Navegar

Colección

Datos Estadísticas

Conferencia

Mazzaferri, J.; Ledesma, S. "Wavelet coefficients thresholding method applied to the correlation of noisy scenes" (2004) RIAO/OPTILAS 2004: 5th Iberoamerican Meeting on Optics, and 8th Latin American Meeting on Optics, Lasers, and their Applications; ICO Regional Meeting. 5622(PART 2):617-621
La versión final de este artículo es de uso interno de la institución. El editor no permite incluir ninguna versión del artículo en el Repositorio
Consulte el artículo en la página del editor
Consulte la política de Acceso Abierto del editor

Abstract:

The distortion of a signal due to noise contamination can be overcome by using a decomposition of the signal in a base of wavelets. If the decomposition coefficients are small compared with the noise, the scene is dominated by the distortion. On the contrary, if they are bigger in absolute value, the signal is stronger that the noise. A way of reconstructing an image with a lower level of noise is accomplished neglecting the coefficients which values are lower than a threshold, and replacing them by zero. In this work we present a method that applies the thresholding of the wavelet coefficients in order to perform pattern recognition of noisy scenes. The method could be implemented in optical processing by using a Vander Lugt correlator architecture operating with liquid crystal displays. The function to be recognized is decomposed in sub-bands based on the Gabor decomposition, in the frequency plane. Hard thresholding is performed and the threshold is generated with accurate support functions in the filter plane. The criterion for the threshold selection is chosen to optimize the signal to noise ratio in the output plane. Numerical simulations results are shown and comparisons with other filters are made.

Registro:

Documento: Conferencia
Título:Wavelet coefficients thresholding method applied to the correlation of noisy scenes
Autor:Mazzaferri, J.; Ledesma, S.
Ciudad:Porlamar
Filiación:Depto. de Fis. J. J. Giambiagi, Fac. de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina
Palabras clave:Nonlinear optical signal processing; Optical correlators; Optical imaging processing; Pattern recognition and feature extraction; Nonlinear optical signal processing; Optical correlators; Optical imaginng processing; Pattern recognition and feature extraction; Distortion (waves); Feature extraction; Functions; Image analysis; Mathematical models; Nonlinear optics; Optical correlation; Signal processing; Signal to noise ratio; Spurious signal noise; Threshold elements; Wavelet transforms; Pattern recognition
Año:2004
Volumen:5622
Número:PART 2
Página de inicio:617
Página de fin:621
DOI: http://dx.doi.org/10.1117/12.591703
Título revista:RIAO/OPTILAS 2004: 5th Iberoamerican Meeting on Optics, and 8th Latin American Meeting on Optics, Lasers, and their Applications; ICO Regional Meeting
Título revista abreviado:Proc SPIE Int Soc Opt Eng
ISSN:0277786X
CODEN:PSISD
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_0277786X_v5622_nPART2_p617_Mazzaferri

Referencias:

  • Vander Lugt, A.B., Signal detection by complex filtering (1964) IEEE Trans. Inf. Theory, IT-10, pp. 139-145
  • Weaver, C.S., Goodman, J.W., A technique for optically convolving two functions (1966) App. Opt., 5, pp. 1248-1249
  • Yu, F.T.S., (1983) Optical Information Processing, , John Wiley & Sons, New York
  • Kumar, B.V.K.V., Bahri, Z., Phase-only filters with improved signal to noise ratio (1989) App. Opt., 28, pp. 250-257
  • Szu, H., Sheng, Y., Chen, J., Wavelet transform as a bank of matched filters (1992) App. Opt., 31, pp. 3267-3277
  • Maestre, R., García, J., Ferreira, C., Pattern recognition using sequential matched filtering of wavelet coefficients (1997) Opt. Comm., 133, pp. 401-414
  • Mazzaferri, J., Ledesma, S., Iemmi, C., Multiple feature extraction by using simultaneous wavelet transforms (2003) J. Opt. A, 5, pp. 425-431
  • Lin, L.-C., Cheng, C.-J., Pattern discrimination of joint transform correlator based on wavelet subband filtering (2004) Opt. Comm, 233, pp. 283-296A4 - Instituto Venezolano de Investigaciones Cientificas; Universidad Simon Bolivar; Universidad Central de Venezuela; Ministerio de ciencia y Tecnologia; Fundacion Polar

Citas:

---------- APA ----------
Mazzaferri, J. & Ledesma, S. (2004) . Wavelet coefficients thresholding method applied to the correlation of noisy scenes. RIAO/OPTILAS 2004: 5th Iberoamerican Meeting on Optics, and 8th Latin American Meeting on Optics, Lasers, and their Applications; ICO Regional Meeting, 5622(PART 2), 617-621.
http://dx.doi.org/10.1117/12.591703
---------- CHICAGO ----------
Mazzaferri, J., Ledesma, S. "Wavelet coefficients thresholding method applied to the correlation of noisy scenes" . RIAO/OPTILAS 2004: 5th Iberoamerican Meeting on Optics, and 8th Latin American Meeting on Optics, Lasers, and their Applications; ICO Regional Meeting 5622, no. PART 2 (2004) : 617-621.
http://dx.doi.org/10.1117/12.591703
---------- MLA ----------
Mazzaferri, J., Ledesma, S. "Wavelet coefficients thresholding method applied to the correlation of noisy scenes" . RIAO/OPTILAS 2004: 5th Iberoamerican Meeting on Optics, and 8th Latin American Meeting on Optics, Lasers, and their Applications; ICO Regional Meeting, vol. 5622, no. PART 2, 2004, pp. 617-621.
http://dx.doi.org/10.1117/12.591703
---------- VANCOUVER ----------
Mazzaferri, J., Ledesma, S. Wavelet coefficients thresholding method applied to the correlation of noisy scenes. Proc SPIE Int Soc Opt Eng. 2004;5622(PART 2):617-621.
http://dx.doi.org/10.1117/12.591703