bit-coder

bitwise binary coding

bit-coder

A node.js library for bitwise binary encoding of data

var assert = require('assert');
var bitCoder = require('bit-coder');
 
// 1000 bits to write to. 
var wbs = new bitCoder.BitStream(1000);
 
// Write out some values. 
wbs.writeBits(100, 20);
wbs.writeUnary(20);
wbs.writeEliasGamma(2000);
 
// Pad and get the result 
var buf = wbs.wrap();
 
// Get a new bitstream removing the padding 
var rbs = bitCoder.BitStream.unwrap(buf);
 
// Check the contents. 
assert.equal(rbs.readBits(20), 100);
assert.equal(rbs.readUnary(), 20);
assert.equal(rbs.readEliasGamma(), 2000);

Construct a new BitStream backed by a new BitBuffer len bits.

Construct a new BitStream backed by an existing BitBuffer.

Construct a new BitStream backed by an new BitBuffer constructed from the existing buffer and optional length.

Construct a new BitStream from of buffer previously obtained from calling wrap. This is a Function method, not a prototype method.

The current read/write pointer; change this to seek.

The underling BitBuffer.

Pad a bit stream with 1 to 8 bits to the nearest byte boundary and return the slice of the underling Buffer that was written.

Read len bits (32 maximum) from the stream.

Write len (32 maximum) to the stream.

Write len bits with the lowest bit of v.

Write out the given value (v >= 1) in unary encoding

Read a unary encoded value from the stream

Write out the given value (v >= 1) in the indicated universal code

Read a value encoded with the indicated universal code

Write out the value v (0 <= v < n) in base n truncated binary representation

Read a base n truncated binary value from the stream

Construct a new BitBuffer len bits long backed by a Buffer on node.js or a Uint8Array in the browser.

Construct a new BitBuffer backed by the supplied Buffer or Uint8Array. The length is specified by the optional len, which is all the bits in the buffer if unspecified.

Retreive len bits (32 maximum) from the buffer at the supplied offset.

Set len (32 maximum) to the buffer at the supplied offset.

Fill len bits with the lowest bit of v at the supplied offset.

MIT