JPH09167444A - Optical disk reproducing method and device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the method and the device for an optical disk reproduction in which the rotational speed of the disk is constantly maintained while plural programs are continuously reproduced. SOLUTION: An optical disk 201, to which a recording is made with a rotational speed N, is rotated with a rotational speed M (>N) and the reproduced data are written into a memory circuit 209 through a data input control circuit 208. A data processing circuit 211 reads the reproduced data from the circuit 209 at the speed equivalent to the speed N. During this operation, the storing amount of the data and the amount of the reference are compared at every one revolution unit. If the storing amount of the data is less than the amount of the reference, the data on the optical disk are reproduced again and the data are written in the circuit 209. Should the storing amount of the data be larger than the amount of the reference, the reproducing operation in which the reproducing data equivalent to N/(M-N)×J rotations are written during M/(M-N)×J rotations and the intermittent reproducing, in which the still operation equivalent to J rotations is conducted, are repeated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data reproducing method and a data reproducing apparatus for an optical disk, and more particularly, an optical disk for continuously reproducing a plurality of programs recorded in different areas on the optical disk without interruption between the programs. The present invention relates to a reproducing method and an optical disk reproducing device.

[0002]

2. Description of the Related Art When continuously reproducing a plurality of video and audio programs recorded in different areas on an optical disk,
The address of the next program is searched between programs. During such a search operation, the output video and audio may be temporarily stopped or in a mute state.
Therefore, there has been proposed a method of continuously outputting video and audio without interruption even during program search, that is, a method of seamless reproduction. It plays data faster than it was recorded from the optical disc,
This can be realized by once accumulating it in the memory and reading the reproduction data from the memory at the recording speed of the optical disk.

On the other hand, during reproduction of an optical disk, tracking may be lost or a reproduction signal may be interrupted due to vibration or the like. In this case, even if the reproduction signal from the optical disk is interrupted, it is preferable to output the video and audio without interruption. As a measure against this, the same method as the above seamless reproduction may be used. However, in this case, it is generally necessary to monitor the tracking state.

When data is reproduced from the optical disk at a speed higher than the normal speed and written in the memory based on such a method, the data is read from the memory at the normal speed. Therefore, overflow easily occurs in the memory.
In order to avoid this, if the amount of data stored in the memory is less than the predetermined reference amount, the disc is played at high speed,
If the standard amount is exceeded, there is a method of reproducing at the normal speed. As another method, there is a method in which the rotation speed of the disk is kept high and writing to the memory is temporarily stopped when the remaining amount of the memory falls below a certain value.

[0005]

However, in the conventional method as described above, that is, the method of changing the rotation speed of the optical disk depending on whether the amount of data in the memory exceeds the reference amount, the rotation speed is changed. Means needed,
Controlling the motor becomes complicated. Further, when the remaining amount of the memory becomes a certain value or less, the method of temporarily stopping the writing to the memory has a problem that the amount of data in the memory must be frequently checked.

The present invention has been made in view of the above-mentioned conventional problems, in which the rotation speed of the optical disk remains constant and the number of inspections of the amount of data stored in the memory is minimized. It is an object of the present invention to realize an optical disc reproducing method and an optical disc reproducing apparatus that enable seamless reproduction of audio and audio.

[0007]

In order to solve the above-mentioned problems, the invention according to claim 1 of the present application is to record data by rotating an optical disc on which data is recorded at a rotation speed N at a rotation speed M (> N). An optical disk reproducing method for reproducing the reproduced data, writing the reproduced data in a memory, and reading the reproduced data from the memory at a speed corresponding to a rotation speed N.
With the amount of data read from the memory at a speed corresponding to the rotation speed N within the maximum search time of the optical disc as a reference amount, the amount of data accumulated in the memory in I rotation units (I is an integer) after the reproduction of the optical disc is started. If the data storage amount is equal to or less than the reference amount, the data for I rotations is reproduced from the optical disk again to write the data in the memory, and the data storage amount is equal to the reference amount. If the amount is exceeded, the reproduction data of the optical disc is stored in the memory during rotation during M / (MN) × J (J is an integer and M / (MN) × J is an integer) rotation. Is repeated for N / (M−N) × J rotations, and intermittent reproduction for performing J rotations for writing no reproduction data in the memory is repeated.

According to the second aspect of the present invention, an optical disc on which data is recorded at a rotation speed N is rotated at a rotation speed M (>).
N), a motor for rotating the motor, a motor control circuit for controlling the rotation speed of the motor, an optical head for reproducing data recorded on the optical disk, an access control circuit for controlling the position of the optical head, and the optical head. A signal processing circuit that demodulates the signal, a memory circuit that temporarily holds the reproduction data processed by the signal processing circuit, and a data input control circuit that controls writing of the reproduction data to the memory circuit and stop of writing. A memory control circuit for managing the amount of data stored in the memory circuit, and reading data from the memory circuit at a speed corresponding to the rotation speed N,
A data processing circuit for converting into a video signal or an audio signal, and a system control circuit for controlling the access control circuit, the motor control circuit, the data input control circuit, and the memory control circuit, respectively, to seamlessly reproduce the data of the optical disc. And a system control circuit, wherein the system control circuit uses the amount of data read from the memory circuit at a speed corresponding to a rotation speed N within a maximum search time of the optical disk as a reference amount to reproduce the optical disk. After the start, the amount of data stored in the memory circuit is compared with the reference amount in units of I rotations (I is an integer). Is instructed to write data to the memory circuit and the data storage amount exceeds the reference amount, / (M-N) × J (J is an integer, and M / (M-N) × J is an integer value) during rotation, N /
The data input control circuit writes data to the memory circuit while the reproduction operation for (M−N) × J rotations and the intermittent operation for performing the still operation for J rotations are repeated and the still operation is performed. It is characterized by instructing not to do so.

With such a method and configuration, after the reproduction of the optical disk is started, the data storage amount of the memory circuit is compared with the reference amount in units of I rotations. The data for I rotations is reproduced and the data is written in the memory circuit. If the data storage amount exceeds the reference amount, during M / (M−N) × J rotations, N / (M−N) × J rotations of reproduction operation and J rotations of still operation are performed. Repeat intermittent playback. The data input control circuit does not write data to the memory circuit during the still operation. Here, since the reference amount is set based on the maximum search time of the optical disk device, it is possible to output video and audio without interruption, no matter how far apart a plurality of programs are on the optical disk.

According to the invention of claim 5 of the present application, an optical disc on which data is recorded at a rotational speed N is rotated at a rotational speed M (>).
The method is an optical disc reproduction method of rotating the recording data by rotating the recording data on the optical disc by rotating the recording data by rotating the recording data by rotating the recording data at a speed corresponding to a rotation speed N from the memory. The search time from the end of reproduction of the pre-reproduction program to the start of reproduction of the post-reproduction program is obtained from the final address of the pre-reproduction program to be reproduced first and the start address of the post-reproduction program to be reproduced next to the pre-reproduction program, The amount of data read from the memory at a speed corresponding to the rotation speed N within the search time is used as a reference amount, and after the reproduction of the optical disc is started, the amount of data stored in the memory and the reference amount in I rotation units (I is an integer). The amounts are compared, and if the data storage amount is equal to or less than the reference amount, the data for I rotations is reproduced from the optical disk again. Performing a write said reproduction data to said memory, if the data storage amount exceeds the said reference amount, M / (M-N) × J (J is an integer, and M / (M
-N) × J is an integer value) During the rotation, N / (M−N) × J rotations of the reproduction data for writing the reproduction data and J rotations for which the reproduction data is not written to the memory are performed. It is characterized in that the intermittent reproduction for performing the still operation is repeated.

Further, according to the invention of claim 6 of the present application, an optical disc on which data is recorded at a rotational speed N is rotated at a rotational speed M (>).
N), a motor for rotating the motor, a motor control circuit for controlling the rotation speed of the motor, an optical head for reproducing data recorded on the optical disk, an access control circuit for controlling the position of the optical head, and the optical head. A signal processing circuit that demodulates the signal, a memory circuit that temporarily holds the reproduction data processed by the signal processing circuit, and a data input control circuit that controls writing of the reproduction data to the memory circuit and stop of writing. A memory control circuit for managing the amount of data stored in the memory circuit, and reading data from the memory circuit at a speed corresponding to the rotation speed N,
A data processing circuit for converting into a video signal or an audio signal, and a system control circuit for controlling the access control circuit, the motor control circuit, the data input control circuit, and the memory control circuit, respectively, to seamlessly reproduce the data of the optical disc. An optical disc reproducing apparatus comprising :, the system control circuit starting from a last address of a first reproducing program recorded first on the optical disc and a first address of a second reproducing program reproduced next to the first reproducing program. , A search time from the end of the reproduction of the pre-reproduction program to the start of the reproduction of the post-reproduction program is determined, and the amount of data read from the memory circuit at a speed corresponding to the rotation speed N within the search time is used as a reference amount, and the optical disc Amount of data accumulated in the memory circuit in I rotation units (I is an integer) If the reference amount is compared, and if the data storage amount is less than or equal to the reference amount, data for I rotations is reproduced from the optical disk again to write data to the memory circuit, and the data storage amount is the reference amount. If it exceeds M / (M−N) × J (J is an integer and M /
(M−N) × J is an integer) During rotation, N / (M−
N) × J rotations of reproduction operation and J rotations of still operation are repeated, and control is performed so that data is not written to the memory circuit during the still operation. To do.

With such a method and configuration, the search time is obtained from the final address of the pre-reproduction program and the start address of the post-reproduction program recorded on the optical disk, and the reference amount is set based on this. After the reproduction of the optical disk is started, the data storage amount of the memory circuit is compared with the reference amount in I rotation units. If the data storage amount is equal to or less than the reference amount, the data for I rotations is reproduced from the optical disc again and the memory circuit is restarted. Write data to. If the data storage amount exceeds the reference amount, N / (M−N) × J
-N) The reproduction operation for J rotations and the intermittent reproduction for performing the still operation for J rotations are repeated. Then, during the still operation, control is performed so that data is not written in the memory circuit. In this way, the video and audio can be output without interruption between programs, and the capacity of the memory circuit can be reduced.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) An optical disk reproducing method and an optical disk reproducing apparatus according to a first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the schematic arrangement of the optical disc reproducing apparatus according to this embodiment. FIG. 2 is a schematic diagram of an optical disc. As shown in FIG. 1, the optical disc reproducing apparatus includes an optical disc 201 and a motor 20.
2. Optical head 203, access control circuit 204, motor control circuit 205, signal processing circuit 206, system control circuit 207, data input control circuit 208, memory circuit 20
9, a memory control circuit 210, and a data processing circuit 211.

Now, on the optical disc 201, for example, one frame of video data for one track is C at 1800 rpm.
It is assumed that it is recorded by the AV system. As shown in FIG. 2, three video programs A, B, and C are respectively recorded in different areas on the optical disc 201. In the optical disc reproducing apparatus of this embodiment, the program A and the program B are continuously reproduced. It shall be. Further, the number of rotations of the optical disc 201 during reproduction is set to 2200 rpm.

The access control circuit 204 is an optical head 203.
Is a circuit for performing the positioning and tracking control of, and is controlled by the system control circuit 207. The motor control circuit 205 controls the rotation speed of the motor 202.
During recording, the optical disc 201 is moved at the normal speed (1800 rp
Rotate at m) and play at normal speed or high speed (220
(0 rpm). The signal processing circuit 206 demodulates the signal from the optical head 203 and outputs video data and audio data.

The data input control circuit 208 is a circuit that controls whether or not to write data in the memory circuit 209 so that the amount of data stored in the memory circuit 209 becomes less than a predetermined value, and is controlled by the system control circuit 207. . The memory control circuit 210 is a circuit that monitors the amount of data stored in the memory circuit 209 based on the amount of written data and the amount of read data.
7 provides that information. The data processing circuit 211 is a circuit that performs data processing such as error correction and expansion on the video data or audio data read from the memory circuit 209 and outputs a video signal or audio signal to the outside.

The operation of the optical disk reproducing apparatus thus configured will be described. FIG. 3 is a flowchart showing a method of reproducing an optical disc. Before starting playback, first see Figure 2.
The start addresses and end addresses of the programs A and B are set in the system control circuit 207. According to this setting, the system control circuit 207 reproduces the program A from the optical disc 201, then jumps to the start address of the program B and generates a control program so as to reproduce the program B. Further, the system control circuit 207 obtains a reference amount for the data storage amount recorded in the memory circuit 209. This reference amount is defined as the data processing circuit 2 within the maximum search time (maximum seek time) of the optical disc 201.
11 corresponds to the amount of data that can be continuously read from the memory circuit 209. For example, the data processing circuit 211
If the data reading speed from the memory circuit 209 is 10 Mbit / sec and the maximum search time of the optical disc 201 is 0.5 sec, the reference amount is 5 Mbits or more.

In the flowchart of FIG. 3, at the start of reproduction in step S0, the system control circuit 207 sends a command to the motor control circuit 205 to rotate the motor 202 at 2200 rpm. Then, the system control circuit 207 sends a command to the access control circuit 204 so as to search for the start address of the program A. The access control circuit 204 moves the optical head 203 to the head of the program A. When the head address of the program A is found, the optical head 203 reproduces the data of the program A from the optical disc 201.

In step S1, the reference amount for the data storage amount of the memory circuit 209 is obtained from the maximum search time of the optical disc reproducing apparatus as described above. After the reproduction is started in step S2, the data for one rotation is first reproduced. The signal processing circuit 206 demodulates the signal reproduced from the optical head 203. Then, the data is written in the memory circuit 209 through the data input control circuit 208. The data input control circuit 208 controls whether to write the data output from the signal processing circuit 206 to the memory circuit 209. The memory control circuit 210 monitors the amount of data stored in the memory circuit 209 based on the amount of data written to and read from the memory circuit 209.

The data written in the memory circuit 209 is
Simultaneously with the writing, the data is read at a speed corresponding to 1800 rpm and given to the data processing circuit 211. Then, error correction and expansion processing are performed here, and the video signal is output to the outside. When the reproduction of the data for the first one rotation from the optical disc 201 is completed, the process proceeds to step S3, and the memory control circuit 210 compares the data storage amount of the memory circuit 209 with the reference amount. If the amount of data stored in the memory circuit 209 is less than or equal to the reference amount, the process returns to step S2, and the data for one rotation is reproduced from the optical disc 201 again.

When the amount of data accumulated in the memory circuit 209 exceeds the reference amount by repeating the above-mentioned operation, the system control circuit 207 thereafter performs the intermittent reproduction as shown in the operation after step S3. To control. FIG. 4 shows two programs A from the optical disc 201,
It is explanatory drawing which showed the time change of the data storage amount at the time of carrying out continuous reproduction (seamless reproduction) of B.

In the present embodiment, the data recorded at 1800 rpm is reproduced at 2200 rpm, and the memory circuit 20
From No. 9, data is read at a speed corresponding to 1800 rpm. Therefore, the optical disc 201 rotates 11 times within the time when the video of 9 frames is output.
Therefore, within the time when the optical disc 201 rotates 11 times,
Data for one frame, that is, for nine rotations, is recorded on the optical disc 201.
When reproduced from, the amount of data written in the memory circuit 209 and the amount of read data become equal. That is, 1
The amount of data stored in the memory circuit 209 before and after the operation of one rotation has the same value. As can be seen from the time axis of FIG. 4, the reproduction operation for 9 rotations and the still operation for 2 rotations are performed within the time when the optical disk 201 makes 11 rotations. When the still operation is performed, writing to the memory circuit 209 may be prohibited by the data input control circuit 208.

In the following, such an intermittent reproduction operation will be described using the procedure from step S4. Further, in order to make the description easier to understand, in the following description, during the operation of 11 rotations, the reproduction operation of 9 rotations is performed first, and then the still operation of 2 rotations is performed.

First, the system control circuit 207 initializes the counter in step S4 (counter = 1). Then, in the next step S5, the count value is checked. Here, for example, N = 1800, M = 2200, and the number of still times is J =
Since 2 is set, the value on the right side of the conditional expression in step S5 is 9. Since the value of the current counter is 1, the conditional expression of step S5 is satisfied, and the process proceeds to step S6 to perform the reproduction operation for one rotation. The data reproduced here is written in the memory circuit 209 through the signal processing circuit 206 and the data input control circuit 208. In step S8,
If the last track of the current program A has not been reproduced yet, it is determined that the data of the program A still remains, and the process proceeds to step S9.

Since the current counter value is 1 and the value on the right side of the conditional expression at step S9 is 11, the condition here is not satisfied, and the routine proceeds to step S10, where the counter value is incremented by 1. Let As a result, the value of the counter becomes 2. After that, the process returns to step S5 and the same operation is repeated. Meanwhile, the data reproduced from the optical disc 201 is transferred to the memory circuit 20 via the data input control circuit 208.
Write 9 Further, the data processing circuit 211 has 180
Data is read from the memory circuit 209 at a speed corresponding to 0 rpm, error correction and expansion are performed, and a video signal is output.

When the reproducing operation for one rotation is completed and the process proceeds to step S5 at the tenth rotation, that is, when the counter value is 10, the conditional expression of this step is not satisfied. Therefore, the process branches to step S7 and the still operation for one rotation is performed. This still operation can be realized by performing a reverse jump for one track and then performing a scan for one rotation.

When performing the still operation, the system control circuit 207 sends an instruction to the data input control circuit 208 so as not to write data in the memory circuit 209. However, the data processing circuit 211 continues to read data from the memory circuit 209 and continuously outputs a video signal. When such a still operation is performed twice, the value of the counter becomes 11. Therefore, the conditional expression of step S9 is satisfied, and the process returns to step S4. Then, similarly to the first intermittent reproduction, a reproduction operation for 9 rotations and a still operation for 2 rotations subsequent thereto are performed. When the final track of the program A is reached during the reproduction operation of 9 rotations in such intermittent reproduction of a plurality of times, the condition of step S8 is satisfied.

After the reproduction of the program A is completed, step S
When the process proceeds to 11, the start address of the next program B is searched. This is performed by the system control circuit 207 sending a new command to the access control circuit 204. While the data is reproduced from the optical head 201 during the program search, the data processing circuit 211 causes the memory circuit 20 to
The data reading from 9 is continued, and the video signal is output.

When the start address of the program B is found, it is determined in step S12 whether the data storage amount of the memory circuit 209 exceeds the reference amount. Memory circuit 20
In FIG. 9, the data processing circuit 211 stores more data than the data amount read from the memory circuit 209 within the maximum search time of the optical disc 201. Therefore, the data in the memory circuit 209 will not be lost when the search is completed. .
In this way, the memory control circuit 210 compares the accumulated amount of data with the reference amount.

As indicated by a point P in FIG. 4, when the data accumulation amount exceeds the reference amount at the time when the intermittent reproduction of the program A is completed, if the next one-revolution reproduction is performed as it is,
As shown by a broken line B2, the data storage amount is the memory circuit 209.
May exceed the capacity of. Therefore, when the data storage amount exceeds the reference amount, the process proceeds to step S13 to perform one rotation still. In this way, the still operation is repeated until the amount becomes equal to or less than the reference amount. Then, in step S12, when the data storage amount becomes equal to or less than the reference amount as indicated by point Q in FIG. 4, the process returns to the original step S2 and the solid line B1 in FIG.
Play continuously as shown in. .

In order to perform the operations after step S2 again,
The reproduction operation is continued for each rotation until the data storage amount of the memory circuit 209 exceeds the reference amount, and when the reference amount is exceeded, the intermittent reproduction is performed again.

When a plurality of programs recorded in different areas on the optical disc 201 are continuously reproduced by using the above-mentioned optical disc reproducing method by the optical disc reproducing apparatus, the programs can be reproduced without interruption between the programs. Can be output. In this case, the number of rotations of the optical disk can be kept constant regardless of the amount of data stored in the memory circuit 209. Furthermore, it is not necessary to compare the amount of data stored in the memory circuit with a predetermined reference amount during the intermittent reproduction.

In steps S2 and S6 of FIG. 3, the data storage amount is managed for each rotation of the optical disk in order to input the data from the optical disk. I rotation (I is an integer)
It may be managed for each.

(Embodiment 2) Next, an optical disk reproducing method according to a second embodiment of the present invention will be described. The optical disc reproducing apparatus for realizing the optical disc reproducing method of the present embodiment is the same as that shown in FIG. FIG. 5 is a flowchart showing the method of reproducing the optical disc of the present embodiment. This flowchart is characterized in that the process of step S1 of the flowchart shown in FIG. 3 is replaced with step SX, and the process of step SY is added between steps S11 and S12. Since the other parts are the same as those in the flowchart of FIG. 3, the description thereof will be simplified.

As in the case of the first embodiment, it is assumed that one frame of video data is recorded in one track on the optical disc 201 by the CAV method of 1800 rpm. Then, as shown in FIG. 2, three video programs A, B, and C are recorded in different areas on the optical disc 201, and here, the programs A, B, and C are successively reproduced in this order. Also, the optical disc 20 during reproduction
The rotation speed of 1 is 2200 rpm.

Before starting playback, first, program A, B, C
The start address and the end address of are set in the system control circuit 207, respectively. According to this setting, the system control circuit 207 reproduces the program A from the optical disc 201, then jumps to the start address of the program B to reproduce the program B, reproduces the program B, and then jumps to the start address of the program C. , And controls to reproduce the program C. At the start of playback,
In step SX, the search time from the end of the reproduction of the program A to the start of the reproduction of the program B is estimated, and the reference amount for comparison with the data storage amount of the memory circuit 209 is calculated from the estimated value.

For example, the speed at which the data processing circuit 211 reads data from the memory circuit 209 is 10 Mbit / sec, and the program A to the program B are read from the final address.
Assuming that the search time up to the first address of 0.2 is estimated to be 0.2 seconds, the reference amount becomes a value of 2 M bits or more. After that, the operation until the start address of the program B is searched is the same as in the case of the first embodiment. However, as described above, the reference amount for the amount of data stored in the memory circuit 209 is different from that in the first embodiment.

When the reproduction of the last track of the program A is completed during the reproduction operation in the intermittent reproduction, the start address of the program B is searched in step S11 as in the first embodiment. When the start address of the program B is found, the process proceeds to step SY, the search time from the final address of the program B to the start address of the program C is estimated, and the value is used as a reference amount for comparison with the data storage amount of the memory circuit 209. Make a calculation. Then, the reference amount set in step SX is updated. If the search time from the last address of program B to the first address of program C is estimated to be 0.05 seconds, the reference amount here is a value of 0.5 M bits or more.

Then, in step S12, the data storage amount of the memory circuit 209 is compared with the newly obtained reference amount. The memory circuit 209 stores more data than the data amount read from the memory circuit 209 by the data processing circuit 211 within the search time from the final address of the program A to the start address of the program B on the optical disc 201. Therefore, when the search is completed, the memory circuit 20
The accumulated data of 9 never disappears.

As a result of the comparison in step S12, if the amount exceeds the reference amount, the process proceeds to step S13, and the still operation is repeated until the amount becomes less than the reference amount. If the data storage amount becomes equal to or less than the reference amount in step S12, the process returns to the original step S2, and the reproduction operation is continued by one rotation (generally, I rotation unit) until the data storage amount in the memory exceeds the reference amount. . Then, when the reference amount is exceeded, intermittent reproduction is performed again. Further, during the above operation, the data processing circuit 211 continues to read data from the memory circuit 209 at a speed corresponding to 1800 rpm and outputs a video signal.

By the above operation, when the programs recorded in different areas on the optical disk are continuously reproduced, the interruption of the image between the programs can be eliminated. Moreover, the number of rotations of the optical disk can be kept constant regardless of the amount of data stored in the memory circuit. Furthermore, it is not necessary to check the amount of data stored in the memory circuit during the intermittent reproduction. Especially since the minimum editing unit can be made smaller than the maximum search time of the optical disc,
The amount of data stored in the memory circuit at the start of intermittent playback is minimal.

In this embodiment, N = 1800 rp
Although the case where m, M = 2200 rpm, and J = 2 has been described, other values may be used, for example, N = 1800 rp.
When m, M = 2200 rpm and J = 4, a reproduction operation for 18 rotations and a still operation for 4 rotations are performed during intermittent reproduction.

In this embodiment, the case where the still operation is performed after the reproducing operation during the intermittent reproduction has been described, but the order of the reproducing operation and the still operation may be any order.

Further, in the present embodiment, the memory control circuit 21
The case where 0 determines whether the data storage amount of the memory circuit 209 exceeds the reference amount has been described, but the system control circuit 207 may perform this.

In this embodiment, one frame of image data is recorded in one track, but other recording formats may be used.

In the present embodiment, the amount of data stored in the memory circuit is compared with the reference amount after the reproduction operation of one rotation (step S2) in the flowcharts of FIGS. It may be performed before the reproducing operation.

Further, in the present embodiment, the case where the still operation of one rotation is repeated twice during the intermittent reproduction has been described.
This is 2 after performing 2 tracks of reverse jump
Scanning for tracks may be performed.

In the present embodiment, the data storage amount of the memory circuit and the reference amount are compared for each one-cycle reproduction operation in the flowcharts of FIGS.
It may be more than rotation.

In this embodiment, the reference amount calculation (steps SX, SY) is performed at the start of reproduction of each program in the flowchart of FIG. 5, but this is calculated for all programs before the start of reproduction. You may stay.

In the present embodiment, the case of the CAV method has been described, but the MCAV method or the ZCAV method may be used.

In the present embodiment, the case where image data is recorded on the optical disk has been described, but this may be other data such as audio.

[0052]

As described above, according to the inventions of claims 1 to 4, when a plurality of programs recorded in different areas on an optical disc are continuously reproduced, the video is interrupted between the programs. Can be output without. Further, regardless of the amount of data stored in the memory circuit, the optical disk may be rotated at a constant speed, which is slightly higher than the recording speed. Moreover, since the amount of data stored in the memory circuit and the reference amount are compared based on the maximum search time of the optical disc device, seamless playback of video and audio is possible no matter how far apart multiple programs are on the optical disc. Can be done smoothly. Further, it is not necessary to compare the data amount with the reference amount during the intermittent reproduction. For this reason, there is an effect that the structure of the optical disk reproducing apparatus is further simplified.

Further, according to the inventions of claims 5 to 8 of the present application,
When a plurality of programs recorded in different areas on the optical disc are continuously reproduced, the video can be output without interruption between the programs. Further, regardless of the amount of data stored in the memory circuit, the optical disk may be rotated at a constant speed, which is slightly higher than the recording speed. Moreover, since the amount of data stored in the memory circuit and the reference amount are compared based on the search time between programs to be connected on the optical disk, the minimum editing unit can be made smaller. Therefore, depending on the arrangement of multiple programs,
It is possible to smoothly perform seamless playback of video and audio more effectively. Further, it is not necessary to compare the data amount with the reference amount during the intermittent reproduction. Furthermore, the capacity of the memory circuit can be smaller.

[Brief description of the drawings]

FIG. 1 is a block diagram of an optical disk reproducing device according to first and second embodiments of the present invention.

FIG. 2 is a schematic diagram of an optical disc used in the optical disc reproducing apparatus of the present invention.

FIG. 3 is a flowchart showing a method of reproducing an optical disc according to the first embodiment of the present invention.

FIG. 4 is a time chart showing a reproducing method of the optical disc in the first embodiment.

FIG. 5 is a flowchart of a method for reproducing an optical disc according to the second embodiment.

[Explanation of symbols]

 201 optical disk 202 motor 203 optical head 204 access control circuit 205 motor control circuit 206 signal processing circuit 207 system control circuit 208 data input control circuit 209 memory circuit 210 memory control circuit 211 data processing circuit

Claims (8)

[Claims] 1. An optical disk, on which data is recorded at a rotation speed N, is rotated at a rotation speed M (> N) to reproduce recorded data, and the reproduced data is written in a memory, which corresponds to the rotation speed N from the memory. An optical disk reproducing method for reading the reproduction data at a speed of, wherein the amount of data read from the memory at a speed corresponding to a rotation speed N within a maximum search time of the optical disk is a reference amount, The amount of data stored in the memory is compared with the reference amount in units of I rotations (I is an integer). If the amount of data storage is equal to or less than the reference amount, data for I rotations is reproduced from the optical disk again. Write the data to the memory, and if the data storage amount exceeds the reference amount, M /
(M−N) × J (J is an integer and M / (M−N) × J
Is an integer value), the reproduction operation of writing the reproduction data of the optical disk to the memory during the rotation is performed N / (M−N) × J rotations, and the reproduction data is not written to the memory J.
An optical disk reproducing method characterized by repeating intermittent reproduction for performing a still operation for rotation. 2. A motor for rotating an optical disk having data recorded at a rotational speed N at a rotational speed M (> N), a motor control circuit for controlling the rotational speed of the motor, and reproducing the recorded data on the optical disk. An optical head, an access control circuit that controls the position of the optical head, a signal processing circuit that demodulates a signal from the optical head, and a memory circuit that temporarily holds the reproduction data processed by the signal processing circuit, A data input control circuit that controls writing and stop of writing of the reproduction data to the memory circuit, a memory control circuit that manages a data storage amount of the memory circuit, and data from the memory circuit at a speed corresponding to a rotation speed N. A data processing circuit for reading out and converting into a video signal or an audio signal, the access control circuit, the motor control circuit, the An optical disc reproducing apparatus comprising: a data input control circuit; and a system control circuit which controls the memory control circuit respectively to seamlessly reproduce data on the optical disc, wherein the system control circuit is within a maximum search time of the optical disc. Further, the amount of data read from the memory circuit at a speed corresponding to the rotation speed N is used as a reference amount, and after the reproduction of the optical disc is started, the data storage amount of the memory circuit and the reference amount are set in I rotation units (I is an integer). If the data storage amount is less than or equal to the reference amount, it is instructed to reproduce the data for I rotations from the optical disk again and write the data to the memory circuit, and the data storage amount is equal to the reference amount. If the amount is exceeded,
M / (M−N) × J (J is an integer and M / (M−N)
During a rotation of (N is a value where J is an integer) rotation, N / (M−N) × J rotations of reproduction operation and J rotations of still operation are repeated, and while the still operation is performed, The optical disk reproducing device, wherein the data input control circuit instructs the memory circuit not to write data. 3. N / (M- during the intermittent reproduction.
2. The optical disk reproducing method according to claim 1, wherein the still operation for J rotations is performed after the reproduction operation for N) × J rotations. 4. N / (M- at the time of the intermittent reproduction.
3. The optical disk reproducing apparatus according to claim 2, wherein a still operation for J rotations is performed after a reproduction operation for N) × J rotations. 5. An optical disc on which data is recorded at a rotation speed N is rotated at a rotation speed M (> N) to reproduce the recorded data, the reproduction data is written to a memory, and the rotation speed corresponds to the rotation speed N from the memory. An optical disk reproducing method for reading the reproduction data at a speed of: from the final address of a first reproduction program recorded first on the optical disk and the first address of a second reproduction program reproduced next to the first reproduction program, The search time from the end of the reproduction of the pre-reproduction program to the start of the reproduction of the post-reproduction program is obtained, and the amount of data read from the memory at the speed corresponding to the rotation speed N within the search time is used as a reference amount to reproduce the optical disc. After the start, the data storage amount of the memory is compared with the reference amount in I rotation units (I is an integer), If the product amount is equal to or less than the reference amount, the data for I rotations is reproduced from the optical disk again, and the reproduction data is written in the memory. If the data storage amount exceeds the reference amount, M /
(M−N) × J (J is an integer and M / (M−N) × J
Is an integer) during rotation, an intermittent operation of performing N / (M−N) × J rotations of reproduction data to be written in the memory and J rotations of still operation in which the reproduction data is not written to the memory. An optical disk reproducing method characterized by repeating reproduction and reproduction. 6. A motor for rotating an optical disc, on which data is recorded at a rotational speed N, at a rotational speed M (> N), a motor control circuit for controlling the rotational speed of the motor, and reproducing recorded data on the optical disc. An optical head, an access control circuit that controls the position of the optical head, a signal processing circuit that demodulates a signal from the optical head, and a memory circuit that temporarily holds the reproduction data processed by the signal processing circuit, A data input control circuit that controls writing and stop of writing of the reproduction data to the memory circuit, a memory control circuit that manages a data storage amount of the memory circuit, and data from the memory circuit at a speed corresponding to a rotation speed N. A data processing circuit for reading out and converting into a video signal or an audio signal, the access control circuit, the motor control circuit, the An optical disc reproducing apparatus comprising: a data input control circuit; and a system control circuit that controls the memory control circuit respectively to seamlessly reproduce data on the optical disc, wherein the system control circuit is a destination recorded on the optical disc. The search time from the end of reproduction of the pre-reproduction program to the start of reproduction of the post-reproduction program is obtained from the last address of the pre-reproduction program to be reproduced in Rotation speed N in time
With the amount of data read from the memory circuit at a speed corresponding to the reference amount as a reference amount, after the reproduction of the optical disc is started, the data storage amount of the memory circuit is compared with the reference amount in I rotation units (I is an integer), If the data storage amount is less than or equal to the reference amount, the data for I rotations is reproduced from the optical disk again to write the data in the memory circuit. If the data storage amount exceeds the reference amount, M / (M
-N) × J (J is an integer and M / (M−N) × J is an integer) During rotation, N / (M−N) × J rotations of the reproduction operation and J rotations are performed. 2. The optical disk reproducing apparatus, characterized in that the intermittent reproduction for performing the still operation is repeated, and the data is not written to the memory circuit during the still operation. 7. N / (M- at the time of the intermittent reproduction.
6. The optical disc reproducing method according to claim 5, wherein a J-rotation still operation is performed after N) .times.J rotation reproduction operations. 8. N / (M- during the intermittent reproduction.
7. The optical disk reproducing apparatus according to claim 6, wherein the still operation for J rotations is performed after the reproduction operation for N) × J rotations.