Node | Jimp | contrast
The contrast() function is an inbuilt function in Nodejs | Jimp that adjusts the contrast of an image by a value of -1 to +1.
Syntax:
contrast(n, cb)
Parameter:
- n: This parameter stores the amount to adjust the contrast, a number between -1 and +1
- cb: This is an optional parameter that is invoked when compilation is complete.
Input Images:
Setup Environment:
npm init -y
Install Dependencies:
npm install jimp
Example 1:
javascript
// npm install --save jimp // import jimp library to the environment const Jimp = require( 'jimp' ); // User-Defined Function to read the images async function main() { const image = await Jimp.read ( 'https://media.w3wiki.net/wp-content/uploads/20190328185307/gfg28.png' ); // contrast function image.contrast(.4) .write( 'contrast1.png' ); } main(); console.log( "Image Processing Completed" ); |
Output:
Example 2: With cb (optional parameters)
javascript
// npm install --save jimp // import jimp library to the environment const Jimp = require( 'jimp' ); // User-Defined Function to read the images async function main() { const image = await Jimp.read ( 'https://media.w3wiki.net/wp-content/uploads/20190328185333/gfg111.png' ); // contrast function using callback function image.posterize(.5, function (err) { if (err) throw err; }) .write( 'contrast2.png' ); } main(); console.log( "Image Processing Completed" ); |
Output:
Reference: https://www.npmjs.com/package/jimp