How can i merge this purple color marked line and remove the line outside of green marked area ?

After canny edge detection i got this following image. but how can I merge this purple marked line so that other lines will not be effected. and i also want to remove the line outside of green area. how can i do that ?

[ Raw Image]

[marked Image]

Answer 1

[Image Analyst]

See attached solution.

For linking the bottom lines, you can look at edge linking http://www.peterkovesi.com/matlabfns/#edgelink

Or you could try to do a cluster analysis on the lines and find common y values. Like if you knew there were 9 lines, you could use kmeans to get the centroids in the y direction and then use bwmorph(binaryImage, 'endpoints') to get the endpoints of all the line segments and then use imline() to burn a line connecting endpoints to the closest endpoint of another line in the sane y zone. I don't have code for that but it's pretty straightforward so try it.

[sufian ahmed]

i already tried edge link. but it not works. can u please check it.

[Image Analyst]

You forgot to attach it. I'll check again tomorrow.

[sufian ahmed]

i just tried the edgelink code, link provided by u. please if u can send me a demo code so that this line merges.

[Image Analyst]

I did not provide any edge linking code. Re-reads the last two paragraphs of my answer. In the last paragraph I outlined an approach you might take. In the other one I said

*"For linking the bottom lines, you can look at edge linking http://www.peterkovesi.com/matlabfns/#edgelink"*

Note that there was a link to someone else's web site which has code that you can adapt to your program and situation.

[sufian ahmed]

yes i told about this code.there is an edge-link code in u r provided link. I tried it. but it not works. If u can please provide me a code which will works to merge line

[Image Analyst]

Sorry, I don't have any right now to give you. I'd have to try the approach I outlined, or use Peter's code, and you can do that as well as I can.

[sufian ahmed]

ok i am trying. If u have free time. please try it :)

[Image Analyst]

Do you have the Statistics and Machine Learning Toolbox? It's a little easier if you do.

[sufian ahmed]

nope. i have not.