algorithm - Detect quadrilateral from grayscale image -


i'm looking method detect quadrilateral based on grayscale images this.

enter image description here enter image description here

the actual solution i've made based on houghlines , has 2 problems:

  • as parametric method, small changes on input image gives me 2 different rectangles.
  • the outputs not precise borders of rectangle in input image thick.

enter image description here enter image description here

can recommend me method ? i'm looking @ this article seems slow method.


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