Identify shapes from images

Hello, I am working on my MSc project where I need to identify shapes from line-drawings. I need to store the location and co-ordinates of these shapes, so I can refer each object that make up the image as a separate entity . Will it be possible to break down each entity? The main concern is to identify the shapes in the image. What methods can be used? Thanks

Answer 1

[Majid Al-Sirafi]

i think you can use image segmentation methods

Answer 2

[Image Analyst]

See my image segmentation tutorial: http://www.mathworks.com/matlabcentral/fileexchange/?term=authorid%3A31862

You can often use the Perimeter^2 / (4*pi*Area) as a metric to distinguish shapes from one another. That metric will be 1 for a circle and have different ranges for rectangles, triangles, etc. You can also use the majoraxis, minor axis, eccentricity, etc. to try to better define the shapes you're interested in. Basically you make up a "feature vector" which is a list of values for those various parameters that your different objects have. So the feature vector for triangles would have different values than a feature vector for discs.