Binarization Algorithm of Passport Image Based on Global Iterative Threshold and Local Analysis

A global binarization methods of the passport image based on global iterative threshold and local analysis is put forward in this paper after several binarization algorithms of document image are deeply studied according to the characteristics that passport image documents are obviously affected by the complex image background and the shading grid security-lines. Model of the method is simple, and easy to implement, can filter out noise availably. The character strokes can segmented from the background clearly.