1. A method of measuring a quality of a test video stream, the method comprising: measuring a content richness fidelity feature of the test video stream based on occurrences of color values in image frames of the test video stream; measuring a block-fidelity, feature of the test video stream based on distortion at block-boundaries in the image frames of the test video stream; measuring a distortion-invisibility feature of the test video stream based on distortion at pixels of the image frames of the test video stream; and determining a quality rating for the test video stream based on the content richness fidelity feature, the block-fidelity feature and the distortion-invisibility feature measured.