Use of Pseudo 2D Hidden Markov Models for handwritten digit recognition
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Abstract
In this article, we present a new method for digit recognition
manuscripts which solves the problems of the multiplicity of the shape of handwritten figures
thus the problems of inclination and size. The characteristics of handwritten numbers are
used and this by exploiting the elastic structure of Hidden Markov Models.
Independence in size and inclination is a desired property for a system of
robust recognition. One solution to achieve this goal is to implement a
size normalization and tilt correction in the 1D HMM approach. We propose
a PHMM architecture including a vertical model of superstates and models
horizontal, one per super state. We will distinguish between the main model composed of
superstates and secondary models associated with superstates. For an image, the model
main will do the analysis according to one direction (the vertical direction) and the secondary models
will do it along the other axis. Our approach allows recognition of handwritten digits
inclined. Experiments on a large number base show results
promising with tolerable execution times.
Article Details
References
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