UC Berkeley

Color breakup is an artifact seen on displays that present colors sequentially. When the eye tracks a moving object on such a display, different colors land on different places on the retina, and this gives rise to visible color fringes at the object's leading and trailing edges. Interestingly, color breakup is also observed when the eye is stationary and an object moves by. Using a novel psychophysical procedure, we measured breakup both when viewers tracked and did not track a moving object. Breakup was somewhat more visible in the tracking than in the non-tracking condition. The video frames contained three subframes, one each for red, green, and blue. We spatially offset the green and blue stimuli in the second and third subframes, respectively, to find the values that minimized breakup. In the tracking and non-tracking conditions, spatial offsets of Δx/3 in the second subframe (where Δx is the displacement of the object in one frame) and 2Δx/3 in the third eliminated breakup. Thus, this method offers a way to minimize or even eliminate breakup whether the viewer is tracking or not. We suggest ways to implement the method with real video content. We also developed a color-breakup model based on spatiotemporal filtering in color-opponent pathways in early vision. We found close agreement between the model's predictions and the experimental results. The model can be used to predict breakup for a wide variety of conditions.