typedarray-base64-converter v0.0.2

TypedArray Base64 Converter

Introduction

Base64 allows transfer and store numbers as text in shorter form than decimal digits. See the demonstration below.
This package provides functions to encode and decode binary data from typed-array to base64.
Works on both NodeJS and Browsers.

Limitations

For now, the package only supports 8 bit arrays, e.g. Uint8Array | Uint8ClampedArray | Int8Array. The reason for that is to avoid big-endian<>little-endian problems. If there will be high demand to support more than 1 byte array, we will add it in a future version, in endianness safe way.

Requirements

This should work on any Browser that supports typed-arrays, excluding Android Browser v4-4.3, because it doesn't have charCodeAt & fromCharCode.

Installation

$ npm install --save typedarray-base64-converter

import { typedArray_to_base64, base64_to_typedArray } from "typedArray-base64-converter"

Usage

Example 1: unsigned integers

const myUintArray = new Uint8Array ([0,23,41,68,87,109,125,146,161,187,202,244])
// Uint8Array(12) [0,  23,  41,  68,  87, 109, 125, 146, 161, 187, 202, 244]

typedArray_to_base64 (myUintArray)
// 'ABcpRFdtfZKhu8r0'

base64_to_typedArray ('ABcpRFdtfZKhu8r0')
// Uint8Array(12) [0,  23,  41,  68,  87, 109, 125, 146, 161, 187, 202, 244]

Example 2: signed integers

const myIntArray = new Int8Array ([125, -110, -95, -69, -54, -12])
// Int8Array(6) [ 125, -110, -95, -69, -54, -12 ]

typedArray_to_base64 (myIntArray)
// 'fZKhu8r0'

base64_to_typedArray ('fZKhu8r0', Int8Array)
// Int8Array(6) [ 125, -110, -95, -69, -54, -12 ]

Demonstration

In comparison, of doing the same without base64 conversion:

JSON.stringify(typedArray_to_base64 (myUintArray))
// '"ABcpRFdtfZKhu8r0"'
 
JSON.stringify(myUintArray)
// '{"0":0,"1":23,"2":41,"3":68,"4":87,"5":109,"6":125,"7":146,"8":161,"9":187,"10":202,"11":244}'

JSON.stringify([...myUintArray])
// '[0,23,41,68,87,109,125,146,161,187,202,244]'

Methods & Properties

typedArray_to_base64 (typedArray)

Parameters:

• typedArray - The original array that should be encoded.

Returns a base64 string.

base64_to_typedArray (base64, arrayType?)

Parameters:

• base64 - The base64 string.
• arrayType (optional, default = Uint8Array) - The constructor of the original array.

Returns the same typed array as the original.

isSupported

A boolean constant