Showing papers by "Hellenic Military Academy published in 1996"
23 Oct 1996
TL;DR: This approach to off-line optical character recognition for hand-written or printed characters using for feature extraction and classification biorthogonal discrete wavelet transform achieves great recognition accuracy and font insensitivity requiring only a small training set of characters.
Abstract: We present an approach to off-line optical character recognition for hand-written or printed characters using for feature extraction and classification biorthogonal discrete wavelet transform. Our aim is to optimize character recognition methods independently of printing styles, writing styles and fonts used. Characters are identified with their contours, thus characterized from their curvature function. Curvature function is used for feature extraction while classification is accomplished by LVQ algorithms. This method achieves great recognition accuracy and font insensitivity requiring only a small training set of characters.
13 citations
23 Oct 1996
TL;DR: In this paper, the authors examined classes of unitary operators of L2(R) contained in the commutant of the shift operator, such that for any pari of multiresolution analyses of L 2(R), there exists a unitary operator in one of these classes, which maps all the scaling functions of the first multiiresolution analysis to the scaling function of the other.
Abstract: This paper examines classes of unitary operators of L2(R) contained in the commutant of the shift operator, such that for any pari of multiresolution analyses of L2(R) there exists a unitary operator in one of these classes, which maps all the scaling functions of the first multiresolution analysis to scaling functions of the other. We use these unitary operators to provide an interesting class of scaling functions. We show that the Dai-Larson unitary parameterization of orthonormal wavelets is not suitable for the study of scaling functions. These operators give an interesting relation between low-pass filters corresponding to scaling functions, which is implemented by a special class of unitary low-pass filters corresponding to scaling functions, which is implemented by a special class of unitary operators acting on L2([ -(pi) , (pi) ]), which we characterize. Using this characterization we recapture Daubechies' orthonormal wavelets by passing the spectral factorization process.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
2 citations