Christian Heilmann

Creating a set of icons in various sizes in the browser

Friday, August 15th, 2014 at 9:37 pm

Hooray, I did do some coding again for a change! One of the issues I had with submitting apps for the Firefox Marketplace is that the validator of the manifest always complains about me missing out on certain icon sizes. That’s why I thought it’d be sweet to have an in-browser tool to generate all of the icons one needs from an image. And here it is:

icon generator in action

You can see a demo of it working on YouTube:

That’s all there is to it – it uses Canvas and the fileReader API to convert the images and create the files. JSZip, a neato library to create Zips was also in use.

For now your original image needs to be square and 512×512 pixels or the generator will just paste the first 512×512 pixels in. Images are automatically resized to 512 pixels and centered on a transparent background. A later version might allow you to move the image around. Let’s see when I get the time.

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