Grab the page edge in picture

In a photograph taken with the camera, shot from the corner of the page you can do to cut as selected and screened. I want to do this for Windows Forms.
The sample application https://play.google.com/store/apps/deta ... camscanner
https://play.google.com/store/apps/deta ... officelens
The sample application https://play.google.com/store/apps/deta ... camscanner
https://play.google.com/store/apps/deta ... officelens