TestChosing sample file is also a trick task, the principle is that I don't want to use some files which already zipped, for example, image,audio,video files. Small code size for decompression: 2-8 KB (depending on speed optimizations) Small memory requirements for decompression: 8-32 KB + DictionarySize LZMA uses a dictionary compression algorithm (a variant of LZ77 with huge dictionary sizes and special support for repeatedly used match distances), whose output is then encoded with a range encoder, using a complex model to make a probability prediction of each bit.Ĭompression speed: 2 MB/s on 2 GHz dual-core CPU.Ģ0-30 MB/s on 2 GHz Intel Core2 or AMD Athlon 64.ġ-2 MB/s on 200 MHz ARM, MIPS, PowerPC or other simple RISC CPU. The SDK history file states that it was in development from 1996, and first used in 7-Zip. It has been under development since 1998. LZMAThe Lempel–Ziv–Markov chain algorithm ( LZMA) is an algorithm used to perform lossless data compression. To use gzip, you know how to use bzip2More detail in Line flags are similar to those of GNU Gzip, so if you know how Within 10% to 15% of the best available techniques (the PPMįamily of statistical compressors), whilst being around twice asįast at compression and six times faster at decompression. High-quality data compressor, uses Burrows–Wheeler algorithm. GNU project and is now relatively popularīzip2 is a freely available, patent free, Its main advantages over compressĪre much better compression and freedom from patented algorithms. Replacement for compress, uses deflate compression algorithms. Gzip gzip (GNU zip) is a compression utility designed to be a ![]() More detail about LZW, see the following links If no files are specified, the standard input will be uncompressed to the standard output. The uncompress utility will restore files to their original state after they have been compressed using the compress utility. In this article, I'll have a simple introduction about 4 tools and their libraries, followed by a test metric.Ĭompress is a Unix compression utility based on the LZC compression method, which is an LZW implementation using variable size pointers as in LZ78. Another word, most of them have same kernel. Rather, I'd like to only compare 4 of them.īecause behind these compression tools, there are actually several libraries. I'm not going to do the same thing again. -r Option: This will compress all the files in the given directory and sub-directories recursively.There are numerous compression tools available on linux, more for other platforms, you can find lots of comprehesive compreson articles too.Compression is attempted even if the results will be larger than the original. -c Option: Compressed or uncompressed output is written to the standard output.Compress example.xls and rename that file to with a percentage reduction of 70.41%. This option is ignored if the -c option is also used. -v Option: It is used to print the percentage reduction of each file.chpasswd command in Linux with examples.continue command in Linux with examples.compress command in Linux with examples. ![]() ISRO CS Syllabus for Scientist/Engineer Exam.ISRO CS Original Papers and Official Keys.GATE CS Original Papers and Official Keys.Full Stack Development with React & Node JS(Live). ![]()
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