Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
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
f – 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.
Input Image
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
// Reading Image
const image = await Jimp.read
('/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");Output
Using Node JIMP – OPACITY() with 'cb' parameters
Example
const Jimp = require('jimp') ;
async function opacity() {
// Reading Image
const image = await Jimp.read
('/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");Output
523 Views
