Patent ID: 7817719

Claim:
A video conferencing motion estimation system, the system comprising: a microprocessor, the microprocessor being configured to operate as a compression and decompression (CODEC) device, the CODEC device including; a first operand register, the first operand register configured to store a first set of binary data as 2's complement; a second operand register, the second operand register configured to store a second set of binary data as 2's complement; an arithmetic logic unit, the arithmetic logic unit having a first input and a second input, the first input coupled to receive the first set of binary data and the second input coupled to receive the second set of binary data, the arithmetic logic unit further having an add/subtract enable input, the add/subtract enable input coupled to receive a most significant bit of the second set of binary data, the most significant bit representing a sign of the second set of binary data, the arithmetic logic unit being configured to add data input from the first and second operand registers if the most significant bit is of a first value and subtract the second set of binary data from the first set of binary data if the most significant bit is of a second value; a destination register, the destination register coupled to an output of the arithmetic logic unit to receive a result; and a multiplexer, the multiplexer having a first input and a second input, an output, and a select terminal, the output being coupled to the add/subtract enable input of the arithmetic logic unit, the first input being coupled to receive the most significant bit of the second set of binary data, and the second input being coupled to an add/subtract control line.