Matsushita Electric Industrial Co., Ltd.

Takaaki Shingo

Akihiko Ohtani

Akihiko Otani

A motion vector detection device of the present invention includes: a parameter setting section having parameters relating to N (N is a natural number equal to or greater than 2) search regions obtained by dividing at least a portion of an entire search region in a search frame; a motion vector detection section for calculating an evaluation value which indicates a degree of correlation between an encoded object block in an object frame and a candidate block in one of the N search regions and for calculating a motion vector based on the evaluation value; a result storage section for storing the motion vector and the evaluation value calculated by the motion vector detection section; and a control section for controlling the motion vector detection section to calculate motion vectors and evaluation values for M (1&lE;M&lE;N) different ones of the N search regions until a predetermined condition is satisfied, for receiving the motion vectors and the evaluation values from the result storage section, and for determining the motion vector for the encoded object block.

Motion vector detection device and motion vector detection method

In order to realize a picture compression processing with a higher efficiency than ever in motion vector detection for motion picture compression coding, an improvement is provided to motion vector selection process when a plurality of candidate blocks having evaluation values of the same correlation degree have been detected from a search area. When there are a plurality of candidate blocks within the search area which have the highest correlation degree with the coding block, a difference is calculated between each of a plurality of motion vectors corresponding to the plurality of candidate blocks, respectively, and the best motion vector which is variable-coded immediately before the best motion vector which is being determined. Based on the calculated difference, the best motion vector is selected from among the plurality of motion vectors. Consequently, when the variable coding of a motion vector string is conducted by variable-coding the difference between two consecutive motion vectors, a motion vector is selected so that the code length of the motion vector string which has been variable-coded becomes short. As a result, an efficient picture compression processing can be realized.

Apparatus and method of detecting motion vectors by calculating a correlation degree between each candidate block

The present invention provides an image coding apparatus and its motion vector detection method, which can reduce a system cost also when the throughput of image data is increased. The image coding apparatus of the present invention comprises a search range frame memory for outputting a search range for motion vector detection, a coding target frame memory for outputting a coding target block, and a motion compensation unit for performing motion compensation by using the coding target block which is input from the coding target frame memory via a second data bus and the search range for the motion vector detection, which is input from the search range frame memory via a first data bus, and obtaining a candidate block having a highest correlation with the coding target block in the search range.

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Osaka, Japan

Takaaki Shingo