Node Jimp | opacity

The opacity() function is an inbuilt function in Nodejs | Jimp which multiplies the opacity of each pixel by a factor between 0 and 1.

Syntax:

opacity(f, cb)

Parameter:

• f: This parameter stores the value by which the image is made opaque. It has a range of 0 to 1. 1 will turn the image completely transparent.
• 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: In this example, we will see the use of opacity().

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.geeksforgeeks.org/wp-content/uploads/20190328185307/gfg28.png');
    // opacity function
    image.opacity(.3)
        .write('opacity1.png');
}

main();
console.log("Image Processing Completed");

Output:

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.geeksforgeeks.org/wp-content/uploads/20190328185333/gfg111.png');
    // opacity function using callback function
    image.opacity(.5, function (err) {
        if (err) throw err;
    })
        .write('opacity2.png');
}

main();
console.log("Image Processing Completed");

Output:

Reference: https://www.npmjs.com/package/jimp