METHOD FOR INVERSE QUANTIZATION OF COMPRESSED AND ENCODED VIDEO DATA STREAM AND APPARATUS THEREOF

摘要

A method for inverse quantization of a compressed/encoded video data stream and an apparatus thereof are provided to remove four addition processes from the whole process of the inverse quantization, thereby increasing the whole process speed and reducing the embodiment area of hardware. A method for inverse quantization of a compressed/encoded video data stream comprises the following steps of: shifting a frequency-converted or quantized coefficient value left or inverting the coefficient value to multiplex the coefficient value(610); adding a carry-in value to the multiplexed coefficient value and setting the lowest bit value(620); multiplying the set coefficient value by a quantization scale value(630); multiplying a multiplication result value by a quantization weight(640); and truncating the decimal place of a value that the quantization weight is multiplied and adding an added value determined according to whether the number without truncated decimal place is a positive number or a negative number or whether the number without truncated decimal place is a positive even number or a negative odd number to the remaining integral place of the truncated value(650).