Another neat tool I stumbled across for batch image manipulation (colour + size + scale etc)
http://www.faststone.org/FSResizerDetail.htmNote upscaling an image is not recommended (as it will obviously lead to pixelation).
But once you have a screenset and decided on your image size / scale you may benefit from rescaling the images for faster screen loads etc {maybe more so with microcontrollers than windows to some extent... anyway I found it helpful working with ISO 7000 images for a vehicle dashboard to colour change them to 1 bit and then rescale them, then recolourise them for the dashboard
I've said before that there are ISO images of drill, mill and plasma tools here:
https://www.iso.org/obp/ui#searchJust search for "mill" "drill" "plasma" etc. They are 200x200 hence can be rescaled. Don't use them obviously on a commercial product as they are copyrighted without paying for them!!
Something such as this sort of thing {not by me!}
https://www.youtube.com/watch?v=7Ph1sAS8qXo