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codext also adds common binary encodings. For instance, the Manchester code, that encodes digits, is applied to the ordinals of the input text and the resulting binary stream is converted back to characters.


It supports various formats such as CCITT-1 and CCITT-2, ITA1 and ITA2, and some others.

Codec Conversions Aliases Comment
baudot text <-> text Baudot code bits baudot-ccitt1, baudot_ccitt2_lsb, ...
baudot-spaced text <-> Baudot code groups of bits baudot-spaced-ita1_lsb, baudot_spaced_ita2_msb, ... groups of 5 bits are whitespace-separated
baudot-tape text <-> Baudot code tape baudot-tape-mtk2, baudot_tape_murray, ... outputs a string that looks like a perforated tape


"_lsb" or "_msb" can be specified in the codec name to set the bits order. If not specified, it defaults to MSB.

>>> codext.encode("12345", "baudot-fr")
>>> codext.decode("010000000100010001000010100111", "baudot-fr")
>>> codext.encode("TEST", "baudot-spaced_uk")
'10101 00010 10100 10101'
>>> codext.decode("10101 00010 10100 10101", "baudot-spaced_uk")
>>> s = codext.encode("HELLO WORLD!", "baudot-tape_ita2")
>>> print(s)
* *.  
   . *
*  .* 
*  .* 
** .  
*  .**
** .  
 * .* 
*  .* 
 * . *
** .**
 **. *
>>> codext.decode(s, "baudot-tape_ita2")

Binary Coded Decimal (BCD)

It converts characters to their odrinals, left-pads with zeros, converts digits to 4-bits groups and then make characters with the assembled groups. It can also use a 4-bits prefix for making new characters. It then allows to define extended versions of BCD.

Codec Conversions Aliases Comment
bcd text <-> BCD encoded text binary_coded_decimals
bcd-extended0 text <-> BCD encoded text using prefix 0000 bcd_ext0, bcd-extended-zeros, binary_coded_decimals_extended_0
bcd-extended1 text <-> BCD encoded text using prefix 1111 bcd_ext1, bcd-extended-ones, binary_coded_decimals_extended_1
>>> codext.encode("Test", "bcd")
>>> codext.decode("\x08A\x01\x11Q\x16", "binary_coded_decimal")
>>> codext.encode("Test", "bcd_ext_zero")
>>> codext.decode("\x00\x08\x04\x01\x00\x01\x01\x01\x05\x01\x01\x06\x00", "bcd-ext0")
>>> codext.encode("Test", "bcd_extended_ones")
>>> codext.decode("\xf0\xf8\xf4\xf1\xf0\xf1\xf1\xf1\xf5\xf1\xf1\xf6\xf0", "bcd_ext1")


Also called Stibitz code, it converts characters to ordinals, left-pads with zeros and then applies Excess-3 (Stibitz) code to get groups of 4 bits that are finally reassembled into bytes.

Codec Conversions Aliases Comment
excess3 text <-> XS3 encoded text excess-3, xs3, stibitz
>>> codext.encode("This is a test!", "excess-3")
>>> codext.decode(";t7C\x84H6T8D\x83e<£eD\x944D\x84I6`", "stibitz")
'This is a test!'


Also called reflected binary code, it implements the Gray code applied to characters while converted to bytes.

Codec Conversions Aliases Comment
gray text <-> gray encoded text reflected-bin, reflected_binary
>>> codext.encode("this is a test", "gray")
>>> codext.decode("N\\]J0]J0Q0NWJN", "gray")
'this is a test'
>>> codext.encode("THIS IS A TEST", "gray")
>>> codext.decode("~lmz0mz0a0~gz~", "gray")


This codec XORes each group of 4 bits of the input text with a 1-byte clock signal, e.g. 0x55 giving in binary 01010101.

Codec Conversions Aliases Comment
manchester text <-> manchester encoded text clock signal is 0x55 (01010101)
manchester-inverted text <-> manchester encoded text ethernet, ieee802.4 clock signal is 0xaa (10101010)
>>> codext.encode("This is a test!", "manchester")
>>> codext.decode("fei\x95i\x96jZYUi\x96jZYUiVYUjeifjZjeYV", "manchester")
'This is a test!'
>>> codext.encode("This is a test!", "manchester-inverted")
>>> codext.decode("\x99\x9a\x96j\x96i\x95¥¦ª\x96i\x95¥¦ª\x96©¦ª\x95\x9a\x96\x99\x95¥\x95\x9a¦©", "ethernet")
'This is a test!'

Rotate N bits

This codec rotates of N bits each byte of an input string.


This codec does not use the "<<" and ">>" operators as it is lossy in some cases. Instead, it rotates per group of 8 bits.

Codec Conversions Aliases Comment
rotate text <-> N-bits-rotated text rotate-N, rotate_bits-N, rotate-right-N, rotate_left_N N belongs to [1,7] ; when nothing specified, it rotates to the right
>>> codext.encode("test", "rotate-1")
>>> codext.encode("test", "rotatebits-1")
>>> codext.encode("test", "rotate_right-1")
>>> codext.encode("test", "rotate_left_1")