Audio encoding system

System for the decoding of the audio signal, of the methods and techniques, with the divided frame, the frame-based system, for decoding an audio signal in a bitstream, the method and technique are provided. Each frame data in the frame and entropy that represents the audio frame - a processing information about the encoded quantization indices. Processing information includes the following: (i) the entropy codebook index, (ii) the codebook is applied to entropy-code book application information specifying ranges of the encoded quantization indices, and (iii) information window. Entropy-encoded quantization index is entropy-decoded by applying the corresponding identified range of the encoded quantization codebook index. Then inverse quantization and generates the quantization indices decoded by the sub-band samples, a set of different window functions applied in a single frame of audio data is identified and based on the window information. Time-domain audio data subband samples is reverse-conversion has been obtained by using the plural different window function indicated by the window information.