JP2000207844A - Start control device of atrac decorder in md player - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent such a situation that takes a long time to obtain a final voice signal caused by the setting of stored data quantity or that takes a long time to obtain a final voice signal and generates a sound cut even if reading parts of this time and the next time are positioned at separated points physically. SOLUTION: A reading head 6, a memory 7, an ATRAC(adaptive transform acoustic coding) decoder 8, a this time reading part detecting circuit 9, a next time reading part detecting circuit 10 are connected to a CPU 5 through a bus bar. A start control circuit 11 performing start of the ATRAC decoder 8 and a start of output of the memory 7 corresponding to a time required for search obtained by the this time reading part detecting circuit 9 and the next time reading part detecting circuit 10 is connected to the CPU 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an activation control device for an ATRAC decoder in an MD player,
The recording part of the ATRAC audio compression data recorded on the MD is intermittently read by the read head, temporarily stored in the memory, and the stored data is intermittently taken out to obtain the ATRAC.
The present invention relates to an ATRAC decoder activation control device in an MD player that can input to an AC decoder and obtain a predetermined digital audio signal or analog signal.

[0002]

2. Description of the Related Art A recording medium called an MD (mini disk) is a disk having a diameter which is about half the diameter of a widely used CD (compact disk).
The available recording time is based on audio compression technology (ATRAC: Adapti
ve Transform Acoustic Coding), which is almost the same as a CD, and also provides high quality sound quality comparable to a CD in sound quality.

Also, unlike the CD, the MD is housed in a cartridge, so that it is easy to handle without fingerprints or scratches. Also, the jump of the music track can be performed quickly as in the case of the CD, and the usability is very good. In addition, because of the high sound quality as described above, it has been widely used with a tendency to replace conventional analog cassette tapes.

A conventional M for reproducing such an MD is used.
The D player has a read head 2, a memory 3, and an ATRAC via a bus bar (not shown) to a CPU 1 for controlling the entire MD player, as shown in FIG. Decoder 4
Are connected to perform a complex operation.

That is, the reading head 2 is an MD (not shown)
This is for reading signals with an optical pickup arranged opposite to the recording surface of the optical pickup. The focus error signal and the tracking error signal necessary for controlling the just focus and just tracking of the optical pickup, and the address information of the MD recording area. Servo, EFM (8-14 modulation) and ACIRC of a certain ADIP FM signal
(Code error correction).

A read signal read from the MD by the read head 2 under the control of the CPU 1 and subjected to EFM and ACIRC signal processing is temporarily stored in the memory 3 and then taken out and input to the ATRAC decoder 4. Is done.

The ATRAC decoder 4 compresses an audio signal and expands the recorded data to its original state. The audio compression during recording is usually about 1/5, and the MD
Rotation causes a difference of about 5 times between the data input amount and the output amount because of the same specified EFM speed as that of the CD. In order to compensate for such a difference, a memory 3 including a DRAM called a shock proof memory is provided as a data buffer.

The mutual operation (shock proof operation) of storing data in the memory 3, reading data from the memory 3, and activating the ATRAC decoder 4 is as shown in a time chart of FIG. Is stored in the memory 3 by appropriately controlling the ATRAC.S, and the process proceeds to the next step S2, where ATRAC · S
TOP? Is determined and if the ATRAC decoder 4 is not activated (stopped) and the result is No, the reading of the data by the reading head 2 and the storing of the data in the memory 3 are continuously performed, and Yes in step S2. Ie, A
If the TRAC decoder 4 has been activated, the process proceeds to the next step S3.

In step S3, it is determined whether or not the amount of data stored in the memory 3 is equal to or larger than a predetermined amount A. In the case of No, steps S1 and S2 continue. Executed, Yes, ie, memory 3
If the amount of data stored in the memory 3 is equal to or more than the predetermined amount A, the process proceeds to the next step S4, where the ATRAC decoder 4 is activated, and the stored data retrieved from the memory 3 is stored in the ATRAC.
The signal is input to the decoder 4 and ATRAC processing is performed.
An ATRAC decoder output signal 0UT is obtained at the output terminal of the RAC decoder 4, and is converted into a predetermined digital audio signal form or a predetermined analog audio signal form by a signal processing circuit (not shown) at the next stage.

Here, in the above-described shock proof operation, by adjusting the setting of the predetermined amount A, A
The activation timing of the TRAC decoder 4 can be adjusted. The smaller the predetermined amount A is, the shorter the time from the start of the reading operation (reproduction operation) by the reading head 2 to the time when the audio signal is actually obtained becomes shorter. ATRAC decoder 4 is activated while the data amount stored in 3 is small.

The MD recording section read by the reading head 2 may be formed of one continuous part or may read a plurality of parts in order. As a form of reading a plurality of parts in order, a series of readings is performed by jumping a track to an extremely close part (when the time required for a search movement is short), or the track order is changed (moving editing). In some cases, when a plurality of tracks are continuous (combine editing), a series of readings is performed by jumping tracks to relatively distant parts (the time required for search movement is long).

[0012]

A conventional activation controller for an ATRAC decoder in an MD player temporarily stores read data read by a read head in a memory, and the amount of data stored in the memory is set in advance. Since the stored data is taken out when the predetermined amount, which is a constant value, is reached and the signal processing for audio decompression is performed by the ATRAC decoder, depending on the setting of the above-mentioned predetermined amount, it may take until the final audio signal is obtained. It may take a long time.

When reproducing an MD on which move editing or combine editing has been performed, one program track (one song) is formed by a plurality of parts. Another problem is that a series of scans must be performed, and when the part to be read this time and the part to be read next are physically close to each other, the search moving time is short and it can be regarded as a substantially continuous part. However, if the part to be read this time and the part to be read next are located at physically separated locations, it will take a long time to obtain the final audio signal, and conversely, the audio signal will be obtained immediately. However, if the track length of the part to be read this time is extremely short and the part to be read next time is located at a physically separated part, There is a possibility that the sound interruption occurs.

Therefore, an object of the present invention is to provide a long time until a final audio signal is obtained due to the above-described setting of the predetermined amount, or a part where the current and next reading parts are physically separated from each other. It is an object of the present invention to provide an ATRAC decoder activation control device in an MD player that does not take a long time until a final audio signal is obtained or does not cause a sound interruption even if the audio signal is located.

[0015]

In order to solve the above-mentioned problems, an ATRAC decoder activation control device in an MD player according to the present invention employs the following characteristic configuration.

(1) A read head which reads a recording part consisting of one part recorded on the MD based on ATRAC audio compression data based on a read address sequence set and recorded in advance, and a read head which is read by the read head. A memory in which the read data is stored, an ATRAC decoder for expanding the stored data retrieved from the memory, and an ATRAC decoder when the amount of data stored in the memory reaches a predetermined value, The stored data is voice-expanded, the reading operation of the reading head to the recording unit is stopped, and when the amount of data stored in the memory becomes substantially empty, the reading head is activated to perform the recording. And a control unit for controlling read data read from the memory unit to be stored in the memory. A control unit is provided which controls the activation timing of the ATRAC decoder to be delayed when the part is short and to be set earlier when the part is long, in accordance with the length of the part of the recording unit being read by the part. .

(2) A read head for reading a recording part consisting of a plurality of parts recorded on the MD based on ATRAC audio compression data based on a preset read address sequence, and a read head read by the read head. A memory in which the read data is stored, an ATRAC decoder for voice-expanding the stored data taken out of the memory, and, when the amount of data stored in the memory reaches a predetermined value, activating the ATRAC decoder; The stored data is voice-expanded, the reading operation of the reading head from the recording unit is stopped, and when the amount of data stored in the memory becomes substantially empty, the reading head is activated to perform the recording. And a control unit for controlling read data read from the memory unit to be stored in the memory. A control unit that controls the activation timing of the ATRAC decoder to be set late when the overall length is long and to be set earlier when the overall length is short, in accordance with the overall length of the plurality of parts of the recording unit being read by the recording unit. Is provided.

(3) The control unit according to (2) is controlled by the ATR according to the time required for the search to move to each of a plurality of parts of the recording unit being read by the reading head.
The configuration is such that the activation timing of the AC decoder can be controlled so as to be set later when the required moving time is long and to be set earlier when the required moving time is short.

(4) The control unit of (2) sets the start timing of the ATRAC decoder to be slower when the entire length is long, corresponding to the total length of a plurality of parts of the recording unit being read by the read head. When the total length is short, the start timing of the ATRAC decoder is controlled in accordance with the time required for the search to move to each of the plurality of parts of the recording unit being read by the read head. Is set to be set later when the required moving time is long, and set earlier when the required moving time is short.

(5) The control unit according to (3) or (4) includes a current reading part detecting unit that detects an address of a part of a recording unit that is currently read by the reading head; A next reading part detecting unit for detecting an address of a part of the next recording unit that has been set, and calculating a moving time required for the reading head based on respective data of the present reading part detecting unit and the next reading part detecting unit. It is constituted so that.

(6) The controller of any one of (3) to (5) may be used to control the recording unit to be read next time even if the length of the part of the recording unit read this time by the reading head is short. If the parts are not physically separated, the ATRAC decoder is activated earlier.

[0022]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block circuit diagram showing a schematic configuration (a configuration emphasizing ATRAC processing) of an MD player to which the present invention is applied. Head 6, memory 7, ATRAC
The decoder 8, the current reading part detecting circuit 9, and the next reading part detecting circuit 10 are connected to perform a complex operation.

That is, the reading head 6 is an MD (not shown)
This is for reading signals with an optical pickup arranged opposite to the recording surface of the optical pickup. The focus error signal and the tracking error signal necessary for controlling the just focus and just tracking of the optical pickup, and the address information of the MD recording area. Servo, EFM (8-14 modulation) and ACIRC of a certain ADIP FM signal
(Code error correction).

A read signal read from the MD by the read head 6 under the control of the CPU 5 and subjected to EFM and ACIRC signal processing is temporarily stored in the memory 7 and then taken out and input to the ATRAC decoder 8. Is done.

The ATRAC decoder 8 compresses an audio signal and expands the recorded data to its original state. The audio compression at the time of recording is usually about 1/5.
Rotation causes a difference of about 5 times between the data input amount and the output amount because of the same specified EFM speed as that of the CD. In order to compensate for such a difference, a memory 7 composed of a DRAM called a shock proof memory is provided as a data buffer.

The current reading part detection circuit 9 receives TOC and UTOC information and address information recorded on the MD, decodes the information, generates time display data, and detects the current reading position of the reading head 6. It is configured to be.

The next reading part detection circuit 10 receives TOC and UTOC information and address information recorded on the MD, decodes the information, generates time display data, and detects the next reading position of the reading head 6. It is configured to be.

The start-up control circuit 11 controls the AT according to the length of the part of the recording section being read by the read head 6.
The control unit controls the activation timing of the RAC decoder 8 to be delayed when the part is short, and to be set earlier when the part is long, and a plurality of parts of the recording unit being read by the read head 6. The control unit controls the activation timing of the ATRAC decoder 8 to be set later when the overall length is long, and to be set earlier when the overall length is short, corresponding to the overall length of the ATRAC decoder 8.

The activation control circuit 11 controls the ATRAC decoder 8 in accordance with the time required for the search to move to each of the plurality of parts of the recording section being read by the reading head 6.
The control unit controls the start timing of the recording unit to be set to be late when the required moving time is long, and to be set early when the required moving time is short. The activation timing of the ATRAC decoder 8 is set according to the total length of the part.
When the total length is long, it is set to be slow, and when the total length is short, it is set to be early. In addition, it corresponds to the time required for the search to move to each of the plurality of parts of the recording unit being read by the reading head 6. ATRA
The configuration is such that the activation timing of the C decoder 8 is set to be late when the required moving time is long and to be set early when the required moving time is short.

The operation (shock proof operation) of the activation control device of the ATRAC decoder in the MD player configured as described above first controls the read head 6 appropriately in step S5 as shown in the time chart of FIG. Then, the read data is stored in the memory 7, and the process proceeds to the next step S6, where ATRAC STOP?
Is determined, and if the ATRAC decoder 8 is not activated (stopped) and the result is No, the read head 6
, And data storage in the memory 7 is continuously performed. In step S5, Yes, that is, ATRAC
If the decoder 8 has been activated, the next step S
Go to 7.

Incidentally, reference numerals A to G in the following operation description
Are as follows. The data storage amount A is a condition for activating the ATRAC decoder 8 after storing more data in the memory 7, and the data storage amount B is for activating the ATRAC decoder 8 when reproducing a general MD. Is the difference between “the current reading end address D of the part currently being read by the reading head 6” and “the current reading address E of the part currently being read”. Based on the time.

The fixed set value F is a time uniquely determined from the time required for the search and the like.
This is the amount of data stored in the memory 7 when the RAC decoder 8 is activated.

Step S7 in FIG. 2 is for calculating the search movement time C, and is based on the difference between the "current read end address D" and the "current read address E" obtained by the read part detection circuit 9. Is obtained, and in the next step S8, C <F? Is determined, in the case of Yes, the storage amount G = data storage amount B in step S9, and in the case of No, the storage amount G = data storage amount A in step S10.

Whether or not the data amount gradually stored in the memory 7 based on the setting of the data storage amount B or the data storage amount A executed in step S9 or S10 is equal to or more than a specified value (storage amount G). Is determined in step S11, and if No, step S5 to step S1
1 is repeatedly executed as described above.

If the answer is Yes in step S11, the ATRAC decoder 8 is activated by the activation control circuit 11 in the next step S12, and the data stored in the memory 7 is stored in the ATRAC decoder every predetermined block. The ATRAC decoder 8 performs an expansion process, and an ATRAC decoder output signal 0UT is obtained at the output end of the ATRAC decoder 8. The ATRAC decoder 8 outputs a predetermined digital audio signal form by a signal processing circuit (not shown) at the next stage. Or a predetermined analog audio signal form.

Therefore, when the number of remaining sectors of the part being reproduced by the read head 6 is small, it is expected that a search will be performed up to a physically distant track position in order to reproduce the next part. The ATRAC decoder 8 is activated after storing a sufficient amount of read data in the memory 7.

On the other hand, when the part being reproduced by the read head 6 is continuous for a while (this condition is almost the same in a normal MD), the ATRAC decoder 8 is activated early before the memory 7 becomes full. By doing so, the output timing of the finally obtained audio signal is advanced.

In the above examples, when reproducing a plurality of parts, the ATRA is simply set on condition of only the length of the parts.
Although the C decoder 8 is activated, as shown in the flowchart of FIG. 3, even if the length of the part of the recording unit that is read this time by the reading head 6 is short, the part of the recording unit that is read next time is physically stored. ATR as soon as you are not away
Control may be performed to activate the AC decoder 8.

That is, it is determined in step S13 whether or not the currently reproduced part is short. If the result is No, the flow advances to step S17 to activate the ATRAC decoder 8 at the shortest time before the memory 7 becomes full. Let it.

If Yes in step S13, the process proceeds to the next step S14, where it is determined whether the next part to be reproduced is physically separated or not. The address position data of the current read part and the address position data of the next read part obtained by the read part detection circuit 10 are compared to calculate the distance required for movement (search).

If step S13 is No,
That is, if the current and next reproduction parts are close to each other, the process proceeds to step S17, where the ATRAC decoder 8 is activated at the shortest time before the memory 7 becomes full, and the data stored in the memory 7 is stored in the ATRAC decoder every predetermined block. 8 and is subjected to decompression processing by the ATRAC decoder 8, and the ATRAC decoder 8
An ATRAC decoder output signal 0UT is obtained at the output terminal of the AC decoder 8, and is converted into a predetermined digital audio signal form or a predetermined analog audio signal form by a signal processing circuit (not shown) at the next stage.

On the other hand, in the case of Yes in step S14, the process proceeds to the next step S15, where A is determined by the distance (address information) between the current part reproduction and the next part reproduction.
The TRAC activation condition is determined, and the process proceeds to the next step S16, where the ATRAC decoder 8 is activated based on the address information.
Is started, the data stored in the memory 7 is output to the ATRAC decoder 8 for each predetermined block, the ATRAC decoder 8 performs the expansion processing, and the ATRAC decoder output signal 0UT is obtained at the output end of the ATRAC decoder 8. The signal is converted into a predetermined digital audio signal form or a predetermined analog audio signal form by a signal processing circuit (not shown).

[0043]

As is apparent from the above description, according to the activation control apparatus of the ATRAC decoder in the MD player according to the present invention, the read data read by the read head of the MD player is temporarily stored in the memory. When the amount of data stored in the memory reaches a predetermined amount that is a preset constant value, the ATRAC decoder is not uniquely activated, and the activation timing is controlled based on the length of the part currently being reproduced. Therefore, a long time is not required until a final audio signal is obtained, and the audio signal can be obtained in a minimum necessary time.

When playing back an MD on which move editing or combine editing has been performed, one program track (one song) is formed by a plurality of parts. Although a sound interruption may occur due to performing a series of readings, the present invention employs an AT depending on whether a part to be read this time and a part to be read next are physically close to each other or at a long distance.
Since the activation timing of the RAC decoder is controlled, no sound interruption occurs.

Therefore, according to the present invention, it takes a long time until the final audio signal is obtained due to the uniquely set storage data amount, or the current and next reading parts are physically Even if it is located in a distant part, it may take a long time to obtain the final audio signal,
ATR in MD player without interruption of sound
An activation control device for an AC decoder can be provided.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram showing a circuit configuration emphasizing ATRAC processing of an MD player to which the present invention is applied.

FIG. 2 is a flowchart illustrating an example of a start operation of an ATRAC decoder of the MD player shown in FIG. 1;

FIG. 3 is a flowchart for explaining another example of the activation operation of the ATRAC decoder of the MD player shown in FIG. 1;

FIG. 4 is a block circuit diagram showing a circuit configuration emphasizing ATRAC processing of a conventional MD player.

FIG. 5 is a flowchart illustrating an example of a start operation of an ATRAC decoder of the MD player shown in FIG. 4;

[Explanation of symbols]

 5 CPU 6 Reading head 7 Memory 8 ATRAC decoder 9 Current reading part detection circuit 10 Next reading part detection circuit 11 Startup control circuit

Claims (6)

[Claims] An MD based on ATRAC audio compression data.
A read head for reading a recording unit consisting of one part recorded on the basis of a read address sequence set in advance, a memory for storing read data read by the read head, An ATRAC decoder for expanding the stored data by voice, and when the amount of data stored in the memory reaches a predetermined value, the ATRAC decoder
Activating a RAC decoder, decompressing the stored data, stopping the reading operation of the reading head from the recording unit, and setting the read head when the amount of data stored in the memory becomes substantially empty. And a control unit for controlling to store read data obtained by reading the recording unit in the memory, the control unit corresponding to the length of the part of the recording unit being read by the reading head. A control unit for setting a start timing of the ATRAC decoder to be delayed when the part is short and to be set earlier when the part is long.
AC decoder activation control device. 2. An MD based on ATRAC audio compression data.
A reading unit that reads a recording unit composed of a plurality of parts recorded on the basis of a read address sequence set and recorded in advance, a memory that stores read data read by the read head, and a memory that is extracted from the memory. An ATRAC decoder for expanding the stored data by voice, and when the amount of data stored in the memory reaches a predetermined value, the ATRAC decoder
Activating a RAC decoder, decompressing the stored data, stopping the reading operation of the reading head from the recording unit, and setting the read head when the amount of data stored in the memory becomes substantially empty. And a control unit that controls to store read data obtained by reading the recording unit in the memory, the control unit corresponding to a total length of a plurality of parts of the recording unit being read by the reading head. And a control unit for setting the start timing of the ATRAC decoder to be late when the total length is long and to be set early when the total length is short. apparatus. 3. The control unit according to claim 1, further comprising: a start timing of the ATRAC decoder corresponding to a moving time required for a search to each of the plurality of parts of the recording unit being read by the reading head; 3. The activation control device for an ATRAC decoder in an MD player according to claim 2, wherein the control is performed such that the setting is made slower when the moving time is long and earlier when the moving time required is short. 4. The control unit sets the activation timing of the ATRAC decoder in accordance with the total length of a plurality of parts of the recording unit being read by the read head, when the full length is long, and sets the activation timing later. Is shorter, and the start timing of the ATRAC decoder is set in accordance with the required moving time of the search to each of the plurality of parts of the recording unit being read by the read head. 3. The activation control device for an ATRAC decoder in an MD player according to claim 2, wherein control can be performed such that the delay is set when the time is long and the movement is set early when the required moving time is short. 5. The current reading part detecting section for detecting an address of a part of a recording section currently read by the reading head, a control section for detecting a part of a next recording section currently read by the reading head. A next reading part detecting unit for detecting an address, and a time required for moving the reading head are calculated based on respective data of the present reading part detecting unit and the next reading part detecting unit. An activation control device for an ATRAC decoder in an MD player according to claim 3 or 4. 6. The control unit according to claim 1, wherein the part of the recording unit to be read next time by the reading head is short if the part of the recording unit to be read next is not physically separated. 6. The activation control device of an ATRAC decoder in an MD player according to claim 3, wherein the activation control device is configured to activate the decoder.