JPS63214984A - Music selecting system in disk reproducing device - Google Patents

Abstract

PURPOSE:To use a memory small in a storage capacity and to shorten a reproducing time by reading all the reproducing time and all the number of musics from a time code, calculating an average time peer one music from all the reproducing time and all the number of the musics at the time of selecting the music and searching the music number of the selected music based on the time. CONSTITUTION:At the time of reproducing a disk set in a disk reproducing device, all the reproducing time and all the number of the musics are read from the time code as accumulating totals recorded in a read in part to decide the music number of the selected music. The average time per one music is calculated from all the reproducing time and all the number of the musics and the music number of the music selected on this time is searched based on this time. Thereby, the memory small in the storage capacity can be used and the time to a reproduction can be shortened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a method for recording a cumulative time code (TOC) when an operator selects a specific song when playing a disc.
The present invention relates to a song selection method in a disc playback device, in which the selected song number is searched from the total playback time and the total number of songs read in advance.

[Conventional technology and its problems]

When an operator selects a specific song on an optical disc, such as a compact disc, a method is used to search from the address of the track number in the cumulative time code (hereinafter referred to as TOC) information read in advance in the lead-in section. was.

By the way, the TOC contains the total number of songs recorded on the disc, the playback time (hours and minutes) of the total number of songs, and the address and playback time of each song, so the amount of information is enormous. Storing all of this information in memory requires a considerable amount of memory, which increases costs, and it also takes a long time to read all of the information. There was a problem in that it took a long time to start playing.

[Purpose of the invention]

The present invention aims to solve the above-mentioned problems by reading only a small amount of information from the TOC information in the lead-in and making it possible to search for the selected song number.
It is an object of the present invention to provide a music selection method in a disc playback device that can utilize a memory with a small storage capacity and shorten the time until playback.

[Summary of the invention]

In order to achieve the above-mentioned object, the present invention provides T.

Only the total playback time and total number of songs are read from C, and when a song is selected, the average time per song is calculated from the total playback time and the total number of songs, and the selected song number is searched based on this time. This is what I decided to do.

[Embodiments of the invention]

Next, a case in which an embodiment of the present invention is applied to a disc playback device that selects and plays one disc from a magazine containing a large number of discs will be described with reference to FIG.

In FIG. 1, l is a magazine in which N (N is a natural number of 2 or more) disks are arranged and stored in order with a predetermined pinch. The magazine 1 is provided with N trays for carrying disks in a housing that protrudes from the magazine body. The magazine 1 is detachably attached to a predetermined attachment portion. One of the N disks D and -DH stored on the N trays each serving as a plurality of disk storage positions provided in the magazine 1 is transferred to the rotating shaft of the spindle motor 3 by the disk ejecting and conveying mechanism 2. It is conveyed and clamped onto the disk supporting surface of the turntable 4 to which it is fixed. The disc ejecting and transporting mechanism 2 includes a protruding member that protrudes the tray of the magazine 1 and moves the disc onto the disc supporting surface of the turntable 4, and a projecting member that causes the disc to move onto the disc supporting surface of the turntable 4 when the disc is moved onto the disc supporting surface of the turntable 4. It has a clamp mechanism that clamps the disk, a moving plate that changes the relative position of this protruding member with respect to the magazine 1 in the tray arrangement direction, and a sensor that detects the position of the moving plate, the operation of the clamp mechanism, etc. ing. This disk ejection transport mechanism 2
By moving the movable plate at , the position of the protruding member changes, making it possible to select a disc. The structures of the magazine 1 and the disk ejecting and transporting mechanism 2 are detailed in Japanese Patent Application No. 153651/1983.

Recorded information on the disk Dn, which is taken out from the magazine l by the disk ejecting and conveying mechanism 2 and clamped onto the disk holding surface of the turntable 4, is read by the optical pickup 6. The pickup 6 includes a laser diode, an objective lens, a focus actuator, a tracking actuator, a photodetector, and the like.

The output of the pickup 6 is supplied to each of a focus servo circuit 7, a tracking servo circuit 8, and a reproduction clock generation circuit 9 including an RF amplifier.

In the focus servo circuit 7, a focus error signal is generated by, for example, an astigmatism method, and a focus actuator in the pink-up 6 is driven in accordance with this error signal. As a result, the laser light emitted from the laser diode and passed through the objective lens is focused on the recording surface of the disk Dn, forming an information detection light spot. Further, in the tracking servo circuit 8, a tracking error signal is generated by, for example, a push-pull method, and this error signal is sent to the trunking actuator in the pickup 6 and the carriage servo circuit 10. The output of the carriage servo circuit 10 is supplied to a motor Ma that drives a carriage (not shown) carrying the pink-up 6, and the pickup 6 is sent in the radial direction of the disk Dn.

A reproduced clock signal for demodulation is generated in the reproduced clock generation circuit 9 and supplied to the spindle servo circuit 11. In the spindle servo circuit 11, a drive signal corresponding to the phase difference between the reproduced clock and the reference clock from the clock generation circuit 12 is generated to drive the spindle motor 3, and control the trunk linear velocity of the disk Dn to be constant. be done. Further, the output of the RF amplifier in the reproduced clock generation circuit 9 is supplied together with the reproduced clock to an EFM demodulation circuit 13 including a frame synchronization circuit. The demodulated output of the EFM demodulation circuit 13 is processed by a data processing circuit 14 that performs deinterleaving, error detection, correction, correction, etc. of the demodulated data signal.

Thereafter, the demodulated output is temporarily stored in a data memory 15, read out using a clock signal from a clock generation circuit 12, and converted into an analog signal by a D/A (digital/analog) converter 16. This analog signal is output as left and right audio signals via an LPF (low pass filter) 17 and an amplifier 18. Furthermore, amplifier 18
is configured to receive control data and change its frequency characteristics in accordance with the control data.

On the other hand, E F Mil! The control signal in the data from the circuit 13 is supplied to the system controller 20,
Various information such as during a song, between songs, song number, playing time, and disc model number can be read. The system controller 20 is formed of one or more microcomputers including a processor, ROM (read-only memory), RAM (random access memory), an interface circuit, a timer, and the like. In this system controller 20, a processor is a ROM
The carry 7 operates according to a program stored in advance in the computer and based on the flowchart shown in FIG. diservo circuit lO, spindle servo circuit 11, amplifier 18,
It supplies various commands and data to the display 22 and drive circuits 24 and 25. The random number generation circuit 23 is configured to, for example, latch and output the output of an m-ary (m is a natural number) counter whose coefficient values sequentially change in extremely short cycles in response to a data output command. Further, the drive circuit 24.
25 are motors M b and M that respectively drive the moving plate and the protruding member in the disk ejecting and transporting mechanism 2;
It is configured to supply a drive current to C according to a command.

Note that 26 is a RAM that stores information from the system controller 20.

81 to S4 are various detection switches arranged near the magazine 1 mounted in a predetermined mounting part, Sl is a magazine detection switch that sends out an output when the magazine 1 is mounted in a predetermined mounting part, S is a A disk detection switch that detects the presence or absence of a disk in the protruded tray; S3 is a tray detection switch that detects whether a tray is stored in the magazine 1; S4 is a position of the magazine 1 that moves up and down with respect to the turntable 4; This is a magazine position detection switch that detects the position of the magazine.

Next, the operation of the processor in the system controller 20 will be explained with reference to the flowchart of FIG.

First, when the power is turned on, the processor monitors whether or not the magazine 1 is inserted into the predetermined mounting section.Step a)
, when magazine 1 is installed in a predetermined mounting section and magazine detection switch Sl detects that magazine 1 is set and sends the detection signal to the processor, the processor
determines that is set and proceeds to the next step, and
If it is not attached, the operation will stop.

In the next step, the magazine 1 is moved up and down to set the magazine 1 to a position where the top or bottom tray can be pulled out (step b), and the magazine position detection switch S4 receives the position signal of the magazine 1. Once sent to the processor, the processor proceeds to the next step.

In the next step, it is detected whether or not there is a disc in the tray to be pulled out.In step C,), when the disc detection switch S detects a disc, it advances to the next step, and in the next step, the playback switch is turned on. In step d), if the processor does not detect that the playback switch is turned on, it waits for the playback switch to be operated, and if the playback switch is operated and turns on, the processor starts loading the disc. outputs a signal to the playback device.

Therefore, the playback device loads the disc (step e), rotates the disc, and jumps the pickup to the lead-in portion of the disc (step f).

At this time, the processor monitors whether the pickup has been lead-in or not (step g), and if the pickup has not been lead-in, returns to the previous step f, and if lead-in is confirmed, proceeds to the next step.

In the next step, the TOC is read (step h), and the processor monitors whether the result of reading the TOC is point AO (step i). This information represents a number, and monitors whether this information has been read. If the read result is point 'AO, then necessary information of TOK is read (step n).

That is, following the total number of songs, only the playback times (hours and minutes) of all the songs are read and recorded in the memory.

-・In reading the above TOK, point AO
If not, the processor calculates the frame position of the point AO of the next TOK from the read information (step j), then makes the pickup jump the track (step k), and returns to the trunk position. Read the TOK at the jump position (
Step Il). Then, it is monitored whether the read TOK information is the point AO or not (step m). If the point AO is read, the process proceeds to the step n, and if the point AO is not read, the frame calculation step j is performed. Go back to the previous point and repeat the above operation again. By performing the above operations, only the total playback time and the total number of songs are stored in the memory.

After reading only the necessary information in this way, a search is performed for the first song (step o), and once the search is completed, playback is started (step p). Then, the processor monitors whether or not a song is selected during this playback, and also monitors which song number is selected (step q).
). Here, when a specific song number is selected, this song number is memorized and the process proceeds to the next step. Then, the processor performs calculation A by dividing the memorized total playback time by the total number of songs (
step r). From this calculation result A, the processor calculates A
Calculation B of X (selected song number - currently played song number) is performed (step s), and the processor starts searching for the calculation result B (step t).

In this search, the processor monitors whether it is the selected song number or not (step u), and when the selected song number is detected, the processor starts playback from that position and ends the operation.

Note that the above explanation deals with the case where the song selection operation is performed during playback, but if the song selection operation is performed before playback, the search for the selected song number can be performed directly without starting playback of the first song. It is natural to start.

〔Effect of the invention〕

As described above, the present invention reads only the total playback time and the total number of songs from the TOC, and when a song is selected, calculates the average time per song from the total playback time and the total number of songs, and calculates the average time per song based on this time. Since the selected song number is searched, it is possible to use a memory with a small storage capacity, and therefore, it is possible to manufacture products at a low price. Since the address recorded for each song on the disc can be read without having to read the address recorded for each song on the disc, the playback time can be shortened.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of a disc playback device used in the present invention, and FIG. 2 is a flowchart according to the present invention. ■...Magazine, 2...Disc ejection transport mechanism, 2
0...System controller, SI...Magazine detection switch, S2...Disk detection switch, S3...
...Tray storage detection switch, S4...Magazine position detection switch.

Claims (1)

[Claims] When playing a disc set in a disc playback device, the total playback time and total number of songs were read from the cumulative time code (TOC) recorded in the lead-in section, and the number of selected songs was determined. A music selection method for a disc playback device, characterized in that the average time per song is calculated from the total playback time and the total number of songs, and the selected song number is searched based on this time.