I'm looking for one, but can't find it :)
Now here's why. I needed to take an existing image and crop it to a specific pixel size. This simple task is surprisingly hard in most image editors, because:
1) In most simple editors, the selection rectangle is not persistent: you draw it with the mouse, then it disappears as soon as you click elsewhere. This means that if I need a selection rectangle that's exactly 655 x 342 pixels, I have to get it right the first time. Not easy! Good-bye, Paint .Net.
2) In more capable editors, the selection rectangle "sticks" and you can resize it with the mouse. The editor in ACDSee 10 does that, for example. But would you believe it, it does not display the dimensions of the selection, so you can't tell if the rectangle has the right size. Bye-bye!
3) Even if the selection is sticky and sizeable, often it cannot be moved around the image to cover a different part of it. You can get the rectangle to the required size, but when you drag it around, it moves together with the pixels it contains, leaving a white spot in its original location. Bye-bye, Snagit editor!
Needless to say, Screenshot Captor gets all three tasks perfectly! But I couldn't find a way to open an arbitrary image :) I copied the image to SC's screenshot folder instead, but a File -> Open would still be very useful, if possible.
Oh, and for the procedure I was doing, there's one other thing that would help that no editor does (that I know of). Let me specify the dimensions first, in pixels or percentage, in a dialog box. Click OK, and the selection rectangle is placed on the image at the exact size and can then be moved around to select the desired area of the picture. That would really help a lot, because even with the sticky selection, it's not that easy to change the width or height by 1 pixel or so.
Not urgent, not critical, just a couple of things that would help me a lot when needed.