JPH0519916Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field to which the invention pertains The present invention relates to a playback device for optical discs, etc., and in particular to a disc playback device that can reproduce signals from the optical disc by continuously connecting randomly selected positions. Regarding equipment.

Prior art and its problems Various optical disk devices that can record and play back data at high density using optical heads have become available, and audio and video can be recorded and played back using digital signals on the optical disks used in these devices. Compared to a case tape device, it has the advantage of being able to pick up the cue at high speed when randomly extracting signals from different locations and making them into one continuous signal. However, when recording music and other information and editing and unifying the information, it takes about 1 second even if you quickly move the head to another location at the editing point. For example, while the optical pick-up is searching for the next address, the slave is stopped and recorded as a continuous signal, and the information created by the slave is played back from the disk or tape, etc. It was complicated because it needed to be a continuous source of information.

Purpose of the invention The present invention has been made in view of the above-mentioned drawbacks, and it is an object of the present invention to provide a disk playback device that can obtain a unified information signal without requiring a slave.

Structure of the invention According to the invention, a buffer memory is created, data is inputted into this buffer memory sequentially, and if an edit point is being searched, for example, for one second, data is not written to the buffer memory during this time, but the data after the search is continuously written. Eggplant. Data is read from the memory at a constant clock rate and taken out as one continuous piece of data. If there is an edit point here, the input data is small and the output is kept constant, so the data decreases. Therefore, by detecting a decrease in the amount of data stored in the memory, the data read from the disk and stored in the memory is accelerated.In other words, the rotation of the disk is accelerated so that a constant amount of data stored in the memory is always maintained. The above purpose can be achieved by controlling the temperature so as to maintain it.

Embodiment of the invention Hereinafter, an embodiment of the invention will be described in detail with reference to the drawings. Figure 1 shows the system diagram of the present invention.
FIG. 2 is a waveform explanatory diagram of FIG. 1.

In FIG. 1, reference numeral 1 has an optical disk or the like, and the information in the optical disk can be accessed at random, and data d ₁ and clock signal CK ₁ can be extracted from these information signals. Various such disc reproducing devices have been proposed and are well known, so the details thereof will be omitted.Furthermore, the disc rotation servo normally performs phase comparison servo using an internal oscillator or the like as a reference. There are, but
In the present invention, the reference voltage is varied by the control voltage V, and the control voltage V applied to the disc playback section is varied to servo the disc drive motor to speed up or slow down its rotation speed. .

In the disk playback unit 1, a predetermined position on the disk is randomly accessed and played back, and data d ₁ is played back.
Take it out and add it to memory 2, and then add it to clock CK ₁ .
is taken out and used as the write clock of the write address section 4. Reference numeral 3 denotes a read address section which is controlled by a constant frequency from an oscillator 5 such as a crystal and reads out data stored in the memory 2 at a constant speed.
This read output _d2 is output as an analog signal through the digital-to-analog conversion circuit 10 (hereinafter referred to as DAC). Here, the clock _CK1 to the write address section 4, which generates the address for writing data _d1 to the memory 2, is activated as shown in Figure 2B while the optical pickup, etc. is searching for the next data on the disk. However, since the read clock CK ₂ applied to the read address section 3 is a continuous clock as shown in FIG. 2A, the data in the memory 2 is continuously read in the read address section. The address counter outputs AC ₁ and AC ₂ of the read address 3 and write address 4 are added to the first comparator 6 and compared, and a comparison output C ₁ is output. This comparison output is used for constant reproduction. The inside is always circulated with a fixed amount of address difference.

As shown in FIG. 2C, when the optical pick-up stops reading data due to a search or the like and the clock _CK1 is interrupted like L, the read address value approaches the write address value and the comparator 6 detects this difference. The output C ₁ decreases. This comparator 6
The output C ₁ is added to the second converter 7 and subtracted by the reference data section 8 which outputs constant reference data r. The value of r is usually 1/1 of the memory capacity.
It is possible to use the number of data of 2. This means that during steady playback, the write address and read address are sequentially rotated through half of the memory. The output of the second comparator 7 is
In addition to the DAC 9, the rotation control voltage V is applied to the disc playback unit 1 as shown in FIG. Now, while the optical pickup is searching for the next data as shown at L in Figure 2B, the output _C1 of the comparator 6 becomes smaller as shown in Figure 2C, and the output of the second comparator 7 changes. The data of C ₂ becomes larger, and when the output C ₂ is converted into an analog signal by the second DAC 9, the voltage V increases as shown in FIG. 2D, speeding up the rotation. When clock CK ₁ is input, since the drive motor rotates quickly at this time, data d ₁ and clock CK ₁ are both faster than read clock CK ₂ , and the value of write clock CK ₂ gradually increases until the predetermined value is reached. As the difference approaches, the control voltage V also approaches zero and returns to its original state. Here, the above comparator 6
is constructed as shown in FIG. That is, address counter outputs AC ₁ and AC ₂ of read and write addresses 3 and 4 are applied to the comparator 6a.
Normally, the values of AC ₁ and AC ₂ are positive in the output of the converter 6a because the counter repeats from 0 to a predetermined value. If it is, it is output as is, and if it is negative, the maximum number D of the counter is added. Therefore adder 6
This state is shown in FIG. 4, in which the output obtained by adding the maximum number to b and the output without adding the maximum number from the data generating section 6c having the maximum number D, and the output not added are given to the gate circuit 6d and selected by the polarity bit signal SIN. i.e. count output
When AC ₁ AC ₂ is negative, as shown in Figure 4A, the count output AC ₁ AC ₂ is added to the maximum count number D as shown in Figure 4B, so that the predetermined data is output from the gate circuit 6d. can be obtained.

In the above embodiment, a case was explained in which information from different locations is made to be continuous.However, by leaving a certain interval at the connection point, for example, by inserting a clock for a certain period of time when switching with no-signal data, a managed space can be created. Naturally, it is also possible to crossfade the data of the connected locations using a calculator or the like.

Effects of the invention Since the invention was constructed as described above, music was recorded on-site in order to search different locations on the disk and output the output without any omissions even if there were omissions in the reproduced signal. Very useful for later editing.

[Brief explanation of drawings]

Figure 1 is a system diagram of the disc playback device of the present invention.
Figures 2 A to D are waveform explanatory diagrams of Figure 1, Figure 3 is a system diagram of the first comparator in Figure 1, Figure 4 A,
B is a waveform explanatory diagram of FIG. 3. 1...Disk playback section, 2...Memory, 3...
Read address section, 4... Write address section, 5... Oscillation circuit, 6... First comparator, 7... Second comparator, 8... Reference data section, 10, 9... First and first 2 of
D.A.C.

Claims (1)

[Scope of utility model registration request] When playing back signal information recorded on a disk,
means for discontinuously retrieving and reproducing signal information from different locations on a disk; a memory for temporarily storing the reproduced data; a means for reading and outputting data from said memory at a constant speed; A disk playback device comprising means for detecting the amount of data retrieved and controlling the rotation of the disk so that the amount of stored data is approximately constant, and continuously playing back the retrieved data. .