JP2002204406A - Digital broadcast receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast receiver that can prevent video contents whose copy is inhibited from being analogically copied, even when a received digital broadcast signal has any format. SOLUTION: A control section 13 discriminates whether or not copying of the received digital broadcast signal is inhibited according to copy inhibit information. The control section 13 controls a format conversion section 9 to forcibly convert the digital broadcast signal into a signal with the standard format of the 480I or 480P independently of the format of the digital broadcast signal. The control section 11 controls a D/A video output processing section 11 to attach a copy protection signal to the broadcast signal in matching with the control above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital broadcast receiver capable of preventing analog copying of copy-protected video contents.

[0002]

2. Description of the Related Art In recent years, digitalization of television broadcasting has been rapidly progressing. In Japan, digital broadcasting using a broadcasting satellite (BS) was started in December 2000. In digital broadcasting, many pay broadcast channels are also distributed. In the case of pay broadcasting, it is necessary to prohibit recording (copying) of video contents by a video tape recorder (VTR) or the like. Therefore, the digital broadcast receiver has a function of inserting and outputting a copy protection signal for a copy-prohibited broadcast such as a pay broadcast.

FIG. 6 is a block diagram showing a general configuration of a digital broadcast receiver. Here, the received digital broadcast signal is an interlace (480I) of 480 scanning lines.
Or 480 scanning lines progressive (480P)
Is a standard format (SD format)
The operation in the case of is described. In FIG. 6, a digital broadcast signal from a BS is received by a BS antenna (not shown), and a BS-IF signal output from the BS antenna is:
The signal is input to the front end unit 2 via the BS-IF input terminal 1. The front end unit 2 selects an arbitrary frequency according to a channel selection instruction signal from the control unit 13, performs I / Q detection, and outputs an I-axis and Q-axis baseband signal.

[0004] NIM (Network Interface
The module) unit 3 receives the I-axis and Q-axis baseband signals from the front end unit 2 and
Performs PSK demodulation, error correction, TS (transport stream) selection, and the like under the control of the control unit 13.
Play and output a predetermined transport stream. This transport stream is input to the demultiplex unit 4. The demultiplex unit 4 decodes the data and performs a process of sorting audio data and video data. The demultiplex unit 4 also extracts copy prohibition information described later.

[0005] The audio data output from the demultiplex unit 4 is input to an audio decoding unit 5, where the audio data is decoded, and analog-converted by a D / A audio output processing unit 6. The analog audio signal output from the D / A audio output processing unit 6 is output from an analog audio output terminal 7.

On the other hand, the video data output from the demultiplex unit 4 is input to an MPEG-video decoding unit 8 and subjected to MPEG2 decoding processing. MPE
The output of the G-video decoding unit 8 is the format conversion unit 9
And converted into a video format suitable for a video display monitor (not shown). Format converter 9
Is input to the graphic section 10, and a graphic for on-screen is added and output as necessary. The output of the graphic unit 10 is subjected to analog conversion processing by the D / A video output processing unit 11. The analog video signal output from the D / A video output processing unit 11 is output from an analog video output terminal 12.

[0007] Copy prohibition information indicating whether or not the received signal (video content) is copy prohibition is extracted by the demultiplexer 4 and input to the controller 13. If the copy is prohibited, the control unit 13 controls the D / A video output processing unit 11 so as to add a copy protection signal such as a macro vision method to the analog video signal and output the analog video signal. The control unit 13 also controls on / off of the power supply unit 14. The power supply unit 14 supplies power to each unit of the circuit.

[0008]

If the received digital broadcast signal is a 480I or 480P SD format, the analog video signal output from the analog video output terminal 12 is prevented from being copied by a recording device such as a VTR. be able to. However, 720P and 1080I high-definition formats (HD format)
However, since effective copy protection such as that of the macro vision system has not been established, there has been a problem that analog copy can be performed even for copy-protected video content.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has been made in consideration of the above-described problems, and has been made in consideration of the above-described problems. The purpose is to provide a machine. Another object of the present invention is to provide a digital broadcast receiver capable of avoiding a problem that a user mistakenly considers a failure as a failure and a problem that a video is not displayed on a monitor in preventing an analog copy of video content whose copying is prohibited. And

[0010]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems of the prior art, the present invention provides (a) a decoding section (8) for decoding a digital video signal and an image decoded by the decoding section. A format conversion unit (9) for format-converting the signal, a discrimination unit (13) for judging whether or not copy is prohibited based on the copy prohibition information extracted from the digital broadcast signal, and judging that the copy is prohibited by the discrimination unit In the digital broadcast receiver provided with a copy protection signal adding unit (11) for adding a copy protection signal when the copy is prohibited, if the determination unit determines that the copy is prohibited, the copy is forced regardless of the format of the digital video signal. Scan line 48
The format converter is controlled so as to convert the data into a standard format which is progressive with 0 interlaces or 480 scanning lines, and the copy is performed so as to add the copy protection signal to the video signal converted into the standard format. The present invention provides a digital broadcast receiver comprising a control unit (13) for controlling a protection signal adding unit, and (b) a decoding unit (8) for decoding a digital video signal; Format converter (9) for format-converting the decoded video signal
A determination unit (13) for determining whether or not copy is prohibited based on the copy prohibition information extracted from the digital video signal.
A copy protection signal adding unit (11) for adding a copy protection signal to a video signal when the determination unit determines that copying is prohibited, and an on-screen signal generating unit (10) for generating an on-screen signal. In the digital broadcast receiver, when the determination section determines that the copy is prohibited, the control section controls the on-screen signal generation section to generate an on-screen signal indicating that the video signal is a copy-prohibited video signal. (C) a decoding section (8) for decoding a digital video signal, and a format for format-converting the video signal decoded by the decoding section. A converter (9), and a copy prohibition information extracted from the digital video signal. Discriminator for discriminating whether the copy prohibited by the (13), the copy protection signal adder for adding a copy protection signal to the video signal if it is determined that copy prohibited by the determination unit (11)
And a luminance signal / color signal separation output terminal (12) for outputting a video signal output from the format conversion unit.
s) and at least one of a composite video signal output terminal (12 cps), a second video output terminal that is a component video signal output terminal (12 cpn), and output from the format conversion unit. A video output processing unit (11) for processing the output video signal to output to the outside via the first and second video output terminals. Connection detection unit (1) that detects plug connection
6), if the discrimination unit determines that copying is prohibited, forcibly convert the digital video signal into a standard format which is interlaced with 480 scanning lines or progressive with 480 scanning lines regardless of the format of the digital video signal. Controlling the format conversion section, and when the connection detection section detects that the plug is connected to the first video output terminal, the video signal converted to the standard format is transmitted to the first video output terminal. And a control section (13) for controlling the video output processing section so as to output from the video output terminal.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A digital broadcast receiver according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing an embodiment of a digital broadcast receiver according to the present invention;
FIG. 2 is a flowchart for explaining a more preferred embodiment of the embodiment shown in FIG. 1, and FIG. 3 is a diagram showing a screen display example for explaining a more preferred embodiment of the embodiment shown in FIG. 4 is a block diagram showing another embodiment of the digital broadcast receiver according to the present invention, and FIG. 5 is a connection detecting section 16 shown in FIG.
FIG. 3 is a circuit diagram showing a specific configuration example of FIG. 1 and 4, the same parts as those in FIG. 6 are denoted by the same reference numerals.

In FIG. 1, a digital broadcast signal from a BS is received by a BS antenna (not shown), and a BS-IF signal output from the BS antenna is input to a front end unit 2 via a BS-IF input terminal 1. Is done. The front end unit 2 selects an arbitrary frequency according to a channel selection instruction signal from the control unit 13, performs I / Q detection, and outputs an I-axis and Q-axis baseband signal.

NIM (Network Interface
The module) unit 3 receives the I-axis and Q-axis baseband signals from the front end unit 2 and
Performs PSK demodulation, error correction, TS (transport stream) selection, and the like under the control of the control unit 13.
Play and output a predetermined transport stream. This transport stream is input to the demultiplex unit 4. The demultiplex unit 4 decodes the data and performs a process of sorting audio data and video data. The demultiplex unit 4 also extracts copy prohibition information described later.

The audio data output from the demultiplex unit 4 is input to an audio decoding unit 5 where the audio data is decoded and processed by a D / A audio output processing unit 6 for analog conversion. The analog audio signal output from the D / A audio output processing unit 6 is output from an analog audio output terminal 7.
Two terminals of the analog audio output terminal 7 are output terminals for left and right audio data.

On the other hand, the video data output from the demultiplex unit 4 is input to an MPEG-video decoding unit 8 and subjected to MPEG2 decoding processing. MPE
The G-video decoding unit 8 extracts the format information of the input video data and inputs the format information to the control unit 13. Although the format information can be extracted by the demultiplexer 4, it is preferable that the format information be extracted by the MPEG-video decoder 8. The output of the MPEG-video decoding unit 8 is input to the format conversion unit 9 and converted into a video format suitable for a video display monitor (not shown) under the control of the control unit 13. However, if the received digital broadcast signal is copy-prohibited, the format converter 9 may not convert the digital broadcast signal into a video format suitable for a video display monitor. This will be described later.

The output of the format conversion section 9 is input to a graphic section 10 and output with a graphic (on-screen signal) for on-screen added as necessary. The output of the graphic unit 10 is subjected to analog conversion processing by the D / A video output processing unit 11. The analog video signal output from the D / A video output processing unit 11 is output from an analog video output terminal 12.

The three analog video output terminals 12 include a Y / C separation output terminal (so-called S terminal) 12s for separating and outputting a luminance (Y) signal and a color (C) signal, and a Y / C separation output terminal 12s.
A composite video signal output terminal 12cps in which a signal and a C signal are combined, and a component video signal output terminal 12cpn in which a Y signal and two color difference signals are separated.
In addition, actually, the composite video signal output terminal 12cp
s is composed of two output terminals, and the component video signal output terminal 12cpn is composed of three output terminals. Here, for simplification, they are illustrated as one terminal each.

Copy prohibition information indicating whether or not the received signal (video content) is copy prohibition is extracted by the demultiplexer 4 and input to the controller 13. Control unit 1
Reference numeral 3 denotes a determination unit that determines copy prohibition information and determines whether or not copy prohibition is performed. If copying is prohibited, the control unit 1
3 is whatever the format of the received digital broadcast signal is, ie, 480I, 480P, 720
P, 1080I ... force 480
The format converter 8 is controlled so as to convert the format into the I (or 480P) SD format.

At the same time, the control unit 13 controls the D / A video output processing unit 11 so as to add a copy protection signal such as a macro vision method to the analog video signal and output the analog video signal. The D / A video output processing unit 11 is also a copy protection signal adding unit that adds a copy protection signal. The control unit 13 also controls on / off of the power supply unit 14. The power supply unit 14 supplies power to each unit of the circuit.

The digital broadcast receiver of the present embodiment can receive a digital video signal output from an external video signal output device 20 such as D-VHS (registered trademark of the present applicant). Has become. The video data reproduced and output by the video signal output device 20 is IE
The signal is transmitted in a signal format conforming to the EE1394 interface, and is input to the demultiplex unit 4 via an input terminal 15 conforming to the IEEE1394 interface.
When the digital video signal output from the video signal output device 20 is output from the analog video output terminal 12 instead of the digital broadcast signal received by the BS antenna, the demultiplex unit 4 does not output the signal from the NIM unit 3. , The signal from the input terminal 15 is selected, and the above-described various processes are performed.

If the digital video signal supplied from the video signal output device 20 is copy-prohibited content, 480I is forcibly applied to the digital video signal in any format, just as in the case of a digital broadcast signal.
(Or 480P) to convert the format to the SD format. Further, the control unit 13 controls the D / A video output processing unit 11 so as to add the copy protection signal to the analog video signal and output the analog video signal.

Thus, according to the digital broadcast receiver of the present invention, it is possible to prevent analog copying of video content regardless of the format of the received digital broadcast signal. Note that the video display monitor capable of displaying the HD format also supports the display of 480I and 480P, and thus does not hinder the viewing of the video content.

In the above-described embodiment, if the content is copy-prohibited, the format is converted to the 480I (or 480P) SD format. However, the video output from the analog video output terminal 12 may be stopped. Good.

By the way, 480I (or 480P)
If the format is suddenly converted to the SD format or the video output is stopped, the user may mistakenly regard it as a failure. Therefore, it is preferable to notify the user in advance when the format conversion or the video output is stopped. FIG. 2 is a flowchart showing a more preferred embodiment. In FIG. 2, it is determined in step S1 whether or not copying is prohibited. If copying is prohibited,
Move to step S2, and if copy is not prohibited, step S2
Return to 1. In step S2, the video format is determined. If the video format is other than 480I, the process proceeds to step S3. If the video format is 480I, the process returns to step S1.

In step S3, since the content is copy-inhibited, an on-screen display to convert to 480I (or 480P) or to stop video output is performed. The process in step S3 is performed by the control unit 13 controlling the graphic unit 10. Then, in step S4, 480I (or 480P)
Or stop video output.

FIG. 3A shows a screen display example when format conversion is performed, and FIG. 3B shows a screen display example when video output is stopped. In FIG. 3A, as an example, the copy prohibited content is displayed together with an on-screen display of “copy control information is included and will be converted to 480I”, and after about 3 seconds elapse, the content is indicated on the right side of the arrow. Thus, the video converted to 480I without the on-screen display is displayed. The diagram on the right side of the arrow shows a state in which the quality (resolution) of the video is reduced due to the conversion to 480I.

In the example of FIG. 3A, on-screen display is not performed after conversion to 480I.
On-screen display may be performed for a predetermined time after the conversion into I. Also, in the example of FIG. 3A, the on-screen display is performed while displaying the video in the original format before the conversion to 480I. However, the video is not displayed in the original format, but immediately. 480I
An on-screen display to the effect that the conversion into I may be performed.
However, before converting to 480I, the user must
It is preferable to perform an on-screen display to the effect of converting to I.

While video is displayed in the original format, copying is possible. However, since the on-screen signal is superimposed on the video signal itself output from the analog video output terminal 12, it is assumed that There is no problem if copied.

In FIG. 3B, the copy prohibited content is once displayed together with an on-screen display of "copy control information is included and will be converted to 480I" as an example, and after about 3 seconds have passed. As shown on the right side of the arrow, when the video output is stopped, no video is displayed on the screen (mute). The state in which no image is displayed includes, for example, blacking the screen as no signal, displaying a single color such as blue instead of the image, and the like.

As a video display monitor, 480I
Some do not support the component video signal. In the above embodiment, when the format is converted and output from the analog video output terminal 12 to the video display monitor, if the video display monitor connected to the digital broadcast receiver does not support the 480I component video signal, Even if the converted component video signal is output from the component video signal output terminal 12cpn, the video cannot be displayed.

Therefore, in order to prevent such a problem, another embodiment is configured as shown in FIG. 4, the same parts as those in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted as appropriate. 4, the connection detection unit 16 detects connection of a plug (cable) to each of the Y / C separation output terminal 12s, the composite video signal output terminal 12cps, and the component video signal output terminal 12cpn of the analog video output terminal 12.

The control unit 13 controls the connection detection unit 16 to
If the connection of either the / C separation output terminal 12s and the composite video signal output terminal 12cps is detected, the output of the component video signal is stopped, and the D / A video is output so as to output the Y / C separation signal or the composite video signal. The output processing unit 11 is controlled. When the connection between both the Y / C separation output terminal 12s and the composite video signal output terminal 12cps is detected, both the Y / C separation signal and the composite video signal are output, or only the Y / C separation signal is output. If neither the Y / C separation output terminal 12s nor the composite video signal output terminal 12cps is connected, the D / A video output processing unit 11 is controlled to output a component video signal.

Thus, even if the video display monitor does not support the 480I component video signal,
Images can be displayed. According to this embodiment,
Even if a video display monitor corresponding to the 480I component video signal is connected to the digital broadcast receiver and a plug is connected to the component video signal output terminal 12cpn, the output video signal is either a Y / C separated signal or a composite video. Signal.

The connection detecting section 16 can be simply constructed using a known technique. In the case of the Y / C separation output terminal 12s, as is well known, the connection can be detected by determining the DC voltage level of the pin included in the terminal. The connection of the composite video signal output terminal 12cps and the component video signal output terminal 12cpn can be easily detected by a circuit configuration as shown in FIG.

In FIG. 5, one terminal of a switch S1 has a resistor R1 (for example, 10 Ω) connected to a power supply voltage Vcc.
kΩ), and the other terminal is connected to a resistor R2 (for example, 100 kΩ) having one end grounded. A resistor R3 (for example, 75Ω) is connected to the emitter of the transistor Q1.
And the resistor R4. One end of a capacitor C1 is connected to the resistor R3, and the other end of the capacitor C1 is connected between the switch S1 and the resistor R2. The voltage between the switch S1 and the resistor R2 is supplied to a control unit 13 including, for example, a microcomputer. Composite video signal output terminal 12cps (component video signal output terminal 12c
When the plug is connected (similarly to pn), the switch S1 is opened and the potential of the video signal changes, so that it is possible to detect whether or not the plug is connected.

[0036]

As described in detail above, the digital broadcast receiver of the present invention forcibly interlaces 480 scanning lines regardless of the format of a digital video signal when it is determined that copying is prohibited. Scan line 48
The format conversion unit is controlled so as to convert the data into a standard format which is 0 progressive,
A control unit is provided to control the copy protection signal addition unit to add a copy protection signal to the video signal converted to the standard format, so that even if the received or input digital video signal is a signal of any format In addition, it is possible to prevent analog copying of copy-protected video contents.

Further, a control unit is provided for controlling the on-screen signal generating unit so as to generate an on-screen signal for notifying that the image signal is a copy-inhibited video signal when it is determined by the determining unit that copying is prohibited. Therefore, it is possible to avoid a problem that the user misunderstands as a failure. Further, a connection detection unit for detecting connection of a plug to a first video output terminal, which is at least one of a luminance signal / color signal separation output terminal and a composite video signal output terminal, is provided. When it is detected that the plug is connected, a control unit for controlling the video output processing unit is provided so as to output the video signal converted into the standard format from the first video output terminal. It is possible to display an image even on a monitor that does not support the above, and it is possible to avoid a problem that an image is not displayed on some monitors.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention.

FIG. 2 is a flowchart for explaining a more preferred embodiment of the embodiment shown in FIG. 1;

FIG. 3 is a diagram showing a screen display example for explaining a more preferred embodiment of the embodiment shown in FIG. 1;

FIG. 4 is a block diagram showing another embodiment of the present invention.

FIG. 5 is a circuit diagram showing a specific configuration example of a connection detection unit 16 in FIG. 4;

FIG. 6 is a block diagram showing a conventional example.

[Explanation of symbols]

Reference Signs List 1 BS-IF input terminal 2 Front end unit 3 NIM unit 4 Demultiplex unit 5 Audio decoding unit 6 D / A audio output processing unit 7 Analog audio output terminal 8 MPEG-video decoding unit 9 Format conversion unit 10 Graphic unit (ON Screen signal generation unit) 11 D / A video output processing unit (copy protection signal addition unit) 12 Analog video output terminal 12cpn Component video signal output terminal 12cps Composite video signal output terminal 12s Luminance signal / color signal separation output terminal (S terminal) 13 control unit (determination unit) 14 power supply unit 15 input terminal 16 connection detection unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 7/08 H04N 7/08 Z 7/081

Claims (5)

[Claims] A decoding section for decoding a digital video signal; a format conversion section for format-converting the video signal decoded by the decoding section; and whether or not copy is prohibited by copy prohibition information extracted from the digital video signal. And a copy protection signal adding unit that adds a copy protection signal to a video signal when the determination unit determines that copying is prohibited. If it is determined that there is
Regardless of the format of the digital video signal, 480 interlaced scanning lines or 48 scanning lines are forcibly applied.
Controlling the format conversion unit to convert the video signal into a standard format which is 0 progressive, and controlling the copy protection signal adding unit to add the copy protection signal to the video signal converted into the standard format. A digital broadcast receiver characterized by comprising a unit. 2. A decoding section for decoding a digital video signal, a format conversion section for format-converting the video signal decoded by the decoding section, and whether or not copy is prohibited by copy prohibition information extracted from the digital video signal. A copy protection signal addition unit that adds a copy protection signal to a video signal when the determination unit determines that copying is prohibited, and an on-screen signal generation unit that generates an on-screen signal. In the digital broadcast receiver, if it is determined that the copy is prohibited by the determination unit,
A digital broadcast receiver, comprising: a control unit that controls the on-screen signal generation unit so as to generate an on-screen signal indicating that the video signal is a copy-prohibited video signal. 3. The control section forcibly performs interlacing of 480 scanning lines or progressive of 480 scanning lines irrespective of the format of the digital video signal when the determination section determines that copying is prohibited. The format converter is controlled to convert the video signal into a standard format, and at least one of before and after the video signal is converted into the standard format by the format converter, the copy-protected video signal is displayed. 3. The digital broadcast receiver according to claim 2, wherein an on-screen signal is generated to notify the digital broadcast. 4. The digital broadcast receiver according to claim 2, wherein an output of the video signal is stopped after generating an on-screen signal indicating that the video signal is a copy-prohibited video signal. 5. A decoding section for decoding a digital video signal, a format conversion section for format-converting the video signal decoded by the decoding section, and whether or not copy is prohibited by copy prohibition information extracted from the digital video signal. A copy protection signal adding unit that adds a copy protection signal to a video signal when the determination unit determines that copying is prohibited, and a video signal output from the format conversion unit. A first video output terminal that is at least one of a luminance signal / color signal separation output terminal and a composite video signal output terminal; a second video output terminal that is a component video signal output terminal; External video signal through the first and second video output terminals. A digital broadcast receiver comprising: a video output processing unit for performing processing for outputting to a first video output terminal; a connection detection unit that detects connection of a plug to the first video output terminal; and the determination unit determines that copying is prohibited. When done
Regardless of the format of the digital video signal, 480 interlaced scanning lines or 48 scanning lines are forcibly applied.
Controlling the format conversion unit so as to convert the format into zero progressive standard format, and when the connection detection unit detects that a plug is connected to the first video output terminal, A digital broadcast receiver, comprising: a control unit that controls the video output processing unit so as to output a video signal converted to a format from the first video output terminal.