Patent ID: 8130839

Claim:
An information processing apparatus comprising: a processing load detecting unit configured to detect a processing load; an input unit configured to input moving picture signal; a motion estimation unit configured to detect the inter-frame motion of blocks obtained by dividing an input picture constituting the input moving picture signal in a square region which is set according to the processing load detected at the processing load detecting unit and whose diagonal line is parallel to one side of the blocks; a motion compensation prediction unit configured to generate a prediction signal based on the result of the detection at the motion estimation unit; a conversion unit configured to convert a prediction residual error signal obtained from a residual error in the prediction signal and the input picture signal; and an output unit configured to encode a conversion coefficient converted at the conversion unit, and to output an encoded stream, wherein the motion estimation unit detects motion by searching in a rectangular region, sets a search range composed of an overlapping part of a rectangular region whose one side is parallel to one side of the blocks and the square region, and changes the search range for motion detection by changing the square region according to the processing load detected at the processing load detecting unit, and wherein, if sum of absolute differences between an original picture and a reference picture is SAD, a Lagrange multiplier is λ M , sum of the coding amount of a difference vector and the coding amount of a reference index is R, expected value of SAD decreased in searching is ΔE SAD , and the SAD and R0 of a motion vector optimum at the time are SAD0 and R, the SAD in a search center position is SAD1, and the R of a motion vector to be detected is R2, the motion estimation unit sets all motion vectors m satisfying R 2( m )< R 0−( SAD 1−α×Δ E SAD −SAD 0)/λ M (1) as the square region, and sets a motion estimation region by setting constant α in expression (1) to any value in the range of 0 or more and 1 or less according to the processing load detected at the processing load detecting unit.