A Random Colour Test Pattern Generator for Objective Colour Artefact Assessment in Benchmarking Colour Image Codecs

Subjective and objective quality measures are required for monitoring image and video systems. The aim of this research was to develop a random colour test pattern generator for digital codec and video system evaluation that is analogous to the colour bar signal commonly used in analogue television broadcasting. This approach is capable of highlighting coding colour artefacts, and enables both subjective and objective evaluation. The effectiveness of the developed test pattern is demonstrated using a JPEG codec and a JPEG2000 codec. Three objective colour artefact metrics are proposed of which two have been linked to the conventional vectorscope used in analogue television systems and other one to the dominant component of colour, namely the hue. That artefact metric is known as coding hue bleed. This paper also presents a performance comparison between JPEG and JPEG2000 codec with respect to colour reproduction.