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Institute for Telecommunication Sciences / Resources / Video Quality Research / Guides and Tutorials / ANSI Video Quality Tutorial / Temporal Edge Noise Measured with the Added Edge Energy Frequencies Parameter

Temporal Edge Noise Measured with the Added Edge Energy Frequencies Parameter

Temporal edge noise is defined in ANSI T1.801.02-1996 as "A form of edge busyness characterized by time-varying sharpness (shimmering) to edges of objects."

The series of video frames below, together with the accompanying graphs, illustrate the use of the added edge energy frequencies parameter for quantifying temporal edge noise. Three consecutive frames of the input video are shown for the cirkit test scene (see ANSI T1.801.01-1995). The cirkit test scene is a circuit diagram that contains lines and letters. The corresponding spatial information (SI) images are shown to the right of each frame. The input video has an approximately constant amount of edge energy (shown as white). The corresponding sequence of output video frames that contain temporal edge noise are shown along with their SI images. Output frames 3 and 1 contain less SI than output frame 2. The successive blurring and sharpening of the edges, perceived as a shimmering of the edges, creates large swings in the measured SI values for the sequence of output video frames.

The accompanying graph of the SI time histories, where the input is plotted with a green line and the output is plotted with a red line, demonstrates the swings in the SI values for the output. The added oscillations of the SI values for the output video sequence create extra high frequencies. This is demonstrated by the accompanying graph of SI frequencies, where the output (red line) has more energy over all frequencies.

tempsitime.jpg tempsifreq.jpg

 

Input SI of Input   Output SI of Output
tempin.jpg tempinsi.jpg Frame
3
tempout1.jpg tempout1si.jpg
tempin.jpg tempinsi.jpg Frame
2
tempout2.jpg tempout2si.jpg
tempin.jpg tempinsi.jpg Frame
1
tempout1.jpg tempout1si.jpg
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