Assessing a visual quality characteristic includes accessing and processing at least a first image or video signal and a second image or video signal and processing the accessed images or video signals. Based at least in part on processing the accessed images or video signals, a difference is measured between the processed at least first and second images or video signals. The visual quality characteristic relates to a magnitude of the measured difference between the processed at least first and second images or video signals. The at least first and second images or video signals include a high or visual dynamic range and/or a wide color gamut. The visual quality characteristic is assessed based, at least in part, on the measured difference.