JP2002247465A - Television receiver and method for displaying reception state of the television receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a television receiver that can inform a user of whether a video image of a higher layer or a video image of a lower layer is being reproduced in the case of a broadcast program adopting the hierarchical trans mission system. SOLUTION: The C/N of a received signal is discriminated to select reproduction of a video image at the higher layer or at the lower layer. Then an indication of the video image at the higher layer or at the lower layer that is reproduced is made on an OSD image or a display section of a set main body. Thus, the user can recognize whether the video image received currently is a video image of the higher layer or the lower layer. Even when the video image of the higher layer is switched to the video image of the lower layer due to rainfall or the like, mis-recognition of a fault is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
dcast Satellite) The present invention relates to a television receiver and a reception state display method suitable for receiving an image of a hierarchical transmission system such as digital broadcasting.

[0002]

2. Description of the Related Art For example, in BS digital broadcasting in which satellite television broadcasting is performed using a Ku band in the 12 GHz band, when there is heavy rainfall or snowfall, attenuation of radio waves becomes severe, and service continuation becomes difficult. Therefore, in BS digital satellite broadcasting, BPSK (Binary Phase Shift
Keying) and QPSK (Quadrature Phase Shift Key)
ing) and TC-8PSK (trellis 8-phase PSK) to perform hierarchical transmission.

[0003] In other words, in TC-8PSK modulation, the amount of information per symbol increases, and high-quality images can be sent.
If there is attenuation due to rainfall, the error rate is significantly deteriorated. On the other hand, in BPSK and QPSK, the amount of information per symbol is small and high-quality images cannot be transmitted. However, even if attenuation due to rainfall occurs, the error rate does not decrease so much.

Therefore, on the transmitting side, as shown in FIGS. 8 and 9, one TS packet is mapped to correspond to one slot. One TS packet is composed of 188 bytes, and is a 16-byte error correction code (outer code).
Is added. In the TS packet, the first byte is a synchronization byte, and since this part is a fixed value, a part of this part is replaced with frame synchronization or TMCC. Then, a modulation scheme and an encoding scheme are assigned to each slot. The type of the modulation scheme and the coding rate assigned to each slot are described in TMCC (Transmission
and Multiplexing Configuration Control) signal. One frame is composed of 48 slots, a superframe is composed of eight frames, interleaving is performed for each slot position, and a convolutional code is added as an inner code and transmitted.

On the receiving side, according to the CN ratio of the received signal,
The demodulation process is switched. That is, when the CN ratio is good, the slot of TC-8PSK is used and the TC-8PSK is used.
Demodulation processing is performed by PSK. When the CN ratio deteriorates due to rainfall, BPSK and QPSK slots are used,
SK or QPSK demodulation processing is performed.

[0006] According to such a hierarchical transmission system, high-quality video is transmitted in a high hierarchy and video of a bit rate is transmitted in parallel in a low hierarchy. For this reason, for example, even if a video transmitted in a higher hierarchy cannot be received due to rain attenuation or the like, but a lower hierarchy video can be demodulated, the lower hierarchy video is demodulated to provide a service such as rain attenuation. Interruption can be prevented.

[0007]

As described above, the hierarchal transmission system is adopted in the BS digital broadcasting, and a high-layer image and a low-layer image are transmitted in parallel. On the receiving side, the high-layer video and the low-layer video are switched according to the CN ratio, thereby preventing interruption of service due to rainfall attenuation or the like.

However, there is a considerable difference in video quality between a high-layer video and a low-layer video. For this reason, if the image is switched from a high-layer image to a low-layer image due to rainfall or the like, the user watching the broadcast may erroneously recognize that a failure has occurred.

Therefore, an object of the present invention is to inform a user whether a high-layer video or a low-layer video is being reproduced in the case of a broadcast employing a hierarchical transmission system. It is an object of the present invention to provide a method for displaying a reception state of a television receiver which can perform the above.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a television receiver for receiving a video signal of a hierarchical transmission system in which a high-layer video and a low-layer video are sent in parallel.
Determining means for judging a reception state; reproducing means for selectively reproducing a high-layer image and a low-layer image according to the reception state; and whether the currently reproduced image is a high-layer image or a low-layer image. And a display means for displaying whether or not the image is an image.

According to the present invention, in a receiving state display method of a television receiving apparatus for receiving a video signal of a hierarchical transmission system in which a high-layer video and a low-layer video are sent in parallel, a step of determining a receiving state Selectively demodulating the high-layer video and the low-layer video according to the reception state, and displaying whether the currently demodulated video is a high-layer video or a low-layer video And a receiving state display method.

[0012] An indication is displayed on the OSD screen or the display section of the main body of the set to indicate whether a high-level video or a low-level video is being reproduced. This allows the user to know whether the currently received video is a high-layer video or a low-layer video. Therefore, even when the image is switched from a high-layer image to a low-layer image due to rainfall or the like, it is not erroneously recognized as a failure.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a BS digital satellite broadcast receiving system to which the present invention is applied.

In FIG. 1, a radio wave from a BS digital satellite is received by a parabolic antenna 11, converted into an intermediate frequency signal by a low noise converter 12 attached to the parabolic antenna 11, and transmitted via a cable 10 to the BS digital satellite. It is supplied to the tuner 1. The BS digital satellite tuner 1 decodes a video signal and an audio signal from the received signal.

[0015] The video signal decoded by the BS digital satellite tuner 1 is supplied to a television receiver 2. The television receiver 2 reproduces a screen based on the video signal.

In BS digital broadcasting, SDTV (Stan)
dard Definition Television) and HDTV (Hi
gh Definition Television) broadcasts are supported.

That is, in BS digital broadcasting, 10
80i (effective pixel number 1920 × 1080 aspect ratio 16: 9 interlace scan) video format, 480p (effective pixel number 720 × 480 aspect ratio 16: 9 progressive scan) video format, and 480i (effective pixel number 720 × 480) (16: 9 aspect ratio or 4: 3 interlace scan)
Video format and 720p (1280 effective pixels)
A video format of × 720 aspect ratio 16: 9 progressive scan) is supported.

It is desirable to use a television receiver 2 which can support each of these formats and further has a D terminal.

The D terminal receives a luminance signal Y, color difference signals Pb, P
r that can handle component video signals
Five types from D1 to D5 are prepared according to the broadcast format. The D terminal includes a signal for identifying a video format. The television receiver 2 equipped with a D terminal can easily cope with various video formats by connecting the BS digital satellite tuner 1 and the television receiver 2 using the D terminal.

The audio signal decoded by the BS digital satellite tuner 1 is supplied to an audio amplifier 3. The audio signal of each channel is amplified by the audio amplifier 3.

In BS digital broadcasting, MPEG2 AAC is adopted as an audio encoding method. MPE
In G2 AAC, L (front left), R (front right), C
(Center), RL (rear left), RR (rear right), SW
(5 + 1) channel of (subwoofer) is supported. It is desired to use an audio amplifier 3 that can handle such a (5 + 1) channel.

From the audio amplifier 3, L (front left), R (front right), C (center), RL (back left),
The audio signal of each channel of RR (rear right) and SW (subwoofer) is amplified and output. The audio output of each of these channels is transmitted to the front left and right speakers 5.
A, 5B, center speaker 5C, rear left and right speakers 6
A, 6B, and the subwoofer 7. Sound of each channel is output from the front left and right speakers 5A and 5B, the center speaker 5C, the rear left and right speakers 6A and 6B, and the subwoofer 7.

FIG. 2 shows the configuration of the BS digital satellite tuner 1. In FIG. 2, for example, 12GH
The digital satellite broadcast radio wave transmitted via the satellite in the z-band radio wave is received by the parabolic antenna 11 and the low noise converter 1 attached to the parabolic antenna 11
2, the signal is converted into an intermediate frequency signal of, for example, a 1 GHz band. The output of the low-noise converter 12 is transmitted via a cable 10 to an antenna terminal 2 of a BS digital satellite tuner 1.
1 is supplied.

The signal from the antenna terminal 21 is supplied to a tuner circuit 22. By the tuner circuit 22, based on a control signal for frequency setting from the controller 20,
From the received signals, a signal having a desired carrier frequency is selected.

The output of the tuner circuit 22 is supplied to a demodulation circuit 23. In the demodulation circuit 23, BPSK and QPSK
And demodulation processing of TC-8PSK (trellis 8-phase PSK).

That is, in BS digital satellite broadcasting,
Hierarchical transmission is performed using BPSK, QPSK, and TC-8PSK. In TC-8PSK modulation, 1
Although the amount of information per symbol increases, the error rate deteriorates when there is attenuation due to rainfall. On the other hand, BP
In the case of SK or QPSK, the amount of information per symbol decreases, but the error rate does not decrease so much even if attenuation due to rainfall occurs.

On the transmitting side, each TS packet is mapped to a frame composed of 48 slots, with one TS packet corresponding to one slot. A modulation scheme and an encoding scheme can be assigned to each slot.
The type and coding rate of the modulation scheme assigned to each slot are transmitted by a TMCC signal. Then, a super frame is configured in units of 8 frames, and interleaving is performed for each slot position.

Information on the CN ratio of the received signal is sent from the tuner circuit 22 to the controller 20. The controller 20 determines a modulation scheme according to the CN ratio of the received signal, and switches a demodulation slot according to the modulation scheme.

That is, when the CN ratio is good, TC-
8PSK slot is used, and the demodulation circuit 23 uses TC
Demodulation processing is performed at -8PSK. When the CN ratio gets worse due to rainfall, BPSK and QPSK slots are used,
The demodulation circuit 23 performs demodulation processing of BPSK and QPSK.

The output of the demodulation circuit 23 is output to the error correction circuit 2
4 is supplied. The error correction circuit 24 performs an error correction process. As an error correction coding method, a Reed-Solomon code (204, 188) is used as an outer code, and a trellis code and a convolutional code are used as an inner code.

The output of the error correction circuit 24 is supplied to a descrambler 25. In descrambler 25, CAS
(Condition Access System) control is performed.

That is, in the case of conditional access, the TS packet stream is encrypted. Personal information is IC
It is stored in the card 27, and the IC card 27 is mounted via the card interface 35. The descrambler 25 stores the received ECM (Entitlement Cont.
rol Message) and EMM (Entitlement ManagementMe)
ssage) is supplied, and the descrambling key data stored in the IC card 27 is supplied. In the case of the limited reception, the descrambler 25 performs descrambling using the received ECM or EMM and the information of the IC card 27.

The descrambled TS packet stream is sent from a descrambler 25 to a demultiplexer 28.
Sent to The demultiplexer 28 is connected to the controller 2
A desired packet is separated from the stream from the descrambler 25 based on a command from 0.

A packet identifier (PID) is described in the header of the transmission packet. Demultiplexer 28
Then, video packets, audio packets, and data packets of a desired program are separated based on the PID.

A video packet of a desired program is sent to a video decoder 29, and an audio packet is sent to an audio decoder 30. The data packet is
It is sent to the controller 20.

The video decoder 29 receives a video packet from the demultiplexer 28, performs an MPEG2 decoding process, and reproduces a video signal. The reproduced video signal is supplied to the adding circuit 31.

The addition circuit 31 includes an OSD circuit 32
Is supplied. The OSD circuit 32 displays various information on a screen. The display signal from the OSD circuit 32 is superimposed on the video signal from the video decoder 29 by the addition circuit 31. The output of the adding circuit 31 is output from the output terminal 33.

The audio decoder 30 receives the audio packet from the demultiplexer 28,
G2 AAC is decoded to form an audio signal. The decoded audio signal is output from the audio output terminal 34.

Input for operating the BS digital satellite tuner 1 is performed by an input key 41 and a remote controller 42. The infrared command signal from the remote controller 42
At the remote controller interface 44,
It is sent to the controller 20. The controller 20
Is provided with a display unit 45.

The setting state and the receiving state of the BS digital satellite tuner 1 are displayed on the display 45 based on the setting information from the controller 20, and the OSD circuit 32
Accordingly, it is possible to perform on-screen display on a television screen.

An IEEE (Institute of Electronics) for connecting to an external device such as a VTR or a personal computer.
An interface 46 of the Electrical and Electronics Engineers (1394) and a modem 47 are provided for managing viewing information and transmitting information for interactive programs.

As described above, in BS digital satellite broadcasting, hierarchical transmission is performed by TC-8PSK modulation and BPSK or QPSK modulation, such as transmitting high-layer video and low-layer video. I have. When the CN ratio is good, a high-layer high-resolution video is reproduced using TC-8PSK. If the CN ratio deteriorates due to rainfall or the like, a low-hierarchy image that is resistant to errors is reproduced.

By adopting such a hierarchical transmission system,
The service can be continued even in case of rain attenuation.

However, there is a considerable difference in image quality between a high-layer image and a low-layer image. For this reason, when rainfall or the like occurs and the video is switched from the high-layer video to the low-layer video, the difference in the image quality is recognized by the user, and the user is erroneously recognized as having failed.

Therefore, in the embodiment of the present invention, the user is informed whether the video of the higher hierarchy or the video of the lower hierarchy is currently being reproduced.

That is, as shown in FIG. 3, a display unit 45 is provided on the front surface of the BS digital satellite tuner 1. The display unit 45 includes a date display area 52, a time display area 53, a channel display area 54, a high-layer video reception display area 55A, and a low-resolution reception display area 55B.

In the date display area 52, the current date is displayed. The time display area 53 displays the current time. In the channel display area 54, the currently set channel is displayed.

Information indicating whether the currently reproduced image is a high-layer image or a low-layer image is displayed in the high-layer image reception display area 55A and the low-resolution reception display area 55B. That is, if the currently reproduced video is a high-layer video, “Hi” is displayed in the high-layer video reception display area 55A, and the display in the low-layer video reception display area 55B is deleted. If the currently reproduced image is a low-layer image, “Lo” is displayed in the low-layer image reception display area 55B,
The display in the high hierarchy video reception display area 55A is deleted.

In this example, the display unit 45 on the front of the BS digital satellite broadcast tuner 1 displays whether a high-level video or a low-level video is being reproduced. However, as shown in FIG. 4, an LED indicator 5 is provided on the front of the BS digital satellite broadcast tuner 1.
6 may be provided, and this LED indicator 56 may be turned on to notify whether a high-layer video or a low-layer video is being reproduced.

In FIG. 4, the LED indicator 56 is
This indicates that a video of a lower hierarchy is being reproduced. If the currently reproduced image is a high-layer image, the LED indicator 56 has been deleted. When the video currently being reproduced becomes a video of a lower hierarchy, the LED indicator 56 is turned on.

In the example shown in FIG. 4, when the currently reproduced video is a video of a lower hierarchy, the LED indicator 56
Is turned on, but the LED indicator 56 may be turned on when the currently reproduced image is a high-layer image. In addition, the color of the LED indicator may be different between when a high-layer video is being reproduced and when a low-layer video is being reproduced.

At the same time, whether the video of the higher hierarchy or the video of the lower hierarchy is currently being played back is determined by
As shown in FIG. 5, the user is notified by the OSD screen.

As shown in FIG. 5, the television receiver 2
On the display screen 61, an on-screen character 62 is displayed. The on-screen character 62 includes a character of the currently set channel and a character indicating whether a high-layer video or a low-layer video is being reproduced. When the currently reproduced video is a low-layer video, for example, a “Hi” character is displayed, and when the video is a low-layer video, a “Lo” character is displayed, for example. With such an OSD screen,
The user is notified whether a high-layer video or a low-layer video is being reproduced.

In the above-described example, the display indicating whether the video of the higher hierarchy or the video of the lower hierarchy is being reproduced is displayed by the display unit 45 and the display of the television receiver 2. The display is performed on both sides of the OSD screen of the screen 61, but may be performed on either one of them.

As shown in FIG. 6, an LED indicator 63 may be provided on the front of the television receiver 1 to indicate whether the currently reproduced image is a high-layer image or a low-layer image. .

FIG. 7 is a flowchart showing a process for displaying whether a high-layer video or a low-layer video is being reproduced, as described above.

As shown in FIG. 7, it is determined whether or not BS digital satellite broadcasting has been received (step S).
1). If reception is not possible, reception disable processing is performed (step S2).

If reception has been completed, it is determined whether or not hierarchical transmission is being performed (step S3).

If the hierarchical transmission is not performed, the reproduction is performed with the high-layer video, and “Hi” indicating the high-layer video is displayed on the screen as the on-screen character 62 (step S 4). An indicator (high-level video reception display area 55A) indicating that the hierarchical video is being reproduced is displayed (step S5), and step S3 is performed.
Is returned to

When it is determined in step S3 that hierarchical transmission is being performed, it is determined whether the CN ratio is low (step S6).

If the CN ratio is not low, a high-layer video can be reproduced, so that a high-layer video is reproduced, and “Hi” indicating the high-layer video is displayed as an on-screen character 62 on the screen. (Step S4) An indicator (high-layer video reception display area 55A) indicating that the high-layer video is being reproduced is displayed (step S5), and the process returns to step S3.

When it is determined in step S6 that the CN ratio is low, reproduction of a high-layer image becomes difficult due to the influence of noise, so that reproduction of a low-layer image is performed. At this time, “L” indicating that the image is a low-level image is displayed on the screen.
"o" is displayed as the on-screen character 62 (step S7), and an indicator (low-layer video reception display area 55B) indicating that a low-layer video is being reproduced.
Is displayed (step S8), and the process returns to step S3.

As described above, in the satellite broadcast receiving system to which the present invention is applied, a display indicating whether a high-layer video or a low-layer video is being reproduced is displayed. This allows the user to know whether the currently reproduced video is a high-level video or a low-level video, and as if the video was switched from the high-level video to the low-level video due to rainfall or the like. In such a case, it will not be mistaken for a failure.

In the above example, the case of BS digital broadcasting has been described, but the present invention is not limited to the reception of BS digital broadcasting. The present invention
As long as the layered transmission method is used, the present invention is not limited to the BS digital broadcast, and can be similarly applied to other broadcasts.

[0065]

According to the present invention, a display indicating whether a video of a higher hierarchy or a video of a lower hierarchy is being reproduced is made. This allows the user to know whether the currently reproduced video is a high-level video or a low-level video, and as if the video was switched from the high-level video to the low-level video due to rainfall or the like. In such a case, it will not be mistaken for a failure.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an example of a satellite broadcast receiving system to which the present invention is applied.

FIG. 2 is a block diagram showing an example of a BS digital satellite tuner in a satellite broadcast receiving system to which the present invention is applied.

FIG. 3 is a schematic diagram used for describing a display unit provided on a BS digital satellite tuner side.

FIG. 4 is a schematic diagram used for describing a display unit provided on the BS digital satellite tuner side.

FIG. 5 is a schematic diagram used for describing an OSD screen of the television receiver.

FIG. 6 is a schematic diagram used for describing a display unit provided on the television receiver side.

FIG. 7 is a flowchart used to explain display of a reception state.

FIG. 8 is a schematic diagram used for describing a hierarchical transmission scheme.

FIG. 9 is a schematic diagram used for describing a hierarchical transmission scheme.

[Explanation of symbols]

1: digital satellite tuner, 2: television receiver, 42: remote controller, 51: display unit, 55
A: High-layer video reception display area, 55B: Low-resolution reception display area, 62: On-screen character

Claims (6)

[Claims] 1. A television receiver for receiving a video signal of a hierarchical transmission system in which a high-layer video and a low-layer video are transmitted in parallel, a determining means for determining a reception state; A reproducing means for selectively reproducing the high-layer video and the low-layer video in response thereto, and displaying whether the currently reproduced video is the high-layer video or the low-layer video. A television receiver, comprising: a display unit. 2. The television receiver according to claim 1, wherein said display means is superimposed on a reception screen. 3. The television receiving apparatus according to claim 1, wherein said display means comprises a display section of the apparatus main body. 4. A method for displaying a reception state of a television receiving apparatus for receiving a video signal of a hierarchical transmission scheme in which a high-layer video and a low-layer video are transmitted in parallel, a step of determining a reception state; Selectively demodulating the high-layer video and the low-layer video according to the reception state; and determining whether the currently demodulated video is the high-layer video or the low-layer video. Displaying a reception state. 5. The reception state display method according to claim 4, wherein said display means is superimposed on a reception screen. 6. The reception status display method according to claim 4, wherein said display means comprises a display element attached to a set body.