Stephen Wolf

Abstract: Digital video transmission systems consisting of a video encoder, a digital transmission method (e.g., Internet Protocol—IP), and a video decoder can produce pauses in the video presentation, after which the video may continue with or without skipping video frames. Sometimes sections of the original video stream may be missing entirely (skipping without pausing). Time varying delays of the output (or processed) video frames with respect to the input (i.e., the original or reference) video frames present significant challenges for Full Reference (FR) video quality measurement systems. Time alignment errors between the output video sequence and the input video sequence can produce measurement errors that greatly exceed the perceptual impact of these time varying video delays. This document proposes several objective video quality parameters that can be extracted from variable frame delay (VFD) information, demonstrates their correlation to subjective video quality, and shows how they can be utilized in an FR video quality measurement (VQM) system.

Keywords: measurement; video; quality; parameters; objective; subjective; correlation; calibration; dropped; frames; full reference (FR); pausing; skipping; alignment; time; variable delay

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