JP2001078139A - Recording medium and video reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a recording medium and a video reproducing device that can correctly reproduce a recorded video image for only a user who legally receives supply of the recording medium from a software supplier. SOLUTION: An optical disk 1 records information of a main video image and information of a sub video image other than the main video image and records information that is forcibly displayed to disturb normal reproduction display of the main video images as at least part of the information of the sub video image. The video reproducing device that reproduces the video image from this optical disk 1 is provided with a sub video image forced display release circuit 17 that releases the forced display of the sub video image on a monitor 14 via a sub video image display control circuit 15 and a main/sub video image mixer circuit 13 according to a sub video image display release flag 18 to release the forced display of this sub video image, and only a legal user can normally reproduce and display the main video image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording medium such as a DVD on which encoded video information, audio information, character information, etc. are recorded. The present invention relates to a recording medium on which video information is recorded. Further, the present invention relates to a video reproducing apparatus for reproducing a video from such a recording medium.

[0002]

2. Description of the Related Art DVDs and their reproducing apparatuses have been developed as large-capacity recording media on which information such as digital video data and audio data can be recorded. DVDs have higher image quality than conventional packaged media such as video tapes and laser disks, and have superior operability such as faster random access, and new functions such as multi-angle and parental control are added. Thus, various digital images can be reproduced.

[0003] Video information recorded on a DVD includes main video information, which is a normal moving image, and sub-video information used for character information and the like. The sub-picture information can be turned on / off by the user or forced to be displayed by the software provider, and is mainly used for menus such as subtitles for movies, karaoke lyrics, and title information. Have been.

[0004] By the way, in spite of the fact that DVDs can record video information such as movies for a long time and with high image quality, a provider as a software provider restricts the number of times of reproduction on a DVD player owned by a user. No such measures have been taken. In other words, the conventional DVD software can be reproduced without limitation, regardless of whether or not the user has provided the user from the software provider, which is not preferable from the viewpoint of copyright protection.

As a countermeasure, for example, a system for charging for the use of DVD software using a DVD player is conceivable. However, since the current DVD player is a system that only considers the reproduction of package media, a charging function must be incorporated. Is not easy on the system. Further, if a DVD player having such a charging function is newly constructed as a system, the system becomes very expensive.

[0006]

As described above, the conventional DVD and its reproducing apparatus have a problem that anyone can reproduce from a recording medium as a package medium, which is not preferable from the viewpoint of copyright protection. Was.

[0007] The present invention provides a recording medium capable of correctly reproducing an image recorded only by a user who has been provided with a recording medium from a software provider, and a video reproducing apparatus for correctly reproducing an image from the recording medium. The purpose is to do.

[0008]

In order to solve the above-mentioned problems, the present invention provides a recording medium on which information of a main video which is a main moving image and information of other sub-videos is recorded. As a part, information forcibly displayed so as to prevent normal reproduction and display of the main video is recorded.

[0009] More specifically, information indicating that a sub-picture forcibly displayed on the recording medium is forcibly displayed so as to prevent normal reproduction and display of the main picture, and cancellation of the forced display based on the information. Information indicating that it is possible is recorded as display control information.

[0010] In the recording medium on which the information of the main image and the sub-image is recorded as described above, the image reproduction having the function of canceling the forced display of the sub-image information forcibly displayed so as to prevent the normal reproduction and display of the main image is prevented. Only the device can normally reproduce and display the main video.

[0011] Specifically, in this video reproducing apparatus, information (key information) for canceling the forced display of the sub-picture which is forcibly displayed so as to prevent normal reproduction display of the main picture is input, The main video is configured to be normally reproduced and displayed. In other words, it is possible that only a legitimate user who has received the key information from the software provider who has received the recording medium from the software provider can correctly reproduce the main video recorded on the recording medium using this video reproducing apparatus. Become.

The information of the sub-picture forcedly displayed so as to prevent the normal reproduction and display of the main picture may be recorded so as to prevent the normal reproduction and display of the main picture except for a certain period of time. The video may be recorded so as to prevent the reproduction display of the video only for a specific part of the main video.

Further, the video reproducing apparatus according to the present invention cancels the forced display of the sub-video which is forcibly displayed so as to prevent the normal reproduction and display of the main video until the number of times of reproduction from the recording medium reaches a predetermined number. By doing so, the main video may be normally reproduced and displayed.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 is a block diagram showing a configuration of a video reproducing apparatus according to a first embodiment of the present invention. This video playback device is a device that plays back video and audio accompanying the video from an optical disc 1 such as a DVD as a recording medium, and includes a spindle motor 2, an optical head 3, a motor control circuit 4, a playback signal processing circuit 5, Demultiplexer 6, video buffer 8, sub-picture buffer 9, main control circuit 10,
It comprises a main video decoder 11, a sub video decoder 12, a main / sub video mixing circuit 13, a monitor 14, a sub video display control circuit 15, and a sub video forced display release circuit 17.

Here, the point that a sub-picture forced display canceling circuit 17 is provided is different from the conventional picture reproducing apparatus.
The sub-picture forced display release circuit 17 is provided with a sub-picture forced display release flag 18 as described later,
This is for canceling the forced display of the sub-picture on the monitor 14.

First, before describing the video reproducing apparatus in detail, an optical disc 1 according to the present embodiment will be described. There are various types of optical disks,
Above all, for example, a read-only DVD having a double-sided bonding structure has a capacity of less than 5 Gbytes, and can record a large amount of digital video information and digital audio information. As digital video information, it is possible to record high-quality, large-capacity video information mainly by recording video data compressed according to the MPEG2 standard or the like. The optical disc 1 in the present embodiment is, for example, such a read-only DVD.
It is.

FIG. 2 is a diagram showing a recording format on the optical disk 1. On the optical disc 1, information of a main video which is a main moving image and information of some other sub-videos are recorded. In FIG. 2, a video stream 30 is a video pack 3 in which main video information is recorded.
1. It is composed of a sub-picture pack 32 in which sub-picture information is recorded and an audio pack 33 in which audio information is recorded.

The video pack 31 divides video data compressed according to, for example, the MPEG2 standard into data units of a specific length. Audio pack 33 is likewise MP
Audio data compressed in accordance with the EG2 standard or digital PCM data is recorded as it is in an uncompressed mode, and the audio data is recorded by being divided into data of a specific length. In this case, the video pack 31, the sub-picture pack 32, and the audio pack 33 are recorded in the video stream 30, but it is not always necessary to record all these packs. It may be recorded in.

The sub-picture stream 40 is a set of sub-picture packs 32 included in one video stream 30. That is, one sub-picture stream 40 is formed by joining the sub-picture packs 32 in the video stream 30.

The sub-picture stream 40 includes a sub-picture header 4
1 and sub-picture display pixel data 42 and a sub-picture display sequence 43. Information such as the data capacity of the sub-picture stream 40 is recorded in the sub-picture header 41. The sub-picture display pixel data 42 is data in which, for example, menu information for menu display, character information such as movie subtitles, and the like are encoded as pixel data by a specific run-length encoding method. The sub-picture display control sequence 43 is data for controlling the display of the sub-picture in time series, and is composed of a display control command group for controlling the display of the sub-picture pixel data 42 in time series.

As shown in FIG. 3, the display control command group in the present embodiment includes the following commands. -"Forced display start command" for forcibly setting the display start timing of the sub-picture display pixel data 42-"Forced display release enable command" indicating that the forced display of the sub-picture display pixel data 42 can be released "Display start command" and "display stop command" for setting the display start timing and display stop timing of the sub-image display pixel data 42 within a certain period of time.-Set the display color code of the sub-image display pixel data 42. "Color setting command" for setting the "mixing ratio setting command" for setting the mixing ratio between the sub-picture display pixel data 42 and the main picture display pixel data.-For setting the display area of the sub-picture display pixel data 42. "Area setting command"-"Area start position setting command" for setting the display start address of the sub-picture display pixel data 42-Sub-picture A "color / mixing ratio change command" for setting a change in the color and the mixing ratio of the display pixel data 42 A "display end command" for instructing the end of the display control command group Here, the optical disc of the present embodiment 1 is different from the related art in that the display control command group is recorded as follows.

First, in addition to the recording of a "forced display start command" for forcibly displaying a sub-picture in the display control command group, a signal indicating whether or not the forced display can be canceled is also displayed. The feature is that the "command for canceling forced display" is also recorded. "Command for canceling forced display"
May be recorded in the form of a flag. It is assumed that this “command for canceling forced display” (or flag) is recorded in a format that does not cause any particular problem even when the conventional video reproducing apparatus reproduces data from the optical disk 1.

Second, in the present embodiment, the main video / sub-video mixing ratio set by the "mixing ratio setting command" is set so that, for example, the main video is always displayed at 0% and the sub-video is displayed at 100%. You.

Third, in the present embodiment, the same value as the size of the main video screen is recorded in the sub-video display pixel area indicating the display area of the sub-video on the main video set by the "area setting command". .

Fourth, as the sub-picture display pixel data 42, pixel data in which the sub-picture fills and covers the entire main picture screen is recorded.

Next, the video reproducing apparatus of this embodiment shown in FIG. 1 will be described. Various information is recorded on the optical disc 1 as described with reference to FIGS. When reproducing from the optical disk 1, the optical disk 1 is driven to rotate by a spindle motor 2, and information recorded on the optical disk 1 in the form of a pit train or the like is read by the optical head 3. The rotation of the spindle motor 2 is controlled by the motor control circuit 4 under the control of the main control circuit 10.

A reproduction signal obtained by reading information on the optical disk 1 by the optical head 3 is inputted to a reproduction signal processing circuit 5, where processing such as amplification, equalization, binarization, decoding and error correction is performed. As a result, the video stream 30 shown in FIG. 2 is reproduced. This video stream 30
Are input through a buffer 6 to a demultiplexer 7 for separating information by type.

In the demultiplexer 7, when the video stream 30 is a video pack 31 indicating main video information, the video pack 31 is distributed to the video buffer 8, and the main video decoder 11
Is input to The main video decoder 11 decodes (decompresses) the compressed video data of the video pack 31 to generate the original main video data.

On the other hand, when the video stream 30 is a sub-picture pack 32, the sub-picture pack 32 is distributed to the sub-picture buffer 9 by the demultiplexer 7, and is input from the sub-picture buffer 9 to the sub-picture decoder 12. The sub-picture decoder 12 assembles the sub-picture packs 32 as a sub-picture stream 40 as shown in FIG. 3, decodes the run-length encoded sub-picture display pixel data from the sub-picture stream 40, and Generate

The sub-picture data generated by the sub-picture decoder 12 is combined with the main picture data generated by the main picture decoder 11 by the main / sub-picture mixing circuit 13 and then supplied to the monitor 14. In the sub-picture decoder 12, the display control command group shown in FIG. 3 is also generated. This display control command group is supplied to the sub-picture display control circuit 15 and the sub-picture forced display canceling circuit 17.

In the sub-picture display control circuit 15, the "mixing ratio setting command" shown in FIG.
In accordance with the “color setting command” and the “region setting command”, the mixing ratio of the main video data and the sub video data in the main / sub video mixing circuit 13 and the color and position of the sub video on the main video are controlled. Further, when the "forced display start command" of FIG. 3 is recorded, the sub-picture display control circuit 15 controls the main / sub-picture mixing circuit 13 so that the sub-picture is forcibly displayed on the main picture. .

That is, when the “mixing ratio setting command” has been set, the main / sub-video mixing circuit 13 controls the mixing ratio of the main video data and the sub-video data under the control of the sub-video display control circuit 15. The mixing is performed according to a fixed ratio calculated from the mixing ratio setting value indicated by the “mixing ratio setting command” to generate a composite image. In this case, the position in the main video at which the sub-video is to be displayed is determined according to the “region setting command”. When the “mixing ratio setting command” is not set, the main / sub-image mixing circuit 13 is controlled by the sub-image display control circuit 15 so that only the main image is displayed on the monitor 14.

On the other hand, when displaying a sub-picture other than the above display control command group, the user sub-picture display control flag 1
The display control is performed by the sub-picture display control circuit 15 in accordance with 6. For example, when displaying the user menu screen, when the user sub-video display control flag 16 is input as valid (ON), a composite image of the main video and the sub-video is output to the monitor 14. In this case, the main / sub-image mixing circuit 13 is controlled by the sub-image display control circuit 15 so that the composite screen of the sub-image and the main image is displayed on the monitor 14.

The user sub-picture display control flag 1
When 6 is invalidated (off), the main / sub-image mixing circuit 13 is controlled by the sub-image display control circuit 15 so that only the main image is displayed on the monitor 14. The operation up to this point is the same as the case where the reproduction is performed from the conventional optical disc by the conventional video reproducing apparatus.

On the optical disk 1 recorded according to the present invention, as shown in FIG. 3, the sub-picture display start timing by the sub-picture display pixel data 42 is forcibly set as a part of the display control command group. Compulsory display start command "is recorded, and the sub-picture display pixel data 42
Is data in which the sub-picture covers the entire screen of the main picture. The sub-picture display control circuit 15 controls the main / sub-picture mixing circuit 13 based on the “forced display start command” so that the sub-picture is always displayed on the monitor 14, so that the main picture can be displayed normally. Hinder.

On the optical disk 1 recorded according to the present invention, the forced display of the sub-picture by the sub-picture display pixel data 42 can be canceled as a part of the display control command group as shown in FIG. Is also recorded (or flag). By setting the “compulsory display release enable command”, in the video reproducing apparatus of the present embodiment, when the sub-video forced display release flag 18 is given to the sub-video display release circuit 17, the sub-video display release circuit 17 It is possible to cancel the forced display of the sub-picture.

That is, when the sub-picture display canceling circuit 17 confirms that the "command for canceling forced display" (or flag) is present in the display control command group reproduced from the optical disc 1, the sub-picture display canceling circuit 17 receives the sub-command from the user. The sub-picture display control circuit 15 is controlled so that the forced display of the sub-picture is released according to the input of the video forced display release flag 18 and the display of the sub-picture is stopped. As a result, the main video / sub-video mixing circuit 1
In step 3, only the main video data is output to the monitor 14, and finally only the main video is displayed on the monitor 14.

As described above, in the video reproducing apparatus of the present embodiment, when reproducing from the optical disc 1 on which the "forced display release enable command" (or flag) is recorded according to the present invention, the sub-video forced display release flag 18 is set. By inputting, the forced display of the sub-picture can be canceled by the sub-picture display canceling circuit 17 and only the main picture can be displayed. Therefore, only the authorized user who can input the sub-picture forced display release flag 18 can correctly display the main picture. You can play it.

On the other hand, when the conventional video reproducing apparatus without the sub-picture display releasing circuit 17 reproduces from the optical disc 1 according to the present invention, the forced display of the sub-picture cannot be released. A sub-image that hinders playback display is displayed. In other words, a user other than a regular user who has a right to play back from the optical disc 1
, The main video cannot be reproduced normally.

On the other hand, the video playback apparatus of the present embodiment can perform normal playback when playing back from a conventional optical disc on which a "forced display release enable command" (or flag) is recorded. Nor.

(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
It is a block diagram which shows the structure of the video reproduction apparatus concerning embodiment. In FIG. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals, and differences from the first embodiment will be described. In this embodiment, in addition to the configuration of the first embodiment, a password input 20 A sub-video display release flag generation circuit 19 that generates a sub-video display release flag 18 based on the sub-display is added.

Hereinafter, the processing procedure at the time of video reproduction of this embodiment will be described with reference to the flowchart shown in FIG. First, when the video playback is started, a request is issued to the user of the video playback apparatus to prompt a password input 20 for generating a sub-video display release flag 18 for releasing the forced display of the sub-video (step). S11). Here, it is assumed that a user (authorized user) who has a right to play back from the optical disk 1 has previously obtained a password for generating the sub-video display release flag 18 from a software provider such as a provider.

In response to this request, when the password is input by the authorized user in step S12, the sub-picture display release flag generation circuit 19 determines whether the password is correct. If the password is correct, the sub-picture display release flag is generated. 18 is generated. Thereafter, as in the first embodiment, it is confirmed that the "forced display release enable command" (or flag) is present in the display control command group reproduced from the optical disc 1 by the sub-video display release circuit 17. Thereafter, the sub-picture display control circuit 15 controls the sub-picture display control circuit 15 to cancel the forced display of the sub-picture and stop the display of the sub-picture according to the sub-picture forced display release flag 18 generated by the sub-picture display release flag generation circuit 19. Then, only the main video data is output from the main video / sub-video mixing circuit 13 to the monitor 14, whereby the main video is reproduced and displayed on the monitor 14 (step S14).

On the other hand, the sub-picture display release flag generation circuit 19
If it is determined that the password is not correct, the sub-picture display release flag 18 is not generated, so that the sub-picture display control circuit 15 supplies the sub-picture data to the monitor 14 based on the "forced display start command". By controlling the main / sub-video mixing circuit 13, the sub-video is displayed on the monitor 14, and the main video is not reproduced and displayed (step S10).
15).

Then, until it is determined in step S16 that the reproduction of the main image in step S14 or the display of the sub-image in step S15 has been completed, the process proceeds to step S11.
Steps S14 and S15 are performed.

As described above, the sub-picture forced display canceling flag 18 is generated in accordance with the password input 20 by the authorized user, and the sub-picture display canceling circuit 17 cancels the sub-picture forced display based on this to display the main picture. ,
Only the authorized user who has obtained the password can correctly reproduce the main video.

(Third Embodiment) As described in the second embodiment, the generation of the sub-video display release flag 18 in the sub-video display release flag generation circuit 19 is based on key information such as a password. It can be carried out.

For example, if the key information can be obtained from a source other than the optical disk 1, the software provider sends the key information only to the authorized user who has paid the predetermined fee, or sends the key information to the The key information may be sent to the user separately from the optical disk 1 in accordance with a request from the user. Therefore, only the authorized user given the key information generates the sub-picture display release flag 18 in accordance with the password, and cancels the sub-picture forced display by the sub-picture forced display release circuit 17 to display the main picture correctly. It is possible.

FIG. 6 is a block diagram showing a configuration of a video reproducing apparatus according to the third embodiment of the present invention based on such a concept. In FIG. 6, the same parts as those in FIG. 4 are denoted by the same reference numerals, and differences from the second embodiment will be described. In the present embodiment, a random number generation circuit 21 is added to the configuration of the second embodiment. The random number 22 generated here is supplied to the sub-picture display release flag generation circuit 19.

Hereinafter, the processing procedure at the time of video reproduction of this embodiment will be described with reference to the flowchart shown in FIG. First, when video reproduction is started, a random number generation circuit 21 generates a random number 22, which is a sub-video display release flag generation circuit 19, a sub-video forced display release circuit 17, a sub-video display control circuit 15, and a main / sub-video Monitor 1 through mixing circuit 13
4 and displayed on the monitor 14 (step S2
1). The random number 22 generated by the random number generation circuit 21 is also sent to the software provider of the optical disc 1.

Next, a sub-picture display cancel flag 1 for canceling the sub-picture forced display to the user of the picture reproducing apparatus.
A request for prompting a password input 20 for generating the password 8 is issued (step S22). In response to this request, the user (authorized user) pays a predetermined fee to the software provider to obtain a password, and performs a password input 20 to the sub-picture display release flag generation circuit 19 (step S23).
The password sent from the software provider is displayed on the menu screen at the same time when the sub-picture is displayed on the monitor 14, and the authorized user can obtain (recognize) the password by looking at the menu screen. .

In response to the request issued in step S22,
In step S23, the password input 20 by the authorized user
Is performed, the sub-image display release flag generation circuit 19 determines whether or not the password is correct. If the password is correct, the sub-image display release flag 18 is generated.

Then, after the sub-picture display canceling circuit 17 confirms that the "command for canceling forced display" (or flag) exists in the display control command group reproduced from the optical disc 1, the sub-picture is canceled. Sub-video forced display release flag 18 generated by display release flag generation circuit 19
, The sub-picture display control circuit 15 is controlled so that the forced display of the sub-picture is released and the display of the sub-picture is stopped.
By outputting only the main video data from the main video / sub-video mixing circuit 13 to the monitor 14, the main video is reproduced and displayed on the monitor 14 (step S25).

On the other hand, the sub-picture display release flag generation circuit 19
If it is determined that the password is not correct, the sub-picture display release flag 18 is not generated, so that the sub-picture display control circuit 15 supplies the sub-picture data to the monitor 14 based on the "forced display start command". By controlling the main / sub-video mixing circuit 13, the sub-video is displayed on the monitor 14, and the main video is not reproduced and displayed (step S10).
26).

Next, in step S27, step S27 is executed.
After it is determined that the reproduction of the main image in step S25 or the one-time display of the sub-image in step S26 is completed, step S2 is performed.
Step S21 until it is determined that all the reproductions are completed in Step S8
To S27 are repeatedly performed. That is, the random number generation circuit 21 generates a random number 22 each time one display of the main video (for example, display of one movie) is completed, and the user is required to input a password each time.

As described above, according to the present embodiment, for example, only the authorized user who has paid the predetermined fee obtains the password (key information) given by the software provider and performs the password input 20 and forcibly displays the sub-picture. The release flag 18 is generated, the forced display of the sub-video is released by the sub-video display release circuit 17, and the main video can be displayed.

Therefore, in this embodiment, it is possible to construct a system for charging each time the main video is displayed and reproduced once. However, in order to do so, it is necessary that the system be configured so that the password can be changed each time the main video is displayed and reproduced once. further,
It is preferable that the password be encrypted in order to prevent unauthorized use of the video device.

More specifically, as described above, as a method of delivering passwords and key information only to authorized users, a public encryption key, which is widely used in network technology in recent years, is used to quickly send passwords and keys via a network. A method of distributing information or a method in which the video reproducing apparatus itself has a function of decoding an encryption, and a software provider directly sends a password or key information to the video reproducing apparatus via a network or the like can be considered. However, the method of transmitting the password and the key information to the authorized user is not particularly limited, and any method may be used.

The present invention is not limited to the above embodiment, but can be implemented with various modifications as follows, for example. (1) The “forced display cancelable command” (or flag) indicating whether the forced display shown in FIG. 3 can be canceled may be recorded at any position on the optical disc 1.

For example, this “command for canceling forced display” (or flag) is one of the sub-picture display control sequence 43, sub-picture header 41 and sub-picture display pixel data 42 in the same sub-picture stream 40 shown in FIG. It may be recorded in the department. Further, this “command for canceling forced display” (or flag) may be recorded in a private stream. Further, a "forced display cancelable command" (or flag) may be recorded at a position where control information or data for title display is recorded.

In these cases, it is necessary for the video reproducing apparatus to configure a decoding circuit corresponding to the recording method of the "command for canceling forced display" (or flag). For example, in the above embodiment, the “forced display cancelable command” (or flag) is recorded in the sub-video display control sequence 43 as a part of the display control command group.
2 could be decoded, but if a "forced display cancelable command" (or flag) was recorded in the private stream, a decoding circuit for the private stream must be newly added. Must.

(2) In the above embodiment, the description of the sub-picture information in the form that hinders the display of the main picture is data such that the sub-picture covers the entire main picture. Similar effects can be obtained with sub-picture information covered by sub-pictures. For example, as information of a sub-image to be forcibly displayed, an image in which only a certain part of the screen is displayed in a grid shape is used so that a target object (for example, a person's face) on the main video is not visible. Record.

When the reproduction is performed from the recording medium on which the sub-picture information is recorded, the conventional picture reproducing apparatus reproduces a grid-like sub-picture on the face of a person as an object of interest, and Cannot see the person's face, and is meaningless as the main image. In contrast, the use of the video reproducing apparatus of the present invention makes it possible to reproduce the entire screen including the face of a person on the main video.

(3) Contrary to the above, only a part of the main image may be displayed, and information on the sub-image may be recorded on the recording medium so that the sub-image prevents display of the main image. . For example, the main image is displayed only on a circular screen, and the sub-image information is recorded on the recording medium such that the surrounding area is covered with the sub-image.

When reproduction is performed by the conventional video reproducing apparatus from the recording medium on which the sub-video information is recorded as described above,
Although only the main video within the circle can be viewed, full-screen reproduction of the main video can be performed by the video reproduction device of the present invention.

(4) The mixing ratio of the main picture and the sub-picture which hinders the display of the main picture can be set arbitrarily.
For example, the information of the sub-picture is configured so that the main picture can be seen slightly, and the mixing ratio of the main picture and the sub-picture is set to, for example, 20% of the main picture and 80% of the sub-picture, and the recording medium Record. When reproducing from this recording medium with a conventional video reproducing apparatus, only a small amount of the main video can be seen, but the video reproducing apparatus of the present invention can reproduce the entire screen of the main video.

(5) Further, as a sub-picture which prevents display of the main picture, the main picture is displayed only for a certain period of time, in other words, the information of the sub-picture is recorded so as to prevent the display of the main picture only for a certain period of time. Even so, the same effect can be obtained.

(6) In the above embodiment, the sub-picture information (sub-picture display pixel data) is encoded by a specific run-length encoding method. However, the encoding method of the sub-picture display pixel data is as follows. It is not particularly limited, and it is not always necessary to compress the sub-picture display pixel data,
Compression is not necessary if the capacity of the recording medium permits.

(7) Further, as long as the capacity of the recording medium permits, the software provider can freely set the image of the sub-picture. That is, in the above embodiment, as the sub-image that hinders the display of the main image, a sub-image that covers the entire screen of the main image is used, or a part of the screen of the main image is restricted by a lattice-shaped sub-image. This is an example in which the sub-picture reliably prevents the display of the main picture, and any configuration may be used as long as the software provider arbitrarily sets the display of the main picture.

(8) When recording sub-picture information forcibly displayed on the recording medium so as to prevent normal reproduction and display of the main picture, normal reproduction and display of the main picture are prevented except for a certain period of time. Recording, in other words, information of the sub-video may be recorded so that the main video can be normally reproduced and displayed for a certain period of time, for example, at the start of reproduction.

In the case where information of a sub-picture which is forcibly displayed so as to prevent normal reproduction and display of the main picture is recorded on a recording medium, the reproduction and display of the main picture is recorded so as to prevent only a specific part of the main picture. May be.

In this way, by recording the information of the sub-picture forcibly displayed so as to prevent the normal reproduction and display of the main picture, even a user other than the authorized user can confirm the content of the main picture although it is a part. Since it is possible, it can be expected that the user willingly pays a fee and wants to watch.

(9) Canceling the forced display of the sub-picture, which is forcibly displayed so as to prevent normal playback of the main picture, until the number of times of reproduction from the recording medium by the picture reproducing apparatus reaches a predetermined number. Accordingly, the video reproducing apparatus may have a function of reproducing and displaying the main video normally. By doing so, it is possible to restrict the use against the intention of the software provider, such as lending a recording medium based on the present invention and a video reproducing apparatus based on the present invention to a large number of people. From the viewpoint of copyright protection.

(10) In the above embodiment, an optical disk is described as an example of a recording medium. However, basically any recording medium can be used as long as it is a reproduction-only large-capacity recording medium. Also, the specific configuration of the video device may be any configuration as long as the purpose of the present invention is satisfied.

[0075]

As described above, according to the present invention, the information which is forcibly displayed so as to prevent the normal reproduction and display of the main video is recorded on the recording medium as at least a part of the information of the sub video. This makes it possible to prevent normal playback and display of the main video by a user other than the authorized user in the conventional video playback device without the function of canceling the forced display,
It is effective from the viewpoint of copyright protection. Further, since the sub-picture is used to restrict the display of the main picture, the extent to which the software provider prevents normal reproduction and display of the main picture can be freely set.

When the video reproducing apparatus of the present invention is used,
In order to cancel the forced display of the sub-picture which is forcibly displayed so that only the regular user such as the user who paid the predetermined usage fee prevents the normal reproduction display of the main picture from the recording medium on which the recording is performed in this manner. , The main video can be normally reproduced and displayed.

That is, only a legitimate user who has received the key information from the software provider who has received the recording medium from the software provider can correctly reproduce the main video recorded on the recording medium using the video reproducing apparatus according to the present invention. can do.

Further, it goes without saying that the video reproducing apparatus according to the present invention can reproduce from a recording medium recorded in a conventional format without any problem.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a video playback device according to a first embodiment of the present invention.

FIG. 2 is an exemplary view showing a recording format on an optical disc according to the embodiment;

FIG. 3 is an exemplary view showing contents of a display control command group recorded on the optical disc according to the embodiment;

FIG. 4 is a block diagram illustrating a configuration of a video playback device according to a second embodiment of the present invention.

FIG. 5 is an exemplary flowchart illustrating a processing procedure of video reproduction in the embodiment.

FIG. 6 is a block diagram illustrating a configuration of a video playback device according to a third embodiment of the present invention.

FIG. 7 is an exemplary flowchart illustrating a processing procedure of video reproduction in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Recording medium (optical disk) 2 ... Spindle motor 3 ... Optical head 4 ... Motor control circuit 5 ... Reproduction signal processing circuit 6 ... Buffer 7 ... Demultiplexer 8 ... Video buffer 9 ... Sub-picture buffer 10 ... Main control circuit 11 ... Video Decoder 12 ... Sub-picture decoder 13 ... Main / sub-picture mixing circuit 14 ... Video monitor 15 ... Sub-picture display control circuit 16 ... User sub-picture display flag 17 ... Sub-picture forced display release circuit 18 ... Sub-picture forced display release flag 19 ... Sub-picture display release flag generation circuit 20 Password input 21 Random number generation circuit 22 Random number 30 Video stream 31 Video pack 32 Sub-picture pack 33 Audio pack 40 Sub-picture stream 41 Sub-picture header 42 Sub-picture Display pixel data 43 ... Sub-picture display control sequence

Claims (6)

[Claims] 1. A recording medium on which information of a main video as a main moving image and information of other sub-videos is recorded, wherein at least a part of the information of the sub-video prevents normal reproduction and display of the main video. Characterized by recording information forcibly displayed on a recording medium. 2. Information indicating that a sub-picture forcibly displayed so as to prevent normal reproduction and display of the main picture is forcibly displayed, and information indicating that the forcible display based on the information can be canceled is displayed. 2. The recording medium according to claim 1, wherein the recording medium is recorded as control information. 3. The information of a sub-picture forcibly displayed so as to prevent normal reproduction and display of the main video is recorded so as to prevent normal reproduction and display of the main video except for a certain period of time. The recording medium according to claim 1 or 2, wherein 4. The information of a sub-picture forcibly displayed so as to prevent normal reproduction and display of the main picture is recorded so as to prevent reproduction and display of the main picture only for a specific part of the main picture. The recording medium according to claim 1, wherein: 5. A video reproducing apparatus for reproducing a video from a recording medium according to claim 1, wherein said sub-video is forcibly displayed so as to prevent normal reproduction and display of said main video. An image reproducing apparatus, wherein the main image is normally reproduced and displayed by inputting information for canceling the forced display. 6. A video reproducing apparatus for reproducing a video from a recording medium according to claim 1, wherein the number of reproductions from said recording medium by said video reproducing apparatus reaches a predetermined number. A video reproducing apparatus for reproducing and displaying the main video normally by canceling the forcible display of a sub video forcibly displayed so as to prevent normal reproduction and display of the main video.