How to recognize military ID numbers?

Question

Delphi

I'm trying to implement number recognition on a scan of a military ID, I can imagine the process as a whole:

1. Upload picture
   
2. Cut off all excess
   
3. Get rid of unwanted colors
   
4. Define area with number
   
5. Determine the angle of the inscription
   
6. Align it
   
7. Select numbers/letters
   
8. Recognize (:
   

At the moment, I have implemented part of the functionality, but I just can’t figure out how to select the very area I need .. (point 4). Tell me how to do it?
source

Answer 1

You need to use the Connected Component Labeling algorithm .
A few links on this topic:
Habr: Counting objects in a binary image. Part 1
Habr: Counting objects in a binary image. Part 2
Habr: Algorithms for filling images, popular and with ...
Wikipedia article
Source code

Answer 2

habrahabr.ru/post/116222 - There is a link to the source at the end.