JPH10255399A - Audio reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound field adjusting function without increasing cost and size of the device. SOLUTION: This device is for reproducing an audio data from a disk recording medium, and is equipped with a buffer memory 35 for preventing a sound skip due to a track jump of a pickup and a memory control means for controlling the read and write of this buffer memory 35. The buffer memory 35 is equipped with memory areas 353L and 353R used for adjusting a sound field for a left channel and a right channel respectively. The memory control means 34 is provided with time difference storage means 62L and 62R capable of storing read-out time differences of the left channel and the right channel from the audio data. The audio data of the left channel from the memory area 353L and the audio data of the right channel from the memory area 353R are read out with the time differences stored in the time difference storage means by the memory control means 34.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an audio reproducing apparatus for reproducing audio data from a disk recording medium such as a (compact disk).

[0002]

2. Description of the Related Art An audio reproducing apparatus of this kind is usually capable of reproducing two channels of a left channel and a right channel. The left channel audio signal is output from a left channel speaker, and the right channel audio signal is output. Sound is emitted from the right channel speaker.

[0003] By the way, the listener of the reproduced sound (listener)
If the distance from the position to the position of the left and right channel speakers is not equal, the sense of localization for the listener is impaired. However, in a vehicle-mounted audio reproducing apparatus, the distance from the driver as a listener to the positions of the left and right channel speakers cannot be equal. In addition, for example, a so-called mini-component as an audio playback device must be placed in a corner of a room due to space and the like, and the distance from the listener to the positions of the left and right channel speakers may be equal. If not, it often happens.

Therefore, conventionally, according to the difference in the distance from the listener to the positions of the left and right channel speakers,
By providing a time difference in the reproduction timing between the left channel sound and the right channel sound, a sense of localization similar to the case where the distance from the listener to the positions of the left and right channel speakers is equal is obtained. An audio playback device having a sound field adjustment function is provided.

In a conventional audio reproducing apparatus, the sound field adjusting function is realized by using a DSP (digital signal processor) and a memory such as a DRAM external to the DSP.

That is, the DSP temporarily stores the reproduced audio data in the DRAM, and stores the left channel audio data and the right channel audio data from the DRAM with a time difference corresponding to the adjustment value of the listener. , Work to read each.

[0007]

As described above, conventionally, in order to realize the sound field adjusting function, a DSP and an external memory were required, so that a board area for the DSP and an external memory were required. However, miniaturization of the apparatus has been a major constraint. There is also a problem that the cost is increased by the amount of the DSP and the memory. These are serious problems particularly in an audio reproducing apparatus mounted on a vehicle.

[0008] It is an object of the present invention to provide an audio reproducing apparatus with a sound field adjusting function, which solves the above-mentioned drawbacks.

[0009]

In order to solve the above problems, an audio reproducing apparatus according to the present invention is an apparatus for reproducing audio data from a disk recording medium,
A buffer memory for correcting an error in a reproduction position of a pickup for extracting the audio data from the disk and correcting discontinuity of audio data extracted from the disk recording medium; and reading and writing of the buffer memory. In the audio playback device comprising a memory control means for controlling, the buffer memory,
A memory area for a left channel and a memory area for a right channel for sound field adjustment are provided, and a read time difference between left channel audio data and right channel audio data can be stored in the memory control means. A time difference storage means, the memory control means, the left channel audio data from the left channel memory area of the buffer memory, the right channel audio data from the right channel memory area, It is characterized in that it is read out with the time difference stored in the time difference storage means.

In the audio reproducing apparatus according to the present invention having the above-described configuration, when an error in the reproduction position occurs due to a track jump of the pickup or the like, the reproduction audio data is returned for the time required to return the reproduction position of the pickup to the correct position. It has a buffer memory for buffering.

According to the present invention, a left channel memory area and a right channel memory area are provided as a part of the buffer memory, and the left channel audio data and the right channel A time difference storage means capable of storing a read time difference between the audio data of the channel and the audio data of the channel is provided. Then, by the memory control means, the left channel audio data from the left channel memory area for sound field adjustment, which is a part of the buffer memory, and the right channel audio data from the right channel memory area, The sound field adjustment is performed by reading with the time difference stored in the time difference storage means.

As described above, according to the present invention, it is used as audio data for sound field adjustment of a partial area of an existing memory, and the memory control means performs sound field adjustment as described above. Additional processing functions,
A conventional DSP and memory are not required, so that downsizing and cost reduction can be realized as compared with the conventional device.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of an audio reproducing apparatus according to the present invention will be described below with reference to the drawings.

An example described below is an example in which the present invention is applied to an audio recording / reproducing apparatus using an optical disk smaller than a CD, capable of recording and reproducing an audio signal.

[Description of Configuration of Recording / Reproducing Apparatus] FIG. 2 shows a configuration of an optical disk recording / reproducing apparatus to which the present invention is applied. In FIG. 2, reference numeral 1 denotes a disk cartridge. The disk cartridge 1 is configured by storing an optical disk 1B having a diameter of 64 mm in a cartridge body 1A. The optical disc 1B includes a read-only optical disc, a recordable magneto-optical disc, and a hybrid disc in which a read-only area and a recordable area are mixed.
There are different types. In the following description, an example in which the optical disk 1B is a magneto-optical disk will be described.

A spiral pre-groove for controlling the tracking of a light beam is previously formed on the optical disk 1B. In particular, in this example, the pre-groove is FM-modulated and recorded based on absolute address data. Have been. Therefore, the pre-groove of the optical disc 1B is
It is meandering in the radial direction of the optical disc 1B based on the absolute address data.

The optical disk 1B is rotated by a spindle motor 2. The rotation of the spindle motor 2 is controlled by the servo control circuit 5 so that the disk 1B rotates at a constant linear velocity. The cartridge body 1A is provided with a shutter. When the disc cartridge 1 is placed on the disc mounting tray and loaded in the apparatus, the shutter is opened, and the optical disc 1B is externally opened through the opening of the cartridge body 1A. You are ready to face. When the disc cartridge 1 is ejected from the apparatus, the shutter moves to a position where the opening of the cartridge main body 1A is closed. And disk 1
A magnetic head 3 for recording is provided above the shutter opening of B.
The optical pickup 4 is disposed to face the lower part of the shutter opening of the cartridge body 1A.

The movement of the optical pickup 4 in the radial direction of the disk 1B is controlled by a feed motor 6. Further, the servo control circuit 5 performs focus control and tracking control of the optical pickup 4.

The system controller 20 is equipped with a microcomputer and manages the entire operation. The system controller 20 is supplied with a key input signal from the key group 10. This key group 10
Is provided on the front panel surface of the recording / reproducing device.
Power key, eject key, play key, pause key,
A stop key, a record key, a fast forward playback key, a rewind playback key, and the like are provided.

Further, on the front panel surface of the recording / reproducing apparatus,
A variable input unit 50 is an example of a sound field adjustment value input unit for setting a reproduction (reading) time difference between the left and right channels.
Is provided. As shown in FIG. 1, the variable input unit 50 uses a slide volume 50 as shown in FIG. 1, and operates a slide knob 50a of the slide volume to move the position, thereby obtaining a read time difference between the left and right channels. Can be set.

For example, when the knob 50a of the slide volume 50 is at the center position, the read time difference between the left and right channels is zero, and when the knob 50a is moved to the left, the data of the right channel is changed with respect to the data of the left channel. When the knob 50a is moved to the right, the data of the left channel is read and reproduced with a delay corresponding to the amount of movement when the knob 50a is moved to the right. Is set to

In this case, the slide volume 50 has a resistance value corresponding to the position of the knob 50a, a voltage corresponding to the resistance value is obtained, and a value obtained by A / D conversion of this voltage is supplied to a system controller 20 described later. Is done.

For this purpose, an A / D converter is provided between the variable input unit 50 and the system controller 20 as necessary, and A / D converts a voltage corresponding to the resistance value of the slide volume 50. System controller 20
However, in the case where the microcomputer is configured with an A / D converter, the A / D converter connected between the variable input unit 50 and the system controller 20 is omitted.

Then, the system controller 20 converts the voltage value corresponding to the resistance value of the slide volume 50 into information on the read time difference between the left and right channels as described above. Then, the information of the read time difference is stored in the internal memory of the system controller 20.

The system controller 20 is constituted by a microcomputer. System controller 2
0 manages and controls the operation of the recording and reproducing apparatus by generating a control signal based on the operated key in the key group 10 and supplying the generated control signal to each section of the recording and reproducing apparatus.

The system controller 20 is connected to a display 30 such as an LCD or a fluorescent display tube. The display 30 shows the total playing time of the loaded optical disc 1B, the elapsed time of the music being played,
Time information such as the remaining performance time of the music being played, the remaining performance time of the entire music, and the track number of the music being played are displayed. For a disc on which a disc name or track name is recorded, the disc name or track name is displayed. Further, if the recording date and time of the music or the disc is recorded, the recording date and time are displayed.

The configuration of the recording / reproducing signal system shown in FIG. 2 has been devised so that the configuration can be simplified as much as possible by using an integrated circuit. Note that the mode of each unit is switched between a recording mode and a reproducing mode by a mode switching signal from the system controller 20.

[Explanation of Recording Operation] Reference numeral 31 denotes an input terminal for an audio signal (one channel is shown for simplicity in the figure, but it is actually a two-channel stereo, the same applies hereinafter). The audio signal from the input terminal 31 is
In the A / D converter 32, the sampling frequency 4
It is digitized at 4.1 kHz and the number of quantization bits is 16 bits.

This digital audio signal is supplied to an audio compression encoding / decoding circuit 33. In the audio compression encoding / decoding circuit 33, the audio signal is data-compressed to about 1/5. In this case, as a compression technique of the audio signal, for example, a modified DCT (Modified
screate Cosine Transform) is used.

The audio signal compressed by the audio compression encoding / decoding circuit 33 is supplied to a memory controller 34.
Is once stored in a buffer memory 35 controlled by the memory controller 34. In this example, a DRAM having a data capacity of, for example, 4 Mbits is used as the buffer memory 35.

The memory controller 34 controls the buffer memory 3 if the track jump, in which the recording position on the optical disk 1B jumps due to vibration or the like during the recording operation, does not occur.
5, the compressed data is sequentially read out at a transfer speed approximately five times the write speed, and the read data is transferred to the data encode / decode circuit 36 having a sector structure.

When detecting that a track jump has occurred during recording, the memory controller 34 stops the data transfer to the data encoding / decoding circuit 36, and the compressed data from the audio compression encoding / decoding circuit 33. Is stored in the buffer memory 35. Thereafter, when the irradiation position of the light beam emitted from the optical pickup 4, that is, the recording position is corrected, the buffer memory 3
The memory controller 34 controls the writing and reading of the memory 35 so as to restart the data transfer from 5 to the data encoding / decoding circuit 36.

The detection of whether or not a track jump has occurred can be performed, for example, by providing a vibrometer in the recording / reproducing apparatus and detecting whether or not the magnitude of the vibration is such that a track jump occurs. . As described above, since the absolute address data is recorded in the pregroove on the disk 1B of this example, the absolute address data is read at the time of recording, and the continuity of the decoded address data is determined by the system controller 20. By monitoring, a track jump can be detected. Alternatively, a track jump may be detected by taking the OR of the absolute address data with the vibrometer. When a track jump occurs, the system controller 20 controls the optical pickup 4 so that the power of the light beam from the optical pickup 4 for magneto-optical recording is reduced to a level at which recording is not possible, or the power is reduced to zero. Things.

The correction of the recording position when a track jump occurs is performed using the above-mentioned absolute address data. Further, as understood from the above, the data capacity of the buffer memory 35 in this case is a capacity capable of accumulating compressed data corresponding to the time from the occurrence of a track jump to the correct correction of the recording position. Is the minimum requirement. In this example, the buffer memory 35 has a capacity of 4 M bits as described above, and this storage capacity is selected as having a sufficient margin to sufficiently satisfy the above conditions.

In this case, the memory controller 34
During the normal operation during the recording, the memory control is performed so that the data stored in the buffer memory 35 is reduced as much as possible. That is, when the data amount of the buffer memory 35 becomes equal to or more than a predetermined amount, a predetermined amount of data, for example, 32 sectors (one sector is 1 CD-byte)
Only the data of the ROM sector (about 2 Kbytes) is read from the buffer memory 35, and the memory control is performed such that a write space of a predetermined data amount or more is always secured.

The data encoding / decoding circuit 36
The data read from the buffer memory 35 is stored in a CD-R
Encode to data of OM sector structure. As will be described later, the recording and reproduction of the audio data is performed in units of 32 sectors of audio data (about 2 seconds of the original analog audio signal, but about 0.4 seconds due to data compression). Is what you do. The audio data for 32 sectors is hereinafter referred to as a cluster.

The output data of the data encoding / decoding circuit 36 is supplied to an EFM and CIRC encoding / decoding circuit 37. In this circuit 37, the data is subjected to encoding processing for error detection and correction, and modulation processing suitable for recording, in this example, EFM (8-14 modulation) processing. In this example, a code for error detection and correction is used in which the interleave is changed from CIRC (Cross Interleave Reed-Solomon Code) of a compact disc. The recording data is intermittent data, and before and after the audio data of 32 sectors as one cluster, a total of four sectors (hereinafter, referred to as linking sectors) for cluster connection (including one sub data sector) are provided. It is added to form unit recording data consisting of 36 sectors.

The recording data thus formed is:
It is supplied to the recording magnetic head 3 via the head drive circuit 38. As a result, a magnetic field modulated by the recording data is applied to the disk 1B (magneto-optical disk).

The laser beam from the optical pickup 4 is applied to the disk 1B. At the time of recording, the recording track is irradiated with a laser beam having a constant power larger than that at the time of reproduction. By this light irradiation and the modulation magnetic field by the magnetic head 3, data is recorded on the disk 1B by thermomagnetic recording. Thus, data of about 2 seconds (1 cluster) of the original audio signal is recorded on the disk 1B in about 0.4 seconds.

The magnetic head 3 and the optical pickup 4 are configured so as to be able to move in the radial direction of the disk 1 in synchronization with each other.

Reference numeral 39 denotes an RF amplifier to which a detection output signal from a photodetector of the optical pickup 4 is supplied. The RF amplifier 39 generates an RF signal as a reproduction signal of the optical disc 1B based on an output signal from a photodetector of the optical pickup 4. When the optical disk 1B is a magneto-optical disk, based on the difference in the Kerr rotation angle of the light beam reflected by the recording film of the optical disk 1B,
An RF signal is output from the RF amplifier 39. This RF signal is supplied to the EFM and CIRC encoding / decoding circuit 37.
Supplied to

The RF amplifier 39 generates a focus error signal from the output signal of the photodetector based on the so-called astigmatism method. Further, the RF amplifier 39 generates a tracking error signal from a detection output of the photodetector by a so-called three-spot method. Further, the RF amplifier 39 generates a signal in which a pregroove is detected by a so-called push-pull method, that is, a push-pull signal, and supplies the signal to an address decoder 40 described later.

The generated focus error signal and tracking error signal are supplied to the servo control circuit 5 as described above. The RF amplifier 39 extracts a clock component from the generated RF signal and supplies the clock component to the servo control circuit 5. The servo control circuit 5 compares the clock component with a reference clock to generate a spindle servo signal, and supplies the spindle servo signal to the spindle motor 2. As a result, the spindle motor 2 is controlled so as to rotate the disk at a constant linear velocity.

The address decoder 40 generates address data by FM demodulating the push-pull signal supplied thereto. The address data demodulated by the address decoder 40 is supplied to the EFM and CIRC encoding / decoding circuit 37, where the address data is decoded. The decoded address information is supplied to the system controller 20, and is used for recognition of the recording position of the recording and position control. The address information is used for recognizing the reproduction position and controlling the position even during reproduction.

At the time of this recording, the address data decoded by the EFM and CIRC encoding / decoding circuit 37 is inserted into the recording data and recorded on the disk.

[Explanation at the time of reproduction] Next, the time of reproduction will be described. That is, at the time of this reproduction, the spindle motor 2 is controlled by the servo control circuit 5 in the same manner as at the time of recording.
The rotation speed of the disk 1 is controlled at the same linear speed as during recording by a signal from the pregroove.

At the time of reproduction, as described above, the optical pickup 4 detects the focus error by the astigmatism method by detecting the reflected light of the laser beam applied to the target track, and performs the tracking by the push-pull method. An error is detected, and a difference in the polarization angle (Kerr rotation angle) of the reflected light from the target track is detected, and a reproduced RF signal is output.

The output of the optical pickup 4 is supplied to the RF amplifier 3
9. The RF amplifier 39 includes the optical pickup 4
A focus error signal and a tracking error signal are extracted from the output of (1) and supplied to the servo control circuit 5, and the reproduction signal is binarized and supplied to the EFM and CIRC encoding / decoding circuit 37.

The servo control circuit 5 controls the focus of the optical system of the optical pickup 4 so that the focus error signal becomes zero, and controls the optical system of the optical pickup 4 so that the tracking error signal becomes zero. Perform tracking control.

The output of the RF amplifier 39 is supplied to an address decoder 40, which extracts and decodes absolute address data from the pregroove. Then, the absolute address data from the decoder 40 is supplied to the system control circuit 20 via the circuit 37, and is used by the servo control circuit 5 for controlling the reproduction position of the optical pickup 4 in the disk radial direction. Also, the system control circuit 20
Address information in sector units extracted from the reproduction data can also be used to manage the position on the recording track where the optical pickup 4 is scanning.

At the time of this reproduction, as will be described later,
The compressed data read from B is written to the buffer memory 35 and read and decompressed. However, due to the difference in transmission rate between the two data, the data read from the disk 1B by the optical pickup 4 is performed, for example, using the buffer memory 3
5 is performed intermittently so that the data stored in 5 does not become less than a predetermined amount.

In the EFM and CIRC encoding / decoding circuit 37, the signal supplied via the RF amplifier 39 is EFM demodulated and subjected to error correction processing. The output of the EFM and CIRC encoding / decoding circuit 37 is supplied to a sector-structured data encoding / decoding circuit 36, which deciphers the sector structure of the CD-ROM and decodes the data into compressed original data.

The output of the data encoding / decoding circuit 36 is temporarily stored in the buffer memory 35 via the memory controller 34. And the memory controller 3
Reference numeral 4 indicates that the compressed data from the data encoding / decoding circuit 36 is sequentially transferred at a transfer rate of about 1/5 of the writing speed unless a track jump in which the reproduction position jumps due to vibration or the like during the reproduction occurs. Reads the read data and converts the read data into an audio compression encode / decode circuit 33
Transfer to In this case, the memory controller 34 controls the writing and reading operations of the buffer memory 35 so that the amount of data stored in the buffer memory 35 does not fall below a predetermined value.

When it is detected that a track jump has occurred during reproduction, the memory controller 34 stops writing data from the data encoding / decoding circuit 36 to the buffer memory 35, and outputs the audio compression encoding / decoding circuit. Only the data transfer to S.33 is performed. Then, when the irradiation position of the light beam emitted from the optical pickup 4, that is, the reproduction position is corrected, the memory controller 34 restarts the data writing from the data encoding / decoding circuit 36 to the buffer memory 35. Write and read control of the memory 35 is performed.

As described above, the memory controller 34 controls the memory so that a predetermined minimum amount of predetermined data is stored in the buffer memory 35 as much as possible during a normal reproduction operation. For example, the buffer memory 35
When the data amount becomes equal to or less than a predetermined amount, a control signal is sent to the system controller 20 to intermittently take in data from the disk 1B by the optical pickup 4, and the data from the data encoding / decoding circuit 36 Data writing is performed, and memory control is performed so that data of a predetermined data amount or more is always kept in the memory.

The time required to fully read data into the buffer memory 35 is about 0.9 seconds, and this data corresponds to an analog audio signal of about 3 seconds.
That is, when the buffer memory 35 is full of data, even if the signal on the disk 1B cannot be read, it is possible to continue outputting the reproduction signal for about 3 seconds. In the meantime, the optical pickup is re-accessed to the original position and the signal is read again, so that the occurrence of sound skipping can be prevented.

The digital data decompressed by the audio compression encoding / decoding circuit 33 is supplied to the D / A converter 4.
1 and converted back to an analog signal. This analog signal is output from the output terminal 42.

The above is the basic configuration of the recording / reproducing apparatus of this example. In the present invention, in particular, the memory controller 34 and the buffer memory 35 are configured as shown in FIG. 1 for the sound field adjustment function.

FIG. 1 shows a more detailed configuration of the memory controller 34 and the buffer memory 35 in this embodiment and their peripheral portions.

That is, in this case, the buffer memory 35 stores the user TOC area 3 as a memory area.
51, data area 352, sound field adjustment area 353
Is provided. The sound field adjustment area 353 includes an area 353L for the left channel and an area 353 for the right channel.
R.

The memory controller 34 is provided with a time difference storage means 60 in addition to the memory control section 340. The time difference storage means 60 includes a left channel read address setting counter 61L and its preset value register 62L, and a right channel read address setting counter 61R and its preset value register 62R.

The count value of the counter 61L indicates an address pointer position for reading left channel audio data from the left channel area 353L.
The counter 61L counts, for example, a clock from the memory control unit 340 and increments the count value. Similarly, the count value of the counter 61R indicates the address pointer position for reading the left channel audio data from the right channel area 353R,
The counter 61R counts a clock from the memory control unit 340, for example, and increments the count value.

In this case, the counter 61L and the counter 61R are provided in the preset value register 62, respectively.
The counting is started from the count values set in L and 62R.

A count value corresponding to the read time difference between the left channel and the right channel is set in the preset value registers 62L and 62R from the system controller 20. These count values are calculated by the system controller 20 from the information of the read time difference stored in the built-in memory, and are stored in the preset value register 62 through the bus 71.
L, 62R. Alternatively, the system controller 20 sends the information of the read time difference stored in the internal memory to the memory control unit 340, and the memory control unit 340
From the received information of the time difference, the preset value register 62
It is also possible to calculate and set a preset value to be set for L and 62R.

The memory control unit 340 has the data area 35
2 stores the data received from the encode / decode circuit 36, and then receives a data output request from the audio compression encode / decode circuit 33, and transfers the data in the data area 352 through the bus 72 to the audio compression encode / decode circuit. Send to 33. The data decoded and decompressed by the audio compression encoding / decoding circuit 33 is stored again in the sound field adjustment area 353 by the memory control unit 340 via the bus 72.
Until this stage, there is no read time difference between the left and right channels, and as shown in FIG.
3, data of two channels at the same sampling point is written as a set.

In FIG. 3, L0, L1, L2,.
... are sample data of the left channel, and R0, R
1, R2... Are sample data of the right channel.
The numbers following L and R indicate the sampling points, and those at the same sampling point are shown as the same numbers.

Then, the memory control unit 340 stores the data written in the sound field adjusting area 353 in the counter 61.
In accordance with the read address pointers of the sound field adjustment areas 353L and 353R indicated by L and the count value of the counter 61R, the data is read and supplied to the D / A converter 41 through the bus 72 and the audio interface 73.

At this time, as shown in FIG. 3B, the data of the left channel is equal to the difference between the preset value of the preset value register 62L and the preset value of the preset value register 62R.
There is a time difference between the read data and the right channel data. In the example of FIG. 3B, a time difference of 5 samples is provided between the left and right channel data. This time difference is set by the listener using the slide volume 50 as described above. In other words, the listener adjusts the slide volume 50 to set the playback time difference between the left and right channels, adjust the sound field,
Adjustment can be made so as to obtain a proper sense of localization according to the listening position.

FIG. 4 is a flowchart showing a processing routine of the operation of the memory control unit 340 at this time.

As described above, in this embodiment, a partial area of the buffer memory 35 for preventing sound skipping, which is existing in the apparatus, is provided without providing a special memory or DSP for sound field adjustment. The sound field adjustment function can be realized by making a slight change to the memory controller that controls the reading and writing of the buffer memory 35 while using it. Therefore, even if the sound field adjusting function is added, the cost of the device can be prevented from increasing, and the device does not increase in size because no separate memory or DSP space is required.

The above is a case where the present invention is applied to a reproducing system of a recording / reproducing apparatus using a small optical disk.
Of course, the present invention can also be applied to a CD player having a buffer memory for preventing sound skipping and its memory controller.

[0072]

As described above, according to the present invention, even if a sound field adjusting function is added, the cost of the apparatus can be prevented from increasing, and the space for a separate memory and DSP is not required. The audio device does not increase in size.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an embodiment of an audio reproduction device according to the present invention.

FIG. 2 is an overall block diagram of a recording / reproducing device as an example of a device to which the present invention is applied;

FIG. 3 is a timing chart for explaining the operation of the embodiment of the present invention;

FIG. 4 is a diagram showing an example of a flowchart of an operation of a main part of the embodiment of the present invention.

[Explanation of symbols]

1B: optical disk, 4: optical pickup, 33: audio compression encoding / decoding circuit, 34: memory controller, 35: buffer memory, 36: data encoding / decoding circuit of sector structure, 37: EFM and CIR
C encode / decode circuit, 38 ... head drive circuit,
39: RF amplifier, 61L, 61R: Counter, 62
L, 62R: preset value register, 340: memory control unit, 351: TOC area, 352: data area,
353L: Memory area for left channel for sound field adjustment, 353R: Memory area for right channel for sound field adjustment

Claims (2)

[Claims] 1. An apparatus for reproducing audio data from a disk recording medium, comprising: a buffer memory for correcting discontinuity of audio data extracted from the disk recording medium; and a controller for controlling reading and writing of the buffer memory. An audio playback device comprising: a memory control unit that performs a time adjustment; a left channel memory area and a right channel memory area for time adjustment; and a left channel audio data for the memory control unit. And a time difference storage means capable of storing a read time difference between the audio data of the right channel and the audio data of the left channel from the memory area for the left channel of the buffer memory. Memory area for right channel And audio data of the right channel, the time difference with the time difference stored in the storage means, an audio reproducing apparatus, characterized in that the read out. 2. The apparatus according to claim 1, further comprising setting means for setting the time difference stored in the time difference storing means, wherein a read time difference between the left channel audio data and the right channel audio data can be adjusted. The audio reproducing device according to claim 1, wherein