How to get the edge coordinates of the image?

Question

I posted a question about how you click on the image represented in the parent image. How can I crop an image using C # I found the edge of the image using one of the online algorithms, now I need to get the coordinates of the angles. How can I get the angular coordinates so that I can get the image from my parent?

The image is taken using the camera and contains the image of the document. I need to find this document and cut it from the parent image.

Answer 1

In the other message you linked , a number of angle determination algorithms were included. I experimented with AForge filters to determine the Hough angle or linear transform in conjunction with a canny edge detector to highlight the edges of the image.