According to obtaining the binary i

According to obtaining the binary image, it is processed to retrieve contours by find contour function for binary image and to return the number of retrieved contours which stored in the chain format. The OpenCV library uses two methods to represent contours. The first method is called the Freeman method or the chain code. For any pixel all its neighbors with numbers from 0 to 7 can be enumerated. The 0-neighbor denotes the pixel on the right side, etc. As a sequence of 8-connected points, the border can be stored as the coordinates of the initial point, followed by codes (from 0 to 7) that specify the location of the next point relative to the current one.