Abstract: A functional unit includes one or more instances of arithmetic circuitry for calculating averages. Each instance of arithmetic circuitry includes first, second and third adders, each having first and second inputs and an output that is a sum of the first and second inputs and a carry-in bit. An output of the first adder is coupled to a first input of the third adder, and an output of the second adder is coupled to a second input of the third adder. The arithmetic circuitry is able to calculate an arithmetic operation on a set of four inputs. The arithmetic operation is fully determined by control bits and may be: an average of two values (with or without rounding by 1), an average of four values (with or without rounding by 1 or 2), or a sum of four values.

Abstract: In some embodiments of the present invention, low frequency components for a current block in a current picture and a candidate block in a reference picture are obtained. For each of the low frequency components, quantized phase differences between the current block and the candidate block are calculated. Using the quantized phase differences as an index, coordinates of a global maximum of a correlation function corresponding to the quantized phase differences are retrieved from the table. The coordinates represent a motion vector. A refined candidate block is determined from a spatial search in the vicinity of a candidate block in the reference picture from which the motion vector originates when the motion vector terminates at the current block. The refined candidate block is selected as a reference block for the current block if a matching criterion between the refined candidate block and the current block satisfies a predetermined criterion.

Abstract: In some embodiments of the present invention, frequently occurring inverse linear transform results are calculated and stored in look-up-tables. In real time, incoming blocks of linear transform coefficients are divided into two or more groups. A numerical code is determined for each group and checked against a look-up-table for that group to see whether it corresponds to a pre-calculated inverse linear transform result.

Abstract: In some embodiments of the present invention, quantized frequency coefficients of a matrix of spatial data are obtained. Blocks of frequency coefficients that will be zero-valued after quantization are identified. Only frequency coefficients belonging to other blocks are calculated explicitly using the spatial-to-frequency transform.

Abstract: In some embodiments of the present invention, quantized frequency coefficients of a matrix of spatial data are obtained. Blocks of frequency coefficients that will be zero-valued after quantization are identified. Only frequency coefficients belonging to other blocks are calculated explicitly using the spatial-to-frequency transform.

Abstract: In some embodiments of the present invention, low frequency components for a current block in a current picture and a candidate block in a reference picture are obtained. For each of the low frequency components, quantized phase differences between the current block and the candidate block are calculated. Using the quantized phase differences as an index, coordinates of a global maximum of a correlation function corresponding to the quantized phase differences are retrieved from the table. The coordinates represent a motion vector. A refined candidate block is determined from a spatial search in the vicinity of a candidate block in the reference picture from which the motion vector originates when the motion vector terminates at the current block. The refined candidate block is selected as a reference block for the current block if a matching criterion between the refined candidate block and the current block satisfies a predetermined criterion.

Abstract: In some embodiments of the present invention, frequently occurring inverse linear transform results are calculated and stored in look-up-tables. In real time, incoming blocks of linear transform coefficients are divided into two or more groups. A numerical code is determined for each group and checked against a look-up-table for that group to see whether it corresponds to a pre-calculated inverse linear transform result.