Abstract

Performance of multispectral devices in recovering spectral data has been intensively investigated in some applications, as in spectral characterization of art paintings, but has received little attention in the context of spectral characterization of natural illumination. This study investigated the quality of the spectral estimation of daylight-type illuminants using a commercial digital CCD camera and a set of broadband colored filters. Several recovery algorithms that did not need information about spectral sensitivities of the camera sensors nor eigenvectors to describe the spectra were tested. Tests were carried out both with virtual data, using simulated camera responses, and real data obtained from real measurements. It was found that it is possible to recover daylight spectra with high spectral and colorimetric accuracy with a reduced number of three to nine spectral bands.

© 2005 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. F. H. Imai, R. Berns, “Spectral estimation using trichromatic digital cameras,” in International Symposium on Multispectral Imaging and Color Reproduction for Digital Archives (Society of Multispectral Imaging of Japan, 1999), pp. 42–49.
  2. F. H. Imai, R. Berns, D-Y. Tzeng, “A comparative analysis of spectral reflectance estimated in various spaces using a trichromatic camera system,” J. Imaging Sci. Technol. 44, 280–371 (2000).
  3. D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
    [CrossRef]
  4. J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
    [CrossRef]
  5. B. Hill, “(R)Evolution of color imaging systems,” in Proceedings of the Second European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2004), pp. 473–479.
  6. F. H. Imai, R. S. Berns, “Spectral estimation of oil paints using multi-filter trichromatic imaging,” in Proceedings of the 9th Congress of the International Colour Association (Proc. SPIE4421, 504–507 (2002).
    [CrossRef]
  7. Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
    [CrossRef]
  8. R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.
  9. S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
    [CrossRef]
  10. J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
    [CrossRef]
  11. J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
    [CrossRef]
  12. J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
    [CrossRef]
  13. D. Conahh, S. Westland, M. G. A. Thompson, “Optimization of a multispectral imaging system,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 619–622.
  14. C.-C. Chiao, T. W. Cronin, D. Osorio, “Color signals in natural scenes: characteristics of reflectance spectra and effects of natural illuminants,” J. Opt. Soc. Am. A 17, 218–224 (2000).
    [CrossRef]
  15. C.-C. Chiao, D. Osorio, M. Vorobyev, T. W. Cronin, “Characterization of natural illuminants in forests and the use of digital video data to reconstruct illuminant spectra,” J. Opt. Soc. Am. A 17, 1713–1721 (2000).
    [CrossRef]
  16. ColorChecker Chart from GretagMacbeth Ltd. (“GMB”) (2004).
  17. L. T. Maloney, B. Wandell, “Color constancy: a method for recovering surface spectral reflectance,” J. Opt. Soc. Am. A 3, 23–33 (1986).
    [CrossRef]
  18. F. H. Imai, M. R. Rosen, R. S. Berns, “Comparative study of metrics for spectral match quality,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 492–496.
  19. M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).
  20. G. Finlayson, “Spectral sharpening: what is it and why is it important,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 230–235.
  21. National Institute of Standards and Technology (NIST). http://physics.nist.gov/Divisions/Div844/Newrad/abstracts/NadalPoster.htm .
  22. M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
    [CrossRef] [PubMed]

2005 (1)

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

2004 (2)

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

ColorChecker Chart from GretagMacbeth Ltd. (“GMB”) (2004).

2002 (2)

S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
[CrossRef]

J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
[CrossRef]

2001 (3)

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
[CrossRef]

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

2000 (3)

1997 (1)

J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
[CrossRef]

1994 (1)

M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).

1986 (1)

L. T. Maloney, B. Wandell, “Color constancy: a method for recovering surface spectral reflectance,” J. Opt. Soc. Am. A 3, 23–33 (1986).
[CrossRef]

Berns, R.

F. H. Imai, R. Berns, D-Y. Tzeng, “A comparative analysis of spectral reflectance estimated in various spaces using a trichromatic camera system,” J. Imaging Sci. Technol. 44, 280–371 (2000).

F. H. Imai, R. Berns, “Spectral estimation using trichromatic digital cameras,” in International Symposium on Multispectral Imaging and Color Reproduction for Digital Archives (Society of Multispectral Imaging of Japan, 1999), pp. 42–49.

Berns, R. S.

F. H. Imai, M. R. Rosen, R. S. Berns, “Comparative study of metrics for spectral match quality,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 492–496.

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

F. H. Imai, R. S. Berns, “Spectral estimation of oil paints using multi-filter trichromatic imaging,” in Proceedings of the 9th Congress of the International Colour Association (Proc. SPIE4421, 504–507 (2002).
[CrossRef]

Brettel, H.

J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
[CrossRef]

Chiao, C.-C.

Conahh, D.

D. Conahh, S. Westland, M. G. A. Thompson, “Optimization of a multispectral imaging system,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 619–622.

Connah, D.

D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
[CrossRef]

Cronin, T. W.

Day, D. C.

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

Day, E. A.

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

Ferreira, F. P.

S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
[CrossRef]

Finlayson, G.

G. Finlayson, “Spectral sharpening: what is it and why is it important,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 230–235.

Foster, D. H.

S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
[CrossRef]

García-Beltrán, A.

J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
[CrossRef]

Gershon, R.

M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).

Hardeberg, J.

J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
[CrossRef]

Hernández-Andrés, J.

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
[CrossRef]

Hill, B.

B. Hill, “(R)Evolution of color imaging systems,” in Proceedings of the Second European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2004), pp. 473–479.

Imai, F. H.

F. H. Imai, R. Berns, D-Y. Tzeng, “A comparative analysis of spectral reflectance estimated in various spaces using a trichromatic camera system,” J. Imaging Sci. Technol. 44, 280–371 (2000).

F. H. Imai, R. S. Berns, “Spectral estimation of oil paints using multi-filter trichromatic imaging,” in Proceedings of the 9th Congress of the International Colour Association (Proc. SPIE4421, 504–507 (2002).
[CrossRef]

F. H. Imai, R. Berns, “Spectral estimation using trichromatic digital cameras,” in International Symposium on Multispectral Imaging and Color Reproduction for Digital Archives (Society of Multispectral Imaging of Japan, 1999), pp. 42–49.

F. H. Imai, M. R. Rosen, R. S. Berns, “Comparative study of metrics for spectral match quality,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 492–496.

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

Iwan, L. S.

M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).

Komiya, Y.

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Lee, R. L.

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

López-Álvarez, M. A.

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

Maloney, L. T.

L. T. Maloney, B. Wandell, “Color constancy: a method for recovering surface spectral reflectance,” J. Opt. Soc. Am. A 3, 23–33 (1986).
[CrossRef]

Murakami, Y.

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Nascimento, S. M. C.

S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
[CrossRef]

Nieves, J. L.

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

Obi, T.

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Ohyama, N.

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Osorio, D.

Romero, J.

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
[CrossRef]

Rosen, M. R.

F. H. Imai, M. R. Rosen, R. S. Berns, “Comparative study of metrics for spectral match quality,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 492–496.

Schmitt, F.

J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
[CrossRef]

Taplin, L. A.

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

Thompson, M. G. A.

D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
[CrossRef]

D. Conahh, S. Westland, M. G. A. Thompson, “Optimization of a multispectral imaging system,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 619–622.

Tzeng, D-Y.

F. H. Imai, R. Berns, D-Y. Tzeng, “A comparative analysis of spectral reflectance estimated in various spaces using a trichromatic camera system,” J. Imaging Sci. Technol. 44, 280–371 (2000).

Valero, E.

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

Vorobyev, M.

Vrhel, M. J.

M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).

Wandell, B.

L. T. Maloney, B. Wandell, “Color constancy: a method for recovering surface spectral reflectance,” J. Opt. Soc. Am. A 3, 23–33 (1986).
[CrossRef]

Westland, S.

D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
[CrossRef]

D. Conahh, S. Westland, M. G. A. Thompson, “Optimization of a multispectral imaging system,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 619–622.

Yamaguchi, M.

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Appl. Opt. (1)

M. A. López-Álvarez, J. Hernández-Andrés, J. Romero, R. L. Lee, “Designing a practical system for spectral imaging of skylight,” Appl. Opt. 44, 5688–5695 (2005).
[CrossRef] [PubMed]

Color Technol. (1)

D. Connah, S. Westland, M. G. A. Thompson, “Recovering spectral information using digital camera systems,” Color Technol. 117, 309–312 (2001).
[CrossRef]

Color Res. Appl. (1)

M. J. Vrhel, R. Gershon, L. S. Iwan, “Measurement and analysis of object reflectance spectra,” Color Res. Appl. 19, 4–9 (1994).

ColorChecker Chart from GretagMacbeth Ltd. (“GMB”) (1)

ColorChecker Chart from GretagMacbeth Ltd. (“GMB”) (2004).

J. Opt. Soc. Am. A (1)

L. T. Maloney, B. Wandell, “Color constancy: a method for recovering surface spectral reflectance,” J. Opt. Soc. Am. A 3, 23–33 (1986).
[CrossRef]

J. Imaging Sci. Technol. (1)

F. H. Imai, R. Berns, D-Y. Tzeng, “A comparative analysis of spectral reflectance estimated in various spaces using a trichromatic camera system,” J. Imaging Sci. Technol. 44, 280–371 (2000).

J. Opt. Soc. Am. A (1)

J. Romero, A. García-Beltrán, J. Hernández-Andrés, “Linear bases for representation of natural and artificial illuminants,” J. Opt. Soc. Am. A 14, 1007–1014 (1997).
[CrossRef]

J. Opt. Soc. Am. A (3)

J. Hernández-Andrés, J. Romero, J. L. Nieves, R. L. Lee, “Color and spectral analysis of daylight in southern Europe,” J. Opt. Soc. Am. A 18, 1325–1335 (2001).
[CrossRef]

J. Hernández-Andrés, J. L. Nieves, E. Valero, J. Romero, “Spectral-daylight recovery by use of only a few sensors,” J. Opt. Soc. Am. A 21, 13–23 (2004).
[CrossRef]

S. M. C. Nascimento, F. P. Ferreira, D. H. Foster, “Statistics of spatial cone-excitation ratios in natural scenes,” J. Opt. Soc. Am. A 19, 1484–1490 (2002).
[CrossRef]

J. Opt. Soc. Am. A (2)

Opt. Commun. (1)

Y. Murakami, T. Obi, M. Yamaguchi, N. Ohyama, Y. Komiya, “Spectral reflectance estimation from multi-band image using color chart,” Opt. Commun. 188, 47–54 (2001).
[CrossRef]

Opt. Eng. (1)

J. Hardeberg, F. Schmitt, H. Brettel, “Multispectral color image capture using a liquid crystal tunable filter,” Opt. Eng. 41, 2532–2548 (2002).
[CrossRef]

Other (8)

B. Hill, “(R)Evolution of color imaging systems,” in Proceedings of the Second European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2004), pp. 473–479.

F. H. Imai, R. S. Berns, “Spectral estimation of oil paints using multi-filter trichromatic imaging,” in Proceedings of the 9th Congress of the International Colour Association (Proc. SPIE4421, 504–507 (2002).
[CrossRef]

R. S. Berns, L. A. Taplin, F. H. Imai, E. A. Day, D. C. Day, “Spectral imaging of Matisse’s Pot of Geraniums: a case study,” in Proceedings of Eleventh Color Imaging Conference: Color Science and Engineering,Systems, Technologies and Applications (IS&T, Springfield, 2003) pp. 149–153.

F. H. Imai, R. Berns, “Spectral estimation using trichromatic digital cameras,” in International Symposium on Multispectral Imaging and Color Reproduction for Digital Archives (Society of Multispectral Imaging of Japan, 1999), pp. 42–49.

D. Conahh, S. Westland, M. G. A. Thompson, “Optimization of a multispectral imaging system,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 619–622.

F. H. Imai, M. R. Rosen, R. S. Berns, “Comparative study of metrics for spectral match quality,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 492–496.

G. Finlayson, “Spectral sharpening: what is it and why is it important,” in Proceedings of the First European Conference on Colour in Graphics, Imaging and Vision (Society for Imaging Science and Technology, Springfield, Va., 2002), pp. 230–235.

National Institute of Standards and Technology (NIST). http://physics.nist.gov/Divisions/Div844/Newrad/abstracts/NadalPoster.htm .

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (6)

Fig. 1
Fig. 1

Spectral sensitivity functions of the Retiga 1300 digital CCD camera from 400 to 700 nm (sampled at 5 nm).

Fig. 2
Fig. 2

Spectral transmittance curves of the six color filters used for the simulated and for the experimental wide-band imaging SPD synthesis.

Fig. 3
Fig. 3

99th percentile for GFC (upper figure) and for CIELab units (lower figure) for the estimation algorithms tested for the camera without filter, k = 3, and for each of single colored filters, k = 6. Data obtained from the synthesis methods with the same number of sensors and eigenvector coefficients.

Fig. 4
Fig. 4

99th percentile for GFC (upper figure) and for CIELab units (lower figure) for the estimation algorithms and for the different sets of double colored filters used, k = 9. Data obtained from the synthesis methods with the same number of sensors and eigenvector coefficients.

Fig. 5
Fig. 5

Original daylight spectrum (solid curve) and recovered spectrum (dashed curve) using the direct pseudoinverse method with simulated digital counts and three, six, and nine sensors. Results are for the 99th percentile of the GFC, and the original SPDs correspond to sunset hours of a day.

Fig. 6
Fig. 6

Original daylight spectrum measured in Granada at noon (solid curve) and recovered spectrum (dashed curve) using the direct pseudoinverse method with three, six, and nine sensors and real measurements; results are for the 99th percentile of the CIELab units.

Tables (2)

Tables Icon

Table 1 Mean, Standard Deviation, and 99th Percentile Results Obtained for Simulated Digital Counts in Recovering 433 SPD Daylight Spectra

Tables Icon

Table 2 Mean, Standard Deviation, and 99th Percentile Results Obtained for Measured Digital Counts in Recovering 30 SPD Daylight Spectra

Equations (11)

Equations on this page are rendered with MathJax. Learn more.

ρ k = λ = 400 700 E ( λ ) r W ( λ ) Q k ( λ ) .
E ( λ ) = i = 1 m ɛ i V i ( λ ) ,
ρ = Λ · ɛ ,
Λ k i = λ V i ( λ ) r W ( λ ) Q k ( λ ) ,
ɛ i = E ( λ ) V i ( λ ) .
ɛ e = G · ρ ,
G = ɛ ρ T [ ρ · ρ T ] - 1 .
E e = V ( G · ρ ) .
error = E - F · ρ 2 ,
F = E · ρ T [ ρ · ρ T ] - 1 .
E e = E · ρ T [ ρ · ρ T ] - 1 ρ .

Metrics