Optical Pattern Recognition

This has been one of his main fields of interest. We have built optical correlators with liquid crystal panels. He has proposed methods to design filters for pattern recognition by correlation, and the use of a filter bank to perform difficult tasks. We have studied the problem of the recognition of objects in scenes degraded by defocus or movements. One of the main contributions is the introduction of the color information in the pattern recognition process. We have proposed the method based on considering the color images as 3D images. In this way the Fourier methods and correlation can be extended to these functions. We have also found a relation between the Fourier transform along the color axis and the colorimetric characteristics: hue, saturation and brightness. They have proposed methods to implement these operations in optical correlators.


  1. J. CamposMoreno, I.Nicolás, J., and Yzuel, M. J.“Uses of spatial light modulators for colour optical processing”, Proceedings SPIE, vol. 8833, pp. 88330A-1-10, 2013.
  2. J. MazzaferriCampos, J.Escalera, J. C.Sheppard, C. J. R., and Ledesma, S.“Edge detector tolerant to object defocusing”, Optics Communications, vol. 283, pp. 3639 - 3645, 2010.
  3. J. A. DavisTuvey, S. C.López-Coronado, O.Campos, J.Yzuel, M. J., and Iemmi, C.“Tailoring the depth of focus for optical imaging systems using a Fourier transform approach”, Opt. Lett., vol. 32, pp. 844–846, 2007.
  4. J. NicolásIemmi, C.Campos, J., and Yzuel, M. J.“Encoding 3D correlation in an optical processor”, Optics Communications, vol. 256, pp. 279 - 287, 2005.
  5. O. GualdrónDavis, J. A.Nicolás, J.Campos, J., and Yzuel, M. J.“Complex encoding of rotation-invariant filters onto a single phase-only spatial light modulator”, Appl. Opt., vol. 42, pp. 1973–1980, 2003.
  6. A. MárquezBeléndez, A.Campos, J.Pascual, I.Yzuel, M. J.Fimia, A., and Neipp, C.“Low spatial frequency characterization of holographic recording materials applied to correlation”, Proc. SPIE, vol. 4829, pp. 791-792, 2003.
  7. A. VargasCampos, J.Martin, S. C., and Vera, N.“Multichannel analysis to obtain invariant pattern recognition with defocused images”, Proc. SPIE, vol. 4829, pp. 247-248, 2003.
  8. J. BarbeCampos, J.Nicolás, J., and Iemmi, C.“Multichannel optical correlator for texture classification”, Optical Engineering, vol. 42, pp. 2062-2067, 2003.
  9. M. VillarrealIemmi, C., and Campos, J.“Parallel classification of multiple objects using a phase-only multichannel optical correlator”, Optical Engineering, vol. 42, pp. 2354-2361, 2003.
  10. J. NicolásMoreno, I.Campos, J., and Yzuel, M. J.“Phase-only filtering on the three-dimensional Fourier spectrum of color images”, Appl. Opt., vol. 42, pp. 1426–1433, 2003.
  11. O. GualdrónNicolás, J.Campos, J., and Yzuel, M. J.“Rotation invariant color pattern recognition by use of a three-dimensional Fourier transform”, Appl. Opt., vol. 42, pp. 1434–1440, 2003.
  12. A. AttalebAhouzi, E.Campos, J.Moreno, I., and Yzuel, M. J.“Optimization of the polychromatic discrimination capability in multichannel pattern recognition”, Optical Engineering, vol. 41, pp. 3250-3259, 2002.
  13. M. J. YzuelNicolás, J.Moreno, I., and Campos, J.“3D filter design for color pattern recognition”, Proc. SPIE, vol. 4471, pp. 34-42, 2001.
  14. A. VargasMartin, S. C.Figueroa, R.Campos, J., and Yzuel, M. J.“Invariant pattern recognition with defocused images”, Proc. SPIE, vol. 4419, pp. 608-611, 2001.
  15. M. VillarrealIemmi, C., and Campos, J.“Phase filter multiplexing for pattern recognition process”, Proc. SPIE, vol. 4419, pp. 616-619, 2001.
  16. J. NicolásIemmi, C.Campos, J., and Yzuel, M. J.“Real-time correlator with liquid crystal panels: modulation optimization”, Proc. SPIE, vol. 4419, pp. 604-607, 2001.
  17. J. NicolásYzuel, M. J., and Campos, J.“Colour pattern recognition by three-dimensional correlation”, Optics Communications, vol. 184, pp. 335 - 343, 2000.
  18. A. VargasCampos, J., and Navarro, R.“Invariant pattern recognition against defocus based on subband decomposition of the filter”, Optics Communications, vol. 185, pp. 33 - 40, 2000.
  19. A. MárquezBarbe, J.Yzuel, M. J., and Campos, J.“Optical correlator as a tool for physicists and engineers training in signal processing”, Proc. SPIE, vol. 3831, pp. 297-306, 2000.
  20. J. CamposLhostis, S., and Guillaume, M.“Optimal multichannel estimation of the location of a target with nonoverlapping noise”, J. Opt. Soc. Am. A, vol. 17, pp. 2140–2147, 2000.
  21. R. KasztelanicCampos, J., and Chalasinska-Macukow, K.“Shift-invariant optoelectronic associative memory by using a cascade of correlators”, Optical Engineering, vol. 39, pp. 993-1001, 2000.
  22. J. CamposYzuel, M. J.Moreno, I.Ahouzi, E.Márquez, A.López-Coronado, O., and Attaleb, A.“Adapting the input scene and the filter to the operating curves of the modulators in real-time correlators”, Proc. SPIE, vol. 3804, pp. 204-214, 1999.
  23. J. A. DavisCottrell, D. M.Campos, J.Yzuel, M. J., and Moreno, I.“Bessel function output from an optical correlator with a phase-only encoded inverse filter”, Appl. Opt., vol. 38, pp. 6709–6713, 1999.
  24. J. Barbe and Campos, J.“Image segmentation with a white light optical correlator”, Proc. SPIE, vol. 3749, pp. 775-776, 1999.
  25. S. LedesmaIemmi, C.Villarreal, M., and Campos, J.“Multichannel correlation by color multiplexing”, Optics Communications, vol. 166, pp. 173 - 180, 1999.
  26. M. J. YzuelCampos, J.Moreno, I.Ahouzi, E., and Attaleb, A.“Multichannel pattern recognition of color images”, Proc. SPIE, vol. 3904, pp. 216-227, 1999.
  27. M. J. YzuelCampos, J.Navarro, R.Ahouzi, E.Moreno, I.Vargas, A., and López-Coronado, O.“Optical architectures for real-time image processing and pattern recognition”, Proc. SPIE, vol. 3572, pp. 597-600, 1999.
  28. C. IemmiLedesma, S.Campos, J., and Villarreal, M.“Optical classification employing composed gray-level CGH filters”, Proc. SPIE, vol. 3749, pp. 209-210, 1999.
  29. A. VargasCampos, J.Iemmi, C.Ledesma, S., and Yzuel, M. J.“Optical codification for multiclass pattern recognition using a parallel correlator”, Optics Communications, vol. 162, pp. 121 - 129, 1999.
  30. M. GuillaumeCampos, J., and Lashin, V.“Pattern location estimation for multichannel images”, Optics Communications, vol. 165, pp. 107 - 117, 1999.
  31. A. VargasCampos, J.Yzuel, M. J.Iemmi, C., and Ledesma, S.“Use of the periodic structure of spatial light modulators for parallel pattern recognition”, in Proc. SPIE, vol. 3572, 1999, pp. 305-308.
  32. E. AhouziCampos, J., and Yzuel, M. J.“Binary amplitude phase-only filter with high multiobject discrimination capability”, Optical Engineering, vol. 37, pp. 2351-2358, 1998.
  33. O. López-CoronadoCampos, J.Moreno, I., and Yzuel, M. J.“Correlation enhancement by adapting the filter to in-situ measured operating curves of the SLMs”, Proc. SPIE, vol. 3490, pp. 445-448, 1998.
  34. R. KasztelanicChalasinska-Macukow, K., and Campos, J.“Correlation filters with carrier frequency for multiclass pattern recognition”, Proc. SPIE, vol. 3490, pp. 199-202, 1998.
  35. I. MorenoCampos, J.Yzuel, M. J., and Kober, V.“Implementation of bipolar real-valued input scenes in a real-time optical correlator: application to color pattern recognition”, Optical Engineering, vol. 37, pp. 144-150, 1998.
  36. L. P. YaroslavskyLópez-Coronado, O., and Campos, J.“Input-image homogenization as a method to improve a correlator's discrimination capability”, Opt. Lett., vol. 23, pp. 1129–1131, 1998.
  37. S. LedesmaIemmi, C.Campos, J., and Yzuel, M. J.“Joint transform correlator architecture with a single \{LCTV\} operating in phase-mostly mode”, Optics Communications, vol. 151, pp. 101 - 109, 1998.
  38. A. VargasCampos, J.Yzuel, M. J.Iemmi, C., and Ledesma, S.“One-step multichannel pattern recognition based on the pixelated structure of a spatial light modulator”, Appl. Opt., vol. 37, pp. 2063–2066, 1998.
  39. J. CamposLedesma, S.Iemmi, C., and Yzuel, M. J.“Pure phase correlation in a phase-only joint transform correlator”, Proc. SPIE, vol. 3490, pp. 492-495, 1998.
  40. H. J. CaulfieldMoreno, I.Campos, J., and Yzuel, M. J.“Coherent recognition of colored patterns”, Optics Communications, vol. 133, pp. 77 - 81, 1997.
  41. V. KoberLashin, V.Moreno, I.Campos, J.Yaroslavsky, L. P., and Yzuel, M. J.“Color component transformations for optical pattern recognition”, J. Opt. Soc. Am. A, vol. 14, pp. 2656–2669, 1997.
  42. I. MorenoAhouzi, E.Campos, J., and Yzuel, M. J.“Implementation of optimized binary amplitude phase-only filters in phase-only modulators”, Proc. SPIE, vol. 3101, pp. 146-155, 1997.
  43. M. GuillaumeRéfrégier, P.Campos, J., and Lashin, V.“Detection theory approach to multichannel pattern location”, Opt. Lett., vol. 22, pp. 1887–1889, 1997.
  44. I. MorenoAhouzi, E.Campos, J., and Yzuel, M. J.“Real-time binary-amplitude phase-only filters”, Appl. Opt., vol. 36, pp. 7428–7432, 1997.
  45. A. VargasCampos, J., and Navarro, R.“Application of the Gabor multiscale decomposition of an image to pattern recognition”, Proc. SPIE, vol. 2730, pp. 622-625, 1996.
  46. I. MorenoYaroslavsky, L. P.Yzuel, M. J.Kober, V.Lashin, V., and Campos, J.“Color pattern recognition with circular component whitening”, Opt. Lett., vol. 21, pp. 498–500, 1996.
  47. M. Montes‐UsateguiCampos, J.Sallent, J., and Juvells, I.“Complex sidelobe removal by a multichannel procedure”, Optical Engineering, vol. 35, pp. 514-524, 1996.
  48. S. BoschCampos, J.Montes-Usategui, M., and Sallent, J.“Design of correlation filters invariant to degradations characterizable by an optical transfer function”, Optics Communications, vol. 129, pp. 337 - 343, 1996.
  49. E. AhouziCampos, J.Kober, V., and Yzuel, M. J.“Design of phase-only filters with binary amplitude optimizing the discrimination: direct search or simulated annealing?”, Proc. SPIE, vol. 2730, pp. 51-54, 1996.
  50. K. StyczyńskiChalasinska-Macukow, K.Campos, J., and Yzuel, M. J.“Minimum mean square error filters for spatially non-overlapping phase target and input scene noise”, Optics Communications, vol. 127, pp. 325 - 333, 1996.
  51. I. MorenoKober, V.Lashin, V.Campos, J.Yaroslavsky, L. P., and Yzuel, M. J.“Whitening preprocessing of color components for pattern recognition”, Proc. SPIE, vol. 2730, pp. 617-621, 1996.
  52. K. StyczynskiCampos, J.Chalasinska-Macukow, K., and Yzuel, M. J.“Application of twisted nematic liquid crystal displays in optical correlation technics”, Proc. SPIE, vol. 2372, pp. 337-342, 1995.
  53. M. Montes-UsateguiCampos, J., and Juvells, I.“Computation of arbitrarily constrained synthetic discriminant functions”, Appl. Opt., vol. 34, pp. 3904–3914, 1995.
  54. M. J. YzuelMoreno, I.Corbalan-Fuertes, M.Ahouzi, E.Millán, M. S.Turon, F.Gorecki, C., and Campos, J.“Correlation methods in polychromatic objects recognition: application of lithographic filters”, Proc. SPIE, vol. 2363, pp. 200-210, 1995.
  55. V. KoberYaroslavsky, L. P.Campos, J., and Yzuel, M. J.“Improvement of light efficiency of the optimal filter for optical pattern recognition”, Proc. SPIE, vol. 2363, pp. 127-132, 1995.
  56. K. StyczynskiCampos, J.Yzuel, M. J., and Chalasinska-Macukow, K.“New arrangement for limited intensity invariance pattern recognition with high diffraction efficiency”, Optics Communications, vol. 118, pp. 193 - 198, 1995.
  57. J. GarciaCampos, J., and Ferreira, C.“Circular-harmonic minimum average correlation energy filter for color pattern recognition”, Appl. Opt., vol. 33, pp. 2180–2187, 1994.
  58. M. Montes-UsateguiCampos, J.Juvells, I., and Carnicer, A.“Computation of phase-only synthetic discriminant fubctions: a new algorithm”, Proc. SPIE, vol. 2297, pp. 52-58, 1994.
  59. F. TuronAhouzi, E.Campos, J.Chalasinska-Macukow, K., and Yzuel, M. J.“Nonlinearity effects in the pure phase correlation method in multiobject scenes”, Appl. Opt., vol. 33, pp. 2188–2191, 1994.
  60. V. KoberYaroslavsky, L. P.Campos, J., and Yzuel, M. J.“Optimal filter approximation by means of a phase-only filter with quantization”, Opt. Lett., vol. 19, pp. 978–980, 1994.
  61. E. AhouziCampos, J., and Yzuel, M. J.“Phase-only filter with improved discrimination”, Opt. Lett., vol. 19, pp. 1340–1342, 1994.
  62. C. GoreckiMoreno, I.Campos, J.Yzuel, M. J., and Chalasinska-Macukow, K.“Real-time quantized phase-only filters generation on Epson liquid crystal TV”, Proc. SPIE, vol. 2297, pp. 90-101, 1994.
  63. J. CamposStyczynski, K.Yzuel, M. J., and Chalasinska-Macukow, K.“Recognition of partially occluded objects by correlation methods”, Optics Communications, vol. 106, pp. 45 - 51, 1994.
  64. J. CamposAhouzi, E., and Yzuel, M. J.“Edge-extraction preprocessing in pattern recognition”, Proc. SPIE, vol. 1806, pp. 500-510, 1993.
  65. M. S. MillánYzuel, M. J.Campos, J., and Ferreira, C.“Different strategies in optical recognition of polychromatic images”, Appl. Opt., vol. 31, pp. 2560–2567, 1992.
  66. C. FerreiraMillán, M. S.Yzuel, M. J., and Campos, J.“Experimental results in color pattern recognition by multichannel matched filtering”, Optical Engineering, vol. 31, pp. 2231-2238, 1992.
  67. J. GarciaFerreira, C.Campos, J.Bosch, S.Millán, M. S., and Yzuel, M. J.“Multichannel rotation-invariant pattern recognition for polychromatic objects using circular harmonic filters”, Optics Communications, vol. 91, pp. 425 - 432, 1992.
  68. J. CamposTuron, F., and Yzuel, M. J.“Pattern recognition with quantized computer-generated filters”, Appl. Opt., vol. 31, pp. 3337–3343, 1992.
  69. J. CamposMillán, M. S.Yzuel, M. J., and Ferreira, C.“Color-invariant character recognition and character-background color identification by multichannel matched filter”, Proc. SPIE, vol. 1564, pp. 189-198, 1991.
  70. J. CamposBosch, S., and Sallent, J.“Optical pattern recognition in defocused images using correlation filters”, Optics Communications, vol. 82, pp. 370 - 379, 1991.
  71. S. VallmitjanaJuvells, I.Carnicer, A., and Campos, J.“Pattern detection using a modified composite filter with nonlinear joint transform correlator”, Proc. SPIE, vol. 1564, pp. 266-274, 1991.
  72. J. CamposBosch, S.Millán, M. S.Ferreira, C., and Yzuel, M. J.“Circular harmonic correlation filters for rotationally invariant color pattern recognition”, Proc. SPIE, vol. 1319, pp. 426-426, 1990.
  73. M. S. MillánCampos, J.Ferreira, C., and Yzuel, M. J.“Experimental multichannel recognition capability of polychromatic objects using optical correlators”, Proc. SPIE, vol. 1319, pp. 422-422, 1990.
  74. K. Chalasinska-MacukowTuron, F.Yzuel, M. J., and Campos, J.“Performance of the pure phase-only correlation method for pattern recognition”, Proc. SPIE, vol. 1347, pp. 262-273, 1990.
  75. J. CamposTuron, F.Yzuel, M. J., and Vallmitjana, S.“Phase-only filters codified with Burckhardt's method”, Appl. Opt., vol. 29, pp. 5232–5234, 1990.
  76. M. S. MillánCampos, J.Ferreira, C., and Yzuel, M. J.“Matched filter and phase only filter performance in colour image recognition”, Optics Communications, vol. 73, pp. 277 - 284, 1989.
  77. M. S. MillánCampos, J.Ferreira, C., and Yzuel, M. J.“Recognition Of Polychromatic Test By Multi-Channel Correlation Filtering”, Proc. SPIE, vol. 1134, pp. 126-133, 1989.
  78. S. VallmitjanaBertomeu, J.Juvells, I.Bosch, S., and Campos, J.“Optical edge detection by a holographic filtering method”, Optics Communications, vol. 68, pp. 334 - 338, 1988.
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