Problems with syntax and implementation of houghlines

Hello everyone. This question is to continue with one of my previous queries

https://www.mathworks.com/matlabcentral/answers/710798-line-length-and-orientation-angle-of-two-or-more-intersecting-lines

I have 2048 binarized tif images which has some lines that intersect or collapse on one another. I have a MATLAB code with regionprops and it works fine when the lines are not collapsing or intersect. I want to replace regionprops with houghlines, and measure the the following properties of the lines in the images:

'centroid', 'Extrema', 'Orientation', 'MajorAxislength' that regionprops measures in general.

[Matt J]

I am unable to attach tif format files here.

Could you convert it, or post a screenshot of the image so that we have an idea of what it looks like?

What does it mean for a line to "collapse"?

[SS]

Hi, thanks for your prompt response. I have attached the screenshots of the images. As you can see in Pic1, the line elements in the yellow ellipse is actually one entity but there is some unfilled gap which makes them look like 2 different lines. I want to treat such cases as one line if the distance between the centroids is less than 100 pixels.

Thanks again.

Answer 1

[Pratyush Roy]

Hi,

The lines generated by the houghlines method has several properties.Here point1 and point2 represent the coordinates of the extrema points of the line segment and theta represent the orientation of the line. To obtain the centroid, one can take the mean of the point vectors point1 and point2. The axis length for the line can be assumed to the length of the line segment hich is equal to the absolute value of the difference between the point coordinates. To reduce the unfilled gap between the two filled lines, the "FillGap" Name-Value parameter can be changed with the minumum distance between the two lines so that they can be merged.

Hope this helps!