Methods and apparatus for processing digital signals by allocation of subband signals and recording medium therefor

Claim 2

A digital signal processing method for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising the steps of: dividing the entire frequency band of the input digital signal into the plurality of sub-bands; and allocating signals of each sub-band to a plurality of sub-words divided from a word of the input digital signal; wherein, in said allocating step, information for reducing noise in at least one of the sub-bands is allocated to a sub-word different from a sub-word to which is allocated the signal of the sub-band whose noise is to be reduced.

Claim 3

The digital signal processing method as claimed in claim 1, wherein in said allocating step, the information for reducing the noise as well as the signal of the sub-band other than the sub-band whose noise is to be reduced is allocated to the sub-word to which is allocated the signal of the sub-band other than the sub-word whose noise is to be reduced.

Claim 4

The digital signal processing method as claimed in claim 2, wherein said allocating step allocates a fixed ratio of bits between the information for reducing the noise in said sub-word and the signal of the sub-band other than the sub-band whose noise is to be reduced.

Claim 5

The digital signal processing method as claimed in claim 2, wherein said allocating step allocates a fixed ratio of bits between the information for reducing the noise in said sub-signal and the signal of the sub-band other than the sub-band whose noise is to be reduced.

Claim 6

The digital signal processing method as claimed in claim 1, wherein said allocating step allocates a bit allocation which is a variable number of bits in the signals of each sub-band allocated to said plurality of sub-words.

Claim 7

The digital signal processing method as claimed in claim 5, wherein in said allocating step, the bit allocation is dynamically made in dependence upon the sub-band information and the information for reducing the noise.

Claim 8

The digital signal processing method as claimed in claim 5, wherein in said allocating step, a plurality of words of the input digital signal are grouped into a block and the bit allocation is made variable from block to block.

Claim 9

The digital signal processing method as claimed in claim 7, wherein in said allocating step, the block is variable length in dependence upon the sub-band information and the information for reducing the noise.

Claim 10

The digital signal processing method as claimed in claim 1, wherein difference information between a signal higher than a straight PCM bit rate in the signal of the sub-band whose noise is to be reduced and the signal other than the band whose noise is to be reduced is obtained and wherein, in said allocating step, the difference information is allocated to the sub-word different from the sub-word to which is allocated the signal of the band whose noise is to be reduced.

Claim 11

The digital signal processing method as claimed in claim 9, wherein the difference information is obtained from the signal of the sub-band whose noise is to be reduced and a signal of a straight PCM bit rate higher than that of the signal of the band whose noise is to be reduced.

Claim 12

The digital signal processing method as claimed in claim 10, wherein the difference information is encoded by high-efficiency encoding for reducing an information volume of the difference information.

Claim 13

The digital signal processing method as claimed in claim 11, wherein the difference information is encoded by exploiting perceptual information for reducing the information volume of the difference information.

Claim 14

The digital signal processing method as claimed in claim 11, wherein the difference information is encoded by entropy encoding for reducing the information volume of the difference information.

Claim 15

The digital signal processing method as claimed in claim 11, wherein the difference information is encoded by linear predictive coding for reducing the information volume of the difference information.

Claim 18

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising: band-splitting means for splitting the entire frequency band of the input digital signal into the plurality of sub-bands; and sub-band encoding means for allocating information for reducing the noise of at least one sub-band from the band splitting means to a sub-code different from a sub-code to which is allocated the signal of the sub-band whose noise is to be reduced.

Claim 19

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising: band-splitting means for splitting the entire frequency band of the input digital signal into the plurality of sub-bands; and sub-band encoding means for allocating information for reducing the noise of at least one sub-band from the band splitting means to a sub-code different from a sub-code to which is allocated the signal of the sub-band whose noise is to be reduced.

Claim 20

The digital signal processing apparatus as claimed in claim 16, further comprising: difference information generating means for producing difference information from a straight PCM signal of at least one of a plurality of sub-bands split by said band-splitting means and straight PCM signals of reduced word length of said sub-band for producing the information for reducing the noise.

Claim 21

The digital signal processing apparatus as claimed in claim 17, further comprising: high-efficiency encoding means for encoding the difference information for reducing an information volume of the difference information.

Claim 22

The digital signal processing apparatus as claimed in claim 17, further comprising: means for generating information indicating perceptually redundant components, and means for compressing the difference information based upon the information from said generating means for reducing an information volume of said difference information.

Claim 23

The digital signal processing apparatus as claimed in claim 17, further comprising: means for encoding the difference information by entropy encoding for reducing an information volume of the difference information.

Claim 24

The digital signal processing apparatus as claimed in claim 17, further comprising: means for encoding the difference information by linear predictive coding for reducing the information volume of the difference information.

Claim 25

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising: band-splitting means for splitting the entire frequency band of the input digital signal into the plurality of sub-bands; and sub-band encoding means for allocating signals of respective bands to a word comprising at least two sub-words, that is at least a first sub-word and a second sub-word, obtained on dividing a word of the input digital signal, wherein said sub-band encoding means allocates the signal of a sub-band whose noise is to be reduced to said first sub-word while allocating information for reducing the noise in the signal of the sub-band allocated to a pre-set subword to a sub-word different from said second sub-word.

Claim 26

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising: band-splitting means for splitting the entire frequency band of the input digital signal into the plurality of sub-bands; and sub-band encoding means for allocating signals of respective bands to a word comprising at least two sub-words, that is at least a first sub-word and a second sub-word, obtained on dividing a word of the input digital signal, wherein said sub-band encoding means allocates the signal of a sub-band whose noise is to be reduced to said first sub-word while allocating information for reducing the noise in the signal of the sub-band allocated to a pre-set subword to a sub-word different from said second sub-word.

Claim 27

The digital signal processing apparatus as claimed in claim 22, wherein said sub-band encoding means allocates the signal of the sub-band whose noise is to be reduced to said first sub-word disposed on a MSB side of the word while allocating the information for reducing the noise in the signal of the sub-band allocated to said first sub-word to a sub-code disposed on a LSB side of the word.

Claim 28

A digital signal decoding apparatus for decoding a digital signal from a signal split into a plurality of sub-bands, comprising: means for splitting from a sub-word, said sub-word being obtained from splitting a word of a digital signal, a signal of at least one sub-band whose noise is to be reduced and information for reducing the noise in said at least one sub-band, wherein the information for reducing the noise in said at least one sub-band is allocated to a sub-word different from the sub-word to which is allocated the signal of the sub-band whose noise is to be reduced; means for allocating signals of each sub-band to a plurality of sub-words; and means for synthesizing the information for reducing the noise and the signal of the sub-band whose noise is to be reduced.

Claim 29

A digital signal decoding apparatus for decoding a digital signal from a signal split into a plurality of sub-bands, comprising: means for splitting from a sub-word, said sub-word being obtained from splitting a word of a digital signal, a signal of at least one sub-band whose noise is to be reduced and information for reducing the noise in said at least one sub-band, wherein the information for reducing the noise in said at least one sub-band is allocated to a sub-word different from the sub-word to which is allocated the signal of the sub-band whose noise is to be reduced; means for allocating signals of each sub-band to a plurality of sub-words; and means for synthesizing the information for reducing the noise and the signal of the sub-band whose noise is to be reduced.

Claim 30

A recording medium having recorded therein signals produced by a digital signal processing method designed for processing an input digital signal, said recording medium being prepared by the steps of: splitting an entire frequency band of said input digital signal into a plurality of sub-bands; allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal, wherein the information for reducing the noise in at least one of said sub-bands is allocated to a sub-word different from the sub-word to which said sub-band is allocated; and recording the allocated signals on said recording medium.

Claim 31

A recording medium having recorded therein signals produced by a digital signal processing method designed for processing an input digital signal, said recording medium being prepared by the steps of: splitting an entire frequency band of said input digital signal into a plurality of sub-bands; allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal, wherein the information for reducing the noise in at least one of said sub-bands is allocated to a sub-word different from the sub-word to which said sub-band is allocated; and recording the allocated signals on said recording medium.

Claim 32

A digital signal transmitting method for transmitting a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising the steps of: splitting the entire frequency band of the input digital signal into a plurality of sub-bands; and allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal; wherein, in said allocating step, the information for reducing the noise in at least one of the sub-bands is allocated to a pre-set sub-word different from the sub-word to which has been allocated the signal of the sub-band whose noise is to be reduced; and wherein the signal of said at least one sub-band whose noise is to be reduced and the information for reducing the noise in said at least one sub-band are transmitted.

Claim 33

A digital signal transmitting method for transmitting a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, comprising the steps of: splitting the entire frequency band of the input digital signal into a plurality of sub-bands; and allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal; wherein, in said allocating step, the information for reducing the noise in at least one of the sub-bands is allocated to a pre-set sub-word different from the sub-word to which has been allocated the signal of the sub-band whose noise is to be reduced; and wherein the signal of said at least one sub-band whose noise is to be reduced and the information for reducing the noise in said at least one sub-band are transmitted.

Claim 34

A digital signal processing method for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising the steps of: forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; for at least one of said plurality of units, splitting an entire frequency band of a signal into a plurality of sub-bands; and allocating signals, where such allocation is one of allocating signals of at least one sub-band of each unit to sub-words of plural units, and allocating signals of at least one sub-band in each of said plurality of units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word.

Claim 35

A digital signal processing method for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising the steps of: forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; for at least one of said plurality of units, splitting an entire frequency band of a signal into a plurality of sub-bands; and allocating signals, where such allocation is one of allocating signals of at least one sub-band of each unit to sub-words of plural units, and allocating signals of at least one sub-band in each of said plurality of units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word.

Claim 36

The digital signal processing method as claimed in claim 27, wherein in said allocating step, sub-word length information in each sub-band is received and a sub-word length in each sub-band is fixedly allocated based upon the sub-word length information.

Claim 37

The digital signal processing method as claimed in claim 27, wherein in said allocating step, sub-word length information in each sub-band is received and a sub-word length in each sub-band is variably allocated based upon the sub-word length information.

Claim 38

The digital signal processing method as claimed in claim 27, wherein sub-word length information is received in said allocating step, and said sub-word length information is information obtained on increasing or decreasing a sub-word length allocated to a given sub-band in each block when a sum of sub-word lengths required for a given sub-band in each block is significantly smaller or larger than a sum of the sub-words allocated to said given sub-band.

Claim 39

The digital signal processing method as claimed in claim 27, wherein in said allocating step, a sub-word is allocated to a sub-band of each block based upon a sub-word length required for each sub-band previously found in all blocks.

Claim 40

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; means for splitting an entire frequency band of a signal from said means for forming into a plurality of sub-bands; and means for allocating signals, where such allocation is one of allocating signals of at least one sub-band from said means for splitting to sub-words of plural units, and allocating signals of at least one sub-band in each of said plurality of units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of ilural units, or the information in at least one sub-band in plural units is allocated to one sub-word.

Claim 41

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; means for splitting an entire frequency band of a signal from said means for forming into a plurality of sub-bands; and means for allocating signals, where such allocation is one of allocating signals of at least one sub-band from said means for splitting to sub-words of plural units, and allocating signals of at least one sub-band in each of said plurality of units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of ilural units, or the information in at least one sub-band in plural units is allocated to one sub-word.

Claim 42

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; means for splitting an entire frequency band of a signal from said means for forming into at least low-range signals and high-range signals; means for encoding said high-range signals with high-efficiency encoding for reducing the information volume of said high-range signals for reducing the noise in said low-range signals; and means for allocating, where such allocation is one of allocating the information from said encoding means for reducing the noise in said low-range signals to sub-words of said plurality of units, and allocating the information from said encoding means for reducing the noise in said low-range signals in said plurality of units to a sole sub-word.

Claim 43

A digital signal processing apparatus for processing a signal obtained on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; means for splitting an entire frequency band of a signal from said means for forming into at least low-range signals and high-range signals; means for encoding said high-range signals with high-efficiency encoding for reducing the information volume of said high-range signals for reducing the noise in said low-range signals; and means for allocating, where such allocation is one of allocating the information from said encoding means for reducing the noise in said low-range signals to sub-words of said plurality of units, and allocating the information from said encoding means for reducing the noise in said low-range signals in said plurality of units to a sole sub-word.

Claim 44

A recording medium having recorded therein signals produced by a digital signal processing method designed for processing an input digital signal, said recording medium being prepared by the steps of: splitting an entire frequency band of an input digital signal into a plurality of sub-bands for each of a plurality of units grouped from a plurality of blocks comprising a plurality of words of the input digital signal; allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal, wherein, when the signals of said sub-bands are allocated on the unit basis, such allocation is one of signals of at least one sub-band being allocated to sub-words of plural units, and signals of at least one sub-band in each of plural units being allocated to one sub-word, and wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word; and recording the allocated signals on said recording medium.

Claim 45

A recording medium having recorded therein signals produced by a digital signal processing method designed for processing an input digital signal, said recording medium being prepared by the steps of: splitting an entire frequency band of an input digital signal into a plurality of sub-bands for each of a plurality of units grouped from a plurality of blocks comprising a plurality of words of the input digital signal; allocating signals of each sub-band to a plurality of sub-words split from a word of the input digital signal, wherein, when the signals of said sub-bands are allocated on the unit basis, such allocation is one of signals of at least one sub-band being allocated to sub-words of plural units, and signals of at least one sub-band in each of plural units being allocated to one sub-word, and wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word; and recording the allocated signals on said recording medium.

Claim 46

A digital signal transmitting method for transmitting a signal obtained on processing a signal obtained in turn on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising the steps of: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; dividing an entire frequency band of a signal from said means for forming into a plurality of sub-bands from one unit to another; allocating signals, where such allocation is one of allocating signals of at least one sub-band of each unit to sub-words of plural units, and allocating signals of at least one sub-band in each of plural units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word; and transmitting the allocated signals.

Claim 47

A digital signal transmitting method for transmitting a signal obtained on processing a signal obtained in turn on splitting an entire frequency band of an input digital signal into a plurality of sub-bands, and for allocating a plurality of sub-words divided from a word of the input digital signal, comprising the steps of: means for forming a plurality of units, each unit having a plurality of blocks including a plurality of words of an input digital signal; dividing an entire frequency band of a signal from said means for forming into a plurality of sub-bands from one unit to another; allocating signals, where such allocation is one of allocating signals of at least one sub-band of each unit to sub-words of plural units, and allocating signals of at least one sub-band in each of plural units to one sub-word, wherein information for reducing noise is allocated such that the information in at least one sub-band is allocated to sub-words of plural units, or the information in at least one sub-band in plural units is allocated to one sub-word; and transmitting the allocated signals.