ENCODING METHOD OF DIGITAL DATA BY USING A BANDWIDTH EXTENDING TECHNIQUE, A DEVICE THEREOF, A DECODING METHOD AND DEVICE THEREOF, CONCERNED WITH CONTROLLING A BIT RATE ACCORDING TO NETWORK SITUATIONS

摘要

PURPOSE: An encoding method of digital data by using a bandwidth extending technique, a device thereof, a decoding method and a device thereof are provided to control a bit rate according to network situations, while guaranteeing a better quality even though a portion of a bit stream is restored in a decoding end. CONSTITUTION: An encoding device extends a bandwidth of digital data to encode the extended digital data, outputs bandwidth-limited data, and generates bandwidth extension information(1101). The encoding device encodes the bandwidth-limited data into a hierarchical structure having a base layer and at least one upper layer to control a bit rate(1102). The encoding device encodes additional information corresponding to the base layer, bit division encodes plural quantization samples corresponding to the base layer, and encodes additional information and quantization samples of a next upper layer. The encoding device multiplexes the encoded data and the bandwidth extension information, and outputs the multiplexed data and the information as a bit stream(1103).