High efficiency audio coding device and method therefore

A high efficiency encoding device for audio signals comprising:

• spectral data transforming means for transforming audio signals into spectral data from one predetermined time frame to another;
• quantization means for dividing said spectral data into plural blocks and quantizing said spectral data by adaptive bit allocation for each of said blocks, thereby generating quantized signals;
• encoding means for encoding said quantized signals;
• allowable noise energy calculating means for calculating a first order and a second order allowable noise energy for each of said blocks, said block for which the first and second order allowable noise energies is being calculated being designated a current block, wherein the allowable noise energy calculating means further comprises:
• signal energy calculating means for calculating signal energies for each of said blocks;
• means for calculating the first-order allowable noise energy for the current block from the signal energies by utilizing characteristics of human auditory sense;
• and
• means for calculating the second-order allowable noise energy for the current block by summing a weighted first-order allowable noise energy for the current block and a weighted second-order allowable noise energy for a previous block;
• and
• bit allocation means for finding the allocation bit number based on the allowable noise energies as found by said allowable noise energy calculating means, wherein said spectral data is quantized by said quantization means based on said bit allocation number.