# How to change the opacity of an image in Node Jimp?

NodeJS – Opacity() is an inbuilt function that is used to change the opacity of the images. This function multiplies the opacity of each pixel by a factor between 0 and 1 to produce the output image.

## Syntax

opacity(f, cb)

## Definition of opacity() paramters

• – It takes a value between 0 to 1 as an input which will the paramtere to make the image opaque. Input 1 will make the image completely transparent.

• cb – This is also an optional parameter that can be invoked after the compilation is complete.

## Using Node JIMP – OPACITY()

Before proceeding to use opacity() functions, please check that the following statements are already executed for setting up the environment.

• npm init -y // Initialising the Node environment

• npm install jimp --save // Installing the jimp dependency

• Create an opacity.js file and copy-paste the following code snippet in it.

• Use node opacity.js to run the code.

Note − The method name should match with the JS file name. Only then it will be able to call the desired method.

### Example

const Jimp = require('jimp') ;

async function opacity() { // Function name is same as of file name
('/home/jimp/tutorials_point_img.jpg');
image.opacity(0.7)
.write('/home/jimp/opacity.png');
}

opacity(); // Calling the function here using async
console.log("Image is processed successfully");

## Using Node JIMP – OPACITY() with 'cb' parameters

### Example

const Jimp = require('jimp') ;

async function opacity() {
('/home/jimp/tutorials_point_img.jpg');
image.opacity(0.3, function(err){
if (err) throw err;
})
.write('/home/jimp/opacity.png');
}

opacity();
console.log("Image is processed successfully");