Canny algorithm in my project

In my project i have to detect blood cell edges. I found it canny algorithm is very much useful to detect edges. The Canny edge detection operator was developed by John F. Canny in 1986 and uses this multi-stage algorithm to detect a wide range of edges in images.
In my project i will give blood samples as input. The image is gray scaled and subjected to canny algorithm. There are various stages in this algorithm.

Noise Reduction:

This is the first stage of algorithm. In this staged we remove unwanted pixels in the image.It uses a first derivative of Gaussian filter. After applying this filter the image is converted into a slightly blurred image. This is the 5 X 5 Gaussian filter.

Finding the intensity gradient of the image:

An edge in an image may point in a variety of directions, so the Canny algorithm uses four filters to detect horizontal, vertical and diagonal edges in the blurred image.The edge detection operator (Roberts, Prewitt, Sobel for example) returns a value for the first derivative in the horizontal direction (Gy) and the vertical direction (Gx). From this the edge gradient and direction can be determined.The edge direction angle is rounded to one of four angles representing vertical, horizontal and the two diagonals.



Rest of stages in next post