Method for recognizing print hand Arabic alphabets based on boundary characteristic

Abstract

The invention provides a print-form Arabic alphabet identification method based on boundary characteristic, wherein the upside, downside, left and right boundaries is regarded as a wave, each boundary is regarded as an assembly of a series of wave elements, and the following boundary characteristics are extracted therefrom: the number of the component wave, the number of the zero line, the length of the first zero line in the right boundary, the length of the first zero line in the downside boundary, the length of the longest zero line in the upside boundary, the length of the longest zero line in the right boundary, the length of the longest zero line in the upside boundary, the length of the longest zero line in the downside boundary and the number of the positive line in the upside boundary, moreover, the height width ratio of the alphabets and the alphabet auxiliary part are involved as the identification characteristics, finally, each print-form Arabic alphabet is identified by using four decision trees according to the four kinds of formats of the alphabets-the independent, the beginning, the middle and the end.

Description

(1) Technical field [0001] The invention relates to an optical character recognition method, in particular to a printed Arabic letter recognition method. (2) Background technology [0002] Among various languages ​​and characters, Arabic is one of the most widely used characters. Including the letter Lam-Alif, there are 29 Arabic alphabets. Simply put, the Arabic alphabet has the following characteristics: [0003] 1. Each Arabic letter has 2 to 4 different forms according to different positions in the word, which are independent, beginning, middle and end forms; [0004] 2. There are no vowels in Arabic, and vowels are reflected by marking auxiliary characters called "moving symbols" on consonants. In Arabic, there are two "movements" for vowels, namely Hamaza and Madda; [0005] 3. The letters Lam and the letters Alif can be connected together to form a new letter Lam-Alif; [0006] 4. The width of the letters is not equal, not only the width of different letters may ...

AI Technical Summary

Problems solved by technology

[0004] 2. There are no vowels in Arabic, and vowels are reflected by marking auxiliary characters called "moving symbols" on consonants

[0006] 4. The width of the letters is not equal, not only the width of different letters may be different, but also the four forms of a certain letter are not equal in width;

Among these methods, although the recognition methods based on image density and moment-invariant features are relatively simple, the algorithm speed is slow, and these methods do not make full use of the rich shape features of Arabic letters; the recognition method based on primitive features requires a refinement process, Its recognition speed is slow, and at the same time, due to the complex structure of Arabic letters, there will be breaks, burrs and other phenomena during the thinning process, resulting in a low recognition rate of this method

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