Utility Library for Comparing Uint8ClampedArrays

 

Installation
-------
npm install uint8clampedarray-utils
yarn add uint8clampedarray-utils

Usage
-----
#### isEqual
Check if two values are equal Uint8ClampedArrays.
=> Promise
``js
// Promise is resolved if equal
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3]);
await isEqual(a, b) // => true;

// Promise is rejected on difference
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([3, 2, 1]);
await isEqual(a, b) // => throws Error;

// Promise is rejected when called with non Uint8ClampedArray value
const a = [1, 2, 3];
const b = new Uint8ClampedArray([1, 2, 3]);;
await isEqual(a, b) // => throws Error;
`

#### isEqualSync
Check if two values are equal Uint8ClampedArrays.
=> Boolean
`js
// Returns true/false
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3]);
isEqualSync(a, b) // => true

// Pass flag to throw error on invalid arguments/difference
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3, 4]);
const throwError = true;
isEqualSync(a, b, throwError) // => throws Error
`

#### diff
Calculate difference between two Uint8ClampedArray.
=> Promise
`js
// Promise is resolved with statistics object
const a = new Uint8ClampedArray([1, 2, 3, 4]);
const b = new Uint8ClampedArray([1, 2, 3, 5]);
await diff(a, b) // => { diffCount: 1, diffPercentage: 25 }

// Set the step size to 4 if you want to check for pixel differences in RGBA array
const a = new Uint8ClampedArray([0, 0, 0, 0, 255, 36, 17, 50]);
const b = new Uint8ClampedArray([0, 0, 0, 0, 0, 0, 0, 0]);
const stepSize = 4;
await diff(a, b, stepSize) // => { diffCount: 1, diffPercentage: 50 }

// Promise is rejected on difference in length
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3, 4]);
await diff(a, b) // => throws Error;

// Promise is rejected when called with non Uint8ClampedArray value
const a = [1, 2, 3];
const b = new Uint8ClampedArray([1, 2, 3]);;
await diff(a, b) // => throws Error;
`

#### diffSync
Calculate difference between two Uint8ClampedArray.
=> Object
`js
// Returns statistics object
const a = new Uint8ClampedArray([1, 2, 3, 4]);
const b = new Uint8ClampedArray([1, 2, 3, 5]);
diffSync(a, b) // => { diffCount: 1, diffPercentage: 25 }

// Set the step size to 4 if you want to check for pixel differences in RGBA array
const a = new Uint8ClampedArray([0, 0, 0, 0, 255, 36, 17, 50]);
const b = new Uint8ClampedArray([0, 0, 0, 0, 0, 0, 0, 0]);
const stepSize = 4;
diffSync(a, b, stepSize) // => { diffCount: 1, diffPercentage: 50 }

// Throws Error on difference in length
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3, 4]);
diffSync(a, b) // => throws Error;

// Throws Error when called with non Uint8ClampedArray value
const a = [1, 2, 3];
const b = new Uint8ClampedArray([1, 2, 3]);;
diffSync(a, b) // => throws Error;
`

#### isUint8ClampedArray
Check if value is Uint8ClampedArray. Basically a wrapper for value instanceof Uint8ClampedArray.
=> Boolean
`js
// Returns true/false
const arr = [1, 2, 3];
const uArr = new Uint8ClampedArray([1, 2, 3]);
isUint8ClampedArray(arr) // => false
isUint8ClampedArray(uArr) // => true
`

#### hasSameLength
Check if two Uint8ClampedArrays have the same length. Basically a wrapper for a.length === b.length.
=> Boolean
`js
// Returns true/false
const a = new Uint8ClampedArray([1, 2, 3]);
const b = new Uint8ClampedArray([1, 2, 3]);
hasSameLength(a, b) // => true

// Returns false when called with non Uint8ClampedArray value
const a = [1, 2, 3];
const b = new Uint8ClampedArray([1, 2, 3]);
hasSameLength(a, b) // => false

// Pass flag to throw error when called with non Uint8ClampedArray value
const a = [1, 2, 3];
const b = new Uint8ClampedArray([1, 2, 3]);
const throwError = true;
hasSameLength(a, b, throwError) // => throws Error
`

Running the tests
-----------------
yarn test
yarn coverage
yarn lint`

Support
-------
Please open an issue for support.

License
-------
MIT