Comparing buffers

[philmirez]

Hello 👋

I would like to compare two images in memory as opposed to relying on reading and writing from the file system.

I might be going about this the wrong way and if so I'd appreciate some sort of hint/help.

I've created a repo showcasing what I'm seeing: https://github.com/philmirez/comparing-buffers

• The result diff image looks like red static (see examples/diff.png)
• Both images have the same dimensions 1101 x 2614 (see examples/prodScreenshot.png and examples/stagingScreenshot.png).

Side note: One thing that threw me off was when I was reading the pixelmatch/index.js file, it says...

if (img1.length !== width * height * 4) throw new Error('Image data size does not match width/height.')

I don't understand why width and height are being multiplied by 4.

[philmirez]

Never mind, I was able to find help on stackoverflow.