JPH07283756A - Method and device for signal processing and signal recording medium - Google Patents

Abstract

PURPOSE:To effectively switch the reproduction levels in the reduced frequency even for reproduction of plural signals by recording or transmiting the maximum level of each partial signal together with an actual signal. CONSTITUTION:An absolute value calculation circuit 201 calculates the absolute value of the time series sample data, i.e., the actual signal supplied from a terminal 200 and sends this absolute value to a maximum value deciding circuit 208 of a maximum value setting part 207 together with the supplied sample data. A maximum value coding circuit 204 detects the maximum value to an index out of the sample data supplied from the terminal 200 and codes this maximum value to send it to a maximum value output circuit 205. In a reproduction state, the maximum value of the circuit 205 is compared with the maximum value of the partial signal to be reproduced. If the former maximum value is larger than the latter value, the level of the relevant part is automatically set at the level of the partial signal of the maximum value for reproduction of the signal. Thus the reproduction levels can be effectively switched.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal processing method and apparatus for recording and transmitting or reproducing digital signals such as music and voice, and a signal processed by this signal processing method. The present invention relates to a signal recording medium.

[0002]

2. Description of the Related Art Conventionally, when recording (recording) signals such as music and voice on a recording medium such as a so-called compact disc (CD), the recording level is usually different from each other. . That is, in a plurality of compact discs, the level of the recorded signal is different for each disc.

Therefore, for example, a plurality of music songs reproduced from a plurality of compact discs (CDs),
For example, when recording is performed on a single recordable / reproducible disc or the like, since the levels of the signals reproduced from the respective compact discs are different as described above, the single disc on which the plurality of songs are recorded is reproduced. In this case, the user needs to switch or control the reproduction level for each song.

[0004]

That is, in general terms, music or voice recorded in one recording medium or music or voice transmitted from one transmission medium is divided into several parts. When divided (for example, when divided for each song), if the recorded or transmitted level differs for each part, it is necessary to switch the reproduction level for each part when reproducing.

Therefore, the user must frequently perform the level switching operation at the time of reproduction, the operation becomes very complicated, and the burden on the user increases.

Therefore, the present invention has been made in view of such a situation, and even when reproducing a signal recorded or transmitted by being divided into a plurality of parts, the user frequently changes the reproduction level. It is an object of the present invention to provide a signal processing method and apparatus and a signal recording medium that enable effective switching of the reproduction level without needing to perform the operation.

[0007]

The present invention has been proposed in order to achieve the above object, and the signal processing method of the present invention is a signal processing method of an actual signal composed of a plurality of partial signals. The maximum value of the signal level of each partial signal is detected, and the maximum value is recorded or transmitted together with the actual signal. Here, the actual signal to be recorded or transmitted and the maximum value can be encoded, and the logical sum of the absolute values of the partial signals can be used as an approximate value of the maximum value.

Next, the signal recording medium of the present invention records the signal processed by the signal processing method of the present invention.

Further, in the signal processing method for reproducing the signal recorded or transmitted by using the signal processing method of the present invention, recording or transmission is performed according to the signal processing method at the time of recording or transmission. Prior to the reproduction of the actual signal,
The maximum value among the maximum values recorded or transmitted for the signal level of each partial signal is detected, and the value obtained by dividing the detected maximum value by the maximum value of each partial signal is Multiply by each partial signal. Further, when the recorded or transmitted maximum value is encoded, the encoded maximum value is decoded prior to reproduction of the actual signal, and the maximum value among the decoded maximum values is obtained. Is detected and the maximum value thereof is divided by the maximum value of each partial signal, and the value is multiplied for each partial signal at the time of reproducing the actual signal. Further, prior to the reproduction of the encoded actual signal, the maximum value among the recorded maximum values of the signal level of each partial signal is detected, and the detected maximum value is the maximum value of each partial signal. The value divided by the value is multiplied for each partial signal decoded at the time of reproducing the actual signal. Furthermore, when both the actual signal and the local maximum value are encoded, the encoded local maximum value in which the signal level of the partial signal is recorded or transmitted is decoded before the reproduction of the encoded actual signal. The maximum value in each of the decoded local maximum values, and the value obtained by dividing the detected maximum value by the local maximum value of each partial signal is decoded for each partial signal when reproducing the actual signal. To ride.

Further, in the signal processing method of the present invention, a value of a power of 2 may be used as an approximate value of a multiplier by which each of the above partial signals is multiplied, and a bit shift may be used as the multiplication.

Next, the signal processing apparatus of the present invention is a signal processing apparatus for an actual signal composed of a plurality of partial signals, and has detection means for detecting the maximum value of the signal level for each partial signal of the actual signal. The maximum value is recorded or transmitted together with the actual signal. Also in the signal processing device of the present invention, the actual signal to be recorded or transmitted and the maximum value can be encoded. Further, a logical sum of absolute values of the partial signals can be used as an approximate value of the maximum value.

Further, the signal processing apparatus for reproducing the recorded or transmitted signal processed by using the signal processing method of the present invention includes a signal for each partial signal prior to reproduction of the recorded or transmitted actual signal. Detection means for detecting the maximum value among the maximum values recorded or transmitted, and a value obtained by dividing the detected maximum value by the maximum value of each partial signal for each partial signal when reproducing the actual signal. And multiplication means for multiplying by. Here, when the recorded or transmitted maximum value is encoded, the detecting means decodes the encoded maximum value of the signal level of each partial signal, and then detects the maximum value of each maximum value. Detect the value. Further, the multiplication means when the recorded or transmitted actual signal is encoded is such that the maximum value detected by the detection means is divided by the local maximum value of each partial signal, and the value is decoded at the time of reproducing the actual signal. Multiply by each partial signal. Furthermore, when both the actual signal and the maximum value are encoded, the encoded maximum value recorded or transmitted by the detecting means is decoded, and the maximum value among the decoded maximum values is obtained. And a value obtained by dividing the detected maximum value by the maximum value of each partial signal in the multiplication means is multiplied for each partial signal decoded at the time of reproducing the actual signal.

Also in the signal processing device of the present invention, a value of a power of 2 can be used as an approximate value of a multiplier by which each of the partial signals is multiplied, and bit shift can be used as the multiplication.

Further, the signal processing apparatus of the present invention for reproducing the signal recorded or transmitted by the signal processing method of the present invention can control the reproduction level in an analog manner. Prior to the reproduction of the transmitted actual signal, it has a control means for recording or transmitting the signal level of each partial signal or supplying the maximum value, and the control means is the maximum of the maximum values. The value is detected, and the reproduction level is controlled in an analog manner for each partial signal at the time of reproducing the actual signal according to the maximum value and the maximum value of each partial signal. Further, the signal processing device for controlling the reproduction level in an analog manner is provided with a detecting means for detecting the maximum value at which the signal level of each partial signal is recorded or transmitted and the maximum value among the respective maximum values. The provision and control means can control the reproduction level in an analog manner for each partial signal when reproducing the actual signal in accordance with the maximum value and the maximum value of each partial signal detected by the detecting means.

Further, in the signal processing apparatus of the present invention for controlling the reproduction level in an analog manner, when the maximum value to be recorded or transmitted is encoded, the encoded maximum value is supplied to the control means. , The control means decodes the maximum value, detects the maximum value among the decoded maximum values, and reproduces each part when reproducing the actual signal according to the maximum value and the maximum value of each partial signal. It is also possible to control the reproduction level in an analog manner for each signal. Furthermore, the coded local maximum value can be decoded by the decoding means before being sent to the control means, and the detection means outputs the maximum value among the respective local maximum values from the output of the decoding means. By detecting the maximum value of, the control means controls the reproduction level in an analog manner for each partial signal at the time of reproducing the actual signal according to the detected maximum value and maximum value.

[0016]

According to the signal processing method and apparatus of the present invention, when recording or transmitting an actual signal composed of a plurality of partial partial signals, the maximum value of the signal level of each partial signal is detected and the maximum value is detected. Is recorded or transmitted together with the actual signal, and at the time of reproduction, the maximum value of the maximum value is compared with the maximum value of the partial signal to be reproduced, and if the maximum value of the partial signal to be reproduced is smaller, The level of that portion is automatically reproduced in accordance with the level of the maximum partial signal.

Further, according to the signal recording medium of the present invention, since the maximum value of the signal level for each partial signal is recorded together with the actual signal, the maximum value can be used for the level control during reproduction. become.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a flow chart showing an operation explanation when recording or transmitting a signal in a signal processing apparatus to which the signal processing method of the present invention is applied. Steps S2 to S9 in FIG. 1 represent the processing steps of the operation of the main part.

In the first step S1 in FIG. 1, time-series sample data of voice or music is input as an actual signal. The signal input here may be, for example, a read from a recording medium or a terminal input from another device, and the input method is not particularly limited, and various methods can be applied.

In the next step S2, it is determined whether or not the index indicating which part of the whole the input time-series sample data is included in has changed from that of the previous sample. To do. It should be noted that this index can be considered to be the same as the index of the Q data format of the compact disc, and therefore, the above-mentioned portion can be exemplified by a digital signal such as a music piece. Also, the index is the same as in the case of the above time-series sample data,
There is no particular limitation on how the input is made. If it is determined in step S2 that the index has changed (YES), the process proceeds to the next step S3, and if it is determined that the index has not changed (NO), the process proceeds to step S6.

In step S3, it is determined whether or not the current index is "1". If it is determined to be "1" (Yes), the process proceeds to step S6, and if it is determined not to be "1" (NO). ), The process proceeds to step S4.

In step S4, the maximum value of each sample data, that is, the partial signal corresponding to the current preceding index is output, and the process proceeds to the next step S5. In step S5, the previously stored maximum value is cleared to zero, and the process proceeds to step S6.

In the next step S6, the stored maximum value is compared with the absolute value of the input sample data, and if the maximum value is greater than or equal to (YES), the process proceeds to step S8 and conversely the maximum value. If the value is smaller (no), the process proceeds to step S7.

In step S7, the absolute value of the input sample data is substituted for the maximum value, and the process proceeds to step S8. Here, instead of substituting the absolute value of the input sample data for the maximum value, it is possible to substitute an approximate value that is a value close to the absolute value of the input sample data.

In the next step S8, the input sample data is copied to the input sample buffer and the next step S8 is executed.
Proceed to 9.

In step S9, it is determined whether or not the number of samples stored in the input sample buffer is equal to the number of samples n preset for encoding, and when it is determined that they are equal (Yes). To step S10, and if it is determined that they are not equal (NO), the procedure returns to step S1.

In step S10, coding is performed using each sample data of the sample number n stored in the input sample buffer, and the process proceeds to the next step S11.
Here, the above n varies depending on the encoding method, and n = 1 may be used to encode one sample at a time.
May be set to a plurality to encode a block composed of the plurality of samples, and, for example, compression encoding as described later may be used. Also, step S1
It is also possible to directly record or transmit the input sample data without performing the encoding of 0. In this case, if the above steps S8 and S9 are omitted or if not omitted, it is considered that n = 1. Good. In addition, although the present embodiment describes the example of performing the encoding, it may be possible not to perform the encoding as described above. Here, regarding the encoding method and whether or not to perform the encoding. No particular limitation is imposed. When the encoding is not performed, the input signal, that is, the actual signal is directly output when the signal is output in step S12 described later.

Step S11 following step S10
Then, all the data in the used input sample buffer are replaced with 0 and the process proceeds to the next step S12. In step S12, the encoded signal is output, and then the process ends. In addition, this step S12,
If steps S8 and S9 are omitted, they are naturally omitted.

Next, FIG. 2 shows a configuration of a main part when recording or transmitting in the signal processing apparatus of the embodiment of the present invention to which the signal processing method of the present invention is applied.

In FIG. 2, the absolute value calculation circuit 201
Performs a process of calculating the absolute value of the time-series sample data, which is the actual signal supplied from the terminal 200, and sending the absolute value to the maximum value determination circuit 208 of the maximum value setting unit 207 together with the input sample data. .

Further, the index judgment circuit 203 has
Data of an index indicating which part of the whole the input sample data is included in the signal is supplied via a terminal 202, and the index determination circuit 2
In 03, if the index is different from the previous index, the process of sending the index to the maximum value encoding circuit 204 is performed.

The maximum value encoding circuit 204 detects the maximum value for the index from the input sample data from the terminal 200, encodes the supplied maximum value and outputs it, and this is the maximum value output circuit. Sent to 205. As the encoding method in the maximum value encoding circuit 204, for example, a method using the number of bits of the maximum value as a code or various methods such as a normalization coefficient used when encoding the input sample data is used. Though conceivable, no particular limitation is made here. Further, since the encoding of the local maximum value is not an essential condition in the present invention,
It may not be performed. The flowchart of FIG. 1 described above shows an example in which the encoding is not performed.

In the next maximum value output circuit 205, the maximum value obtained by processing each sample data corresponding to the immediately preceding index, that is, the partial signal, is output via the terminal 217 and the maximum value is output. Is sent to the maximum value zero clear circuit 206.

In the local maximum value zero clear circuit 206, the memory used for storing the local maximum value is cleared to zero in accordance with the identification signal, and the local maximum value setting unit 20 is also provided.
An identification signal indicating that the zero has been cleared is sent to the maximum value determination circuit 208 of No. 7.

The maximum value judgment circuit 208 compares the maximum value obtained by the processing up to each sample data corresponding to the immediately preceding index with the absolute value output from the absolute value calculation circuit 201, and When the maximum value is larger, the time series sample data itself sent from the absolute value calculation circuit 201 is sent to the input sample buffer 211 of the signal encoding unit 210. On the contrary, when the absolute value of the sample data this time is larger, not only the time-series sample data is sent to the input sample buffer 211, but also the absolute value is sent to the maximum value substitution circuit 209.

In the maximum value substitution circuit 209, the inputted absolute value is substituted into the memory assigned to the maximum value.

The maximum value determining circuit 207 and the maximum value substituting circuit 209 constitute a maximum value setting section 207 for setting a maximum value. Instead of these processes, the absolute value output logic of the absolute value calculating circuit 201 is used. You may decide to take the sum and output as an approximate value of the maximum of this partial signal.

In the next signal coding section 210, the data of the number of samples stored in the input sample buffer 211 is sent to the sample number judging circuit 212, and the sample number judging circuit 212 presets for coding. Number n
It is determined whether or not only sample data is stored. When the sample number determination circuit 212 determines that the number of samples stored in the input sample buffer 211 is less than the required sample number n, an identification signal indicating that is sent to the absolute value calculation circuit 201. Thus, the above-described processing for the new input sample is performed. When the sample number determination circuit 212 determines that the required number of samples has been stored in the input sample buffer 211, the sample number determination circuit 212 sends an identification signal to that effect to the signal encoding circuit 213. To be

When the identification signal is supplied, the signal encoding circuit 213 encodes the sample data of the sample number n supplied from the input sample buffer 211, and outputs the encoded sample data as a signal. When the processing is finished, the sample buffer zero clear circuit 2 sends an identification signal indicating the fact to the circuit 215.
Send to 14.

The sample buffer zero clear circuit 21
In 4, when the identification signal indicating the end of the processing is supplied from the signal encoding circuit 213, the input sample buffer 211 is cleared to zero.

The signal coding unit 210 is composed of the input sample buffer 211, the number-of-samples judging circuit 212, the signal coding circuit 213, and the sample buffer zero clear circuit 214 described above, but when the coding of the sample data is not performed. Does not require these components, and the output of the maximum value determination circuit 208 is directly sent to the signal output circuit 215.

In the signal output circuit 215, the supplied encoded sample data (when the encoding is not performed, the unencoded sample data itself) is output to the external terminal 216 or the like, and the processing ends. To do.

Next, FIG. 3 is a flow chart showing the operation of reproducing a signal in the signal processing apparatus of the present invention. Steps S21 to S39 in FIG. 3 show processing steps of the reproducing operation.

In FIG. 3, in step S21,
As initialization, the maximum value of the maximum value and the index are set to 0, and the process proceeds to the next step S22.

In step S22, the encoded maximum value corresponding to each sample data of the current index, that is, the partial signal reproduced or transmitted from the recording medium is input, and the process proceeds to the next step S23. In this step S23, the encoded maximum value is decoded, and the process proceeds to the next step S24. Note that the encoding and decoding methods here are not particularly limited as in the recording or transmission operation described above.
If the input maximum value is uncoded data, step S23 is omitted.

In step S24, the decoded maximum value (or the non-encoded maximum value itself when not encoded) is compared with the maximum value among the maximum values up to that point, If the decoded maximum value is larger than the maximum value (Yes), then the next step S2
If the maximum value is larger (NO), the process proceeds to step S26.

In step S25, the maximum value is
Substituting the decrypted local maximum value, the next step S2
Go to 6. In step S26, it is determined whether or not the above-described processing has been completed for all indexes. If not completed (No), the process moves to the next index in step S27, and then the process returns to step S22. On the contrary, if it is determined in step S26 that the above process has been completed for all indexes (Yes),
Then, the process proceeds to next step S28.

In the signal processing apparatus of this embodiment, the maximum values of the maximum values of all partial signals of the reproduced signal (actual signal) to be reproduced are obtained in the above steps S21 to S28.

Next, in step S28, the index for reproduction is set to 0 again and the next step S28.
Proceed to 29. In step S29, the coded local maximum value of the partial signal corresponding to the current index is input, and then the process proceeds to step S30. This step S30
Then, the encoded maximum value is decoded. If the maximum value is not encoded and recorded or transmitted as described above, step S30 is omitted.

In the next step S31, the step S
At the time when the processing is completed in 26, a value p obtained by dividing the already obtained maximum value by the maximum value obtained in step S29 is obtained, and then the process proceeds to step S32.

In step S32, the encoded and recorded or transmitted sample data is input, and the process proceeds to step S33. In this step S33, it is determined whether or not the input has been performed for n samples necessary for decoding, and when it is determined that the input for n samples has not been completed (No), the process returns to step S32. If it is determined that the process has been completed (Yes), the next step S34
Proceed to.

In this step S34, the above n pieces of sample data are decoded, and the process proceeds to the next step S35.
Since steps S32 to S34 are steps necessary when the signal is encoded and recorded or transmitted, the signal is not encoded and is recorded or transmitted as it is. Omitted if done.

In the next step S35, step S34
After multiplying each sampled data decoded in
It proceeds to step S36. In this step S36, n pieces of sample data multiplied by p in the above step S35 are output, and the process proceeds to step S37.

In this step S37, it is determined whether or not the index value corresponding to the next sample has changed. If it is determined that the index value has not changed (NO), the process returns to step S32, and the signal If it is determined that the decoding is continued and changed (Yes), the process proceeds to step S38.

In step S38, it is determined whether or not the above-described processing has been completed for the partial signals corresponding to all the indexes. If it is determined that the processing has not been completed (NO), the process proceeds to the next step S39. , The step S3
After incrementing the index value by 1 in step 9, step S2
Return to 9. On the other hand, if it is determined in step S38 that the processing has ended (Yes), the signal reproduction processing ends.

Next, FIG. 4 shows a configuration for performing the above reproduction of a signal processing apparatus using the signal processing method of the present invention.

In FIG. 4, in the maximum value decoding circuit 242 of the maximum value setting section 241, the maximum value detected by the signal processing apparatus of the embodiment of the present invention and coded at the time of recording or transmission is the terminal 240. Etc., where the encoded local maximum values of the partial signals corresponding to all the indexes are decoded, and then sent to the local maximum value buffer 243. It should be noted that, as described above, when the maximum value is not encoded when recording or transmitting the maximum value, the maximum value decoding circuit 242 is omitted,
The non-coded local maximum value is directly sent to the local maximum value buffer 243.

In the next maximum value detection circuit 244, the maximum value of all the maximum values stored in the maximum value buffer 243 is detected, and the maximum value is sent to the multiplier determination circuit 247. In addition, if there is a constraint such as the hardware scale, instead of directly obtaining the maximum value, a logical sum of all local maximum values may be obtained as an approximate value of the maximum value and replaced with this. Good.

Next, in the multiplier determining circuit 247, the maximum value supplied from the maximum value detecting circuit 244 by the corresponding maximum value in the maximum value buffer 243 corresponding to the index input via the terminal 245 or the like. By dividing the value, the multiplier for each sample data of the partial signal corresponding to the index is calculated. In addition,
Here, a power of 2 may be adopted as an approximate value of the multiplier, and multiplication of each sample data may be realized by bit-shifting each sample data.

Further, the reproduced signal (sample data) is supplied to the terminal 246, and this is the signal decoding unit 248.
Are stored in the input sample buffer 249 of In the next sample number determination circuit 250, the input sample buffer 2
For 49, it is determined whether or not the number of samples required for decoding is stored. The sample number determination circuit 25
When it is determined that the number of samples required for the decoding is stored in the input sample buffer 249 at 0, the sample data stored in the input sample buffer 249 is sent to the next signal decoding circuit 251. , Decrypted here. The time-series sample data obtained by the decoding of the signal decoding circuit 251 is sent to the time-series sample multiplying circuit 252.

When the signal is not encoded as described above, the input sample buffer 249,
The signal decoding unit 248 including the sample number determination circuit 250 and the signal decoding circuit 251 is omitted, and the reproduction input signal from the terminal 246 is directly sent to the time series sample multiplication circuit 252. Also, regarding the signal encoding and decoding methods, the present embodiment exemplifies the case where a certain number of samples are blocked and encoded, but the encoding is performed using a non-blocking operation such as a filter. The method may be adopted and is not particularly limited. Furthermore, the maximum value, the index, the input terminal to which the input signal is input, and the like may be performed by one or a plurality of terminals.

The time-series sample multiplication circuit 252 multiplies the multiplier from the multiplier determination circuit 247 and the time-series sample data from the signal decoding circuit 251, and the resulting time-series sample data (the above-mentioned multiplier is The multiplied time series sample data) is output to the signal output circuit 253. When the power of 2 is used as the multiplier as described above, the multiplication in the time-series sample multiplying circuit 252 can be performed by bit shifting.

The signal output circuit 253 outputs the multiplied time-series sample data to the terminal 254 and the like, and the process is completed.

Next, in FIGS. 3 and 4 described above,
Although the gain of the reproduction signal is digitally controlled, the present invention includes a case where similar processing is performed in an analog manner.

FIG. 5 shows a flow chart for explaining the operation when the level of the reproduction signal is controlled in an analog manner by the signal processing method of the present invention. The operation from step S51 to step S65 in FIG. 5 shows each step of the operation of controlling the signal level in an analog manner. Further, from step S51 to step S61, as in the case of steps S21 to S31 of FIG. 3, the maximum value among the maximum values of each partial signal is detected, and the maximum value is detected as the maximum value of each partial signal. Since the value is obtained by dividing the value, its description is omitted here.

In FIG. 5, in step S62,
The level is controlled in an analog manner according to the value obtained in step S61 similar to step S31 in FIG. In this case, the digital / analog (D
/ A) Performs processing for adjusting the reproduction level in the converted analog circuit configuration.

Here, in order to specifically realize step S62 as a configuration here, for example, when the signal attenuation is controlled by the variable resistance in the amplifier, the contact of the variable resistance is automatically set according to the value of p. It may be configured to move, but it is not particularly limited here.

In the next step S63, it is determined whether or not the index of the partial signal currently being reproduced has changed. If it is determined that the index has changed (YES), the process proceeds to the next step S64. On the contrary, if it is determined in step S63 that it has not changed (NO), the process returns to the same step S63 and the same operation is repeated until the index changes next.

In step S64, it is determined whether or not the processing has been completed for the partial signals of all indexes.
If it is determined that the processing has not ended (No), step S
Proceed to 65. In step S65, the process moves to the next index and the process from step S59 is repeated. On the other hand, if it is determined in step S64 that the processing has been completed for the partial signals of all indexes (Yes), the analog level control processing of FIG. 5 is completed.

As described above, in the signal processing method and apparatus of the present invention, when reproducing a real signal composed of a plurality of recorded or transmitted partial signals, each partial signal by the user at the time of reproduction is reproduced. It is possible to effectively switch the playback level while eliminating the playback level switching operation described above to reduce the burden on the user.

Next, referring to FIG. 6, as one specific example to which the signal processing apparatus for implementing the above-described signal processing method of the present invention is applied, for example, a digital audio signal is compression-encoded and recorded on a recording medium. 1 shows a schematic configuration of a compressed data recording / reproducing apparatus that expands and decodes a signal reproduced from.

In FIG. 6, the central processing unit (CPU) 90 performs control such as setting of the maximum value and gain control of the reproduced signal in the signal processing method of the above-described embodiment, and the maximum value encoding. The encoding process in the circuit 204 or the signal encoding unit 210 is performed in the encoder 63, for example, and the decoding process in the maximum value decoding circuit 241 or the signal decoding unit 248 is performed in the decoder 73, for example. Regarding the encoding and decoding of the maximum value,
The CPU 90 instead of the encoder 63 and the decoder 73
It is also possible to do in. Further, the digital gain control (gain adjustment) corresponding to the time series sample multiplication circuit 252 is performed by the multiplication circuit 78.
In, analog gain control (gain adjustment) is performed in the level adjustment circuit 77.

The compressed data recording / reproducing apparatus 9 shown in FIG.
First, as the recording medium, the spindle motor 5 is used.
A magneto-optical disk 1 which is rotationally driven by 1 is used. The magneto-optical disk 1 has, for example, a diameter of 6
A so-called mini disk (MD), which is a generic name for a 4 mm magneto-optical disk, can be used. At the time of recording data on the magneto-optical disk 1, so-called magnetic field modulation recording is performed by applying a modulation magnetic field according to the recording data with the magnetic head 54 while irradiating the optical head 53 with laser light, for example. Data is recorded along one recording track. At the time of reproduction, the recording track of the magneto-optical disk 1 is traced with laser light by the optical head 53 to perform magneto-optical reproduction.

The optical head 53 includes, for example, a laser light source such as a laser diode, a collimator lens, an objective lens,
It is composed of a polarization beam splitter, an optical component such as a cylindrical lens, and a photodetector having a light receiving portion of a predetermined pattern. The optical head 53 is provided at a position facing the magnetic head 54 through the magneto-optical disk 1. When recording data on the magneto-optical disk 1, a magnetic head 54 is driven by a head driving circuit 66 of a recording system to be described later to apply a modulation magnetic field according to the recording data, and at the same time, the optical head 53 is used for the purpose of the magneto-optical disk 1. By irradiating the track with laser light, thermomagnetic recording is performed by the magnetic field modulation method. Further, the optical head 53 detects the reflected light of the laser light applied to the target track, detects a focus error by, for example, a so-called astigmatism method, and detects a tracking error by, for example, a so-called push-pull method. When reproducing data from the magneto-optical disk 1, the optical head 53 detects the focus error and the tracking error, and at the same time, detects the difference in the polarization angle (Kerr rotation angle) of the reflected light of the laser light from the target track and reproduces it. Generate a signal.

The output of the optical head 53 is supplied to the RF circuit 55. The RF circuit 55 extracts the focus error signal and the tracking error signal from the output of the optical head 53 and supplies them to the servo control circuit 56, and binarizes the reproduction signal to reproduce the reproduction system decoder 7 described later.
Supply to 1.

The servo control circuit 56 is composed of, for example, a focus servo control circuit, a tracking servo control circuit, a spindle motor servo control circuit, a sled servo control circuit, and the like. The focus servo control circuit controls the focus of the optical system of the optical head 53 so that the focus error signal becomes zero. Further, the tracking servo control circuit controls the tracking of the optical system of the optical head 53 so that the tracking error signal becomes zero. Further, the spindle motor servo control circuit controls the spindle motor 51 so as to rotate the magneto-optical disk 1 at a predetermined rotation speed (for example, a constant linear speed). Further, the sled servo control circuit moves the optical head 53 and the magnetic head 54 to the target track position of the magneto-optical disk 1 designated by the system controller 57. The servo control circuit 56 that performs such various control operations sends information indicating the operating state of each unit controlled by the servo control circuit 56 to the system controller 57.

A key input operation section 58 and a display section 59 are connected to the system controller 57. The system controller 57 controls the recording system and the reproducing system in the operation mode designated by the operation input information from the key input operation unit 58. The system controller 7 also uses the optical head 53 and the magnetic head 5 based on the address information in sector units reproduced from the recording track of the magneto-optical disk 1 by the header time, the Q data of the subcode, or the like.
4 manages the recording position and the reproducing position on the recording track traced by 4. Further system controller 57
Controls the display unit 59 to display the reproduction time based on the data compression rate and the reproduction position information on the recording track. The system controller 57 is the CP
It is also possible to perform the processing in U90, in which case the CPU 90 need not be provided.

The above reproduction time display is the reciprocal of the data compression rate (absolute time information) with respect to the sector unit address information (absolute time information) reproduced from the recording track of the magneto-optical disk 1 by so-called header time or so-called subcode Q data. For example, in the case of 1/4 compression, the actual time information is obtained by multiplying by 4), and this is displayed on the display unit 59. Even at the time of recording, when absolute time information is recorded (pre-formatted) in advance on a recording track of a magneto-optical disk or the like, the pre-formatted absolute time information is read to determine the data compression rate. It is also possible to display the current position at the actual recording time by multiplying by the reciprocal.

Next, in the recording system of the recording / reproducing apparatus of this disc recording / reproducing apparatus, the analog audio input signal AIN from the input terminal 60 is supplied to the A / D converter 62 via the low-pass filter 61. This A / D converter 6
2 quantizes the analog audio input signal AIN. The digital audio signal obtained from the A / D converter 62 is an ATC (Adaptive Transform Coding) PC.
It is supplied to the M encoder 63. The digital audio signal of the A / D converter 62 is the CPU 90
Also sent to. At this time, the CPU 90 generates the index from the digital audio signal and sends it to the ATC encoder 63.

On the other hand, the input terminal 67 is supplied with, for example, a digital audio input signal DIN containing at least an index from another recording / reproducing apparatus, and this input signal DIN is passed through the digital input interface circuit 68 to the ATC encoder 63 and the ATC encoder 63. It is supplied to the CPU 90. At this time, the CPU 90 performs processing such as setting a maximum value corresponding to the above-described signal processing method at the time of recording of the present invention using the index and the digital audio signal, and obtains the obtained data from the ATC encoder 63.
Send to.

The encoder 63 quantizes the input signal AIN by the A / D converter 62 with respect to digital audio PCM data of a predetermined transfer rate and time-series sample data supplied through the digital input interface circuit 68. , Bit compression (data compression) is performed, the maximum value is also encoded, and these are sent to the memory 64. In the data compression by the encoder 63, the compression rate will be described as 4 times, but the present embodiment has a configuration that does not depend on this magnification and can be arbitrarily selected depending on the application example.

Next, in the memory 64, the writing and reading of data are controlled by the system controller 57, the ATC data supplied from the ATC encoder 63 is temporarily stored, and recorded on the disk as needed. It is used as a buffer memory for That is, for example, the compressed audio data that has been subjected to high-efficiency encoding by the ATC encoder 63 has a data transfer rate of 1/4 of the standard CD-DA format data transfer rate (75 sectors / sec), that is, 18. 7
It is reduced to 5 sectors / second, and this compressed data is continuously written in the memory 14. This compressed data (AT
As described above, it is sufficient to record one sector for every four sectors when it is compressed four times as described above. However, since recording every four sectors is practically impossible, it will be described later. It is designed to perform continuous sector recording. This recording bursts at a data transfer rate (75 sectors / second) same as that of the standard CD-DA format by using a cluster composed of a plurality of predetermined sectors (for example, 32 sectors + several sectors) as a recording unit through a pause period. Is done in a regular manner. That is, in the memory 14, 18.75 (= 75/4) corresponding to the bit compression rate.
AT written continuously at a low transfer rate of sectors / second
The C audio data is burst-read as recording data at the transfer rate of 75 sectors / sec. The overall data transfer rate of the read and recorded data, including the recording pause period, is as low as 18.75 sectors / sec, but within the time of the recording operation performed in bursts. The instantaneous data transfer rate in the above is the standard 75 sectors / sec. Therefore, when the disk rotation speed is the same as the standard CD-DA format (constant linear velocity), the same recording density and the same storage pattern as the annual Kai CD-DA format are recorded.

AT read out in burst from the memory 64 at the (instantaneous) transfer rate of 75 sectors / sec.
The C audio data or the like, that is, the recording data is supplied to the encoder 65. Here, in the data string supplied from the memory 64 to the encoder 65, the unit to be continuously recorded in one recording is a cluster composed of a plurality of sectors (for example, 32 sectors) and clusters arranged in front of and behind the cluster. There are several sectors for connection. This cluster connection sector is set longer than the interleave length in the encoder 65 so that the data of other clusters will not be affected even if interleaved.

The encoder 65, regarding the recording data supplied from the memory 64 in bursts as described above,
Encoding processing for error correction (parity addition and interleave processing), EFM encoding processing, and the like are performed. The recording data encoded by the encoder 65 is supplied to the magnetic head drive circuit 66. The magnetic head drive circuit 66 is connected to the magnetic head 54,
The magnetic head 54 is driven so as to apply the modulation magnetic field according to the recording data to the magneto-optical disk 1.

Further, the system controller 57 performs the above-mentioned memory control on the memory 64, and
By this memory control, the recording position is controlled so that the recording data read in burst from the memory 64 is continuously recorded on the recording track of the magneto-optical disk 1.
The recording position is controlled by controlling the recording position of the recording data which is burst-read from the memory 64 by the system controller 57 and outputting a control signal for designating the recording position on the recording track of the magneto-optical disk 1 to the servo control circuit. By feeding 56.

Next, the reproducing system of this magneto-optical disk recording / reproducing unit will be described. This reproducing system is for reproducing the record data continuously recorded on the recording track of the magneto-optical disk 1 by the above-mentioned recording system,
The decoder 71 is provided with a reproduction output obtained by tracing a recording track of the magneto-optical disk 1 with a laser beam by the optical head 53 and binarized and supplied by the RF circuit 55. At this time, not only the magneto-optical disk but also the so-called compact disk (CD: Compact Di
You can also read a read-only optical disc similar to sc).

The decoder 71 corresponds to the encoder 65 in the above-mentioned recording system, and performs the above-mentioned decoding processing for error correction and EFM decoding on the reproduction output binarized by the RF circuit 55. By performing processing such as processing, audio data and the like are reproduced at a transfer rate of 75 sectors / second, which is faster than the normal transfer rate. The reproduced data obtained by the decoder 71 is supplied to the memory 72.

In the memory 72, writing and reading of data are controlled by the system controller 57, and reproduction data supplied from the decoder 71 at a transfer rate of 75 sectors / second is written in bursts at the transfer rate of 75 sectors / second. Be done. In addition, in the memory 72, the reproduction data written in a burst at the transfer rate of 75 sectors / sec.
It is read continuously at sectors / second.

The system controller 57 writes the reproduced data in the memory 72 at a transfer rate of 75 sectors / second, and also writes the reproduced data from the memory 72 in the above 18.7.
Memory control is performed so that data is continuously read at a transfer rate of 5 sectors / second. Further, the system controller 57 performs the above-mentioned memory control on the memory 72, and continuously reproduces the above-mentioned reproduction data written in burst from the memory 72 from the recording track of the magneto-optical disk 1 by the memory control. Controls the playback position. This playback position is controlled by the system controller 5
By controlling the reproduction position of the reproduction data which is read out from the memory 72 in burst by 7 and supplying a control signal for designating the reproduction position on the recording track of the magneto-optical disk 1 or the optical disk 1 to the servo control circuit 56. Done.

ATC audio data obtained as reproduction data continuously read from the memory 72 at a transfer rate of 18.75 sectors / sec is ATC decoder 73.
Is supplied to. The ATC decoder 73 reproduces 16-bit digital audio data by decompressing (bit expanding) the audio ATC data four times, and also decodes the encoded maximum value. The digital audio data from the ATC decoder 73 is sent to the D / A converter 74 via the multiplication circuit 78 and also to the CPU 90, and further,
The maximum value and index data are also sent to the CPU 90.

At this time, the CPU 90 performs processing such as multiplier determination corresponding to the above-described signal processing method at the time of reproduction of the present invention by using the index, the maximum value and the digital audio data, and the obtained data is multiplied by the multiplication circuit. 78 and the level adjusting circuit 77. That is, when the gain control for the reproduced signal is performed digitally, a multiplier is sent to the multiplication circuit 78, and when it is performed analogly, a variable resistance control signal is sent to the level adjustment circuit 77.

Here, when the gain control is performed digitally, the CPU 9 is used by the multiplication circuit 78.
The multiplier data from 0 is multiplied, and the digital data which is digitally gain-controlled is sent to the D / A converter 74. The D / A converter 74 converts the digital audio data supplied from the ATC decoder 73 into an analog signal. The output of the D / A converter 74 is passed through a low pass filter 75 and a level adjusting circuit 77.
Is passed through as it is, and is output from the output terminal 76 as an analog audio signal AOUT which is digitally gain-controlled. It should be noted that in the configuration in which only this digital gain control is performed, the level adjustment circuit 7
7 becomes unnecessary. The output of the multiplication circuit 78 can also be output from the terminal 80 as a digital audio output signal DOUT via the digital output interface circuit 79.

Further, when the gain control is performed in an analog manner, the multiplication circuit 78 is not provided and the above A
The digital audio data from the TC decoder 73 is sent directly to the D / A converter 74, or the multiplication circuit 78
Is provided, the digital audio data from the ATC decoder 73 is multiplied by 1 as a multiplier and then sent to the D / A converter 74. This D /
The analog signal from the A converter 74 is sent to the level adjusting circuit 77 via the low-pass filter 75, and the level adjusting circuit 77 performs gain control based on the control signal from the CPU 90, and then the analog audio signal. It is output from the output terminal 76 as AOUT.

[0095]

As described above, according to the signal processing method and apparatus of the present invention, when recording or transmitting an actual signal composed of a plurality of partial signals, the maximum value of the signal level for each partial portion is determined. The maximum value of the partial signal to be reproduced is detected by comparing the maximum value of the maximum value of the maximum value with the maximum value of the partial signal to be reproduced at the time of reproduction. In the case of a small value, the level of the partial signal is automatically reproduced in accordance with the level of the maximum partial signal, so the user needs to perform the switching operation of the reproduction level for each partial signal. Therefore, it is possible to effectively switch the reproduction level while reducing the burden on the user. As a result, according to the signal processing method and apparatus of the present invention, it is possible to provide the user with a more comfortable use environment.

Further, according to the signal recording medium of the present invention, since the maximum value of the signal level for each partial signal is recorded together with the actual signal, the maximum value can be used for the level control during reproduction, Therefore, the user does not need to perform the reproduction level switching operation for each partial signal when reproducing the signal recording medium, and it is possible to effectively switch the reproduction level while reducing the burden on the user. Become.

[Brief description of drawings]

FIG. 1 is a flow chart showing an outline of an operation when recording or transmitting a signal by a signal processing method of the present invention.

FIG. 2 is a block circuit diagram showing a configuration of a main part of a signal processing apparatus of an embodiment of the present invention which records or transmits a signal by the signal processing method of the present invention.

FIG. 3 is a flowchart showing an outline of an operation when a signal is reproduced by the signal processing method of the present invention, particularly a flow of an operation when a reproduction level is digitally controlled.

FIG. 4 is a block circuit diagram showing a configuration of a main part of a signal processing apparatus of an embodiment of the present invention which reproduces a signal by the signal processing method of the present invention.

FIG. 5 is a flow chart showing an outline of an operation when a signal is reproduced by the signal processing method according to the present invention, and particularly showing a flow of an operation when the reproduction level is controlled in an analog manner.

FIG. 6 is a block circuit diagram showing a configuration of a compressed data recording / reproducing apparatus for digital audio signals as a specific example to which the signal processing apparatus of the embodiment of the present invention is applied.

[Explanation of symbols]

 201 Absolute value calculation circuit 203 Index determination circuit 204 Maximum value coding circuit 205 Maximum value output circuit 206 Maximum value zero clear circuit 207 Maximum value setting unit 208 Maximum value determination circuit 209 Maximum value substitution circuit 210 Signal coding unit 211,249 Input samples Buffer 212,250 Sample number determination circuit 213 Signal encoding circuit 214 Sample buffer zero clear circuit 215,253 Signal output circuit 242 Maximum value decoding circuit 243 Maximum value buffer 244 Maximum value detection circuit 247 Multiplier determination circuit 248 Signal decoding unit 251 signal Decoding circuit 252 Time series sample multiplication circuit

Claims (28)

[Claims] 1. A signal processing method of an actual signal composed of a plurality of partial signals, wherein a maximum value of a signal level for each partial signal of an actual signal composed of a plurality of partial signals is detected, A signal processing method characterized by recording or transmitting the above maximum value of. 2. The signal processing method according to claim 1, wherein a logical sum of absolute values of the partial signals is used as an approximate value of the maximum value. 3. The signal processing method according to claim 1, wherein the recorded or transmitted maximum value is encoded. 4. A signal recording medium, characterized in that a signal processed by using the signal processing method according to any one of claims 1 to 3 is recorded. 5. A signal processing method of an actual signal composed of a plurality of partial signals, in which a local maximum of the signal level of each partial signal of the actual signal composed of a plurality of partial signals is detected, and each partial together with the encoded actual signal is detected. A signal processing method comprising recording or transmitting the maximum value of a signal. 6. The signal processing method according to claim 5, wherein a logical sum of absolute values of the partial signals is used as an approximate value of the maximum value. 7. The signal processing method according to claim 5, wherein the recorded or transmitted maximum value is encoded. 8. A signal recording medium, wherein a signal processed by using the signal processing method according to any one of claims 5 to 7 is recorded. 9. A signal processing method for reproducing a signal recorded or transmitted by using the signal processing method according to claim 1 or 2, wherein reproduction of an actual signal composed of a plurality of partial signals recorded or transmitted. Prior to this, the maximum value among the maximum values at which the signal level of each partial signal was recorded or transmitted was detected, and the value obtained by dividing the detected maximum value by the maximum value of each partial signal A signal processing method characterized by multiplying each partial signal at the time of reproduction. 10. A signal processing method for reproducing a signal recorded or transmitted by using the signal processing method according to claim 3, wherein reproduction of an actual signal consisting of a plurality of partial signals recorded or transmitted is performed. , The encoded maximum value recorded or transmitted for the signal level of each partial signal is decoded, the maximum value among the decoded maximum values is detected, and the detected maximum value is A signal processing method characterized in that a value obtained by dividing a local maximum value of a partial signal is multiplied for each partial signal when reproducing an actual signal. 11. A signal processing method for reproducing a signal recorded or transmitted by using the signal processing method according to claim 5, comprising a plurality of encoded partial signals recorded or transmitted. Prior to the reproduction of the actual signal, the maximum value among the recorded maximum or maximum values of the signal level of each partial signal is detected, and the detected maximum value is divided by the maximum value of each partial signal. A signal processing method characterized by multiplying each decoded partial signal when reproducing an actual signal. 12. A signal processing method for reproducing a signal recorded or transmitted using the signal processing method according to claim 7, wherein the actual signal is composed of a plurality of encoded partial signals recorded or transmitted. Prior to the reproduction of, the encoded local maximum value at which the signal level of each partial signal is recorded or transmitted is decoded, and the maximum value among the decoded maximum values is detected, and the detected maximum value is detected. A signal processing method characterized in that a value obtained by dividing a maximum value by a local maximum value of each partial signal is multiplied for each partial signal decoded at the time of reproducing an actual signal. 13. The method according to claim 9, wherein a value of a power of 2 is used as an approximate value of a multiplier by which each of the partial signals is multiplied, and a bit shift is used as the multiplication.
The signal processing method according to claim 1. 14. A signal processing device for an actual signal composed of a plurality of partial signals, comprising detection means for detecting a maximum value of a signal level for each partial signal of the actual signal composed of a plurality of partial signals, At the same time, the signal processing apparatus records or transmits the maximum value of each partial signal. 15. The logical sum of absolute values of the partial signals is used as an approximate value of the maximum value.
4. The signal processing device according to 4. 16. The signal processing apparatus according to claim 14, further comprising an encoding means for encoding the recorded or transmitted maximum value. 17. A signal processing apparatus for an actual signal composed of a plurality of partial signals, comprising detection means for detecting a maximum value of a signal level for each partial signal of an actual signal composed of a plurality of partial signals, and encoded. A signal processing device characterized by recording or transmitting the maximum value of each partial signal together with an actual signal. 18. The logical sum of absolute values of the partial signals is used as an approximate value of the maximum value.
7. The signal processing device according to 7. 19. The signal processing apparatus according to claim 17, further comprising an encoding means for encoding the recorded or transmitted maximum value. 20. A signal processing device for reproducing a signal recorded or transmitted by using the signal processing method according to claim 1 or 2, wherein the reproduction of an actual signal composed of a plurality of partial signals recorded or transmitted. Prior to the above, detection means for detecting the maximum value among the maximum values at which the signal level of each partial signal is recorded or transmitted, and a value obtained by dividing the detected maximum value by the maximum value of each partial signal, A signal processing device, comprising: a multiplication means for multiplying each partial signal when reproducing an actual signal. 21. A signal processing device for reproducing a signal recorded or transmitted by using the signal processing method according to claim 3, wherein reproduction of an actual signal composed of a plurality of partial signals recorded or transmitted is performed. , Detecting means for decoding the coded local maximum value recorded or transmitted for each partial signal and detecting the maximum value among the decoded local maximum values, and the detected maximum value. A signal processing apparatus, comprising: a value obtained by dividing the value by the maximum value of each partial signal, and a multiplication means for multiplying the value for each partial signal when reproducing the actual signal. 22. A signal processing device for reproducing a signal recorded or transmitted by using the signal processing method according to claim 5 or 6, comprising a plurality of encoded partial signals recorded or transmitted. Prior to the reproduction of the actual signal, the detection means for detecting the maximum value among the maximum values at which the signal level of each partial signal is recorded or transmitted, and the detected maximum value is divided by the maximum value of each partial signal. And a multiplication means for multiplying the obtained value for each partial signal decoded at the time of reproducing the actual signal. 23. A signal processing device for reproducing a signal recorded or transmitted by using the signal processing method according to claim 7, wherein the signal is a real signal composed of a plurality of encoded partial signals recorded or transmitted. Prior to the reproduction of, the signal level recording or transmission of each partial signal is decoded to decode the encoded maximum value, the detection means for detecting the maximum value among the respective decoded maximum value, A signal processing apparatus, comprising: a multiplication unit that multiplies a value obtained by dividing the detected maximum value by a local maximum value of each partial signal for each partial signal decoded at the time of reproducing an actual signal. 24. The value of a power of 2 is used as an approximate value of a multiplier by which the partial signal is multiplied, and a bit shift is used as the multiplication.
The signal processing device according to claim 1. 25. A signal processing apparatus for reproducing a signal recorded or transmitted by using the signal processing method according to claim 1, 2, 5, or 6, comprising a plurality of partial signals recorded or transmitted. Prior to the reproduction of the actual signal, the control means is provided with a maximum value at which the signal level of each partial signal is recorded or transmitted, and the control means detects the maximum value among the maximum values. Then
A signal processing device characterized in that a reproduction level is controlled in an analog manner for each partial signal at the time of reproducing an actual signal according to a maximum value and a maximum value of each partial signal. 26. A signal processing apparatus for reproducing a signal recorded or transmitted by using the signal processing method according to claim 3 or 7, wherein an actual signal composed of a plurality of partial signals recorded or transmitted is reproduced. Prior to the above, there is provided a control means to which the encoded maximum value, which is the recording or transmission of the signal level for each partial signal, is supplied, and the control means decodes the maximum value, and Signal processing characterized by detecting the maximum value among the maximum values and controlling the reproduction level in an analog manner for each partial signal when reproducing the actual signal according to the maximum and maximum values of each partial signal apparatus. 27. A signal processing apparatus for reproducing a signal recorded or transmitted by using the signal processing method according to claim 1, 2, 5, or 6, comprising a plurality of partial signals recorded or transmitted. Prior to the reproduction of the actual signal, detection means for detecting the maximum value at which the signal level of each partial signal is recorded or transmitted and the maximum value among the maximum values, and the detection output of the detection means are supplied. And controlling the reproduction level in an analog manner for each partial signal at the time of reproducing the actual signal according to the maximum value and the maximum value of each partial signal. Signal processing device. 28. A signal processing device for reproducing a signal recorded or transmitted by using the signal processing method according to claim 3 or 7, wherein an actual signal composed of a plurality of partial signals recorded or transmitted is reproduced. Prior to the above, the decoding means for decoding the coded local maximum value at which the signal level of each partial signal is recorded or transmitted, and the maximum value among the respective local maximum values are output from the output of the decoding means. It has a detection means for detecting and a control means to which the detection output of the detection means is supplied, and the control means is provided for each partial signal at the time of reproducing the actual signal according to the maximum value and the maximum value of each partial signal. A signal processing device characterized in that the reproduction level is controlled in an analog manner.