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Compressions

codext provides a few common compression codecs.


GZip

Codec Conversions Aliases Comment
gzip data <-> GZipped data decoding tries with and without the file signature
>>> codext.encode('test', "gzip")
'\x1f\x8b\x08\x00\x0esÛ_\x02ÿ+I-.\x01\x00\x0c~\x7fØ\x04\x00\x00\x00'
>>> codext.decode('\x1f\x8b\x08\x00\x0esÛ_\x02ÿ+I-.\x01\x00\x0c~\x7fØ\x04\x00\x00\x00', "gzip")
'test'

Lempel-Ziv

This implements the algorithm of Lempel and Ziv of 1977 and 1978.

Codec Conversions Aliases Comment
lz77 data <-> LZ77-compressed data
lz78 data <-> LZ78-compressed data
>>> codecs.encode("A test string !", "lz77")
' \x88\x0e\x86S\x99ÐA\x0029\x1aMÆq\x00\x84'
>>> codecs.decode(" \x88\x0e\x86S\x99ÐA\x0029\x1aMÆq\x00\x84", "lz77")
'A test string !'
>>> codext.encode("A test string !", "lz78")
'A\x00 \x00t\x00e\x00s\x03 \x05t\x00r\x00i\x00n\x00g\x02!'
>>> codext.decode("A\x00 \x00t\x00e\x00s\x03 \x05t\x00r\x00i\x00n\x00g\x02!", "lz78")
'A test string !'

PKZip

This implements multiple compression types available in the native zipfile library.

Codec Conversions Aliases Comment
pkzip_deflate data <-> Deflated data deflate, zip_deflate Python3 only
pkzip_bzip2 data <-> Bzipped data bz2, bzip2, zip_bz2 Python3 only
pkzip_lzma data <-> LZMA-compressed data lzma, zip_lzma Python3 only
>>> codecs.encode("a test string", "deflate")
'KT(I-.Q(.)ÊÌK\x07\x00'
>>> codecs.decode("KT(I-.Q(.)ÊÌK\x07\x00", "zip_deflate")
'a test string'
>>> codecs.encode("a test string", "bzip2")
'BZh91AY&SY°\x92µÏ\x00\x00\x01\x11\x80@\x00"¡\x1c\x00 \x00"\x1a\x07¤ É\x88u\x95Á`Òñw$S\x85\t\x0b\t+\\ð'
>>> codecs.decode("BZh91AY&SY°\x92µÏ\x00\x00\x01\x11\x80@\x00\"¡\x1c\x00 \x00\"\x1a\x07¤ É\x88u\x95Á`Òñw$S\x85\t\x0b\t+\\ð", "bz2")
'a test string'
>>> codecs.encode("a test string", "lzma")
'\t\x04\x05\x00]\x00\x00\x80\x00\x000\x88\n\x86\x94\\Uf\x14Þ\x82*\x11ëê\x93fÿý\x84 \x00'
>>> codecs.decode("\t\x04\x05\x00]\x00\x00\x80\x00\x000\x88\n\x86\x94\\Uf\x14Þ\x82*\x11ëê\x93fÿý\x84 \x00", "zip_lzma")
'a test string'