Allow specifying exact image scaling factors
When displaying multiple images on a single slide, sometimes it is important to show them at the same, but enlarged (or reduced) scale. If the images have different width/height originally, then it is difficult to resize them manually and keep the same resolution.
E.g. I have multiple snippets of terminal window screenshots I want to place on the same slide, and all of them have different width/height, but if I scale them to different amounts, that will result in different text sizes and will look messy. Doing that by hand is difficult and tiresome.
As a solution, provide a way to enter a specific scaling factor for images. One scaling factor (e.g. percents) for images keeping the aspect ratio, and two for the others.