JP2006013845A - Analog / digital television receiver - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an analog / digital television receiver whereby a user can carry out switching between a digital broadcast and an analog broadcast without feeling a sense of incongruity. <P>SOLUTION: A signal comparator circuit 5 discriminates whether or not both video signals outputted from an analog tuner 1 and a digital tuner 2 are coincident with each other, and a signal delay circuit 4 applies delay processing to the video signal outputted from the analog tuner 1 until both the video signals are coincident with each other. Thus, even when a changeover device 6 switches broadcast programs, since no deviation is caused in video and audio exhibited to the user through a display apparatus 7 and a speaker 8, the user can carry out switching between the broadcast programs without feeling a sense of incongruity. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an analog / digital television receiver that performs reception switching between analog broadcasting and digital broadcasting.

Conventionally, as a television receiver that performs reception by switching between analog broadcasting and digital broadcasting, for example, there is one as described in JP-A-2001-309254.
In some cases, analog broadcasting and digital broadcasting are broadcasting the same program.
In this case, the reception state of both the digital receiver that receives the digital broadcast and the analog receiver that receives the analog broadcast is monitored, and the television received by the receiver that is in a good reception state out of both receivers. The program was provided to the user.
JP 2001-309254 A

  However, in such a conventional analog / digital television receiver, the receiver is switched based on the reception state. However, since digital broadcasting is complicated in video processing, digital broadcasting is compared with analog broadcasting. It took a long time to display the video received on the screen. For this reason, if the receiver is simply switched from digital to analog or analog to digital, the displayed image will be skipped or the same video will be displayed twice in a short time. However, there was a problem that caused a sense of incongruity.

  Accordingly, an object of the present invention is to provide an analog / digital television receiver capable of switching between digital broadcasting and analog broadcasting without causing the viewer to feel uncomfortable.

  The present invention includes an analog tuner, a digital tuner, a reception state determination unit that determines a reception state of the analog tuner and a reception state of the digital tuner, and a video signal delay unit that performs a delay process on the video signal received by the analog tuner. And switching means for switching so that the television broadcast received by either the analog tuner or the digital tuner is selected based on the determination result of the reception state determination means, and is received by the analog tuner by the video signal delay means. The switching means performs switching after delaying the video signal.

  According to the present invention, by switching the broadcast after delaying the video signal received by the analog tuner by the video signal delay means, the user can switch between the digital tuner and the analog tuner without feeling uncomfortable. Can do.

Next, embodiments of the present invention will be described by way of examples.
It is assumed that the analog / digital television receiver is mounted on the vehicle.
FIG. 1 shows the overall configuration of the embodiment.
An analog tuner 1 that receives an analog television broadcast program is connected to a switching device 6 via a signal delay circuit 4 and a signal comparison circuit 5.
A digital tuner 2 that receives a digital broadcast television broadcast program is connected to the switching device 6.
The signal delay circuit 4 delays the video signal (including the audio signal) output from the analog tuner 1. The signal comparison circuit 5 compares the video signal output from the analog tuner 1 with the video signal output from the digital tuner 2.

The signal delay circuit 4 and the signal comparison circuit 5 are connected by a feedback circuit 9.
The feedback circuit 9 delays the video signal output from the analog tuner 1 with respect to the signal delay circuit 4 until it is determined by the signal comparison circuit 5 that the video signals output from the analog tuner 1 and the digital tuner 2 match. Give instructions.

The analog tuner 1 and the digital tuner 2 are connected to a reception state determination unit 3 that compares reception states of the tuners.
The reception state determination unit 3 instructs the switching unit 6 to switch reception from digital broadcast to analog broadcast when the reception state of the digital broadcast received by the digital tuner 2 is deteriorated.

The switching device 6 switches which of the broadcast programs received by the analog tuner 1 or the digital tuner 2 is to be used to select the broadcast program received by the receiver.
The broadcast program selected by the switcher 6 is presented to the user from the display 7 and the speaker 8.

Next, a temporal shift between video signals output from the analog tuner 1 and the digital tuner 2 will be described.
FIG. 2 is a diagram illustrating a temporal shift of the video signal generated when the digital tuner 2 performs digital processing of the video signal.
Since the digital tuner 2 performs digital processing of the received video signal, the output video signal has a time delay T0 compared to the analog tuner 1.

FIG. 3 is a diagram showing a temporal shift of the video signal generated when the analog tuner 1 receives the reflected wave.
The analog tuner 1 receives a reflected wave obtained by reflecting an analog radio wave from the building A or the like, thereby causing a delay of a time delay T1 in an output video signal compared to a case where the analog radio wave is directly received. .
In addition, since the surrounding situation changes as the vehicle equipped with the analog / digital television receiver moves, the time delay T1 due to the reflected wave always fluctuates.

Next, the operation of each unit when the reception state deteriorates during viewing of a digital broadcast program and switching to reception of an analog broadcast program will be described.
FIG. 4 is a flowchart showing a broadcast program switching operation.
This process is started when, for example, the channel of the broadcast program is changed by the user.
In step 100, the signal comparison circuit 5 determines whether the video signal output from the analog tuner 1 matches the video signal output from the digital tuner 2.
If the two video signals do not match, the process proceeds to step 105.

In step 105, the feedback circuit 9 instructs the signal delay circuit 4 to delay the video signal output from the analog tuner 1 by a predetermined delay time t.
In step 106, the signal delay circuit 4 determines whether or not the delay time T (the total of the delay times t) by which the video signal has been delayed by an instruction from the feedback circuit 9 is equal to or greater than a predetermined time. If YES, go to step 107.

On the other hand, if it is less than the predetermined time, the process returns to step 100. If the video signals output from the analog tuner 1 and the digital tuner 2 do not match, step 105, until the delay time T becomes equal to or longer than the predetermined time. In 106, the delay processing of the video signal output from the analog tuner 1 is repeatedly performed.
This delay process is executed so that T0-T1 = 0.

  In step 107, the signal delay circuit 4 stops the delay processing of the video signal output from the analog tuner 1, and the broadcast program received by the analog tuner 1 is different from the broadcast program received by the digital tuner 2. It is determined that the program has a broadcast content.

In step 108, the signal delay circuit 4 also determines that the analog tuner 1 is not a digital simulcast (the same broadcast as the analog broadcast) even when the reception state of the broadcast program received by the digital tuner 2 becomes poor. The user is notified that it is impossible to switch the reception to the user.
This notification is performed using the display 7 and the speaker 8.
After the notification in step 108, the process is terminated while the broadcast reception state by the digital tuner 2 is maintained.

  On the other hand, if it is determined in step 100 that the video signal output from the analog tuner 1 matches the video signal output from the digital tuner 2, the reception state determination unit 3 is received by the digital tuner 2 in step 101. It is determined whether or not the reception state of the digital broadcast has deteriorated. If the reception state has deteriorated, the process proceeds to step 102. If the reception state is not bad, the process returns to step 100.

In step 102, the reception state determination unit 3 instructs the switching device 6 to switch reception from digital broadcasting to analog broadcasting.
Thereby, the broadcast program received by the analog tuner 1 is presented through the display 7 and the speaker 8.
Further, the video signal output from the analog tuner 1 is delayed by the processing in the above-described steps 100, 105, and 106, and the video signal output from the analog tuner 1 and the digital tuner 2 is not temporally shifted. Therefore, when switching from digital broadcasting to analog broadcasting, there is no deviation in the video and audio presented through the display 7 and the speaker 8.

Next, in step 103, the reception state determination unit 3 determines whether or not the reception state of the digital broadcast received by the digital tuner 2 has been recovered. Instruct to switch reception from broadcasting to digital broadcasting.
Thereby, the broadcast program received by the digital tuner 2 is presented through the display 7 and the speaker 8.

If the reception state of the digital broadcast received by the digital tuner 2 has not recovered, the processing in step 103 is repeated.
After instructing switching to digital broadcasting in step 104, the process returns to step 100 and the above-described processing is repeated.
In this embodiment, steps 101 and 103 constitute the reception state determination means in the present invention, and steps 102 and 104 constitute the switching means in the present invention. Steps 106 and 107 constitute video signal delay means in the present invention, and step 100 constitutes video signal comparison means in the present invention. Further, step 105 constitutes feedback means in the present invention, and step 108 constitutes notification means in the present invention.

This embodiment is configured as described above, and whether or not the video signals output from the analog tuner 1 and the digital tuner 2 by the signal comparison circuit 5 match when the user is watching a digital broadcast program. The feedback circuit 9 instructs the signal delay circuit 4 to delay the video signal output from the analog tuner 1 until both video signals match.
In this way, even when a delay occurs in the video signal output from the digital tuner 2 by the digital tuner 2 performing digital processing of the video signal, the video signal output from the digital tuner 2 by the signal delay circuit 4. Since the delay of the video signal output from the analog tuner 1 is performed so as to match with the above, even when switching from digital broadcasting to analog broadcasting, video and audio may be skipped, or in a short time The same video and audio are not presented twice, and the user does not feel uncomfortable.

  Further, even when a delay occurs in the video signal output from the analog tuner 1 due to the analog tuner 1 receiving the reflected wave, it matches the video signal output from the digital tuner 2 by the signal delay circuit 4. Since the video signal output from the analog tuner 1 is delayed, the broadcast can be switched without the user feeling uncomfortable.

  Further, the signal delay circuit 4 determines that the broadcast programs received by the analog tuner 1 and the digital tuner 2 are different when the delay time of the video signal output from the analog tuner 1 exceeds a predetermined time. As a result, the delay processing of the video signal does not continue to be performed repeatedly, and the processing efficiency can be improved.

  The signal delay circuit 4 also presents to the user that it is impossible to switch reception to the analog tuner 1 when the delay time of the video signal output from the analog tuner 1 exceeds a predetermined time. By doing so, the user can recognize why switching from digital broadcasting with poor reception to analog broadcasting is not performed, and does not feel uncomfortable about not switching broadcast programs. .

It is a figure which shows the whole structure of an Example. It is a figure which shows the time gap | deviation of the video signal generate | occur | produced by digital processing. It is a figure which shows the time gap | deviation of the video signal generate | occur | produced by receiving a reflected wave. It is a flowchart which shows switching operation | movement of a broadcast program.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Analog tuner 2 Digital tuner 3 Reception state determination part 4 Signal delay circuit 5 Signal comparison circuit 6 Switching machine 7 Display 8 Speaker 9 Feedback circuit

Claims (8)

An analog tuner, a digital tuner, a reception state determination unit that determines a reception state of the analog tuner and a reception state of the digital tuner, and a determination result of the reception state determination unit, either the analog tuner or the digital tuner On the other hand, in an analog / digital television receiver having switching means for switching so as to select a received television broadcast,
Video signal delay means for delaying the video signal received by the analog tuner,
An analog / digital television receiver, wherein the switching is performed after the video signal received by the analog tuner is delayed by the video signal delay means. A video signal comparing means for comparing the video signal received by the analog tuner with the video signal received by the digital tuner and determining whether or not both video signals match;
If it is determined by the video comparison means that the two video signals do not match, the analog signal in a direction in which the video signal received by the analog tuner and the video signal received by the digital tuner match. 2. The analog / digital television receiver according to claim 1, further comprising feedback means for giving a delay instruction for delaying the video signal received by the tuner to the video signal delay means. The feedback means performs a delay instruction for delaying the video signal received by the analog tuner by a predetermined delay time until the video signal comparing means determines that the two video signals match. The analog / digital television receiver according to claim 2. The video signal delay means includes a television broadcast received by the analog tuner and a television broadcast received by the digital tuner when the delay time of the video signal received by the analog tuner is a predetermined time or more. Is not the same broadcast,
4. The analog / digital television receiver according to claim 3, wherein the switching means does not switch between the digital tuner and the analog tuner. Informing means for informing the user that the broadcast is not switched,
The notification means performs notification when it is determined that the television broadcast received by the analog tuner by the video signal comparison means and the television broadcast received by the digital tuner are not the same broadcast. The analog / digital television receiver according to claim 4, wherein the receiver is an analog / digital television receiver. 6. The broadcast switching performed by the switching means is switching from a television broadcast received by the digital tuner to a television broadcast received by the analog tuner. Analog and digital TV receiver. The switching means switches from the television broadcast received by the digital tuner to the television broadcast received by the analog tuner when the reception status determination means determines that the reception status of the digital tuner has deteriorated. The analog / digital television receiver according to claim 6, wherein: When the television broadcast received by the analog tuner is being performed by switching the switching means,
The switching unit switches from the television broadcast received by the analog tuner to the television broadcast received by the digital tuner when the reception state determination unit determines that the reception state of the digital tuner has been recovered. The analog / digital television receiver according to claim 7.

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