VIDEO ENCODING APPARATUS AND METHOD AND VIDEO DECODING APPARATUS AND METHOD

摘要

A video encoding apparatus and method and a video decoding apparatus and method are provided to generate a scalable bit stream which consists of a base layer bit stream and an extension layer bit stream so as to have forward compatibility as supporting at least one encoding parameter of at least two depths and at least two video formats. An extension layer encoding module(230) comprises the followings. A quantization unit(231) quantizes a conversion factor provided from a DCT unit(212) into an extension quantization coefficient, and then generates an extension layer bit stream by using the quantized conversion factor, that is, the extension quantization level. A bit-depth correction unit(232) corrects the dynamic range of each quantization level so that a basis quantization level can have the same dynamic range as the extension quantization level, and then outputs the corrected quantization level.