Package Exports

nrv2e-decompress

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (nrv2e-decompress) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

nrv2e-decompress

Decompress with NRV2E algorithm.

Requirements

This module requires ES5 with Node >= 4.

Installation

npm install nrv2e-decompress

Additionally for Typescript:

npm install -D @types/node

Usage

const { nrv2eDecompress } = require('nrv2e-decompress')

Typescript:

import nrv2eDecompress from 'nrv2e-decompress'

Transpiling this module with own settings in tsconfig.json:

{
  "compilerOptions": {
    "paths": {
      "nrv2e-decompress": ["node_modules/nrv2e-decompress/src/nrv2e-decompress"]
    }
  }
}

nrv2eDecompress

nrv2eDecompress(input, output, bufferBits)

Arguments:

input is a Buffer with compressed data
output is a Buffer from decompressed data and it have to be pre-allocated, ie. with Buffer.alloc method
bufferBits is a number of control buffer bits: 8, 16 or 32 (optional: default: 8)

Example:

// Polish vehicle registration certificate scanned from Aztec 2D barcode
const b64Input = 'BgQAANtYAA...'
const binInput = Buffer.from(b64Input, 'base64')

// 4 first bytes in Aztec code are output length
const outputLength = binInput.readUInt32LE(0)
const utf16Output = Buffer.alloc(outputLength)
const compressedInput = binInput.slice(4)

nrv2eDecompress(compressedInput, utf16Output)

const textOutput = utf16Output.toString('utf16le')

License

This code is based on UCL data compression library:

GPL-2.0