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Data Sheet
C: Reference Picture
A: Modulation Sensitivity vs. Temporal Frequency
D: Perceptual Contrast Map
The graphs above are examples of scientific data regarding human vision
characteristics used to calibrate the human vision system model in the
PQASW. Graph (A) shows modulation sensitivity vs. temporal frequency,
and graph (B) shows modulation sensitivity vs. spatial frequency. The
use of over 1400 calibration points supports high-accuracy measurement
results.
B: Modulation Sensitivity vs. Spatial Frequency
This model has been calibrated, over the appropriate combinations of
ranges for these parameters, with reference stimulus-response data from
vision science research. As a result of this calibration, the model provides a
highly accurate prediction.
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Picture (C) is a single frame from the reference sequence of a moving
sequence, and picture (D) is the perceptual contrast map calculated by the
PQASW. The perceptual contrast map shows how the viewer perceives the
reference sequence. The blurring on the background is caused by temporal
masking due to camera panning and the black area around the jogger
shows the masking effect due to the high contrast between the background
and the jogger. The PQASW creates the perceptual map for both reference
and test sequences, then creates a perceptual difference map for use in
making perceptually based, full-reference picture quality measurements.