Method for coding motion in video sequence

Abstract

A method of motion-compensated video encoding that enables a video sequence with a global motion component to be encoded in an efficient manner. A video encoder (600) is arranged to assign macroblocks to be coded to specific coding modes including a skip mode, which is used to indicate one of two possible types of macroblock motion: (a) zero motion, or (b) global or regional motion. As each macroblock is encoded, a previously encoded region surrounding the macroblock is examined and the characteristics of motion in that region determined. With the skip mode, the macroblock to be coded and a motion vector describing the global motion or regional motion is associated with the macroblock if the motion in the region is characteristic of global motion or regional motion. If the region exhibits an insignificant level of motion, a zero valued motion vector is associated with the macroblock.

Description

technical field [0001] The present invention relates generally to communication systems, and more particularly to motion compensation in video coding. Background technique [0002] Like ordinary moving images recorded on film, a digital video sequence consists of a series of still images. By displaying successive images of the sequence one after the other at a relatively fast rate, usually 15-30 frames per second, it is possible to Creates the illusion of movement. Due to the relatively fast frame display rate, the images in consecutive frames are likely to be very similar and thus contain considerable redundant information. For example, a common scene may consist of some stationary units, such as background objects, while some moving regions, which may vary in shape, such as a newscaster's face, may be in rapid motion. Alternatively or additionally, so-called "global motions" may occur in the video sequence, eg due to panning, panning or zooming of the camera recording th...

AI Technical Summary

Problems solved by technology

However, this warping handles motion complex and additional information must be conveyed in the encoded video bitstream to ensure correct decoding of the video sequence

Although the related techniques of global motion vector coding require fewer calculations than global motion compensation, it does increase the complexity of the encoder, and additional information must be transmitted in the video bitstream to ensure the correct decoding of video data.

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