onesy Huffman Code

Own implementation of Huffman coding algorithm

_{MIT license     Production ready     UMD 11.9kb gzipped     100% test cov     Browser and Nodejs}

_{Very simple code     Modern code     Junior friendly     Typescript     Made with 💛}

Getting started

Add

yarn add @onesy/huffman-code

Use

  import OnesyHuffmanCode from '@onesy/huffman-code';

  // Make a new OnesyHuffmanCode instance
  // with an optional initial values
  // string to encode, already calculated probabilities and
  // already calculated values
  // On making an instance encoding will be made
  const onesyHuffmanCode = new OnesyHuffmanCode('Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce dolor sem, facilisis sed erat sit amet, pharetra blandit augue. Sed id placerat felis, malesuada rutrum nisl. In ultrices sed mauris finibus malesuada. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Integer cursus, odio id rutrum blandit, neque velit aliquam odio, at rhoncus elit est nec erat. Proin egestas mauris elit, sit amet molestie nisi semper at. Cras interdum massa nec molestie rutrum. Duis commodo venenatis justo, ac porta tellus pellentesque sed. Donec et nisi metus.');

  // Initial byte size value
  // is 589 bytes, and after using
  // above method, encoded byte size is 444 bytes
  // including huffman code dictionary,
  // which is 7.3 compression percentage

  // Encoded
  // or very simply onesyHuffmanCode.response
  const response = onesyHuffmanCode.encoded;

  // {
  //   "value": "AAL/AAgr6XUV8YbCGqY3XUfY4tSPAAoACDcaXTR5Z5laY83/KjrGGwAIalf7e3Hm01NakbIADo1TG66j7OfcAAoAA7frcxpjcTwl5vcjaTZ1uOg6N7K019r9ZUXG7AAFAABXzTVvM/NitAAEnVakbX4gmt7S0/irX6youN3merdVbnQmjRx5idQnka9FuNrTAAIdoEPRJozkGOLF+nsw1AAHfZyDSx06AAaz6bpuQ15n5oTxAAY5AAUVfYTSOk2AoAAK+/W5jTH2ZeiWe1aY3Wn0XXwmkft0YHwscqytMZVGZHyDo83vAAGWyeKo6tfiAAmsrTH2qY3XUa42VRKzTU6ldyDdHmeg6tLQgMV9fqrsyPrjZVErAAFAFfzfxTWON7iYc9pk3RNZ/KoAB+3HzhCO0K1irOVrJoVeiWpG838ACyPlGaanXUFXBA==",
  //   "values": {
  //       "r": "0000",
  //       "o": "0001",
  //       "u": "0010",
  //       "d": "00110",
  //       "c": "00111",
  //       "e": "010",
  //       "n": "0110",
  //       "p": "01110",
  //       "g": "0111100",
  //       "C": "01111010",
  //       "v": "01111011",
  //       "h": "0111110",
  //       "I": "01111110",
  //       "j": "01111111",
  //       "t": "1000",
  //       "i": "1001",
  //       "s": "1010",
  //       "l": "10110",
  //       "m": "10111",
  //       " ": "110",
  //       "a": "1110",
  //       ".": "111100",
  //       "q": "1111010",
  //       "f": "11110110",
  //       "S": "111101110",
  //       "P": "111101111",
  //       ",": "111110",
  //       "b": "1111110",
  //       "D": "11111110",
  //       "L": "111111110",
  //       "F": "111111111"
  //   },
  //   "values_encoded": "0000 ro 1 u 1 dc 1 e 1 n 1 p 2 g 1 Cv 1 h 1 Ij 4 ti 1 s 1 lm 1   1 a 2 . 1 q 1 f 1 SP 1 , 1 b 1 D 1 LF",
  //   "probabilities": {
  //       "L": 0.0017,
  //       "o": 0.0475,
  //       "r": 0.0526,
  //       "e": 0.0985,
  //       "m": 0.039,
  //       " ": 0.1511,
  //       "i": 0.0764,
  //       "p": 0.0187,
  //       "s": 0.0815,
  //       "u": 0.0526,
  //       "d": 0.0306,
  //       "l": 0.0407,
  //       "t": 0.0781,
  //       "a": 0.0696,
  //       ",": 0.017,
  //       "c": 0.0306,
  //       "n": 0.0441,
  //       "g": 0.0068,
  //       ".": 0.017,
  //       "F": 0.0017,
  //       "f": 0.0051,
  //       "h": 0.0051,
  //       "b": 0.0068,
  //       "S": 0.0017,
  //       "I": 0.0034,
  //       "C": 0.0034,
  //       "q": 0.0085,
  //       "v": 0.0034,
  //       "P": 0.0017,
  //       "D": 0.0034,
  //       "j": 0.0017
  //   },
  //   "efficiency": 0.991,
  //   "redundency": 0.037,
  //   "entropy": 4.138,
  //   "original_byte_size": 589,
  //   "values_byte_size": 102,
  //   "value_byte_size": 444,
  //   "encoded_byte_size": 546,
  //   "compression_ratio": 1.08,
  //   "compression_percentage": 7.3,
  //   "positive": true,
  //   "average_code_word_length": 4.175,
  //   "performance_milliseconds": 4,
  //   "performance": "4 milliseconds"
  // }

  // Decode
  // with onesyHuffmanCode.decode or OnesyHuffmanCode.decode a static method
  OnesyHuffmanCode.decode(response.value, response.values);

  // {
  //   "value": "Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce dolor sem, facilisis sed erat sit amet, pharetra blandit augue. Sed id placerat felis, malesuada rutrum nisl. In ultrices sed mauris finibus malesuada. Class aptent taciti sociosqu ad litora torquent per conubia nostra, per inceptos himenaeos. Integer cursus, odio id rutrum blandit, neque velit aliquam odio, at rhoncus elit est nec erat. Proin egestas mauris elit, sit amet molestie nisi semper at. Cras interdum massa nec molestie rutrum. Duis commodo venenatis justo, ac porta tellus pellentesque sed. Donec et nisi metus.",
  //   "original_byte_size": 589,
  //   "value_byte_size": 444,
  //   "performance_milliseconds": 7,
  //   "performance": "7 milliseconds"
  // }

Dev

Install

yarn

Test

yarn test

Prod

Build

yarn build