Shape Recognition, hough transform

Hi All:

I seen more examples to recognize line/circles/ellipse using Hough transform, but i didnt find examples for square or rectangles. Can anyone help me on this?

thanks.

Answer 1

[Geoff]

You could look at this code on FileExchange, which appears to support triangles and squares:

http://www.mathworks.com/matlabcentral/fileexchange/9275-simple-shape-detection-using-hough-transform

It's been years since I did anything with the hough transform, but from memory if you want to find rectangles (or indeed ellipses) you need to search a range of possible width/height ratios or hard-code the width/height ratio that you are looking for. I think even with regular geometry like squares and circles you still need to specify a width/radius.

[Pugazhendhi]

Thanks for the reply. What you assumed is correct. I am looking for a code which should detect the shapes like square/rectangle and plot on the image. I found few codes for hough transform and I didnt get the method/way to detect shapes.

Answer 2

[Andri Pranata]

hi pugazhendi :) you said you've seed code to detect ellipse? could you give me the code? i need that code for my research, thankyou :)