Now, the histogram is created for each fenced area. Simply, Ink pixels is counted for each member of the area, and the result is placed in the table.

The first group of three histograms is for three horizontal parts (upper, middle, and bottom) of the first digit. Then follows left, middle and right vertical areas. At last, the slant area is also counted and histogram created. This slant area histogram is useful in recognizing numbers 4 and 7, which have lines that cover that area and the peak in that histogram should be detected.



    Back to projects 
0. Home
H. Hardware
L. Lighting
1. Frame fetch
2. Ball locate
3. Stretching
4. Unsharp mask
5. Component selection
6. Holes and scratches
7. Component shrink
8. Invert selection
9. Component list
10. Select best circle
11. Angle detection
12. Rotate selected
13. Select broad lines
14. Selected components list
15. Components scaling
16. Histogram
17. MSE and voting
C. Conclusion