bitstring is a Python package designed to help make the creation and analysis of binary data as simple and natural as possible.
It has been maintained since 2006 and now has many millions of downloads per year. You can try out the interactive walkthrough notebook on binder, or take a look at the static version.
4.1 beta now available
This version concentrates on what is perhaps bitstring's major weakness - speed. It's always been a pure Python module with no dependencies, which has a few advantages, but means it can't compete with C-coded extensions in terms of raw speed of operation.
Version 4.1 of bitstring has been rewritten to use the bitarray
type from the package of the same name as its underlying data type.
This lets us keep the API and functionality of bitstring but gains (most of) the speed of bitarray.
Huge kudos to Ilan Schnell for all his work on bitarray over the last 15 or so years.
The 4.1 beta should be fully functional - there are no known issues. To install the beta you need to specify the precise version:
python -m pip install bitstring==4.1.0b1
Please try it out and report any problems or observations. You shouldn't need to change any code - everything should just work the same as version 4.0, just faster.
Overview
- Create bitstrings from hex, octal, binary, files, formatted strings, bytes, integers and floats of different endiannesses.
- Powerful binary packing and unpacking functions.
- Bit-level slicing, joining, searching, replacing and more.
- Read from and interpret bitstrings as streams of binary data.
- Rich API - chances are that whatever you want to do there's a simple and elegant way of doing it.
- Open source software, released under the MIT licence.
Note
Version 4 of bitstring only supports Python 3.7 and later.
Use bitstring version 3.1 if you're using Python 2.7 or 3.6 or earlier.
Documentation
The manual for the bitstring module is available at Read the Docs. It contains a walk-through of all the features and a complete reference section.
Examples
Installation
$ pip install bitstring
Creation
>>> from bitstring import Bits, BitArray, BitStream, pack
>>> a = BitArray(bin='00101')
>>> b = Bits(a_file_object)
>>> c = BitArray('0xff, 0b101, 0o65, uint6=22')
>>> d = pack('intle16, hex=a, 0b1', 100, a='0x34f')
>>> e = pack('<16h', *range(16))
Different interpretations, slicing and concatenation
>>> a = BitArray('0x3348')
>>> a.hex, a.bin, a.uint, a.float, a.bytes
('3348', '0011001101001000', 13128, 0.2275390625, b'3H')
>>> a[10:3:-1].bin
'0101100'
>>> '0b100' + 3*a
BitArray('0x866906690669, 0b000')
Reading data sequentially
>>> b = BitStream('0x160120f')
>>> b.read(12).hex
'160'
>>> b.pos = 0
>>> b.read('uint12')
352
>>> b.readlist('uint12, bin3')
[288, '111']
Searching, inserting and deleting
>>> c = BitArray('0b00010010010010001111') # c.hex == '0x1248f'
>>> c.find('0x48')
(8,)
>>> c.replace('0b001', '0xabc')
>>> c.insert('0b0000', pos=3)
>>> del c[12:16]
New in version 4.0
-
New Python 3.7 minimum requirement. The code has been updated with type hints and legacy code removed.
-
Shorter and more versative properties are available.
>>> a = BitArray('u8=20') >>> a += '0b0011, f16=5.52' >>> a[12:].f16 5.51953125
-
A useful new pretty printing method. Gives a formatted view of a singe or two interpretations of the binary data.
>>> a = Bits(bytes=b'hello world!!') >>> a.pp('bin, hex', width=40) 0: 01101000 01100101 68 65 16: 01101100 01101100 6c 6c 32: 01101111 00100000 6f 20 48: 01110111 01101111 77 6f 64: 01110010 01101100 72 6c 80: 01100100 00100001 64 21 96: 00100001 21
-
LSB0 option (beta). This indexes the bits with the least significant bit being bit zero. This is the opposite way to the standard Python containers but is usual in some relevant fields.
>>> bitstring.lsb0 = True >>> s = BitArray('0b00000') >>> s[0] = 1 >>> s.bin '00001'
This feature is still considered a beta as there may be issues with edge cases, especially around the interaction with the 'stream' features of the
BitStream
andConstBitStream
classes. For most usage cases it should be solid though, so please report any bugs in the issue tracker. -
Command line usage. Useful for quick interpretations of binary data.
$ python -m bitstring int:16=-400 0xfe70
-
Support for 16 bit floating point types (both IEEE and bfloat).
Unit Tests
The 600+ unit tests should all pass. They can be run from the root of the project with
python -m unittest
Credits
Created by Scott Griffiths in 2006 to help with ad hoc parsing and creation of compressed video files. Maintained and expanded ever since as it became unexpectedly popular. Thanks to all those who have contributed ideas and code (and bug reports) over the years.
Copyright (c) 2006 - 2023 Scott Griffiths