Aspect ratio.

[Ramirelli]

Not Graphic Design major. My eCommerce requires specific specs to list photos/images. Using PSP Pro ultimate I am stuck on getting aspect ratio.
my Image is Width 2938 Height 2000. My aspect ratio should be either 4.3 (preferably) or 5.4.
In PSP I go to Advanced - AI powered Settings there you see lock Aspect ratio with check mark, when I type the value 4.3 The Height setting of 2938 begins to decrease. This is where I do not find the logic on how to setp ratio. I do not believe my PSP software is flawed or bugged. I am using PSP for the sole purpose it is one time paid unlike Adobe Photoshop, you pay every month and sometimes you hardly ever use it..
If anyone could help to go around this will be grateful and much appreciated. I thank you all ever so much. Have a pleasant day.

[LeviFiction]

Aspect ratio is how many pixels Wide compared to how many pixels High. The most common way to do this is to crop the image because otherwise, you'll be stretching it to fit the new aspect ratio. Now, the question I have is, is the actual AR 4.3 or is it 4x3?

ar = width/height or long/short however you want to do it. It gives a fraction you can then use in the following two equations.

long = short * ar
short = long / ar

A 4x3 aspect ratio is 4 pixels on the long side for every 3 pixels on the short side. Or 4/3 = 1.3333333 repeating. Now let's say that our long side is 200px. Using the equation above to find the short side we divide 200/1.333333 = 150px.
So 200x150 = 4x3 aspect ratio. Likewise, if we use the equation above and multiply 150 * 1.333333 we get roughly 200. So we can always double-check our work by making sure both sides can be found by their respective equations.

Now let's do the same with your AR of 4.3. Again we start with a random long side of 200px. Short = 200/4.3 = 46.511 or roughly 47 after rounding. Do the reverse and we get Long = 46.511 * 4.3 = 199.99 or roughly 200. If we use the rounded number of 46 or 47 we get around 197 to 202. It's not as precise but it can be done. Though a 200/47 image is quite thin. More like a banner image than a normal portrait or landscape image. If that's what you need, it works.

Now let's do this with your image of 2938 x 2000. This image has an aspect ratio of 1.469. If we assume the ar should be 4x3, we'll use the ar of 1.333 then Height(short) = 2938 / 1.333333 = 2,203. So it'll increase in height stretching the image a bit. Or if we start with the height of 2000 * 1.333333 = 2,666.66 or 2667 after rounding. The end result being the width is now smaller and squished when using resize. Or if you use crop and set the rectangle to be 2667x2000 you'll lose some of the image but you can make sure to keep the correct stuff.

Again we do the same with 4.3 as our aspect ratio, if we keep the width we get a height of 2938 / 4.3 = 683 (2938x683). If we start with height we get 2000 * 4.3 = 8600. (8600x2000) I think 4x3 makes way more sense in which case you want to use 1.3333 in your AR if resizing (squash and stretch) or just set the final values in the crop tool if using crop.

Likewise a 5x4 = 1.25 and makes a lot more sense, requiring less distortion or cropping of your original comapred to 5.4. If it was actually an AR of 5.4 you'd get weird numbers like 10000x2000 or 2938x544.