JavaScript image processing by native functions

Good day, reader!

Somehow I needed in the project running on node.js, image processing. And to download the file, put it in a folder and connect it as a module. But no, there were none in nature. Therefore, I had to use node-imagemagick . But now the post is not about this library.

The post that I wanted to make such a library that I downloaded, put the file into the project, connected the module and everything works! Well done. True gif 'ok support is not implemented, but I hope for a huge community that will be interested and will help to complete the library.

I called it simple, imageLib.js , and put it on github , though under MIT.

I didn’t make speed measurements, and there’s no need, it’s clear that it works slower than all existing ones. But for the idea it was worth it.
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Here is an example of reading a PNG image and then inserting a 200x200 pixel canvas with a black frame and a rectangle into this image:

var imageLib = require('./imageLib.js'); imageLib('./images/trees.png').pngToData(function() { var that = this; imageLib(200, 200).create(function() { var x, y; for(x=20; x < 180; x++) { for(y=20; y < 40; y++) { this.setPixel(x, y, 255, 0, 0, 255); // black } } for(y=0; y < this.height; y++) { this.setPixel(0, y, 255, 0, 0, 255); this.setPixel(this.width-1, y, 255, 0, 0, 255); } for(x=0; x < this.width; x++) { this.setPixel(x, 0, 255, 0, 0, 255); this.setPixel(x, this.height-1, 255, 0, 0, 255); } this.pasteTo(that, 10, 10, true); that.toPng('./images/trees_samp.png'); }); }); 

With the help of the library, you can read and write JPEG, PNG images, change their size. You can also find out the color and alpha channel of a pixel, or overwrite it. Well, respectively, copying one picture to another.

A complete list of functions and their examples can be found on the module page:

GitHub.com Link: github.com/lampaa/imageLib

Link to node.js: node.js