The linearization of the relationship between scene luminance and digital camera output levels
Authors: Czech Eugeniusz , Czyżewski Dariusz 
Published: May 2021

This paper presents the results of linearity testing of the integrated image sensor of a CCD-equipped digital camera. The study demonstrated the lack of linearity of the characteristics of the sensor when scaling with the luminance standard signal. In the course of the research the function approximated by the fifth-degree polynomial was determined. After the appropriate transformation, this function would enable the linearization of the signal from the studied image sensor. The study demonstrated the possibility of linearizing the signal of integrated image sensors for correct luminance measurements. Thus, the possibility of reducing the nonlinearity error of integrated image sensors was discussed. Full Text: PDF ReferencesT. Tashiro, S. Kawanobe, T. Kimura-Minoda, S. Kohko, T. Ishikawa, and M. Ayama, "Discomfort glare for white LED light sources with different spatial arrangements," Lighting Research and Technology, vol. 47, no. 3, pp. 316-337, 2015, doi: 10.1177/1477153514532122. 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