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1996 Video Quality Tutorial

Examples of Digital Video Impairments

Gradient Model of Video Quality:

The following presents an overview of the gradient model of video quality. Distortions are quantified using spatial and temporal gradients, or slopes, of the input and output video sequences. The gradient model of video quality has produced excellent correlations to subjective judgments and has a number of other significant advantages that are described in the overview. The gradient model of video quality is one model that is used in ANSI T1.801.03-1996 to derive objective video quality parameters.

• The Gradient Model of Video Quality

ANSI T1.801.03-1996 Video Quality Parameters:
The following provides a pictorial representation of several objective video quality metrics in the ANSI T1.801.03-1996 standard. These metrics are based on the Spatial Information (SI) and Temporal Information (TI) features described in section 6.1.1 of the standard. The response of selected objective video quality parameters to several common digital video impairments are illustrated.

• Reduced Reference Model for ANSI T1.801.03-1996
• Blurring Measured with the Lost Edge Energy Parameter
• Block Distortion (Tiling) Measured with the HV to non-HV Edge Energy Difference Parameter
• Temporal Edge Noise Measured with the Added Edge Energy Frequencies Parameter
• Error Blocks Measured with Added Motion Energy Parameter
• Noise Measured with Motion Energy Difference Parameter
• Jerkiness Measured with Lost Motion Energy and Percent Repeated Frames