JPS6356867A - High efficient coding system - Google Patents

Abstract

PURPOSE:To compress specified data quantity by applying normalizing processing sequentially to a signal block divided minutely into a block after normalizing processing is applied to the signal block being the object of coding. CONSTITUTION:Each block normallized once is divided respectively at each prescribed period while being divided further, the distribution of the signal in the amplitude direction is standardized at each new block to obtain a standardized signal subjected to application of the normalization at each new block. The processing is repeated at least once or over sequentially. The remaining parts in the signal standardizing processing by a 1st stage standardizing device 28 are move than those of a conventional system applying only one stage of signal standardizing processing by the quantity of the reduced standardized data, but the part is narrowed by the signal standardizing processing by standardizing devices 29, 30 applying the standardizing processing of the signal of a 2nd stage and the width is nearly the same as the case that the sample number N is four in the conventional system.

Description

Detailed Description of the Invention (Industrial Application Field) This technology is used in recording, transmission equipment, and other various equipment that process digital signals to efficiently encode signals with a smaller amount of information. This relates to efficiency coding methods.

(Prior art) When trying to digitize signals such as image signals and audio signals, the basic encoding method is to divide the signal level equally for each sample value and calculate the values included in each range. Linear quantization (equal quantization) is used in which quantization is replaced with one representative value.

When uniform quantization as described above is used to digitize a signal, in order to make the difference between the representative point and the original value indiscernible, it is generally necessary to use 6 bits (32nd order) for natural images. Since it is said that 8 bits (256 gradations) are required from 8 bits to 16 bits (65536 levels Ts) for audio, image signals or audio signals are digitized by uniform quantization as described above. When attempting to transmit and record digitalized signals, it is necessary to handle a large amount of information for each sample value. The problem is that it requires equipment that is larger in scale than the equipment used in other cases.

Therefore, even though the signal is encoded with a smaller amount of information, the parts where the signal changes little are sensitive to changes, and the parts where the signal changes rapidly are sensitive to changes, even if there is some error, it cannot be detected. It is well known that various high-efficiency encoding methods have been proposed in the past that take advantage of the difficult nature of human vision and hearing to reduce the amount of information for each sample.

As a specific example of the above-mentioned high-efficiency encoding method, a signal to be encoded is divided into blocks of a certain period, and the distribution of signal levels of the signals in each divided block is divided into blocks. can be transformed (normalized or normalized) so that each block has a substantially common state.

According to the conventional method, the distribution of signal levels within a block that includes a large portion of signal level changes in the signal to be encoded is widely distributed within the block; The distribution of signal levels within a block that includes a portion with little change in signal level in the signal to be encoded is biased toward some signal levels, so areas with no signal are deleted.

In the end, the signal to be encoded is in a compressed state, so the signal obtained with this conventional method is the quantization representative point when quantizing the signal to be encoded. Even if quantization is performed using fewer quantization representative points (grayscales) than the number of quantization representative points (grayscales), the error will be large for signals that are inversely transformed in the decoding system for parts with large changes, but decoding for parts with small changes Since the error in the signal that has been inversely transformed by the system is reduced, there are fewer problems in view of the aforementioned characteristics of human vision and hearing.

, when encoding is performed using the conventional method described above, information on what kind of conversion (standardization) has been performed on the signal for each block, that is, information indicating the state of standardization (standardization). However, as mentioned above, the amount of quantization information for each sample can be reduced, so it is possible to reduce the amount of information as a whole by making the block larger than a certain amount. It is.

By the way, the blocks obtained by dividing the signal to be encoded into certain intervals may be one-dimensional blocks, such as audio or image scanning lines that appear on the time axis, or images, depending on the type of signal. Two-dimensional blocks can be considered, such as when handling from both the horizontal and vertical directions, and three-dimensional blocks can also be considered, such as in the case of moving images, in which the time axis direction is also considered. Something like this is known.

"1" When the maximum and minimum values of the sample values within the block are used to standardize (normalize) the signal within the block.

Yi=k(Xi-Xw+in)/(X+sax-Xmi
n) −(1) However, l=1* 2t 3t
...NXi is the i-th input sample value (one-dimensional) Yi
is the i-th normalized sample value (one dimension) , the i-th normalized sample value Yi in the case where standardization (normalization) is performed using the maximum and minimum sample values in the block is the i-th normalized sample value Yi when the i-th input sample value Xi is the minimum sample value 1
It becomes 0 when the input sample value is set in, and becomes k when the i-th input sample value Xi is the maximum sample value Xmax in the block, so all normalized sample values for the N input sample values x1 to Xn in the block. Y1~Y
n will take a value between O and k.

"2" When the average value of the sample values within the block is used to standardize (normalize) the signal within the block.

Yi=k(Xi-Xmean)/D-(2)
However, l” 1t 2 + 3t...NXme
an=(1/N)ΣX1 ip/D indicates the degree of change, and is expressed by the following 1) to 3).

3) D=(1/N)l Xi-Xmean I
-(5) It is assumed here that the block is one-dimensional.

Next, eight consecutive samples (N = 8) corresponding to each successive fixed interval in the one-dimensional signal are considered to be samples belonging to one sequential block A and B, respectively. Taking as an example the case where
) - According to (1), as shown in "1" above, each sample in the block is calculated using the maximum value Xmax of the sample values in the block and the minimum value The case where the value Xi is normalized will be explained with reference to FIG. 3 as follows.

Figure 3(a) shows the signals (sample values) belonging to individual blocks A and B obtained by dividing the discrete signal to be encoded into fixed intervals, and the horizontal direction of the diagram shows the signals (sample values) belonging to individual blocks A and B. For example, time is taken, and on the other hand, the signal level is taken in the vertical direction, and the sequential sample values of the signal are shown by white circles, and in (a) of FIG. XinA indicates the signal level corresponding to the largest sample value among the eight samples in block A, and X inA indicates the signal level corresponding to the smallest sample value among the eight samples in block A; In (a) of the figure, XmaxB indicates the signal level corresponding to the maximum sample value among the eight samples in block B, and furthermore, Xm1n
B indicates the signal level corresponding to the minimum sample value among the eight samples in block B.

In the example shown in FIG. 3(a), the eight samples belonging to block A are present at approximately 30% of the total peak of the signal level.

The eight samples belonging to block B are shown as existing over approximately a goldmine of signal levels.

For each sample belonging to individual blocks A and H obtained by dividing the discrete signal to be encoded shown in FIG. If the distribution in the amplitude direction of the signal is normalized for each block A and B according to equation (1) above, and the standardization (normalization) process is performed for each block A and B, the result is as shown in Fig. 3. As shown in (b) of each block A.

As for the sample value for each B, the sample having the sample value corresponding to the minimum signal level in each block A, B before normalization shown in (a) of FIG. 3 is normalized to O, and Samples with sample values corresponding to the maximum signal level in each block A and B before normalization shown in (a) of Fig. 3 are normalized to k to obtain a normalized signal. It is.

Individual blocks A obtained by dividing the discrete signal to be encoded into fixed intervals as described above.

Regarding the sample value of each sample belonging to B, the distribution in the amplitude direction of the signal is normalized for each block A and B according to the equation (1) above, and the standardization is established for each block A and B. FIG. 4 shows an example of the configuration of a normalizer used to perform normalization processing.

In FIG. 4, 1 is the input terminal of the discrete signal to be encoded, and 2 to 5 are the time intervals of the aforementioned discrete signal (sampling period used to generate the discrete signal). 6 is a maximum value detection circuit, 7 is a minimum value detection circuit, 8 and 9 are quantization circuits, 10 to 15 are subtracters, 16 to 20 are dividers, 21.
22 is an output terminal for information indicating the normalization state (data indicating the normalization state), and 23 to 27 are output terminals for quantized data, which are subjected to encoding supplied to input terminal 1. The discrete signals are each supplied to a series circuit of delay circuits 2 to 5 whose time interval (sampling period used to generate discrete signal No. 3) is equal to the time interval of the discrete signal described above.

Then, at the time when the discrete signal X1 is outputted from the delay circuit 5 and given to the maximum value detection circuit 6, the minimum value detection circuit 7, and the subtracter 11, the discrete signal (A signal X2 is output and given to the maximum value detection circuit 6, minimum value detection circuit 7, and subtracter 12, and the discrete signal The discrete signal X(n-1) is supplied to the value detection circuit 6, the minimum value detection circuit 7, and the subtracter 13, and the discrete signal , the minimum value detection circuit 7, and the subtracter 14, and furthermore, the discrete signal Xn supplied to the input terminal 1 is supplied to the maximum value detection circuit 6.

The signal is applied to the minimum value detection circuit 7 and the subtracter 15.

Thereby, the maximum value detection circuit 6 detects the maximum value Xmax among the sample values x1 to Xn of the N samples in one block and provides it to the quantization circuit 8. A quantized signal obtained by quantizing Xi+ax with appropriate accuracy is supplied to the subtracter 10 as a minuend (Flt number).

In addition, the minimum value detection circuit 7 detects the minimum value X■i among the sample values X1 to Xn of N samples in one block.
n is detected and given to the quantization circuit vr9, and the quantization circuit 9 quantizes the above-mentioned minimum value It is supplied as a subtraction signal and sent to the output terminal 22.

The signal output from the subtracter 10 described above is the minimum value X min from the quantized signal for the maximum value Xmax described above.
No. 43, which is obtained by subtracting the quantized signal from Along with being sent to
It is supplied as a divisor signal to dividers 16-20.

The above-mentioned dividers 16 to 20 include the above-mentioned subtractors 11 to 20.
15 is supplied as the dividend signal, the output terminals 23 to 27 from each of the dividers 16 to 20 have Yi==k(Xi −Xm1n).
/(Xmax-Xmin)-(1)i=1.2.
...N The normalized sample values Y1 to Yn subjected to the normalized signal processing according to the above equation (1) are output.

In this way, the encoder shown in FIG. A standardized signal (normalized quantized data) obtained by normalizing the distribution in the amplitude direction of the signal according to the above-mentioned equation (1) for each of the above-mentioned individual blocks A and B is sent to the terminal 16. 20, and a signal indicating the normalization state of the signal to be set corresponding to the standardized signal (data indicating the normalization state) is output to the output terminals 21 and 22.

Note that when the signal to be encoded is multidimensional, the encoder configures the parallel distribution part of the input accordingly in order to configure a block in that dimension, and the signal in the block is , and the maximum value X
For quantization of wax and minimum value X win, it is necessary to round up the maximum value X + iax and round down the minimum value It is.

When decoding a signal encoded in this way (
It goes without saying that inverse transformation processing of equations 1) and (2) may be performed.

(Problem to be Solved by the Invention) However, in the conventional high-efficiency encoding method described above, normalization is performed only once within a block, so how to determine the number of samples N within one block? Benefits depending on how you set it up.

The disadvantages vary.

That is, in the conventional high-efficiency encoding method described above,
For example, when increasing the number of samples in one block, N,
The amount of standardized data (signal indicating the normalization state of the signal to be set corresponding to the standardized signal (data indicating the normalization state)) required for each block for decoding is: Although the amount required for each sample is small, the normalization process described above is performed uniformly within one block, so if the number of samples N in one block is large, one The state of the distribution of sample values in the amplitude direction of samples within a block tends to vary, making it difficult to perform appropriate normalization processing, so the number of quantization steps must be considerably increased when quantizing sample values. , quantization errors that are correlated with the block shape are likely to occur.

Furthermore, the quantization error that occurs in the above-mentioned state is easy to detect in view of the human visual characteristics and hearing jτ characteristics, and is therefore likely to appear as a large deterioration in image quality and sound quality. In order to prevent this from occurring, it is necessary to increase the amount of quantized data, but this naturally results in insufficient compression of the data amount.

On the other hand, if we attempt to capture the local characteristics of the signal within one block by reducing the number of samples N within one block, the amount of normalized data for each sample will increase. Samples in the block! By reducing IN1, even if the quantized data of the standardized sample values can be reduced, the overall amount of data cannot be reduced much, and Even when the number of samples N in one block may be large, such as when the signal level varies little over a wide range.

If the encoding process is performed by reducing the number of samples N in one block as described above, there is a drawback that the encoding process becomes redundant.

It is being encoded. The signal is treated as two types of discrete signal sequences with different numbers of samples in one block.

The above-mentioned problems will be explained below with reference to FIG. 5, taking as an example the case where normalization is carried out according to the above-mentioned formula (1) using the conventional method mentioned above.

Figure 5 shows the case where the number of samples N in one block is 8 ((a) and (b) in Figure 5) as an example when the size of one block is large. N is 4
The cases (Ca in FIG. 5) and (d) are taken as examples where the size of one block is small.

In addition, (a) and (e) in FIG. 5 encode the same first signal, and (a) and (e) in FIG.
In b) and (d), the same second signal is encoded.

The hatched areas in Figure 5 are areas that are excluded from quantization during the normalization process because there is no signal to be encoded, and therefore the quantization The conversion is performed on the remaining portions that are not shaded, but if the number of quantization levels (number of fk childization steps) for the standardized sample values is the same, it goes without saying that the above-mentioned The narrower the width of the remaining portion, the smaller the error caused by quantization. This is because quantization of each sample value is performed independently of normalization processing.

When signal normalization is performed by signal processing according to equation (1) above, the width of the remaining portion is determined by the maximum sample value and minimum sample value of the samples within one block. Therefore, the smaller the number of samples N in one block, the smaller the difference.

As is clear from FIGS. 5(a) and (C), the first signal becomes less than half when the number of samples N is 4 compared to the case where the number of samples N is 8, and the second signal As is clear from FIG. 5(b) and (d), the right block in FIG. 5(d) is the same as FIG. 5(b), but the signal in FIG. The block on the left in (d) is reduced to about 1/4 compared to the block shown in (b) of FIG.

From the above, when the number of quantization levels (number of quantization steps) for standardized sample values is the same, it is possible to achieve better quantization with fewer errors by reducing the number of samples in one block. Recognize.

When encoding is performed with standardization as in the example above, the standardized signal (standardized quantized data) and the standardization of the signal that should be set corresponding to the standardized signal The data transmission with the signal indicating the state (data indicating the normalization state) is shown in Table 1 below.

Table 1 However, in Table 1 above, the number of input samples is 8.
bit, quantization after normalization processing is 3 bits per value
It is assumed that the accuracy is as follows.

As can be seen from Table 1 above, the number of samples N in one block is 8, and the signal to be encoded is
For the case where is 4, the standardization of the signal is as described above (1)
When signal processing is performed according to the formula, the amount of normalized data required for normalization is 8 bits each for two types of parameters, and when the number of samples N is 8, the amount of normalized data per block is The total amount of data is 40 bits,
Also, each sample has 5 bits, which means that the original data amount was 8 bits, but the data amount has been compressed to 5/8.

Furthermore, when the number of samples N is 4, the total amount of data per block is 28 bits, and 7 bits per sample.
t, and almost no data is compressed. As described above, the conventional high-efficiency encoding method described above has a problem in that the amount of data cannot be compressed very much when encoding with relatively small quantization errors is attempted.

(Means for Solving the Problems) The present invention provides for signals belonging to individual blocks obtained by dividing a discrete signal to be encoded into fixed intervals, for each of the individual blocks.

Means for obtaining a standardized signal in a state in which the distribution in the amplitude direction of the signal is normalized for each individual block; Regarding the signals belonging to new individual blocks obtained by further dividing the individual blocks used to obtain each of the above-mentioned standardized signals into each fixed interval, the above-mentioned new For each individual block, the distribution in the amplitude direction of the signal is normalized to obtain a normalized signal in a state in which the normalization has been performed for each new individual block. In the high-efficiency encoding method characterized by repeating the process once or more, and in the muscle efficiency encoding method described above, the normalization state of the signal that should be set corresponding to the standardized signal at each stage described above. The information indicating the standardization status of the signal is the total amount of data indicating the normalization status of the signal set corresponding to one block of the standardized signal at each stage described above. The present invention attempts to solve the above-mentioned conventional problems by providing a high-efficiency encoding method that is equivalent to the amount of data indicating the normalization state of the signal that should be set when the It is something to do.

(Example) Hereinafter, specific contents of the high-efficiency encoding method of the present invention will be described in detail with reference to the accompanying drawings.

The high-efficiency encoding method of the present invention calculates the amplitude of each signal for each block, which is obtained by dividing a discrete signal to be encoded into fixed intervals. Means for normalizing the distribution in the direction to obtain a normalized signal in a state in which the normalization has been applied to each individual block; Regarding the signals belonging to new individual blocks obtained by further dividing the individual blocks used to obtain each of the standardized signals into each fixed interval.

For each new individual block, the distribution in the amplitude direction of the signal is normalized to obtain a standardized signal in a state where the normalization has been performed for each new individual block, In the high-efficiency encoding method in which the process is repeated at least once in sequence, and in the high-efficiency encoding method described above, the standardization of the signal to be set in correspondence with the standardized signal at each stage described above. The information indicating the status is the total amount of data indicating the normalization status of the signal set corresponding to one block of the standardized signal in each step, which is the total amount of data for all stages. This is a high-efficiency encoding method in which the amount of data indicating the normalization state of a signal is equal to the amount of data that should be set when standardization is performed only once, and the high-efficiency encoding method of the present invention Rather than performing standardization processing only once on the block of the signal to be encoded, as in the conventional method, the block is subjected to standardization processing and then the block is This method performs multi-stage standardization processing in which standardization processing is sequentially performed on blocks that are gradually subdivided.

In addition, if the signal standardization through multi-stage standardization processing performed in the high-efficiency encoding method of the present invention is equivalent to normalization performed only once as a result of the standardization processing through all stages, then Therefore, the amount of standardized data at each stage of the standardization process can be made smaller than the amount of standardized data when the standardization process is performed only once.

This is to ensure that equivalent quantization accuracy can be obtained even when the signal amplitude is very small and standardization accuracy is required. Although the accuracy of is reduced.

In such a case, the quantization error will eventually become large, so the decrease in the standardization accuracy described above will eventually become negligible and will not pose a major problem.

If the signal is standardized multiple times,
Since the overall state of signal change is grasped during signal standardization in the first stage, there is no problem even if the signal standardization in the subsequent stage is quite rough, so signal standardization is performed in only one stage. The amount of normalized data is
Assuming that the maximum value Xwrax and the minimum value Xm1n of sample values in one block are each 8 bits, for example, if the signal is subjected to the normalization process twice, the normalization process of the signal is In the first stage, the maximum value Xmax and minimum value Xl1in of the sample values in one block are processed by 6 bits each, and in the second stage of signal normalization processing, the sample values in one block at that time are The maximum value XmaX and the minimum value Xm1n are each about 2 bits.

In the second stage of signal standardization processing, multiple standardizers are used for signal standardization, so the overall amount of normalized data is the same as that of only one stage of signal standardization processing. Slightly more than usual.

FIG. 1 is a block diagram showing an example of the configuration of an Fi device used for multi-stage standardization of signals when implementing the high-efficiency encoding method of the present invention, and the apparatus shown in FIG. Reference numerals 28 to 30 are normalizers, and the normalizers 28 to 30 can have the same configuration as that described with reference to FIG. 4. . Further, 31 is a quantizer.

In FIG. 1, a normalizer 28 in the first stage normalizes a signal in which the number of samples N in one block is 8, and two normalizers 29 . 3
0 normalizes a signal in which the number of samples N in one block is 4, and the signal normalized by the first-stage standardizer 28 is divided into two and divided into two stages. The signal is supplied to standardizers 29 and 30, where it is further standardized, and then supplied to a quantizer 31, where it is quantized and output. Standardized data is processed by a total of three standardizers 2, the first stage standardizer 28 and the second stage two standardizers 29.30.
8 to 30, respectively, and quantized data is outputted from the quantizer 31.

Next, the state of normalized signal processing in two stages of signal normalization as described above will be explained with reference to FIG. 2, which shows the state of normalized signal processing in correspondence with FIG. 5 described above. Figure 2 shows signals (
In the figure, the horizontal direction of the diagram shows time, while the vertical direction shows signal levels, and the successive sample values of the signal are shown by white circles.

In FIG. 2, the number of samples N in one block C of the signal targeted for standardization by the first-stage standardizer 28 in FIG. 1 is 8.
, and the two standards 29. in the second stage in FIG.
30, one block El of the signal targeted for standardization,
The case where the number of samples N in E2 is 4 is shown.

In Fig. 2, X yaax C is the signal level corresponding to the maximum sample value among the 8 samples in block C, and Xm1nC is the signal level corresponding to the minimum sample value among the 8 samples in block C. and XmaxEl is the signal level corresponding to the maximum sample value among the four samples in block E1.
1nE1 indicates the signal level corresponding to the minimum sample value among the four samples in block E1, furthermore, XmaxE2 indicates the signal level corresponding to the maximum sample value among the four samples in block E2, X+m
1nE2 indicates the signal level corresponding to the minimum sample value among the four samples in block E2.

Moreover, (a) of FIG. 2 is (a) of FIG. 5 already mentioned.

It is assumed that the first signal described with reference to (c) is the signal targeted for encoding, and on the other hand, (b
) assumes that the second signal described with reference to FIGS. 5(b) and 5(d) is the signal to be encoded.

Furthermore, in the shaded areas in Figure 2, there is no signal to be encoded, so
The portions that are excluded from the quantization target during the standardization process by the first-stage standardizer 28, and the portions indicated by hatched lines in FIG. 2, are the signals targeted for encoding. Because it does not exist, the second standard is ￥1I29,
This is a portion that is excluded from the quantization target during the normalization process by No. 30.

As shown in Fig. 2, the portion remaining after the signal standardization process by the first stage standardizer 28 is normalized compared to the conventional example in which the signal standardization process is performed in only one stage. Although it is slightly larger due to the reduction in the amount of data, it has become much narrower due to the signal normalization processing by the normalizer 29 and 30 that performs the signal normalization processing in the second stage, and the sample size in the conventional example is The width is not much different from that when the number N is 4, and the quantization error of each sample value is also the same.

The standardization of the signal by the second-stage standardizer 29.30 is quite rough, with 2 bits (4 levels) each for the maximum sample value Xmax and the minimum sample value Xwin in one block. However, since the portion remaining after the signal standardization process by the first stage standardizer 28 is considerably narrow, it is sufficient to standardize the signal to the above-mentioned extent.

Correspondence between the standardized signal (standardized quantized data) and the standardized signal when the two-stage standardization process for the signal to be encoded is performed in the manner described above The following Table 2 shows the amount of data between the signal indicating the standardization state (data indicating the standardization state) of the signal to be set.

Table 2 Assuming that the amount of quantized data for each sample value is the same as in the conventional method, the difference from the conventional method is the normalized data, and in the first stage of signal normalization processing, each 6-bit In the second stage of signal normalization processing, there are two sets of 2 bits each, resulting in 20 bits for 8 samples.

From this, the amount of data per sample is 5.5 pits, which is only slightly larger than when the number of samples N is 8 in the conventional method.

As is clear from a comparison of Tables 1 and 2, the high-efficiency encoding method of the present invention has the same quantization error as the conventional high-efficiency encoding method described above when relatively small blocks are used. It has this characteristic and can significantly reduce the amount of data required.

(Effects) As is clear from the above detailed explanation, the high-efficiency encoding method of the present invention consists of individual blocks obtained by dividing the discrete signal to be encoded into fixed intervals. Means for normalizing the distribution of the signal in the amplitude direction for each of the individual blocks to obtain a normalized signal in a state in which the signal is standardized for each individual block; The standardized signals obtained in correspondence with the blocks of Regarding signals belonging to individual blocks.

For each new individual block, the distribution in the amplitude direction of the signal is normalized to obtain a standardized signal in a state where the normalization has been performed for each new individual block, A high-efficiency encoding method that is repeated at least once in sequence, and a signal standardization that should be set corresponding to the standardized signal at each stage in the above-described high-efficiency encoding method. The information indicating the status is the total amount of data indicating the standardization status of the signal set corresponding to one block of the standardized signal at each stage described above, in accordance with No. 48. This is a high-efficiency encoding method that is designed to be equivalent to the amount of data indicating the normalization state in No. 3, which should be set when standardization is performed only once. Efficiency codes and coding systems can standardize signals within a relatively small range even when the degree of change in the signal changes in a complex manner.
The processed and normalized distribution of sample values has no wasted space, so that even with relatively simple and small data volume quantization, the quantization error can be reduced; The improvement effect is remarkable in areas where the signal changes gently or in areas where small changes are adjacent to large changes, and the error in this case can be distributed rationally according to visual and auditory characteristics. Therefore, even the same amount of error can be made difficult to detect. Therefore, even if the amount of quantized data of the standardized sample value is reduced, the quality of the decoded signal can be maintained, resulting in a high data compression rate. can be realized. Furthermore, since the normalized sample values can be efficiently processed with a simple quantizer, the apparatus can be relatively simple.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an example configuration of a multi-stage signal standardization device used in the high-efficiency encoding system of the present invention; FIGS. 2, 3, and 5 are explanatory diagrams of signal processing; The figure is a block diagram showing an example configuration of a signal normalizer. 1... Input terminal of the discrete signal to be encoded, 2 to 5... Delay time equal to the time interval of the discrete signal (sampling period used to generate the M loss signal) a delay circuit that gives the signal 6...a maximum value detection circuit, 7...
Minimum value detection circuit, 8, 9... quantization circuit, 10 to 15
...Subtractor, 16-20...Divider, 21°22.
... Output terminal for information indicating the state of normalization (data indicating the state of normalization), 23-27... Output terminal for quantized data, 28-30... Standardizer, 31... Quantum Maker. Patent applicant: Victor Japan Co., Ltd. (b) Ju 3-ku (c) (d) 1. Indication of the case 1986 Patent Application No. 20216'z 2, Title of the invention High-efficiency encoding method 3, Person making the amendment Relationship to the case Patent Applicant Location 3-12 Moriyamachi, Kanayō-ku, Yokohama-shi, Kanagawa Prefecture Address name (432) Victor Company of Japan Co., Ltd. 4, agent facsimile 03 (472) 2257 No. 5, date of amendment order (self-initiated) Showa year, month, day (shipment date Showa year, month, day) 6, subject of amendment (1) details Column for detailed description of the invention in the document (2) Attached drawings (Figure 4) 7. Contents of amendment (1) Specification, page 8, lines 11 to 12 r2) D=...
・・・・(5)'' shall be corrected as follows. r2) D=(1/N)n-〒3:F...(4)1
"" 3) D=(1/N)Σ1Xi-X+++eanl
-... (s) J+1 (2) From page 27, line 11 of the specification tube to page 30, line 20, "The specifications in the first column... are sufficient." Correct it as follows. The signal standardized by the first-stage standardizer 28 is divided into two and sent to the second-stage standardizer 28.
9.30, where it is further normalized, and then supplied to a quantizer 31, where it is quantized and output. Standardized data is processed by a total of three standardizers 28 to 30, the first stage standardizer 28 and the second stage two standardizers 29°30.
The quantized data is output from the quantizer 31. Next, the state of normalized signal processing in two stages of signal normalization as described above will be explained with reference to FIG. 2, which shows the state of normalized signal processing in correspondence with FIG. 5 described above. Figure 2 shows signals (
sample value). For example, time is plotted in the horizontal direction of the diagram, while signal levels are plotted in the vertical direction, with white circles showing successive sample values of a signal. In FIG. 2, the number of samples N in one block C of the signal targeted for standardization by the first stage normalizer 28 in FIG. Two normalizers 2
9. 1 block E of the signal targeted for standardization in 30
1, the number of samples N in E2 is 4. In FIG. 2, X wax C is the signal level corresponding to the maximum sample value among the eight samples in block C, and Xm1nC is the signal level corresponding to the minimum sample value among the eight samples in block C. show,
Also, XmaxEl is the signal level corresponding to the maximum sample value among the four samples in block E1,
1nE1 indicates the signal level corresponding to the minimum sample value among the four samples in block E1, and
m1nE1 is the signal level corresponding to the maximum sample value among the four samples in block E2, and Xm1nE
2 indicates the signal level corresponding to the minimum sample value among the four samples in block E2. Moreover, (a) of FIG. 2 is (a) of FIG. 5 already mentioned. It is assumed that the first signal described with reference to (c) is the signal targeted for encoding, and on the other hand, (b
) assumes that the second signal described with reference to FIGS. 5(b) and 5(d) is the signal to be encoded. Furthermore, in the shaded areas in Figure 2, there is no signal to be encoded, so
This is the part that is excluded from the quantization target during the standardization process by the first-stage normalizer 28, and the part indicated by the hatched line in FIG. 2 is the target of encoding. Since there is no signal, the second stage normalizer 29.
This is a portion that is excluded from the quantization target during the normalization process by No. 30. As shown in FIG. 2, the portion remaining after the signal normalization process by the first stage normalizer 28 is compared to the conventional example in which the signal normalization process is performed in only one stage. Although the amount has increased slightly due to the reduction in the amount of data, 2
It has become significantly narrower due to the signal normalization processing performed by the normalizers 29 and 30, which performs the signal normalization processing on the stage signals, and the width is not much different from the case where the number of samples N is 4 in the conventional example. The quantization errors of each sample value are also the same. The normalization of the signal by the second stage normalizer 29.30 is 1
2 bits (4
Even if the standardization processing of the signal by the first-stage standardizer 28 is quite rough, as in the case of However, it is sufficient. (3) Figure 4 of the attached drawings is amended as shown in the attached sheet.

Claims (1)

[Claims] 1. Regarding signals belonging to individual blocks obtained by dividing a discrete signal to be encoded into fixed intervals, for each of the individual blocks, in the amplitude direction of the signal, Means for obtaining a normalized signal in a state in which the distribution is normalized and normalized for each individual block;
Regarding the signals belonging to new individual blocks obtained by further dividing the individual blocks used to obtain each of the above-mentioned standardized signals into each fixed interval, For each block, the distribution in the amplitude direction of the signal is normalized to obtain a normalized signal in a state in which the normalization has been performed for each new block, at least once or more. High-efficiency encoding method 2, which is characterized in that it is repeatedly performed, for signals belonging to individual blocks obtained by dividing the discrete signal to be encoded into fixed intervals, for each of the aforementioned individual blocks. , a means for obtaining a normalized signal in a state in which the distribution in the amplitude direction of the signal is normalized and normalization has been carried out for each individual block, and a means for obtaining a normalized signal in a state in which the normalization has been carried out for each individual block, and the normalization obtained corresponding to the above-mentioned individual blocks. completed signal,
Regarding the signals belonging to new individual blocks obtained by further dividing the individual blocks used to obtain each of the above-mentioned standardized signals into each fixed interval, For each block, the distribution in the amplitude direction of the signal is normalized to obtain a normalized signal in a state in which the normalization has been performed for each new block, at least once or more. In a high-efficiency encoding method that is performed repeatedly, information indicating the normalization state of the signal that should be set in correspondence with the standardized signal at each of the above steps is for one block at each of the above steps. The amount of data that is the sum of the amount of data indicating the normalization status of the signal set corresponding to the normalized signal for all stages should be set when the signal is normalized only once. High-efficiency encoding method that equalizes the amount of data that indicates the normalization state of the signal