JP2007048377A - Layer change-over point analyzing apparatus for disk - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a layer change-over point analyzing apparatus for a disk which facilitates work for confirming the change-over point of a multi-layer disk and reduces a burden on an evaluator. <P>SOLUTION: The layer change-over point analyzing apparatus for the disk comprises: analyzing means 9, 16 for retrieving a time map table concerning the recording position of a video title data by acquiring management information, and for analyzing whether or not the table contains a final address showing a point of time when the video title data is changed over from a 1st information recording surface side to a 2nd information recording surface side, when the disk 1 is configured of a two-layer structure; and a control means 16 for converting the final address into a time data from the time map table and controlling a display means 17 to display the time at the final address position on a display screen, when the final address is present. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a disc apparatus for recording / reproducing data on a disc such as a DVD (Digital Versatile Disc) having a plurality of recording layers, and in particular, data recording on one disc is cut from one layer to two layers. The present invention relates to a disk layer switching point analyzing apparatus capable of easily analyzing the time of switching.

A disc such as a CD or DVD having two or more recording / reproducing layers (layers) has a recording track formed in a spiral shape from the inner circumference to the outer circumference or from the outer circumference to the inner circumference. Main data is recorded across the two.
In the popular dual-layer DVD, the video data as the main data is switched to the second information recording surface (second recording layer) side on the first information recording surface (first recording layer) side.

Such a DVD has a slightly different recording track structure depending on the production company. Therefore, when video data is reproduced by a DVD recorder or the like, an unreadable state occurs at the switching point on the first recording layer side, and the reproduced image on the monitor is displayed. There was a problem that a distorted or unstable image was displayed.
For this reason, disk device producers and disk developers need to know in advance whether or not there will be problems with data recording / playback, and various disks were checked and evaluated for suitability. .

In the case of a dual-layer DVD, when video data is recorded in the user data area, the address number of the video title is written corresponding to the time information.
Therefore, a search mode is set in the disk device used for evaluating the DVD, and when this search mode is selected, the recorded information on the DVD is reproduced and the display circuit is controlled so that the reproduction time is displayed on the screen 23a of the monitor 23. I was trying to display it.
For example, when the last address is in the first layer, “00:59:59” indicating 59 minutes 59 seconds is displayed on the screen 23a as shown in FIG. When switching to the second layer, as shown in FIG. 13, “01:00:00” indicating 1 hour 00 minutes 00 seconds is displayed on the screen 23a.
The evaluator pays attention to the time displayed in this way, and grasps the time point when switching from the first layer to the second layer as a switching point of the video data.

However, such a search for a switching point may take a long time since it has to start from the beginning of playback and watch the display time until switching to the second layer.
In addition, since video information is generally composed of a plurality of titles, it is very troublesome to check whether or not the time indicating the final address is displayed in each title on the first layer side. It was something.

By the way, this type of multi-layer disc is prone to have a peculiar problem that does not exist in the single-layer type, and various proposals have been made.
The inventors of the present invention have previously proposed an optical disc apparatus for solving the problem of unstable reproduction when the recording layer for reading data is switched from one layer to the other layer (see, for example, Patent Document 1). .
This optical disk apparatus includes a pickup head, a buffer memory, a reproducing unit, and a servo adjusting unit, as in the popular type. When the data reading layer is switched from one recording layer to the other recording layer, the offset, balance, and gain used to generate the tracking servo signal and focus servo signal supplied to the pickup head are adjusted.
As a result, in the case of a dual-layer DVD, the tracking servo signal and the focus servo signal can be properly maintained with respect to a large change in the reproduction environment that occurs when the data reading layer is switched, and reproduction is unstable. The problem of becoming can be avoided.

In addition, when accessing the other recording surface from the recording surface that is currently being reproduced, the calculation of the pickup movement amount and the control of the movement direction become complicated. There has been proposed a disk reproducing apparatus and method for the purpose (see, for example, Patent Document 2). This means that the rotation angle without deviation between the tracks on the top and bottom of the disk, the means for generating a focus switching command for the pickup, and the sector address detection and access command are used to determine that the access is across different recording surfaces. And a means for calculating the pickup movement amount from the sector address detection and access command, a means for converting the actual movement amount of the pickup from the calculation result, and a means for determining the movement direction, and the like. This allows the focus of the pickup to be switched when a track coincidence point where there is no misalignment between the tracks passes directly above the pickup, so that the track deviation due to the eccentricity between the two recording surfaces in the disc is minimized. Accessible at location. In addition, when accessing across different recording surfaces, it is easy to calculate the amount of movement of the pickup and control the direction of movement.

JP, 10-162377, A Furthermore, the recording medium aiming at setting the address added to information efficiently to recording media, such as CD of multilayered structure, is also known (for example, refer to patent documents 3). ). In this recording medium, common format addresses are continuously added to the main information recorded at the end of the main information recording area of the preceding recording layer and the recording start end of the main information recording area of the recording layer. It has become so. In other words, this is equivalent to a one-to-one correspondence between the main information and the address even in the portion across the layers.

Thereby, the end side address of the main information recording area of the preceding recording layer and the start side address of the main information recording area of the succeeding recording layer are continuous without excess and deficiency, and the addresses of the middle areas other than the main information recording area are The main information recording area is continuously formed.
In addition, even if the layer to be reproduced changes, the decoder or the like does not need to be changed, the reproduction circuit is simplified, and the elapsed time from the start of the program can be easily obtained for the program across the layers. .

JP-A-11-225608

By the way, the inventions of the above-mentioned patent documents 1 and 2 both improve the problems at the time of reproducing a multi-layer disc, and the inefficiency when evaluating the disc by checking the layer switching point cannot be eliminated. .
In the invention of Patent Document 3, the elapsed time from the start of the program can be easily obtained for a program straddling layers, but it is checked whether or not the final address is included in each title on the first layer side. However, it did not know the layer switching point.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a disk layer switching point analysis device that facilitates the task of confirming the switching points of a multilayer disk and can reduce the burden on the evaluator.

In order to achieve the above object, a disc layer switching point analyzing apparatus according to the present invention has a two-layer structure of a first information recording surface and a second information recording surface, and a recording track extends from the inner periphery to the outer periphery of each layer. Or reading means for reading the recorded information from a disc that is formed in a spiral shape from the outer periphery to the inner periphery, records the video title data across each layer, and records the video title management information in the management area; and Means for discriminating whether or not the disc has a two-layer structure from the layer information of the management information read by the means, and when the disc has a two-layer structure, the management information is acquired and the video title data A time map table relating to the recording position is searched, and the time point when the video title data is switched from the first information recording surface side to the second information recording surface side is shown. Analysis means for analyzing whether or not there is an address, and when the final address is present, the final address is converted from the time map table into time data, and the display means is controlled to display the final address position on the display screen. And a control means for displaying the time.
Further, the control means is characterized in that when the final address is present, the information reproduction system is controlled to start reproduction of the video title data from an address immediately before the final address.

As described above, in the disc layer switching point analyzing apparatus according to the present invention, the disc read by the reading means has a two-layer structure, and the video title data is retrieved from the first information recording surface side by searching the time map table. When there is a final address indicating the point of time when switching to the second information recording surface side, this final address is converted into time data and the time of the final address position is displayed on the display screen. There is no need to check the last address while reproducing the disc to know the time of the layer switching point, and the layer switching point of the disc can be easily and easily known in a short time.
In addition, when the control means has the final address, the playback of the video title data is started from the address immediately before the final address, so it is not necessary to start the playback from the beginning and before reaching the layer switching point. There is an advantage that defects can be checked quickly by paying attention to the image of the video title data to be reproduced.

Embodiments of a disk layer switching point analysis apparatus according to the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a block diagram showing an electrical configuration of a disk layer switching point analyzer according to an embodiment of the present invention.
The apparatus of the present embodiment is applied to a DVD recorder, and is configured to reproduce recorded information on the DVD 1 by pressing a remote controller (remote controller) 22 and to record information of external input on the DVD 1. Yes. In this example, description will be made mainly on the playback function.

In FIG. 1, reference numeral 2 denotes a disk tray on which a DVD 1 is placed, and is rotated by a disk motor 3. An optical pickup 4 outputs reproduction information optically read from a track of the DVD 1 to the RF amplifier 5.
The RF amplifier 5 sends reproduction information to a DSP (Digital Signal Processor) 6 and a servo control unit 7 which are signal processing units. The output of the servo control unit 7 is guided to the DSP 6.

These RF amplifier 5, DSP 6, servo control unit 7, and the like are controlled by a microcomputer 9 that reproduces information from the DVD 1 (hereinafter referred to as a front-end microcomputer: FE).
The front-end microcomputer 9 includes a buffer and stores management information read by the optical pickup 4.
When there is an access from the back-end microcomputer 16 described later, management information corresponding to the request is output.
The DSP 6 is connected to a track buffer RAM 8, and temporarily stores data amplified by the RF amplifier 5 and decoded in accordance with the DVD standard (here, compressed by MPEG: Motion Picture Expert Group). It has become.
The DSP 6 is connected to a video encoder 13 and a D / A converter 14 via an AV (Audio / Video) decoder 12.

The servo control unit 7 performs focusing servo and tracking servo control for the optical pickup 4 in accordance with commands and control data transmitted and received from the front-end microcomputer 9 via the DSP 6.
Further, the configuration is such that the sled motor 10 that moves the optical pickup 4 in the radial direction of the DVD 1 and the tray motor 11 that drives the disc tray 2 are controlled.

The AV decoder 12 is connected to a microcomputer (hereinafter referred to as a back-end microcomputer: BE) 16 that performs operation control for outputting various information reproduced from the DVD 1.
The AV decoder 12 decompresses the compressed data by MPEG read from the track buffer RAM 8.
The AV decoder 12 is connected to an AV decode RAM 15 and stores several screens of the digital data expanded as described above.
The video encoder 13 encodes the video data from the AV decoder 12 and sends it to the monitor side (not shown) via the output terminal 13a.
Further, the D / A converter 14 converts the audio data from the AV decoder 12 into an analog signal and sends it to the speaker side (not shown) via the output terminal 14a.

The back-end microcomputer 16 includes a work RAM 16a. The work RAM 16a stores time data corresponding to the address assigned to the track of the user data area.
The back-end microcomputer 16 receives information from the front-end microcomputer 9 and executes processing for analyzing layer switching points.
In this analysis processing, management information of the management area is acquired and a time map table (TMAPT) relating to the recording position of the video title data is searched.

A front panel controller 18 is connected to the back end microcomputer 16. The front panel controller 18 controls the front panel 19 composed of an LCD or the like. The output of the key input unit 20 and the output of the receiving unit 21 that receives an infrared transmission signal from the remote controller 22 are guided.
Further, an OSD (On Screen Display) circuit 17 is connected to the back-end microcomputer 16.
The OSD circuit 17 has an output connected to the video encoder 13 side, outputs an OSD signal based on display control of the back-end microcomputer 16, and displays a menu, a layer switching time, etc. on the screen 23a of the monitor 23 shown in FIG. Is displayed.
At this time, when the back-end microcomputer 16 converts the address information into reproduction time data and outputs it to the OSD circuit 17, the OSD circuit 17 sends out data in units of “hour, minute, second” to the monitor 23 side. The time of the last address is displayed on the screen 23a.

The remote controller 22 includes various operation keys. As the operation keys, a power key for turning on / off the power, an opening / closing key for opening / closing the tray, a numeric keypad, a menu key, a setting determination key, and the like are provided. Various function keys such as play, stop, fast forward and fast reverse keys are also provided.
This function key also serves as a cursor key for selecting a menu item displayed on the screen 23a of the monitor 23.
The menu key outputs a command to display the menu item on the screen 23a of the monitor 23. One of the menu items includes “layer switching time display”.

When this “layer switching time display” is selected, the display mode is entered, and the final address indicating the point at which the main data is switched on the first recording layer side is displayed in time as described above.
The enter key outputs a command for determining the menu item selected according to the operation of the cursor key.
In the remote controller 22 configured as described above, when any key is pressed, information corresponding to the operation content is transmitted to the DVD recorder as a command signal.
When this command signal is led to the back-end microcomputer 16, it controls the operation of the entire DVD recorder together with the front-end microcomputer 9.

Next, a process for evaluating a DVD as an example of a disk will be described.
This DVD 1 has a two-layer structure (DUAL-LAYER) composed of a first information recording surface (first recording layer) and a second information recording surface (second recording layer), and an opposite type (OPPOSITE-TYPE). And two types of parallel type (PARALLEL-TYPE) are known.
In the opposite type, the tracks are provided in a spiral shape from the inner periphery of the first recording layer to the outer periphery, and then from the outer periphery to the inner periphery of the second recording layer. In the parallel type, the tracks are spirally provided from the inner periphery of the first recording layer to the outer periphery, and then from the inner periphery to the outer periphery of the second recording layer.
These DVDs 1 have basically the same data recording structure, and as shown in FIG. 2 (a), are composed of a lead-in area, a user data area, and a lead-out area. The user data area is a first recording layer. And the second recording layer.

Explaining the popular opposite type, the user data area has an increasing value from the outer periphery of the second recording layer to the inner periphery, with the inner periphery of the first recording layer being addressed “0”. It is set as follows.
Therefore, when recording audio / video data (AV data) in the user data area, continuous addresses are added to the continuous AV data.
This address is recorded as address number data corresponding to the elapsed time information from the recording start position of each title (video title data) of the video data.

Therefore, when this address number data is read, the recording start and end positions of each title number (for example, title number 1: TT1) recorded in the user data area of the track, the detailed recording time, etc. It can be displayed on the screen 23a of the monitor 23.
In this user data area, an AV data area is provided between computer data areas, and the AV data is recorded in this area in the smallest sector unit.

This sector is composed of a synchronization signal indicating the boundary between sectors, a sector address indicating the position of the sector on the track, and main data.
All information recorded in the user data area is in file units. The relationship between each data file is managed by a directory structure.
That is, a video object, a picture object, an audio object, a thumbnail object, and the like that mean a collection (group) of information classified for each content (content) is recorded as one AV file in the user data area.

Here, the video object is video data content recording information, and the picture object is still image information such as a still image or a slide image.
The audio object is recording information of content of audio data.
Furthermore, the thumbnail object is reduced image information such as a thumbnail used when searching for a portion to be viewed in the video data or editing.
Therefore, all video information recorded in the AV data area is included in the video object, all audio information is included in the audio object, and all thumbnail information is included in the thumbnail object.

By the way, the minimum basic unit of video information is referred to as a video object unit (VOBU), and data in this VOBU is configured as an aggregate of each VOBU.
These VOBUs are divided and recorded for each sector of 2048 bytes. Each sector is recorded in a pack structure format.
That is, raw video information, sub-video information, audio information, and dummy information are recorded in each pack format for each pack.

On the other hand, at the time of reproduction, a reproduction procedure is recorded in the reproduction control information (pack control information), and an arbitrary range in an arbitrary VOB can be designated and reproduction can be performed in an arbitrary reproduction order.
Therefore, when playing back video data, the playback procedure described in the playback control information can specify a range in an arbitrary VOB and play back in an arbitrary playback order. The basic unit of video information at the time of reproduction is also called a cell.
Information indicating the video information playback sequence is set by a program chain (PGC). This reproduction sequence is described by designation of one cell or connection information of a plurality of cells.
Here, PGC indicates a unit for executing a series of playbacks in which the playback order of the cells is specified, and the cell indicates a playback section in which playback data in each VOB is specified by a start address and an end address.

The lead-in area has an emboss data area and a management area as shown in FIG.
In the emboss data area, as shown in FIG. 2 (c), the entire disk such as the layer information, the type of one or two layers, the disk type, the disk size, the recording density, the physical sector number indicating the recording start / end position, etc. And other information related to manufacturing one by one are recorded in advance.
Further, management information related to the main data is recorded in the management area. When the main data is video data, a video title set map table (abbreviation: VTS.TMAPT) is generated as management information.
And this VTS. In the TMAPT, the start address (abbreviation: VTS.TMAPT.SA) of the video title set map table from the title (TT) 1 is described.

FIG. 3 is an explanatory diagram showing a data recording example of a video title set map (VTS.TMAP).
That is, each title (TT) of video data is composed of a time unit (TMU), a reservation (RESERVED), the number of map entries (MAP.EN.Ns), and a map entry table (MAP.ENT).
Here, TMU is in seconds, indicating the time interval of the map entry, and the number of bytes is 1. RESERVED has 1 byte, and MAP. EN. Ns has 2 bytes.
Also, MAP. For EN, the number of bytes is 4 x the number of map entries. This MAP. EN indicates the VOBU of each map entry destination.

FIG. 4 is an example of a time unit (TMU).
In the figure, the map entry number at the head position of the program chain (PGC) is “0”, and the reproduction time is also “0” as a reference point.
Here, when the TMU is set at an interval of 2 seconds, for example, the number of map entries is an integer multiple of 2, and a maximum of 2048 can be set.
Since the reproduction time information corresponds to the map entry number, the map entry number 1 is recorded as 2 seconds, the number 2 is 4 seconds, the number 4 is 6 seconds, and so on.
Therefore, the address information indicating the position of this map entry number can be converted into time data.
As a result, when the address information is acquired, it is possible to easily know the time of the position in units of “hour, minute, second”.

Next, the operation of the disk layer switching point analyzer will be described with reference to the drawings.
FIG. 5 is a main routine of a process for displaying the layer switching point in time.
First, when the evaluator checks the disc, the DVD 1 to be evaluated is set on the tray of the DVD recorder.
Then, the remote controller 22 is operated, and the menu is displayed on the screen 23a of the monitor 23 by the menu key, and “display layer switching time” is selected from the menu items.

Along with this, the microcomputers 9 and 16 shift to the layer switching time display mode, and the front end microcomputer 9 operates the optical system.
First, when the optical pickup 4 reads management information from the lead-in area of the DVD 1, it is sent from the RF amplifier 5 to the front-end microcomputer 9 side.
When the front-end microcomputer 9 acquires the management information, the front-end microcomputer 9 stores it in the buffer.

Next, the back-end microcomputer 16 accesses the front-end microcomputer 9 and acquires layer information (step S11). Then, it is determined whether the DVD 1 is one layer or two layers (step S12).
Here, if the DVD 1 has a single layer, the process proceeds to step S18, where the OSD signal is output from the OSD circuit 17, and the screen 23a of the monitor 23 displays that the DVD 1 is not of a two-layer structure.

On the other hand, if the DVD 1 has two layers, title information is acquired from the front-end microcomputer 9 (step S13). Then, the address information is converted into time data from the first title (step S14).
Subsequently, it is determined from this title information whether or not the layer information on the first layer side has a final address (step S15).
If there is a final address, the process proceeds to step S18, where the OSD signal is output from the OSD circuit 17, and the time of the final address is displayed on the screen 23a of the monitor 23 as shown in FIG.
This display content indicates that the DVD 1 has a two-layer structure, is of the opposite type, has a layer switching point in the title 1, and its time is 58 minutes 22 seconds.

On the other hand, if the title has no final address, the number of titles is counted up (step S16), and it is determined whether or not all title information of this DVD 1 has been acquired (step S17).
At this time, if all the title information is not acquired, the process proceeds to step S13, and the next title information is acquired.
Then, after the processing of steps S14 to S16 as described above, it is determined whether or not all title information has been acquired in step S17.
When all the title information is acquired by repeating such processing, a sign indicating that there is no final address is displayed on the screen 23a as shown in FIG.
This display content indicates that there is no layer switching point in all titles.
Thus, the evaluator can easily know whether or not there is a layer switching point in the first layer without having to reproduce the DVD 1 from the beginning.

Next, each process in the disk layer switching point analyzing apparatus will be described with reference to the drawings.
FIG. 6 is a flowchart of a process for changing the address information to time.
That is, in step S13 of the main routine, the title information is analyzed after it is determined that the DVD 1 has a two-layer structure.
The back-end microcomputer 16 acquires the video title set time map table information (VTS.TMAP.TI) from the front-end microcomputer 9 (step S21).
Then, the corresponding address is checked from this VTS.TMAP.TI (step S22).

Next, after obtaining the time unit (TMU) (step S23), the map entry (MAP.EN) number is obtained (step S24).
Subsequently, the address information is converted into time data based on the MAP.EN number (step S25).
As a result, the layer switching point time can be obtained from VTS.TMAP.TI.

Next, the video title set time map table (VTS.TMAP.T
) Search processing will be described.
FIG. 7 is an explanatory diagram showing a process of searching for VTS.TMAP.T.
Here, in step S15 of the main routine, a process for searching whether or not there is a final address as a layer switching point on the first layer side of the DVD 1 is performed.
In this search process, the back-end microcomputer 16 accesses the front-end microcomputer 9 and acquires video title set time map table information (VTS.TMAP.TI).
First, when this VTS.TMAP.TI is obtained, the video title set time map # 1 (VTS.TMAP.SRP # 1) is used by the video title set time map # 1 search pointer (VTS.TMAP.SRP # 1). Search for .TMAP # 1).

Next, the video title set time map # 2 (VTS.TMAP # 2) is searched by the video title set time map # 2 search pointer (VTS.TMAP.SRP # 2).
Such search processing continues until the final address information is detected, but the last video title set by the video title set time map #n search pointer (VTS.TMAP.SRP # n). End when time map #n (VTS.TMAP # n) is executed.

Next, information processing for converting the address information into time data will be described with reference to the drawings.
FIG. 8 is a flowchart showing a process for obtaining a map entry (MAP.EN) number.
Here, after obtaining the above VTS.TMAP.TI shown in FIG. 7, whether or not there is final address information is compared by calculation to perform processing for conversion to time data.
First, as shown in FIG. 9, the back-end microcomputer 16 starts information acquisition from the time point of the MAP.EN number “0” and sets “i = 0” (step S31).
Next, in order to check the corresponding final address, a calculation process according to the following equation (1) is performed (step S32).
MAP.EN [i] <first final address <MAP.EN [i + 1] (1)

For example, the number of MAP.EN [i] is “1000”, the address data is “300000”, the number of MAP.EN [i + 1] is “1001”, and the address data is “300020”.
Here, if there is a first final address, the address data is calculated as “300010”.
At this time, the process proceeds to step S35, and the address is converted into time data. If the time corresponding to the address “300010” is 00:58:22, “00:58:22” is displayed on the screen 23a of the monitor 23 as described above. And a series of operation | movement is complete | finished.

On the other hand, if there is no first final address, the upper MAP.EN number “i ++” is acquired (step S33).
Subsequently, whether or not the MAP.EN number is the maximum MAP.EN number is calculated by the following equation (2) (step S34).
i <MAP.EN. Ns (2)
As a result, if it is lower than the maximum MAP.EN number, the process proceeds to step S32 and the corresponding final address is checked again.
Such arithmetic processing is continued, and when the final address exists between MAP.EN [i] and MAP.EN [i + 1], it is converted into time data.
On the other hand, when the final address is not detected, the arithmetic processing is continued until immediately before the maximum MAP.EN number, and then the series of operations is terminated.

As described above, when the evaluator selects the layer switching point analysis mode, the time of the last address is displayed on the screen 23a of the monitor 23. At this time, it is not necessary to reproduce the DVD 1 and display can be performed within a few seconds from the time of operation. Therefore, it is easy to confirm the switching point of the multilayer disk, and the burden on the evaluator can be reduced.

This DVD recorder can set a playback check mode in the menu in addition to the layer switching point analysis mode.
When the evaluator selects this playback check mode, when the back-end microcomputer 16 has a final address on the first layer side, playback of video title data is started from the address immediately before this final address.
Then, the reproduced image immediately before the final address is displayed on the screen 23a of the monitor 23. For this reason, it is not necessary to reproduce the image from the beginning, and it is possible to quickly check for defects by paying attention to the image to be reproduced before reaching the layer switching point.
In addition, this apparatus is not limited to said each embodiment, A various change is possible in the range which does not deviate from the meaning of this invention.

It is a block diagram which shows the electric constitution of the layer switching point analysis apparatus of the disk which is one Embodiment of this invention. It is a schematic explanatory drawing which shows the data structure of a disc. It is explanatory drawing which shows the data recording example of a video title set map. It is an illustration figure of a time unit. It is a main routine of a process for displaying a layer switching point in time. It is a flowchart of the process which changes address information to time. It is a flowchart which shows the acquisition process of a video title set time map table. It is a flowchart which shows the acquisition process of a map entry number. It is a time chart which shows the relationship between a map entry number and time. It is the screen figure which displayed the time of the layer switching point. It is the screen figure which displayed the state without a layer switching point. It is a screen figure by the side of the 1st layer concerning the conventional layer switching point display. It is a screen figure of the same 2nd layer side.

Explanation of symbols

1 disk 9, 16 analysis means 16 control means

Claims (2)

The first information recording surface and the second information recording surface have a two-layer structure, and a recording track is formed in a spiral shape from the inner periphery to the outer periphery direction of each layer or from the outer periphery to the inner periphery direction. Reading means for recording the title data and reading the recorded information from the disc for recording the management information of the video title in the management area;
Discriminating means for discriminating whether or not the disc has a two-layer structure from the layer information of the management information read by the reading means;
When the disc has a two-layer structure, the management information is acquired and a time map table relating to the recording position of the video title data is searched, and the video title data is second information from the first information recording surface side. An analysis means for analyzing whether or not there is a final address indicating a time point when switching to the recording surface side;
A control means for converting the final address from the time map table into time data when the final address is present, and for controlling the display means to display the time at the final address position on the display screen. Layer switching point analyzer. 2. The control unit according to claim 1, wherein when the final address is present, the control unit controls the information reproduction system to start reproduction of the video title data from an address immediately before the final address. Disc layer switching point analysis device.