Boundary matching motion estimation apparatus

Claim 1

An apparatus for determining a motion vector representing a displacement between a current frame and a previous frame of video signals, wherein the current frame is divided into a plurality of search blocks of an equal size and the previous frame has a plurality of search regions of a size larger than said equal size of a search block, each search region including a multiplicity of candidate blocks of said equal size, which comprises: means for detecting displacement vectors and error functions between a search block in the current frame and said multiplicity of candidate blocks included in a search region corresponding to the search block; means for comparing the error functions to each other and selecting M number of error functions in the order of their magnitude beginning from the smallest error function, M being an integer larger than 1; means for selecting M number of respective displacement vectors from said detected displacement vectors, said M number of displacement vectors corresponding to said M number of error functions; means for selecting M number of respective candidate blocks from said multiplicity of candidate blocks, said M number of candidate blocks being derived from said selected M number of displacement vectors; means for generating M sets of boundary differences, wherein each of said M sets of boundary differences represents the differences between the boundary pixels, in each of the M candidate blocks, and pixels neighboring said boundary pixels, said neighboring pixels being included in the current frame; means having M number of comparison and counting sections, wherein each of the comparison and counting sections compares each boundary difference in one of said M sets of boundary differences with a predetermined value, to count the number of the boundary differences having a value larger than the predetermined value; and means for selecting a counted number having a minimum value to thereby determine one of said M number of displacement vectors which corresponds to the selected counted number, as the motion vector for said search block.

Claim 2

An apparatus for determining a motion vector representing a displacement between a current frame and a previous frame of video signals, wherein the current frame is divided into a plurality of search blocks of an equal size and the previous frame has a plurality of search regions of a size larger than said equal size of a search block, each search region including a multiplicity of candidate blocks of said equal size, which comprises: means for detecting displacement vectors and error functions between a search block in the current frame and said multiplicity of candidate blocks included in a search region corresponding to the search block; means for comparing the error functions to each other and selecting M number of error functions in the order of their magnitude beginning from the smallest error function, M being an integer larger than 1; means for selecting M number of respective displacement vectors from said detected displacement vectors, said M number of displacement vectors corresponding to said M number of error functions; means for selecting M number of respective candidate blocks from said multiplicity of candidate blocks, said M number of candidate blocks being derived from said selected M number of displacement vectors; means for generating M sets of boundary differences, wherein each of said M sets of boundary differences represents the differences between the boundary pixels, in each of the M candidate blocks, and pixels neighboring said boundary pixels, said neighboring pixels being included in the current frame; means having M number of comparison and counting sections, wherein each of the comparison and counting sections compares each boundary difference in one of said M sets of boundary differences with a predetermined value, to count the number of the boundary differences having a value larger than the predetermined value; and means for selecting a counted number having a minimum value to thereby determine one of said M number of displacement vectors which corresponds to the selected counted number, as the motion vector for said search block.