Dephi selection area

I need to give users the ability to select some area of a picture inside my Delphi application (i.e. draw selection area on the picture)

What is the best way to do it ?
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Generally, you record the x,y coordinates in the mousedown and mouseup events.  These constitute two opposite corners of a rectangle.

You can enhance the UI by 'overlaying' the current rectangle over the picture in the mousemove event (if the left mouse button is depressed, of course)
Great components that were commercial but are now freeware:
You just drop a TImageEnView on your form, change the MouseInteract properties and then you can refer to the selection by saying e.g.
//To Crop to the selection
//To copy the selection to another bitmap for processing

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Dagan HooverDeveloperCommented:
@rfwoolf: Me likey
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