Steps in Canny Edge Detector

Steps in Canny Edge Detector

1. Gaussian Smoothing

2.Find Derivatives of smoothed image

3.Magnitude and Orientation of gradient is found
4.Non-maximum Supression

Supresses the pixels that are not local maxima

if (gradient of a pixel is less than the gradient of its neighbouring pixels)

then  supress or make zero the intensities of that pixel.

else

maintain

5.Hysterisis Thresholding

If the gradient magnitude of a pixel is above hithres

  then it is edge pixel.

If the gradient magnitude of a pixel is below lowthres

  then it is not edge pixel.

If the gradient magnitude of a pixel is below hithres and above lowthres

  then check for connectedness.

      If connectedness of that pixel is high

       then it is edge pixel

      else

       not edge pixel

You can understand it better if u watch the below video
https://www.youtube.com/watch?v=lC-IrZsdTrw