Color constancy for visual compensation of projector displayed image

The color of a displayed image by a projector can be distorted by features of the device, the ambient light, the projection screen, and also the observer. This has raised the need to correct the image during the display to eliminate these effects and to ensure a constancy of the color appearances. In this paper, we propose models for controlling the appearance of the displayed image. We argue that depending on the target application, the computational color constancy can be specified at different steps of the formation scheme of the sensed image by a human. Based on that observation and the image formation models, we reformulate the problem of the color constancy and we show that the resulting transformations cannot be explained by von Kries theory. Two compensation algorithms are deduced. The first allows preserving the appearance of the original image, and it can be used for the constancy of the acquired image whatever the environment conditions. The second algorithm allows to simulate appearances of a sensed image in a specific conditions. It can be used for the compensation of the screen reflectance or to create special effects or the camouflage. In addition, we propose a complementary operation for the contrast compensation which is derived from the Weber's law. Experimental results show the merits of the proposed models and algorithms. Projectors become more proliferate and integrated in multiple areas. However, the quality of the displayed image can be adversely affected by the device used and the real viewing conditions. The displayed image under bright conditions may appear with washed colors and attenuated contrast. The appearance of an image captured under illuminant D65, will be also affected when it is perceived under another illuminant. The mismatch between the display environmental illuminant and the illuminant of the image acquisition may influence the perception of the image. In addition , the displayed image onto an ordinary surface will be affected, where its appearance will be modulated by the color and the geometry of the surface. The projector features could also affect the quality of the displayed image. The transfer function, and the embedded color signal processing influence the color generation. Moreover, the sensed image quality depends on the spectral abilities of the human visual system (HVS). As it is characterized by its nonlinear response to the intensity of the ambient light [1], this means that the perceived contrast of the image will be …