How to create multiple variants of a single image with a single command

[felixranesberger]

I would like to generate multiple sizes of a given image using a single command.
The image output filenames should be configurable and result in a filename containing the current width and height of the variant.

image-500x500.webp
image-1000x1000.webp

Is this possible?

The reason for not using multiple commands is that they may impact performance, because we have to read the image data first for every image variant. Or is this neglectable?