Expertomica Fishgui: comparison of fish skin colour

Authors

  • J. Urban,

    Corresponding author
    • University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, School of Complex Systemsm (former Institute of Physical Biology), Nové Hrady, Czech Republic
    Search for more papers by this author
  • D. Štys,

    1. University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, School of Complex Systemsm (former Institute of Physical Biology), Nové Hrady, Czech Republic
    Search for more papers by this author
  • M. Sergejevová,

    1. University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, School of Complex Systemsm (former Institute of Physical Biology), Nové Hrady, Czech Republic
    Search for more papers by this author
  • J. Masojídek

    1. University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, School of Complex Systemsm (former Institute of Physical Biology), Nové Hrady, Czech Republic
    2. Laboratory of Algal Biotechnology, Institute of Microbiology, Academy of Sciences, Třeboň, Czech Republic
    Search for more papers by this author

Author's address: Jan Urban, University of South Bohemia in České Budějovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, School of Complex Systems, (former Institute of Physical Biology), Zámek 136, CZ-373 33 Nové Hrady, Czech Republic.

E-mail: urbanj@frov.jcu.cz

Summary

The colour hue and saturation of the fish skin are important factors in fish breeding, reflecting the momentary physiological status of the fish. Algorithms evaluating fish colour were created in the MATLAB environment and compiled in the stand-alone application, Expertomica Fishgui. Fish groups fed on several diets (varying in carotenoid supplements) were compared as concerns image analysis methods on colour changes. Images were processed and evaluated to locate body positions, areas and colour saturation. Conversion from the Red-Green-Blue (RGB) colour space to chromatic colours was carried out to reduce the colour space. The threshold of skin chromatic colour was set on basis of the chromatic histograms using Otsu automatic bimodal segmentation. The average colour was calculated through all pixels of the selected area in the original image and through all images of the group. Colour conversion to the Hue-Saturation-Value (HSV) colour space was also carried out. Relative deviation between the saturation of samples in the control and the experimental groups provided a means of judgement. The dominant wavelength was also determined.

Ancillary