The natural ordering of shapes is not historically used in visualization applications. It could be helpful to show if an order exists among shapes, as this would provide an additional visual channel for presenting ordered bivariate data. Objective—we rigorously evaluate the use of visual entropy allowing us to construct an ordered scale of shape glyphs. Method—we evaluate the visual entropy glyphs in replicated trials online and at two different global locations. Results—an exact binomial analysis of a pair-wise comparison of the glyphs showed a majority of participants (n = 87) ordered the glyphs as predicted by the visual entropy score with large effect size. In a further signal detection experiment participants (n = 15) were able to find glyphs representing uncertainty with high sensitivity and low error rates. Conclusion—Visual entropy predicts shape order and provides a visual channel with the potential to support ordered bivariate data.

Contrast sensitivity functions (CSFs), which provide estimations of detection thresholds, have far-reaching applications in digital media processing, rendering, and transmission. There is a practical interest in obtaining accurate estimations of spatial and temporal resolution limits from a spatiotemporal CSF model. However, current spatiotemporal CSFs are inaccurate when predicting high-frequency limits such as critical flicker frequency (CFF). To address this problem, we modified two spatiotemporal CSFs, namely Barten’s CSF and stelaCSF, to better account for the contrast sensitivity at high temporal frequencies, both in the fovea and eccentricity. We trained these models using 15 datasets of spatial and temporal contrast sensitivity measurements from the literature. Our modifications account for two features observed in CFF measurement: the increase of CFF at medium eccentricities (of about 15 deg), and the saturation of CFF at high luminance values. As a result, the prediction errors for CFF obtained from the modified models improved remarkably.

Avoiding person-to-person collisions is critical for visual field loss patients. Any intervention claiming to improve the safety of such patients should empirically demonstrate its efficacy. To design a VR mobility testing platform presenting multiple pedestrians, a distinction between colliding and non-colliding pedestrians must be clearly defined. We measured nine normally sighted subjects’ collision envelopes (CE; an egocentric boundary distinguishing collision and non-collision) and found it changes based on the approaching pedestrian’s bearing angle and speed. For person-to-person collision events for the VR mobility testing platform, non-colliding pedestrians should not evade the CE.

Pixel designs can be made in a variety of ways to produce full color. Designs using stripe, S-stripes, pentiles, and hexagons are frequently employed. In this study, we have conducted perceptual experiments to determine the spatial frequency (CPD) threshold of each pixel design. Based on the 4 kinds of pixel design, we created various stimuli. They are stripe line-patterns that are oriented in five distinct directions (angle: 0, 90, 45, 23, and 62degrees), each with a several CPD (cycle per degrees) and contrast ratio but a similar luminance (about 70 cd/m2). As a result, the spatial frequency threshold of the hexagonal shape is lower than that of other designs in all directions. This implies that hexagonal shapes with comparatively lesser resolution may provide equivalent perceived resolution to other designs. However, there is not big difference between each design. Therefore, more research and study on different patterns or stimuli (such as text, words or images utilized in daily life) are required in the future.

Critical Flicker-Fusion Frequency (CFF) refer to the frequency at which people see a steady, single intensity of light when when given alternating bright and dark light. While most displays have been developed with a refresh rate of 60Hz, revealed as the frequency above CFF, the state-of-the-art displays with the technology called VRR(Variable Refresh Rate) are emerging, which supporting the various frequency from the lower frequency to the higher frequency than CFF. In addition, dispays have became bigger and brighter. Since it was revealed that brightness and size affect flicker perception, it is needed to inverstigate how these two factors affect flicker perception on displays with the lower refresh rate than CFF. Simulating the images with 30Hz, we observed the effect of brightness and size on display flicker perception. Additionally, we compared the result with various indices, representing the amount of flickering. As the result, participants perceived flicker stronger as luminance of stimuli increased and as the size of stimuli increased. However, none of flicker indices reflected these tendencies such as JEITA, Flicker Visibility, and Flicker Modulation Amplude. Since displayes makers generally use the flicker indices for representing the amount of flicker, there indices needs to be supplemented to include the effects of brightness and size.