METHOD AND APPARATUS FOR SCALING BIT STREAM OF COMPRESSED VIDEO

摘要

PROBLEM TO BE SOLVED: To obtain a scaling method and device for the bit stream of a compressed video signal in which high fidelity information of an original signal can be used as much as possible, and a picture quality close to a signal prepared by encoding an original source with a low rate can be obtained. SOLUTION: This device includes partial decoding hardware 38 and 41 for removing a high frequency AC discrete cosine conversion coefficients or re- quantizing data quantized with a coarser quantization coefficient. Scaling is operated based on a block (macro-block) for linearly operating the scaling of the amounts of compressed data for each block. An analyzer 40 prepares the profile of a cumulatively and partially decompressed data in a video frame, and a scaling 42 of a bit stream ensures that the profile of the scaling-processed signal is substantially suited to the profile of an original data.