My algorithm for scaling a bitmap b of size w1 × h1 to a bitmap of size w2 × h2:
The algorithm above is not the most efficient one to get the result. I only use it to describe the effect of the scaling algorithm (and I can do it in Photoshop instead of writing a program). Is there a known algorithm that produces the same result as mine?
I found a detailed description here: http://entropymine.com/imageworsener/pixelmixing/.
It’s sometimes called pixel mixing, pixel averaging, or area map, among other things.