JP6756890B2 - Digital content receiving device and digital content receiving method - Google Patents

Description

The technical field relates to program receivers. In particular, it relates to copy control technology in equipment.

Regarding the above technical field, Patent Document 1 has an object of "providing a device and a method capable of restricting recording on a recording medium in a recording / reproducing device for digital information to be copyright protected", and as a means for solving the problem, ". When the copy control information is (Copy One Generation), the recording / playback control circuit records the information, the converted digital information obtained by converting the information into a predetermined bit rate, and the copy count information on the recording medium. However, when the digital information or the converted digital information is moved to the recording medium of the recording device connected to the playback device while being (Copy No More) according to the copy control information, the number of possible copies is reduced. A configuration in which the number-of-times information is updated, the digital information signal or the converted digital information, the copy control information, and the copy number-of-times information are recorded again on a recording medium, and the digital information signal or the converted digital information is made unplayable. It was stated. "

Further, Patent Document 2 describes a method of providing a storage recording device that achieves both convenience of a user and protection of the rights of a copyright holder for contents of "copying is possible only for one generation". A diagram is described in which the copyright management information is described and displayed in the program information list to improve the convenience of the user.

Japanese Unexamined Patent Publication No. 2006-114090 Japanese Unexamined Patent Publication No. 2006-244603

In recent years, with the spread of digital broadcasting, various recording media have been distributed, and the forms of viewing digital contents have become diverse. In such an environment, from the viewpoint of copyright protection, it is conceivable to control data transmission / reception between a plurality of recording / playback devices or recording media by using copy control information. However, the control based on the copy control information complicates the determination of whether or not copying is possible between arbitrary devices, and reduces the usability of the user. In the digital information recording / reproducing method shown in Patent Document 1, usability is improved by managing the copyable number of times of digital information whose copy control information is Copy Once Generation and displaying the information of the copyable number of times to the user. doing.

However, the digital information recording / playback device shown in Patent Document 1 only assumes that the copy control information and / or the number of times that the digital data can be copied on the recording medium is displayed to the user, and the recording before recording is performed. There is no description about the user display method in reservation.
Further, in the digital information recording / reproducing device shown in Patent Document 2, only copy generation management information is assumed as copy control information, and a means for displaying the copyable number information to the user is not disclosed.

In these cases, for example, when a plurality of digital data having the same content are broadcast, there is a possibility that inconvenience such as recording the digital data of the one that cannot be copied a plurality of times may occur.

In order to solve the above problems, one embodiment of the present invention uses, for example, the technical idea described in the claims.

According to the above means, for example, a program reservation can be preferably made.

It is a block diagram which shows the configuration example of a system. It is a block diagram which shows the configuration example of the transmission device 1. This is an example of the structure of the content usage descriptor, which is one of the copy control information. It is a description example to each field of the content usage descriptor. This is an example of the structure of the digital copy control descriptor, which is one of the copy control information. This is an example of information that controls the copy generation. This is an example of the reception process in the reception device 3 of each field of the content usage descriptor sent from the transmission device 1. This is an operation example in which the transmission device 1 protects the program content by using the copy control information. This is an example of control when the receiving device 3 stores (records) program contents using copy control information. It is a block diagram which shows the structural example of the recording / reproduction apparatus 10. It is a block diagram which shows the structural example of the recording / reproduction control unit 104. It is a schematic diagram which shows the structural example of the information of the detachable recording medium. It is a schematic diagram which shows the structural example of the information of the detachable recording medium. It is a schematic diagram which shows the screen example which displays the list of the program to be broadcast. It is a schematic diagram which shows the screen example which displays the detailed information of a program. It is a schematic diagram which shows the screen example which displays the setting of a program search. It is a schematic diagram which shows the screen example which displays the result of the program search in a list. It is a schematic diagram which shows the screen example which displays the list of the program to be broadcast. It is a schematic diagram which shows the screen example which displays the detailed information of a program. It is a schematic diagram which shows the screen example which notifies the possibility that copy control information is changed. This is an example of a program content copy control table. It is a block diagram which shows the structural example of the system in 3rd Example. It is a block diagram which shows the structural example of the recording / reproduction apparatus 10 in 4th Example. It is a block diagram which shows the structural example of the recording / reproduction apparatus 10 in 5th Example.

Hereinafter, examples of embodiments suitable for the present invention (Examples) will be described. However, the present invention is not limited to the present embodiment. This embodiment mainly relates to the handling of information that is allowed to be copied for one generation.

This embodiment is one embodiment of the receiving device of the present invention. Hereinafter, this embodiment will be described separately with reference to the screen display processing of the system, the transmitting device, the copy control information, the receiving device, the program guide, the program details, and the program search.
<System>
The system in this embodiment will be described with reference to FIG.
FIG. 1 is a block diagram showing a configuration example of the system in this embodiment. An example shows a case where information is transmitted and received by broadcasting and recorded and reproduced. However, it is not limited to broadcasting and may be VOD (Video On Demand) by communication, and is also collectively referred to as distribution.

1 is a transmitting device installed in an information providing station such as a broadcasting station, 2 is a relay device installed in a relay station or a broadcasting satellite, 3 is a receiving device installed in a user's house, and 10 is a receiving device 3. It is a reception / recording / playback unit built in or external to the unit. The reception / recording / playback unit 10 can record and play back the broadcast information.

The transmission device 1 transmits a modulated signal radio wave via the relay device 2. For example, transmission by cable, transmission by telephone line, transmission by terrestrial broadcasting, etc. can be used. As will be described later, this signal radio wave received by the receiving device 3 is demodulated into an information signal, and then recorded as a signal suitable for recording as needed. If the receiving device 3 has a built-in display, the user can connect the receiving device 3 to a display (not shown) to view the video / audio indicated by the information signal. Can be done.
<Transmission device>
The transmission device in this embodiment will be described with reference to FIG.
FIG. 2 is a block diagram showing a configuration example of the transmission device 1 in the system of FIG. 11 is a source generating unit, 12 is an encoding unit that compresses by an MPEG method or the like, 13 is a scrambling unit, 14 is a modulation unit, 15 is a transmitting antenna, and 16 is a management information adding unit. Information such as video and audio generated by the source generation unit 11 including a camera, a recording / playback device, and the like is compressed by the encoding unit 12 so that it can be transmitted in a smaller occupied band. If necessary, the scramble unit 13 transmits and encrypts the data so that it can be viewed by a specific viewer. After being modulated so as to be a signal suitable for transmission by the modulation unit 14, it is transmitted as a radio wave from the transmission antenna 15 toward the relay device 2. At this time, the management information giving unit 16 adds copy control information, information such as the current time, and information on the program to be broadcast, which are information for controlling copying. The information of the program to be broadcast includes not only the information of the program to be transmitted but also the program information to be transmitted such as the program information for one week.

In many cases, a plurality of pieces of information are multiplexed in one radio wave by a method such as time division or spectrum diffusion. Although not shown in FIG. 2 for the sake of simplicity, in this case, there are a plurality of systems of the source generation unit 11 and the encoding unit 12, and a multiplex that multiplexes a plurality of information between the encoding unit 12 and the scrambling unit 13. A part (multiplexing part) is placed.
<Copy control information>
The copy control information in this embodiment will be described with reference to FIGS. 3 to 9.
The copy control information is information that controls restrictions such as whether or not copying is possible and the number of copies, and is added by, for example, the management information giving unit 16. The copy control information includes a content usage descriptor and a digital copy control descriptor.

FIG. 3 is an example of the structure of the content usage descriptor which is one of the copy control information. The content usage descriptor is generated and added by the management information addition unit 16, for example, and is stored in the MPEG-TS PSI (Progrm Specific Information) (for example, PMT (Program Map Table)) or SI (Service Information) and transmitted. Information to be done. Note that SI also includes program information scheduled to be broadcast, and a program list is created with reference to SI.
The purpose of the content usage descriptor is to arrange (send) when describing control information regarding storage (recording) and output for the program. The meaning is that when the 1-bit field of copy_restriction_mode is "1", even if the digital_recording_control_data of the digital copy control descriptor described in FIG. 5 is "copy is possible only for one generation", it can be recorded as "number limited copy is possible". Indicates that. If it is "0", it cannot be recorded as "limited number of copies allowed".

The content usage descriptor is always placed (transmitted) when the program is subject to output protection. This output protection means that the output protection bit (encryption_mode) of the content usage descriptor is used to protect the high-speed digital interface output of the content that can be copied without restrictions. In other words, it is encrypted when it is output on a digital interface or copied to a recording medium, but there is no limit to the number or generation of copies. Retransmission to the Internet is virtually impossible. Also called "copy-free with output protection" or EPN (encryption plus non-assertion). Further, when the digital copy control information of the program is "copy is possible only for one generation" and is not subject to "copy is possible with a limited number", it is always arranged (transmitted).

FIG. 4 is an example of the description contents of each field of the content usage descriptor on the sending side.
In "descriptor_tag", describe "0xDE" which means content usage descriptor. Describe the descriptor length of the content usage descriptor in "descriptor_length". In "copy_restriction_mode", describe "0" when the digital copy control information is "copy is possible only for one generation" and is not the target of "copy is possible with limited number". If the digital copy control information is "copy is possible only for one generation" and is subject to "copy is possible with a limited number", describe "1". In "encryption_mode", describe "0" when the digital copy control information is "copyable without restrictions" and the high-speed digital interface output is protected. "Retention_mode" means a temporary storage control bit, and describes "0" indicating that temporary storage is possible even if "digital_recording_control_data" (digital copy control information) in the digital copy control descriptor is "copy prohibited". To do. “Retention_state” means a temporary storage allowable time, and describes “111” indicating that storage for 1 hour and 30 minutes is possible. Note that "image_constraint_token", "retention_state", and "encryption_mode" are "1" in the default state. Each field will be described later in FIG. 7 as a process on the receiving side.

FIG. 5 is an example of the structure of the digital copy control descriptor which is one of the copy control information. The digital copy control descriptor is, for example, information that is generated and added by the management information adding unit 16 and stored in the MPEG-TS PSI (for example, PMT) or SI and transmitted.

The digital copy control descriptor represents information for controlling the copy generation by a 2-bit field of "digital_recording_control_data" (digital copy control information).

FIG. 6 is an example of the digital copy control information “digital_recording_control_data”. When the digital copy control information is "00", it indicates that copying is possible without restrictions, when it is "01", it indicates that it is defined by the broadcaster, and when it is "10", only one generation is copied. It indicates that it is possible, and in the case of "11", it indicates that copying is prohibited. Note that copying of only one generation means that the received broadcast signal can be recorded (copy of the first generation), but the broadcast signal cannot be duplicated (copied) after recording.

The content usage descriptors of FIGS. 3 and 4 are also referred to as copy number limit information, and the digital copy control information of FIGS. 5 and 6 is also referred to as copy generation limit information.

A detailed example of the processing of the receiving device 3 related to the copy control information described with reference to FIGS. 3 to 6 transmitted from the transmitting device 1 will be described.

FIG. 7 is an example of processing for each field of the content usage descriptor in the receiving device 3. If "descriptor_tag" is "0xDE", it is determined that the descriptor is a content usage descriptor. Judge that it is the descriptor length of the content usage descriptor by "descriptor_length". If "copy_restriction_mode" is "1" and the digital copy control information is "copy is possible only for one generation", it is determined that the target is "copy is possible with limited number of copies". If it is '0', if the digital copy control information is "copy is possible only for one generation", it is determined that the digital copy control information is not subject to "number-limited copy is possible". Regarding "image_constraint_token", it is judged that the resolution of the video signal output is not limited regardless of any value. Regarding "retention_mode", it is judged that temporary storage is possible regardless of the value. Regarding "retention_state", it is judged that the temporary storage allowable time is 1 hour and 30 minutes regardless of the value. If "encryption_mode" is "1" and the digital copy control information is "copy is possible without restrictions", it is determined that the high-speed digital interface output is not protected. If it is '0', it is determined that the high-speed digital interface output is protected when the digital copy control information is "copy possible without restrictions".

If the content usage descriptor is not placed (sent) for some reason, it may be interpreted that each field has the following values. copy_restriction_mode = ‘1’, image_constraint_token = ‘1’, retention_mode = ‘0’, retention_state = ‘111’, encryption_mode = ‘1’.

FIG. 8 shows an example of an operation relating to the protection of program content by using the copy control information described above. “Operatable” means that the transmitting side can select the content corresponding to each service form as a generation limit using digital copy control information. For example, "pay-per-view" indicates that any digital copy control information may be used, while "monthly pay-per-view" means "copy prohibited" by the sender. Indicates that it cannot be selected. The term "flat / tier" means that a contract for a plurality of channels is collectively called a flat contract for pay broadcasting, and a contract for each channel is called a tier contract. "Other than the above" includes, for example, "in the case of a program not accompanied by content protection, which is not a pay broadcast".

FIG. 9 is an example of control in which the receiving device 3 stores (records) program contents using copy control information.

The content shown in FIG. 9 is, for example, when the program content is stored, if the digital_recording_control_data of the digital copy control descriptor is '10' and "copy is possible only for one generation", the copy control information on the recording medium is "re-recorded". Accumulate as "copy prohibited". However, when copy_restriction_mode is '1', it is accumulated as "Limited number of copies allowed". It should be noted that the value of digital_recording_control_data in the digital copy control descriptor does not need to be changed even when accumulating with "recopy prohibited".

Also, if digital_recording_control_data in the digital copy control descriptor is '10' and "only one generation can be copied", multiple copies must not be generated. However, storage in areas that users cannot access for backup purposes is excluded. Further, the above restriction shall be imposed on each receiving unit of the broadcast, and when there are a plurality of receiving units of the broadcast, the above restriction shall be imposed on each receiving unit of one broadcast.

Regarding the number-limited copy possible, N copies can be generated from the program content accumulated as "number-limited copy possible". The value of N may be, for example, conforming to a standard. When a copy is generated via the high-speed digital interface output, the copy may be performed if the number of copies to be generated can be determined by using the move function or the like. For example, when the interface is IEEE1394 and the output destination can be recognized as a device compatible with the DTCP (Digital Transmission Content Protection) standard. The generated copy shall be in a state of "recopy prohibited" or equivalent.

In addition, when the program content stored as "limited number of copies is possible" is played back and output, the high-speed digital interface processes No More Copies specified in DTCP and outputs the content. The analog video output and digital audio output can be output as "only one generation can be copied".

When the recording medium is a removable recording medium, there is another limitation in addition to FIG. Regarding digital recording of program content on removable recording media, in TV, data service digital recording, or audio service digital recording, the digital_recording_control_data of the digital copy control descriptor is '10' and "only one generation can be copied". When receiving and recording content, three or more copies of the received content are not allowed, even in the first generation (for example, when receiving and recording a broadcast, three or more recording media at the same time are not allowed. Do not record). This value (for example, three or more) may conform to a standard, for example. Also, multiple copies of the same generation with the same recording format are not generated. However, digital recording in areas that the user cannot access for backup purposes is excluded. Further, the recording restriction on the digital recording medium shall be imposed on each receiving unit of the broadcast, and when there are a plurality of receiving units of the broadcast, the above restriction shall be imposed on each receiving unit of one broadcast. If the receiving device is equipped with a recording method that does not support copy_restriction_mode, the copy_control_type of the digital copy control descriptor is '01' and the digital_recording_control_data is '10' regardless of the value of copy_restriction_mode of the content usage descriptor. Digitally record with the treatment of "only one generation can be copied".
<Receiver>
The receiving device in this embodiment will be described with reference to FIGS. 10 to 13.

FIG. 10 is a configuration example of the recording / reproducing device 100 as an example of the recording / reproducing device 10 in the receiving device 3. The recording / playback device may be a device having only one of recording and playback functions.

Reference numeral 101 denotes an input terminal, which receives digital data such as radio waves from the relay device 2. Reference numeral 102 denotes a receiving unit, which performs frequency conversion, modulation operation, error correction, and the like on the digital data received from the input terminal 101, and separates the bitstream in one multiplexed transponder into packets such as video and audio. Reference numeral 103 denotes a video / audio information processing unit, which decodes video data and audio data. Reference numeral 104 denotes a recording / reproduction control unit that controls recording or reproduction on a recording medium, and FIG. 11 shows an example of a more detailed internal configuration of this module. Reference numeral 105 denotes a recording medium for recording digital data such as a hard disk drive. Reference numeral 106 denotes a display control unit that generates output data from video / audio data and display data of various application interfaces (IF). For example, the video data processed by the video / audio processing unit 103 is scaled as necessary, and the video data is superposed with image data independently prepared by the recording / playback device 100, such as an operation interface or a still image. Generate an image. Reference numeral 107 denotes an output terminal, which transfers the generated data to a display device (display unit) such as a display liquid crystal panel. Reference numeral 108 denotes a remote control IF when the user performs an operation using the remote control. Reference numeral 109 denotes an input terminal, which is a light receiving unit that receives a signal from the remote controller. Reference numeral 110 denotes an operation unit for arranging a group of buttons for performing operations such as recording and playback, and controlling the recording / playback device 100 by the user directly operating the buttons. Reference numeral 111 denotes a control unit that controls the operation of the recording / reproducing device 100, and is composed of, for example, a CPU. Reference numeral 112 denotes a non-volatile memory for recording information. Reference numeral 113 denotes a system bus that performs data communication between each block connected to the control unit 111.

Reference numeral 114 denotes a slot (also referred to as a detachable portion) to which a detachable recording medium can be attached. Reference numeral 115 denotes a removable recording medium that records in the same recording format as the recording medium 105. Reference numeral 116 denotes a switch, which selects which data of the recording medium 105 or the detachable recording medium 115 is output or which data is input to the recording / reproduction control unit 104. Although only one switch is shown in FIG. 10, it is conceivable to prepare different switches for input and output. Alternatively, a configuration is conceivable in which a recording / reproduction control unit is prepared for each of the recording medium 105 and the detachable recording medium 115.

FIG. 11 is a configuration example of the recording / playback control unit 104.
Reference numeral 201 denotes an input / output terminal, which is connected to the system bus 113 to transmit a control signal. Reference numeral 202 denotes an input terminal, which inputs digital data including video data and audio data to be recorded on a recording medium. Reference numeral 203 denotes a copy control information processing unit, which analyzes the copy control information included in the digital data and updates it as necessary. Reference numeral 204 denotes an encryption unit, which encrypts the input digital data by using, for example, the key information transmitted by the control unit 111. Reference numeral 205 denotes a recording control unit, which issues a command for recording on a recording medium and performs processing such as transfer of digital data. Reference numeral 206 denotes an output terminal, which is connected to a recording medium. Reference numeral 207 is an input terminal for inputting digital data to be reproduced from the recording medium. Reference numeral 208 denotes a reproduction control unit, which issues a command to the recording medium to reproduce desired digital data. Reference numeral 209 denotes a decoding unit, which decrypts the read encrypted digital data by using, for example, the key information transmitted from the control unit 111. Reference numeral 210 denotes an output terminal, which outputs the decoded digital data. Reference numeral 211 denotes a system bus, which is a system bus that performs data communication between each block connected to the control unit.

When storing digital data in the recording medium 105, the control unit 111 controls, for example, based on the digital copy control descriptor and the content utilization descriptor included in the digital data. The digital copy control descriptor is represented by, for example, a copy control type and digital recording control data, and the content utilization descriptor is represented by a signal consisting of, for example, an encryption mode and a digital recording control mode. The control unit 111 instructs the copy control information processing unit 203 to update the copy control information of the digital data stored in the copy control information processing unit 203 according to the values of these descriptors, and instructs the encryption unit 204 to encrypt / not encrypt the digital data.

The copy control information processed by the copy control information processing unit 203 includes, for example, copy generation management information and copyable quantity information, and the copy generation management information is, for example, a 2-bit signal as shown below. 11 Copy-never )
01 Cannot be recopied after recording (No-more-copies)
10 Only one generation can be recorded (Copy-one-generation)
00 Copyable (Copy-free)
It is possible to specify such as. It is conceivable to specify the number of copyable pieces as an integer of 0 or more and specify how many pieces can be copied. Further, digital data whose copy generation management information is "copyable" may include data that is encrypted and output-protected and data that is not encrypted and output-protected.

FIG. 12 is an example of a preferable data structure of the removable recording medium 115 (for example, a removable hard disk). 301 is a management area that cannot be accessed by the user. Confidentiality is maintained by storing the key data for encrypting the digital data and recording it in the data recording area 302 in the management area. Reference numeral 302 denotes a data recording area in which the user can access the internal data by a predetermined operation. Key data is recorded in 301. In 302, information reproduction data for determining key information corresponding to each data in the data recording area is recorded together with data such as video / audio data and still image data. Copy control information can be collectively recorded in the management area 301 on such a detachable recording medium 115.

FIG. 13 shows an example of a preferable data structure of the recording medium of FIG. 12 in another expression. This recording medium is a recording medium (also called a security removable medium) capable of copy control. The copy control here includes management of multiple copies (also referred to as copy number management, copy number control, number control copy) and / or copy generation management (also referred to as copy generation management, copy generation control, generation control copy). )including. One recording medium has a normal area that can be accessed by the user and an anti-tamper area that cannot be accessed by the user. Confidential information stored in the anti-tamper area can be accessed if authentication can be confirmed by authentication processing with a device that can handle this recording medium, so that confidential information can be managed. It has become. The management area 301 in FIG. 12 corresponds to the anti-tamper area, and the data recording area 302 corresponds to the normal area.

In the recording / playback device 100 shown in FIG. 10, the detachable recording medium 115 is different from the one shown in FIGS. 12 and 13, and for example, management information and program information related to copy control may be tampered with illegally. If it is a certain recording medium or a recording medium that cannot be copied (a recording medium that is not certified by standards as supporting copy control), input to this recording medium 115 (non-secure recording medium). When recording the digital data input from the terminal 101, the control unit 111 causes the copy control information processing unit 203 to record the copy generation management information as No-more-copies and the copyable number information as 0.
<Screen display processing of program guide, program details, and program search>
The program guide, program details, and screen display processing of the program search of the receiving device in this embodiment will be described with reference to FIGS. 14 to 20.

In this embodiment, a case where the user uses a remote controller or uses the operation unit 110 (the receiver unit and the operation unit 110 of the remote controller are also collectively referred to as an operation input unit) to make a recording reservation to the recording / playback device 100. Think. It is assumed that the digital data input from the input terminal 101 is, for example, a digital broadcast signal. When recording a digital broadcast, it is effective to make a recording reservation using an electronic program guide created based on SI information sent from a broadcasting station in order to improve user convenience, and it is generally effective. Recording reservations are often made using electronic program guides.

When copy control information is added to the program content, as described in <copy control information>, the content must be protected and recorded and stored when the program content is recorded and stored. If the content usage descriptor and the digital copy control descriptor are inserted in the SI information, the copy generation management information and the copyable quantity information of the program reserved at the time of reservation can be grasped, so that the recording destination can be set to the corresponding storage medium. , You can select and reserve the program that can be copied multiple times, but if the SI information does not have the content usage descriptor or digital copy control descriptor, the copy generation management information or copy of the program reserved at the time of reservation is possible. The number information cannot be grasped.

Hereinafter, an example of a process for creating an electronic program guide when the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to the copy_restriction_mode information is not included in the SI information will be described.

If the copy control method to be used is uniquely determined for each broadcasting network, for example, if all terrestrial digital broadcasting is "only one generation can be copied" and "multiple copies are possible", all terrestrial digital broadcasting programs are "one". Displayed in the electronic program guide as "Multiple copies are possible" with "Only generations can be copied". The following is an example of the copy control method used for each broadcasting network.
Digital terrestrial broadcasting: "Only one generation can be copied" and "Multiple copies are possible"
BS free broadcast: "Only one generation can be copied" and "Multiple copies are possible"
CS free broadcast: "Only one generation can be copied" and "Multiple copies are possible"
BS pay broadcasting: "Only one generation can be copied" (Copy-one-generation)
CS pay broadcasting: "Only one generation can be copied" (Copy-one-generation)
Hereinafter, the details of the electronic program guide creation process in the receiver 3 will be described.
The digital data input to the input terminal 101 is separated into video / audio data, SI information, and the like by the receiving unit 102. Based on the SI information (for example, EIT) separated by the receiving unit 102, the control unit 111 creates an electronic program guide to be displayed on the screen. At this time, the copy generation management information and the copyable number information (hereinafter collectively referred to as copy control information) are included in the electronic program guide for each of the above broadcast networks.

FIG. 14 is an example of an electronic program guide including copy control information. 1401 is a date field representing a date, and 1402 is a time field representing a time. The example of FIG. 14 is an example of displaying a list of programs from 5:00 PM to 7:00 PM on the 19th in BS free broadcasting. Reference numeral 1403 is a scheduled broadcast program column for displaying scheduled broadcast programs of each broadcasting station, and is separated by a scheduled broadcast time. Reference numeral 1404 is a program detailed information column for displaying program detailed information such as a program channel, broadcast date and time, program name, and copy control information selected by the user by the remote controller or the operation unit 110. In the example of FIG. 14, in the copy control information of the program detailed information column 1404, the copy generation information and the copyable number information are displayed as character strings. However, the display method may be a character string or an image such as an icon (the same applies to FIGS. 15 and later). Further, the copy control information may be only the copy generation information or only the copyable quantity information, but it is preferable to display the copyable quantity information (the same applies to FIGS. 15 and later).

In the example of FIG. 14, the copy control information is displayed in the program detailed information column 1404, but the copy control information may be displayed in each program delimiter in the broadcast scheduled program column 1403. As a result, the copy control information can be identified even if the program detailed information column 1404 is not included in the program list.

Further, in the case of the recording / playback device 100 that allows the removable recording medium 115 having no management area inaccessible to the user, that is, in the case of the recording / playback device 100 that records on a medium that does not support copyright management, FIG. As shown in, the copy control information in the case of "recording on a copyright management compatible medium" and the copy control information in the case of "recording on a non-copyright management compatible medium" are displayed in the program detailed information column 1404. As a result, it is possible to improve the convenience of the user even for a recording / playback device capable of recording on a medium that does not support copyright management.

In the example of FIG. 18, the copy control information is displayed in the program detailed information column 1404, but the copy control information may be displayed in each program delimiter in the broadcast scheduled program column 1403. As a result, the copy control information can be identified even if the program detailed information column 1404 is not included in the program list.

FIG. 15 is an example of a program detailed information screen when the user uses the remote controller or uses the operation unit 110 to display the detailed information of the program. An example of the process of creating the program detailed information screen when the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it is not included in the SI information is shown.

The digital data input to the input terminal 101 is separated into video / audio data, SI information, and the like by the receiving unit 102. Based on the SI information separated by the receiving unit 102, the control unit 111 displays the program details screen on the screen. At this time, the copy control information of the copy generation management information and the copyable number information is included in the program details screen for each of the broadcast networks. In the example of FIG. 15, it is an example of the program detail screen of the BS free broadcast program, and the copy control information is displayed as an icon, but the display method may be a character string or an image other than the icon. You may.

In the case of the recording / reproducing device 100 that allows the detachable recording medium 115 having no management area inaccessible to the user (that is, in the case of the recording / reproducing device 100 that records on a medium that does not support copyright management), FIG. As shown in, the copy control information in the case of "recording on a media compatible with copyright management" and the copy control information in the case of "recording on a medium not compatible with copyright management" are displayed. In the example of FIG. 19, it is displayed as an icon, and in the case of "recording on a media compatible with copyright management", up to 9 copies can be made, and in the case of "recording on a medium not supporting copyright management", up to 9 copies can be made. Indicates that copying is not possible. As a result, it is possible to improve the convenience of the user even for a recording / playback device capable of recording on a medium that does not support copyright management.

FIG. 16 is an example of a program search screen when a user searches for a program from a program scheduled to be broadcast by using the remote controller or using the operation unit 110. Reference numeral 1601 is various setting fields for setting various settings in the program search. In this embodiment, copy control information setting items are provided in various setting fields so that copy control information can be set as a search target. In the copy control information setting of FIG. 16, "copy free", "(one generation) multiple copies are possible", and "no copy control" can be checked with the check buttons, and the search is performed with the items checked by the user. For example, when "(1 generation) multiple copies are possible" is checked and searched, only the programs of "(1 generation) multiple copies are possible" are displayed as the search result. Of course, you can also search by keyword and search by genre at the same time. A plurality of copy control information settings can be set at the same time, and all of them can be unchecked.

When performing a search, copy control used for each broadcasting network when the SI information does not include copy_restriction_mode information in the content usage descriptor or information related to copy control that corresponds to it one-to-one for the checked item. When the method is uniquely determined, all the broadcast programs of the broadcast network are searched as the programs of the copy control information.

FIG. 17 is an example of a program search result display screen when a program is searched from a program scheduled to be broadcast. The search results for the copy control information set in the copy control information setting item of FIG. 16 are displayed in a list. Reference numeral 1701 is a search result list display field, which is displayed including copy control information for the program. The display method may be a character string or an image such as an icon. Further, the copy control information may be only the copy generation information or only the copyable quantity information, but it is preferable to display the copyable quantity information.

If the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it one-to-one, and the copy control method to be used is uniquely determined for each broadcasting network, it is used for each broadcasting network. It is also possible to protect the copyright by managing the copy control method of the above as a table and storing the table in an anti-tamper area that cannot be accessed by the user.

In addition, if the future operation is uncertain, such as when the BS pay broadcasting and CS pay broadcasting are currently copy-one-generation, but in the future it will be possible to copy only one generation and multiple copies are possible. When a user makes a recording reservation for a program on the broadcast network, a message indicating that the program may be changed in the future may be displayed as shown in FIG. As a result, even if there is a possibility of change in the future, the user can recognize it in advance, and the convenience of the user can be improved.

Next, consider a case where a program has already been recorded as a method of displaying the copyable number information among the copy control information of the above embodiment. It is assumed that a program having the same content as the program to be broadcast is recorded on the recording medium 105 or the removable recording medium 115 inserted in the slot 114. Here, the programs having equivalent contents include, for example, a program recorded by different devices and broadcast on the same date and time, a program broadcast and a program rebroadcast. Whether or not the program is equivalent is determined, for example, by determining the program title, program number, channel, broadcast date and time, broadcast area, etc. as program identification information. The length (time) of the program, the analysis result of the content of the program (video / audio data), and the like may be added to the judgment factors of whether or not they are equivalent. The fact that the contents are equivalent in this way is also expressed as the contents of the programs being duplicated. The detection does not require that this information is exactly the same in order to judge whether it is equivalent or not, and it is equivalent (or not) if at least a part (for example, the title) is matched. You just have to make a judgment.

A program whose content is equivalent to the program scheduled to be broadcast is recorded, copy control information is added to the program whose content is equivalent to the program scheduled to be broadcast, and copyable quantity information is added to both. In this case, the total number of copies of the program scheduled to be broadcast and the number of copies of the program whose recorded contents are equivalent is displayed as the number of copies of the program scheduled to be broadcast such as a program list. For example, when the copyable number of recorded programs is 6 and the copyable number of programs scheduled to be broadcast is 9, the copyable number of programs scheduled to be broadcast such as a program list is displayed as 15. If the copy control information is not added to the program scheduled to be broadcast, the copy information is added to the program scheduled to be broadcast and displayed even if the copy control information is added to the program whose recorded contents are equivalent. However, when making a recording reservation, a message stating "A program with restricted copying is being recorded. Do you want to replace it?" Is displayed so that the user can select it. As a result, the user can also know the information of the program whose recorded contents are equivalent, and the convenience of the user can be improved.

In this embodiment, the processing when the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it in the first embodiment is performed based on another criterion. Is. The system, the transmitting device, the copy control information, and the receiving device in this embodiment are the same as those in the first embodiment.

The screen display processing of the program guide, the program details, and the program search in the second embodiment of the present invention will be described below.

Most of the program guide, program details, and program search screen display processing in this embodiment are the same as in the first embodiment. This is the case when the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it one-to-one, and the copy control method to be used in the broadcast time zone for each channel is uniquely determined.

If the copy control method to be used is uniquely determined for each channel's broadcast time zone, for example, all 8ch weekdays of terrestrial digital broadcasting from 8:00 to 10:00 are "copyable for only one generation" and "multiple copies are possible". In this case, all 8ch weekdays of terrestrial digital broadcasting from 8:00 to 10:00 are displayed in the electronic program guide as "only one generation can be copied" and "multiple copies can be made". Here, it is all on weekdays, but it may be changed for each day of the week. In addition, if the future operation is uncertain, such as when the copy-one-generation time zone or in the future it will be "copyable only for simultaneous generation" and "multiple copies are possible", the program in the relevant time zone of the relevant channel When the user makes a recording reservation, a message indicating that the program may be changed in the future may be displayed as shown in FIG. As a result, even if there is a possibility of change in the future, the user can recognize it in advance, and the convenience of the user can be improved.

Further, the copy control method may be uniquely determined for each program instead of the broadcast time zone for each channel. For example, when it is decided that a serial drama or news program will be broadcast weekly or daily, the receiver knows the broadcast time zone of the program, so the SI information includes copy_restriction_mode information of the content usage descriptor, or a pair with it. Even when the information related to the copy control corresponding to one is not included, the copy control information of the program can be displayed in the electronic program guide, and the user can make a recording reservation based on the information.

For the screen display of the program details and the program search, the same processing as the copy control information determination processing shown in the display processing of the electronic program guide may be used, and the other processing is the same as that of the first embodiment. ..

In this embodiment, the processing when the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it in the first embodiment is performed based on another criterion. Is. The system, the transmitting device, the copy control information, and the receiving device in this embodiment are the same as those in the first embodiment.

The screen display processing of the program guide, the program details, and the program search in the third embodiment of the present invention will be described below.

Most of the program guide, program details, and program search screen display processing in this embodiment are the same as in the first embodiment.

Prepare a program content copy control table that lists the program content currently being broadcast and will be broadcast on the transmitting side such as a broadcasting station, copy_restriction_mode information of the content usage descriptor for the program content, or information related to copy control that corresponds one-to-one with it. To do. FIG. 21 shows an example of the program content copy control table. In FIG. 21, the content ID that uniquely identifies the program content (for example, the event_id of MPEG-2 TS) and the program name are listed, but only the content ID that uniquely identifies the program content may be used. Further, in FIG. 21, only digital_recording_control_data of the digital copy control descriptor and copy_restriction_mode of the content usage descriptor are described as copy control information, but the entire digital copy control descriptor and the entire content usage descriptor may be described, respectively. ..

The broadcasting station creates the program content copy control table containing the program content copy control information for a certain period of time, and uses a multiplex unit (multiplex unit) (not shown in FIG. 2) to display the program content copy control table on the broadcast wave. It is multiplexed and transmitted from the transmitting antenna 15.
The processing in the receiving device 100 will be described below.

The digital data input to the input terminal 101 is separated by the receiving unit 102 into video / audio data, SI information, and a program content copy control table multiplexed on the broadcast wave on the transmitting side. Based on the SI information (for example, EIT) separated by the receiving unit 102, the control unit 111 displays the electronic program guide on the screen. At this time, copy control information (copy generation management information and copyable number) of the content ID that uniquely identifies the program content in the program content copy control table that matches the content ID that uniquely identifies the program content included in the SI information. Information) is included in the electronic program guide. It should be noted that the judgment may be made based on the program name or the like instead of the content ID.

As a result, even if the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it one-to-one, the copy control information for each program can be grasped, and the copy control information can be electronically stored. It can be displayed in a program guide, and the user can select a program to be reserved for recording based on the copy control information, which can improve the convenience of the user.

For the screen display of the program details and the program search, the same processing as the copy control information determination processing shown in the display processing of the electronic program guide may be used, and the other processing is the same as that of the first embodiment. ..

In this embodiment, the network is used as the transmission / reception means of the program content copy control table in the third embodiment.
Hereinafter, the differences from the third embodiment will be described.
<System>
The system in this embodiment will be described with reference to FIG.
FIG. 22 is a block diagram showing a configuration example of the system in this embodiment, in which a server connected to the network is added to the block diagram of FIG.

Reference numeral 4 denotes a server installed in an information providing station such as a broadcasting station or a service provider, and is connected to a network such as the Internet.

The server 4 is a program content copy control that lists the copy_restriction_mode information of the program content currently being broadcast and to be broadcast and the content usage descriptor for the program content shown in FIG. 21, or the information related to the copy control corresponding to the copy_restriction_mode information. Save the table. If there is a connection request and a program content copy control table request from the receiver side, the program content copy control table is transmitted via the network in response to the request. When a request is received, it may be transmitted after performing authentication such as device authentication. In this case, more secure communication can be performed. In addition, requests from other than the service provider can be rejected, and the service supply range can be limited.
The system in this embodiment is the same as that in the third embodiment except for the above.
<Transmission device>
The transmission device in this embodiment is the same as that in the third embodiment.
<Copy control information>
The copy control information in this embodiment is the same as that in the third embodiment.
<Receiver>
The receiving device in this embodiment is the same as that in the third embodiment, but may have a configuration as shown in FIG. 23.

FIG. 23 is substantially the same as the recording / reproducing device shown in FIG. 10, and the input of copy control information to the recording / reproducing control unit 104 is different. Reference numeral 141 denotes a network transmission / reception terminal, which transmits / receives data via a network such as the Internet. Reference numeral 142 denotes a network transmission / reception unit, which analyzes data transmitted / received at the network transmission / reception terminal and performs protocol processing. The 142 is controlled by the control unit 111 connected by the system bus, and when transmitting data, it is transmitted from the network transmission / reception terminal 141, and the data received from the network transmission / reception terminal 141 is protocol-processed and then copied to the recording control unit 104. Enter.
<Screen display processing of program guide, program details, and program search>
Most of the program guide, program details, and program search screen display processing of the receiving device in this embodiment are the same as those in the third embodiment. Hereinafter, a portion different from that of the third embodiment will be described.

In the third embodiment, the program content copy control table shown in FIG. 21 is multiplexed and transmitted over the broadcast wave, but in the present embodiment, the program content copy control table is transmitted via the network. Specifically, a program that lists the program content currently being broadcast or will be broadcast on the transmitting side such as a broadcasting station, copy_restriction_mode information of the content usage descriptor for the program content, or information related to copy control corresponding to it one-to-one. A content copy control table is prepared on the server 4 so that it can be transmitted via the network at any time. On the receiver side, the same processing as in the third embodiment is performed for the broadcast wave. Further, the request instruction of the program content copy control table is requested to the server 4 via the network, and if necessary, the server side performs authentication processing such as device authentication to acquire the program content copy control table. When the user uses the remote controller or the operation unit 110 to display the electronic program guide, SI information is acquired from the broadcast wave, and the control unit 111 displays the electronic program guide on the screen based on the SI information. indicate. At this time, copy control information (copy generation management information and copyable) of the content ID that uniquely identifies the program content of the program content copy control table that matches the content ID that uniquely identifies the program content included in the SI information. Include (quantity information) in the electronic program guide. It should be noted that the judgment may be made based on the program name or the like instead of the content ID.

As a result, even if the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it one-to-one, the copy control information for each program is not duplicated in the broadcast wave. Can be grasped, copy control information can be displayed in an electronic program guide, the user can select a program to be reserved for recording based on the copy control information, and the convenience of the user can be improved.

For the screen display of the program details and the program search, the same processing as the copy control information determination processing shown in the display processing of the electronic program guide may be used, and the other processing is the same as that of the third embodiment. ..

In this embodiment, in the first embodiment, the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to the copy_restriction_mode information, and the PSI information includes the processing. It is implemented according to different criteria. The system, transmission device, and copy control information in this embodiment are the same as those in the first embodiment.

The screen display process of the receiving device, the program guide, the program details, and the program search in the third embodiment of the present invention will be described below.

The receiving device in this embodiment is substantially the same as that in the first embodiment, but includes a plurality of input terminals 101 and a plurality of receiving units 102 in FIG. Here, for the sake of simplicity, it is assumed that there are two input terminals and two receiving units, and FIG. 24 shows a configuration example of the recording / reproducing device 150 having two input terminals and two receiving units with respect to FIG.

Reference numeral 151 denotes an input terminal, which has the same function as the input terminal 101. Reference numeral 152 is a receiving unit, which has the same function as the receiving unit 102. That is, the digital data received from the input terminal 101 or the input terminal 151 is subjected to frequency conversion, modulation operation, error correction, and the like, and the bitstream in one multiplexed transponder is separated into packets such as video and audio. The video / audio separated by the receiving unit 102 or the receiving unit 152 is processed by the video / audio information processing unit 103. Similarly, the copy control information separated by the receiving unit 102 or the receiving unit 152 is processed by the recording / reproducing control unit 104. The content of the process is the same as that of the first embodiment.

Next, the program guide, program details, and screen display processing for program search will be described.
Most of the program guide, program details, and program search screen display processing in this embodiment are the same as in the first embodiment.

After processing the data received by the input unit 101 of the recording / playback device 150, which is the receiving device, by the receiving unit 102 and the video / audio information processing unit 103, the display control unit 106 outputs the video / audio via the output terminal 107. .. At this time, the input terminal 151 and the receiving unit 152, which do not output video / audio, circulate and receive the broadcast waves of all the channels being broadcast. That is, a content ID (for example, MPEG-2 TS event_id) that receives the broadcast wave of a certain channel at the input terminal 151 and uniquely identifies the copy control information and the program content included in the PSI information of the program at the receiving unit 152. To get. A program content copy control table listing the acquired content IDs and copy control information is created and recorded on the recording medium 105 or the removable recording medium 115. The program content copy control table is the same as that shown in FIG. 21, and the program name may be included in the list, or only the program name may be used instead of the content ID. It is desirable that the program content copy control table be recorded in the tamper-resistant region of the recording medium 105 and the removable recording medium 115. After adding the copy control information of the program to the program content copy control table, the channel is selected for another channel, and the same processing is performed to add the copy control information of the program to the program content copy control table.

Next, a process when the user uses the remote controller or uses the operation unit 110 to display the electronic program guide will be described. The digital data input to the input terminal 101 is separated into video / audio data, SI information, etc. by the receiving unit 102. Based on the SI information (for example, EIT) separated by the receiving unit 102, the control unit 111 displays the electronic program guide on the screen. At this time, if the program content copy control table recorded on the recording medium 105 or the detachable recording medium 115 includes the copy control information of the content ID, the copy control information (copy generation management information and copyable number information) ) Is included in the electronic program guide. It should be noted that the judgment may be made based on the program name or the like instead of the content ID.

As a result, even if the SI information does not include copy_restriction_mode information of the content usage descriptor or information related to copy control corresponding to it one-to-one, programs that are broadcast regularly such as weekly or daily (for example, news programs and serial dramas). Etc.) Or, it is possible to grasp copy control information such as a program that has been broadcast once in the past. In addition, it is not necessary to create a program content copy control table on the transmitting side, and it is not necessary to install a special device on the transmitting side.

As a result, the copy control information can be displayed in the electronic program guide, the user can select a program to be reserved for recording based on the copy control information, and the convenience of the user can be improved.

For the screen display of the program details and the program search, the same processing as the copy control information determination processing shown in the display processing of the electronic program guide may be used, and the other processing is the same as that of the first embodiment. ..

This embodiment is an embodiment in which the program content copy control table acquired by each means in Examples 3 to 5 is used for recording / playback control in another recording / playback device. The system, the transmitting device, the copy control information, and the receiving device in this embodiment are the same as those in the third, fourth, and fifth embodiments.

The screen display processing of the program guide, the program details, and the program search in the sixth embodiment of the present invention will be described below.

Most of the screen display processing of the program guide, program details, and program search in this embodiment is the same as the processing in each embodiment.

First, the program content copy control table acquired in each embodiment is stored in the detachable recording medium 115. It is desirable that the program content copy control table be stored in the tamper-resistant area of the removable recording medium 115.

The detachable recording medium 115 storing the program content copy control table is attached to the slot 114 of the recording / reproducing device which is the receiving device in this embodiment. The recording / reproducing device in this embodiment is the same as that shown in FIG.

The digital data input to the input terminal 101 is separated into video / audio data, SI information, etc. by the receiving unit 102. Based on the SI information (for example, EIT) separated by the receiving unit 102, the control unit 111 displays the electronic program guide on the screen. At this time, if the program content copy control table recorded on the detachable recording medium 115 includes the copy control information of the content ID, the copy control information (copy generation management information and copyable number information) is electronically programmed. Include in the table. It should be noted that the judgment may be made based on the program name or the like instead of the content ID.

As a result, when the SI information does not include the copy_restriction_mode information of the content usage descriptor or the information related to the copy control corresponding to it one-to-one, the recording / playback device processes the program content copy control table multiplexed on the broadcast wave. If there is no function (Example 3), or if the recording / playback device does not have a function to process the program content copy control table via the network (Example 4), or if the recording / playback device does not have a function (Example 4), or the program content is used by using a plurality of input terminals and receivers. Even if there is no function for generating and processing the copy control table (Example 5), the copy control information for each program can be grasped.
As a result, the copy control information can be displayed in the electronic program guide, the user can select a program to be reserved for recording based on the copy control information, and the convenience of the user can be improved.

For the screen display of the program details and the program search, the same processing as the copy control information determination processing shown in the display processing of the electronic program guide may be used, and the other processing is the same as that of the first embodiment. ..

1 ... Transmitter 2 ... Relay device 3 ... Receiver 11 ... Source generator 12 ... Encoding section 13 ... Scramble section 14 ... Modulation section 15 ... Transmitting antenna 16・ ・ ・ Management information addition unit 10, 100 ・ ・ ・ Recording / playback device 101, 109, 201, 202, 207 ・ ・ ・ Input terminal 102 ・ ・ ・ Reception unit 103 ・ ・ ・ Image / audio signal processing unit 104 ・ ・ ・Recording / playback control unit 105 ... Recording medium 106 ... Display unit 107, 206, 210, 1203, 1302 ... Output terminal 108 ... Remote control interface 110 ... Operation unit 111 ... Control unit 112 ...・ ・ Non-volatile memory 113 ・ ・ ・ System bus 203 ・ ・ ・ Copy control Information processing unit 204 ・ ・ ・ Encryption unit 205 ・ ・ ・ Recording control unit 208 ・ ・ ・ Playback control unit 209 ・ ・ ・ Decryption unit 114 ・ ・ ・Slot 115: Detachable recording medium 116: Switch

Claims (2)

In a digital content receiving device that receives transmitted digital content,
The digital content includes
The first copy control information used when reserving the recording of the digital content and
A second copy control information that is information used when recording the digital content and has a state indicating that at least one generation of the digital content can be copied.
The copy control mode information indicating whether or not the digital content received when the second copy control information can be copied for one generation is the content that can be copied in a limited number can be attached.
A receiver that receives the transmitted digital content and
The first recording medium, which is a recording medium corresponding to the recording of the digital content based on the copy control mode information, and
A reservation unit that makes a reservation for recording the digital content on the first recording medium, and
A recording unit that records the received digital content on the first recording medium, and
A control unit that controls the reservation unit, the reception unit, and the recording unit is provided.
The control state in the control unit includes
A first state in which a reservation for recording the digital content on the first recording medium is made using the first copy control information, and a first state.
The digital content received when the second copy control information can be copied for one generation and the copy control mode information indicates that the received digital content is content that can be copied in a limited number. In a second state in which the information is recorded on the first recording medium and the number of digital copies that can be generated from the recorded digital content is managed so as to be within a predetermined number.
When the second copy control information can be copied for one generation and the copy control mode information is not associated with the received digital content, the received digital content is recorded on the first recording medium. A third state in which the number of digital copies that can be generated from the recorded digital content is managed so as to be within the predetermined number, and
A digital content receiver characterized by having. In the digital content receiving method for receiving the transmitted digital content,
The digital content includes
The first copy control information used when reserving the recording of the digital content and
A second copy control information that is information used when recording the digital content and has a state indicating that at least one generation of the digital content can be copied.
The copy control mode information indicating whether or not the digital content received when the second copy control information can be copied for one generation is the content that can be copied in a limited number can be attached.
A reservation step for making a reservation for recording the digital content on a first recording medium corresponding to the recording of the digital content based on the copy control mode information, and
A receiving step for receiving the transmitted digital content, and
It has a recording step of recording the received digital content on the first recording medium.
In the reservation step,
There is a first state in which a reservation is made for recording the digital content on the first recording medium using the first copy control information.
In the recording step,
The digital content received when the second copy control information can be copied for one generation and the copy control mode information indicates that the received digital content is content that can be copied in a limited number. In a second state in which the information is recorded on the first recording medium and the number of digital copies that can be generated from the recorded digital content is managed so as to be within a predetermined number.
When the second copy control information can be copied for one generation and the copy control mode information is not associated with the received digital content, the received digital content is recorded on the first recording medium. A third state in which the number of digital copies that can be generated from the recorded digital content is managed so as to be within the predetermined number, and
A digital content receiving method characterized by having.

Images