Edge Detection, Matlab Vision System Toolbox -

i have several images need find edge. have tried following vision.edgedetector system object in matlab, , example give here: http://www.mathworks.com/help/vision/ref/vision.edgedetectorclass.html

they give example

    hedge = vision.edgedetector;     hcsc = vision.colorspaceconverter('conversion','rbg intensity')     hidtypeconv = vision.imagedatatypeconverter('outputdatatype',single');     img = step(hcsc, imread('picture.png'))     img1 = step(hidtypeconv, ing);     edge = step(hedge,img1);     imshow(edges); 

which have followed in code.

however code doesn't produce edges like, seems though matlab can pick on half of edges in entire image. there different approach can take finding edges, or way improve upon vision.edgedetector object in matlab?

by default hedge = vision.edgedetector has threshold value of 20. try changing hedge = vision.edgedetector('threshold',value) , play value see value works out best you.