Acoustic signal, encoding method and encoding device, acoustic signal, decoding method and decoding device, and recording medium image display device

摘要

A sound signal encoder for high efficiency encoding of sound signals from a plurality of channels is provided which includes a to-be-correlated object setter (52), to-be-correlated object selector (56) and a variable-length encoder (58). The to-be-correlated object setter (52) sets, on the basis of left-channel frequency information held in a left-channel frequency information holder (50) and right-channel frequency information held in a right-channel frequency information holder (51), index ÄiÜ indicating which ones of sine waves on the left channel are to be correlated with, namely, are to be subtracted from, sine waves on the right channel. The to-be-correlated object selector (56) selects a default value read from a storage unit (55) or index ÄiÜ-th amplitude information read from a left-channel amplitude information holder (53) as an object to be subtracted from the i-th amplitude information on the right channel according to the index ÄiÜ. The variable-length encoder (58) makes variable-length encoding of a difference resulted from subtraction of the left-channel amplitude information or default value as the to-be-correlated object from the amplitude information on the right channel.