Two Approaches to Colour Management in Video Applications

Colour management in video applications includes conversion of colour space during transmission, as well as possible implementations of the assessment and measurement colour rendering fidelity of reproduced images. Colour management is usually based on the use the space of perceived colours formed at the input of the processing system using colour appearance model. There are two possible modes of colour appearance models. The first one is an approach based on the use of adaptive colour appearance models CIECAM02 and CAM16, most fully representing the colour appearance mechanism, but being conditionally uniform to the data on threshold colour discrimination and to data related to large colour differences. The second one is an approach based on the use of a geodesic model of colour appearance, which allows reproducing data on threshold colour differences with a relatively high degree of accuracy. Since for real models of colour appearance, the scatter of colour difference ellipsoids parameters vary with the parts of the diagram, it is important to have an integral and especially individual assessments in separate parts of the diagram. This can create prospects for better colour management. The paper presents the results of mathematical modeling and evaluation of two approaches, allowing quantitatively to assess the correlation of colour management quality associated with ideas about the accuracy of appearance assessment for small and large colour differences. It is supposed to introduce an additional data processing algorithm for both approaches, which allows to correct colour tone appearance errors in the blue region, as well as to adjust the lightness appearance characteristic so that both models, which is suitable for estimating the amount of colour rendering for HDR systems.