Crop Image in ASP.net

 I would like to have a function to upload image and crop the image into thumbnail ( The size for thumbnail is fixed.)

This is one of the example that i found:

http://michael.sivers.co.uk/post/2007/08/20/Crop-and-resize-an-image-in-ASPNET.aspx

But the problem is :

1. How can i let the user to determine which the area to crop it? ( like the gmail, user can select the area of image and crop  the selected area only)

 Besides, anybody know how to use the jQuery, JCrop?

Thanks.

 

 

 
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