How to resize an image in python, while retaining aspect ratio, given a target size?

Here is my approach,

aspectRatio = currentWidth / currentHeight
heigth * width = area

So,

height * (height * aspectRatio) = area
height² = area / aspectRatio
height = sqrt(area / aspectRatio)

At that point we know the target height, and width = height * aspectRatio.

Ex:

area = 100 000
height = sqrt(100 000 / (700/979)) = 373.974
width = 373.974 * (700/979) = 267.397

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