Extension of a human visual system model for display simulation

In the context of medical display validation, a simulation chain has been developed to facilitate display design and image quality validation. One important part is the human visual observer model to quantify the quality perception of the simulated images. Since several years, multiple research groups are modeling the various aspects of human perception to integrate them in a complete Human Visual System (HVS) and developing visible image difference metrics. In our framework, the JNDmetrix is used. It reflects the human subjective assessment of images or video fidelity. Nevertheless, the system is limited and not suitable for our accurate simulations. There is a limitation to RGB 8 bits integer images and the model takes into account display parameters like gamma, black offset, ambient light... It needs to be extended. The solutions proposed to extend the HVS model are: precision enhancement to overcome the 8 bit limit, color space conversion between XYZ and RGB and adaptation to the display parameters. The preprocessing does not introduce any kind of perceived distortion caused for example by precision enhancement. With this extension the model is used in a daily basis in the display simulation chain.