I need to extract a vector of features from an image of characters. Features are:
1. Hu moment
2. Number of dots and their position
The coordinates of the four corners of the main body of characters are used to determine the position of the dots:
a) the label matrices of image objects are computed based on 8-connectivity neighborhood (the label matrix of an object is a vector of labeled pixel coordinates );
b)then, the four coordinates of the bounding box are computed to determine the position of the dot relative to the main character body.
3. Number of holes
The Euler number can be used to find the number of holes in a character. The Euler number is a scalar equal to the number of objects in the image minus the number of holes in those objects. The Euler number is computed based on the number of objects (NOB) in the image of a character as extracted by using label matrices.