Crop-Tool - similar to Adobe Photoshop Crop-Tool Options

[Hermann]

In Adobe Photoshop there is a tool called "Crop-Tool" and it is perfect for making thumbnails of Pictures.
For example: have an 1600x1200 Photo from my digital Camera and I want a 150x100 Thumbnail of it.
I don't know an easy way in PMview to reach this goal (of course without changing the proportions of the image)
With the Photoshop I can set the Crop-Tool to 150x100, then select an area of the picture (the proportions of the selection are of course fixed, unless I want them to be free) and when I press ENTER I have a perfect 150x100 Thumbnail (with the correct proportions).

It would be great if PMview had an similar tool.

My idea to achieve this is using the standard selection-tool of PMview.
In the "selection info"-window there could be a new check-box called "Resize output". When you check it, there are 2 new input-fields (width and height) an a new check-box "keep proportional".
Now my idea is, that when I select an area of the picture and check "Resize output" and set width to 150 and height to 150, nothing special happens; but when I press Crop (or Copy, or Cut) the output (with Copy and Cut of course not the direct output, but the data in clipboard) has now the size 150x100!
And when I check "Keep proportions" too, I could only select an area with the proportion 3:2 (so that the output doesn't look ugly without the correct proportions!).

Is my idea clear to you?
Would that be possible?

I think a lot of people would like this tool!