Method and apparatus for image signal normalisation

摘要

The present invention relates to an apparatus and method for normalisation of an image signal, particularly for use in perceptual video and still image quality measurement when the quality measurement is achieved by making a comparison between a reference signal and a decoded signal. The invention provides a method for normalising a decoded image signal in relation to a reference image signal to generate a normalised image signal comprising the steps of: generating a non-linear transformation vector in dependence upon at least one component of the decoded image signal and at least one component of the reference image signal; and applying said non-linear transformation vector to at least one component of the decoded image signal to generate a normalised image signal. Methods and apparatus for perceptual video and still image quality measurement using said method are also provided.