Abstract: A motion estimation method capable of setting an optimum threshold value and allowing high speed processing includes the steps of: sequentially selecting one of blocks to be searched from a search range; sequentially calculating a difference between corresponding sample values of a reference block and one of blocks to be searched and accumulating an absolute value of difference; comparing an intermediate result of an accumulation value and a prescribed threshold value for a prescribed number of samples and interrupting the step of accumulating the absolute value of difference when the intermediate result exceeds the prescribed threshold value; and making one of blocks to be searched having a minimum final result of the accumulation value correspond to the reference block. The prescribed threshold value is dependent on the reference block. It is noted that the motion estimation apparatus is also disclosed.

Abstract: An adaptive difference computing element which consumes less power without any decrease in calculation accuracy includes: a first circuit receiving first and second data with the same bit lengths and each having bits at one and the other ends, determining if a prescribed relation is obtained between a bit string from each bit to the bit at one end of the first data and that of the second data for each bit of the first data and corresponding each bit of the second data, and replacing the each bit of the first data and the corresponding each bit of the second data with same predetermined bit values if the prescribed relation is obtained, and otherwise directly outputting the first and second data; and a subtracter having inputs connected to receive the first and second data from the first circuit, respectively.

Abstract: A motion estimation method capable of setting an optimum threshold value and allowing high speed processing includes the steps of: sequentially selecting one of blocks to be searched from a search range; sequentially calculating a difference between corresponding sample values of a reference block and one of blocks to be searched and accumulating an absolute value of difference; comparing an intermediate result of an accumulation value and a prescribed threshold value for a prescribed number of samples and interrupting the step of accumulating the absolute value of difference when the intermediate result exceeds the prescribed threshold value; and making one of blocks to be searched having a minimum final result of the accumulation value correspond to the reference block. The prescribed threshold value is dependent on the reference block. It is noted that the motion estimation apparatus is also disclosed.