Methods and systems for generating an image quality metric are described. A reference and a test image are first converted to the ITP color space. After calculating difference images ΔI, ΔT, and ΔP, using the color channels of the two images, the difference images are convolved with low pass filters, one for the I channel and one for the chroma channels (I or P). The image quality metric is computed as a function of the sum of squares of filtered ΔI, ΔT, and ΔP values. The chroma low-pass filter is designed to maximize matching the image quality metric with subjective results.