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across two or more pictures is known as Inter prediction. A method of further ex-
ploiting correlation between frames is to utilize motion prediction, which is re-
ferred to as Motion Compensated Prediction. Fig. 8 shows the difference of power
between several signals in a typical video coding system.
Input picture signal
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predictor
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Fig. 8
Predictive Coding Scheme
3.2.1.1 Intra Frame Prediction
Intra Frame Prediction is a prediction technique that uses the neighboring pixels
within a frame. Three prediction methods including Previous-sample Prediction,
Matrix Prediction and Plane Prediction are shown as examples of Intra Frame Pre-
diction in Fig. 9. Previous-sample Prediction uses neighboring pixels in the hori-
zontal direction as a prediction pixel, Matrix Prediction uses neighboring pixels in
both horizontal and vertical directions, and Plane Prediction uses neighboring pix-
els in horizontal direction and subtracts the pixel values at the same positions on
the former line.
3.2.1.2 Motion Compensated Prediction
Motion Compensated Prediction is a technique which creates a prediction image
that resembles the current image by linear translation of a block within a reference
picture which is already transmitted and decoded. Compression is achieved by
