JP3214671B2 - Video signal transmission equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for transmitting an external video signal such as a door phone system with a TV camera, a general broadcast,
Video signal transmission provided with a TV signal transmission system for transmitting a TV signal such as a satellite broadcast or a cable TV via a coaxial cable.
It concerns the device .

[0002]

2. Description of the Related Art Recently, many homes are equipped with a door phone system equipped with a TV camera. This door phone system is effective for crime prevention and the like because it is possible to see a visitor's face and the like.

[0003]

In the case where the image of the TV camera provided in the door phone system is projected not on a dedicated monitor receiver but on a commercially available TV receiver, a TV is required.
Since the external video signal from the camera via an adapter has to be connected to the video signal input terminal provided to the TV receiver, in addition to a coaxial cable for TV signal transmission, it transmits the external video signal from the TV camera There is a problem that a coaxial cable must be wired in the house.

Further, one of the video signal input terminals of the TV receiver is occupied exclusively by the door phone as described above.
There is a problem that video equipment such as a VTR cannot be connected depending on the function of the TV receiver. The invention according to claim 1 has been made in view of the above-mentioned problem, and an object of the invention is to convert an external video signal from a TV camera to a TV using a TV signal transmission system coaxial cable for transmitting a TV signal. It can be transmitted as a signal and can be projected on a TV receiver without using a video signal input terminal on a commercially available TV receiver. In addition, an external video signal is sent as a TV signal on a viewing channel, and the TV receiver currently being viewed It is an object of the present invention to provide a video signal transmission device that can display an image on a video signal.

[0005]

To achieve the above object of the Invention The invention according to claim 1 and the TV transmission system for transmitting TV signals through a coaxial cable, film external TV camera or al
Together and a system for transmitting an image signal, the external video
Superimpose generated in the external video signal at a carrier frequency of a predetermined channel when the input signal and the image generating unit
And a head end having a mixing means for modulating the current image together with the image and transmitting the TV signal as a TV signal via the coaxial cable of the TV transmission system. The head end includes means for receiving data of the current viewing channel from the TV receiver. And set the predetermined channel as the current viewing channel and
An external video signal and the superimposed image to the TV receiver is for displaying screen.

[0006]

According to the first aspect of the present invention, there is provided a TV transmission system for transmitting a TV signal via a coaxial cable;
Together and a system for transmitting the external video signal of the camera or al, is produced at a carrier frequency of a predetermined channel when the input of the external image signal by the external video signal and an image generating unit
Mixed with the superimposed image and transmitted as a TV signal through the coaxial cable of the TV transmission system.
A head end having a coupling means, the current means for receiving the data of the viewing channel is provided, the external video signal by setting the predetermined channel current viewing channel and the super imported from the TV receiver to the headend
Since over's image and the TV receiver on screen display, a commercial TV receiver in the screen due to the switching of the received signal image of the external video signal disturbance that is connected to the TV signal transmission system of the coaxial cable The image can be projected on the TV receiver without any occurrence, so that there is no sense of incongruity at the time of switching.

[0007]

The present invention will be described below with reference to examples. Figure 2 is a block diagram of the onset illumination device, the coaxial cable 2 connected to the broadcast receiving antenna 1 has been routed to the home via the head-end 3, commercially available through splitter 3 (or distributor) TV receiver 4 and the broadcast receiving antenna 1
Is transmitted to the TV receiver 4, and a TV signal transmission system is constructed by the broadcast receiving antenna 1, the coaxial cable 2, and the splitter 5 (or distributor). UHF, VH as the broadcast receiving antenna 1
B that has a converter besides the one that receives the general broadcast of F
TV that has S antenna and transmits to coaxial cable 2
The signal includes a TV signal of the cable TV.

On the other hand, the head end 3 reproduces an external video signal obtained by imaging with a slave 8a of a two-wire doorphone using a pair of wires and a TV camera 6 attached to the slave 8a. A master unit 8b including a handset 9 for making a call between the monitor receiver 7 and the slave unit 8a is connected,
We are building a system for transmitting external video signals . The TV receiver 4 using receives data by wire, and to have a function capable of performing control such as channel settings and power, a connection terminal related to the function to the head-end 3 side via the data transmission line 10 Connected.

FIG. 1 shows a circuit configuration relating to a video signal of a video signal transmission device having two transmission systems constructed as described above, and is transmitted over a coaxial cable 2 in a head end 3. A vacant channel search circuit 11 for searching for a vacant channel from the carrier frequency of the TV signal, and an external video signal sent from the slave unit 8a via the signal line 12 is modulated by the carrier frequency to be a TV signal. Modulation circuit 13
When the incoming signal S is sent from the slave unit 8a via the signal line 12, the empty channel search circuit 11 searches for an empty channel, and modulates the signal with a carrier frequency corresponding to the searched empty channel. Control the modulation circuit 13 and output the idle channel information
U14 and a mixing circuit 15 for mixing a TV signal obtained by modulation by the modulation circuit 13 with a TV signal transmitted from the broadcast receiving antenna 1 via the coaxial cable 2 and transmitting the mixed signal to the coaxial cable 2 in the house. And converts the vacant channel information into a predetermined signal format, and
And a transmission unit 16 for transmitting to the V receiver 4.

In this reference example, as shown in FIG. 3, when the incoming signal S from the slave unit 8a of the intercom is input, the CPU 1
4 instructs the empty channel search circuit 11 to search for an empty channel. The vacant channel search circuit 11 searches for a vacant channel from the TV signal on the coaxial cable 2 and completes the search.
Give to. The CPU 14 determines a vacant channel to be used based on the data, and instructs the modulation circuit 13 on the vacant channel to be used. The modulation circuit 13 sets the TV camera 6 at the carrier frequency of a predetermined vacant channel based on this instruction.
From the external video signal, and the modulated T
The V signal is sent out onto the coaxial cable 2 through the mixing circuit 15.

The TV receiver 4 used here receives an external signal consisting of free channel information, and switches to the channel specified by the free channel information even while watching TV broadcasts, so that the TV set of the slave unit 8a of the intercom can be used. Outside of camera 6
A TV signal composed of a video signal is received, and the entire screen of the video is displayed. If the TV receiver 4 used does not have the function of receiving the data, the channel is manually switched to an empty channel. Also using the reception function of the wireless remote control provided in the TV receiver 4, the wire Ya-less remote control transmitter for controlling the signal from the transmission unit 16 is disposed near the TV receiver 4, idle channel using the wireless remote control transmitter May be specified. Further, if the TV receiver 4 has a control terminal of each company standard used when constructing an AV system or the like, it may be used.

In the above example, the TV receiver 4 switches the receiving channel to a predetermined vacant channel. However, in the present embodiment, the TV receiver 4 is used for a TV receiver 4 having a PIP function. As shown in FIG.
Information to be transmitted to the receiver 4 via the transmission unit 16 is P
The TV receiver 4 is composed of the information of the IP screen display and the information of the channel to be used, and the TV receiver 4 transmits the information to the outside of the TV camera 6 using the available channel based on the transmitted information.
The channel of the TV signal composed of parts video signal, and received with the currently viewed channel, the screen of the channel being viewed, to PIP screen displaying video of the TV camera 6 Turkey
Door can be.

[0013] In addition to transmitting images picked up by the TV camera 6 of the slave unit 8a of the door phone, it also includes characters, pictures, symbols, and the like .
As can also be transmitted image of supermarkets Imposed
It was done . That is, as a circuit configuration in the head end 3, as shown in FIG. 5, an image generation circuit 17 for generating an image of information such as characters, pictures, and symbols, and the image generation circuit 1
7, a modulation circuit 18 for modulating the video signal obtained at 7 with the carrier frequency of the channel specified by the CPU 14, and a TV signal output from a modulation circuit 13 that modulates an external video signal from the TV camera 6; , Modulation circuit 1
A mixing circuit 15 for transmitting the TV signal output from the antenna 8 and the TV signal received from the broadcast receiving antenna 1 to the coaxial cable 2 is provided.

Then, as shown in FIG. 6, the CPU 14
There determines the channel carrier frequencies for modulating the image signal Sue generated by the channel and the image generating circuit 17 of the carrier frequency <br/> path over imposing modulating the external video signal from the TV camera 6, the corresponding To the modulation circuits 13 and 18 to perform modulation of the video signal and the image signal at the carrier frequency corresponding to the determined channel. Incidentally predetermined super instructs the selection and generation of super over <br/> superimpose images for this time CPU14 image generation circuit 17
To generate an image signal of the over-imposing.

The T consisting of an external video signal from the TV camera 6 obtained by being modulated by the respective modulation circuits 13 and 18
TV made from the image signal of the V signal and super over-imposed
The signal is transmitted over the coaxial cable 2 via the mixing circuit 15 on a predetermined channel. At the same time, the CPU 4 sends the information of the PIP screen display and the information of the used channel to the TV receiver 4 via the transmission unit 16 and the data transmission line 10.

The TV receiver 4 capable of displaying a PIP screen displays an external signal from the TV camera 6 based on the given information.
The TV signal corresponding to the image signal of the TV signal and super over-imposed corresponding to the video signal by each receiving, and video captured by the TV camera 6 in the channel screen currently being viewed, the image of the super over-imposed Display the PIP screen.
As described above, in the example of FIG. 6, if there is an incoming call at the slave 8 a of the intercom by the PIP screen display on the TV receiver 4, the image captured by the TV camera 6 can be displayed on the PIP screen display, and , painting, by super over in pose of symbols and the like can be displayed the information of the number of the intercom.

As described above, in the example of FIG. 6, in the TV receiver 4 connected to the TV signal transmission system, the image of the TV camera 6 provided on the slave unit 8a of the intercom, the character, and the picture are displayed on the PIP screen. it is obtained by so as to display an image of the super over-imposed symbols like. The present invention, which was based on the example above, the channel, as follows currently viewed, by superimposing on the entire screen, TV camera if any incoming call handset 8a of de Ahon The video captured in step 6 can be reliably presented.

[0018] Although the circuit blocks in the embodiment of the present invention is the same as FIG. 5, when the input image transmission super over-imposed by the TV receiver 4 side, the data transmission line 10 from the TV receiver 4 side ' in which differs from the embodiment in that a function which is adapted to transmit channel information and super over-in information of the pause request being viewed in transmission unit 16 of the head end 3 through.

[0019] That is, when channel information and super over-in information of the pause request during watching, as shown in FIG. 7 is transmitted thereto, CPU 14 is a super over <br/> superimpose the image on the image generating circuit 17 Instruct selection and generation. The image generation circuit 17 based on this instruction and generates the image signal of the super over-imposed. The CPU 14 instructs the modulation circuit 18 on the channel to be used based on the currently viewed channel information. The modulation circuit 18 modulates the image signal generated by the image generation circuit 17 at a carrier frequency corresponding to the specified channel. To the coaxial cable 2 via the mixing circuit 15.

The TV receiver 4 is now for the image signal of the super over-imposed at a carrier frequency corresponding to the channel currently being viewed to come is transmitted, the image of the super over Lee <br/> Npozu full screen receives this Will be displayed. Or TV camera 6
As a method of detecting the incoming of the external video signal, a method of detecting the incoming by detecting the presence or absence of the video signal may be used other than the method of using the incoming signal S of the intercom.

The TV camera 6 is a slave unit 8 of a door phone.
a, but a security TV monitor
An external video signal to be transmitted may be a camera, and is not particularly limited to the embodiment.

[0022]

[Effect of the Invention] The invention of claim 1, wherein includes a TV transmission system for transmitting TV signals through a coaxial cable, or TV camera
Together and a system for transmitting the external video signal al, super generated in the external video signal and an image generating means at a carrier frequency of a predetermined channel when the input of the external video signal
-Modulate both the imposed image and the TV signal
A head end having a mixing means for transmitting the signal via a V transmission system coaxial cable; and a means for receiving data of a current viewing channel from a TV receiver provided at the head end. Set the above external video signal and the superimposed image
Because preparative To screen displayed on the TV receiver of the aforementioned commercial TV receiver which is connected to a TV signal transmission system of the coaxial cable
There is an effect that the video of the external video signal can be projected on the TV receiver without causing screen disturbance due to switching of the received signal.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram of a basic example of the present invention.

2 is a configuration diagram of a video signal transmission device.

FIG. 3 is a flowchart for explaining the operation of the example of FIG. 1;

FIG. 4 is a flowchart for explaining the operation of another basic example of the present invention.

FIG. 5 is a circuit block diagram of another basic example of the present invention and an embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of another example of the present invention.

FIG. 7 is a flowchart for explaining the operation of the embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Broadcast reception antenna 2 Coaxial cable 3 Headend 4 TV receiver 5 Splitter 6 TV camera 8a Slave device 11 Empty channel search circuit 13 Modulation circuit 14 CPU 15 Mixing circuit 16 Transmission unit 17 Image generation circuit 18 Modulation circuit S Incoming signal

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Miyuki Oshinda 1048 Kadoma Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Works, Ltd. ) Inventor Naoko Fujiwara 1048 Kadoma, Kazuma, Osaka Prefecture Matsushita Electric Works, Ltd. (56) References JP-A-60-69995 (JP, A) JP-A-61-52086 (JP, A) JP-A-1- 200887 (JP, A) JP-A-55-93382 (JP, A) JP-A-4-53380 (JP, U)

Claims (1)

(57) [Claims] 1. A TV signal and the TV transmission system for transmitting via a coaxial cable, with and a system for transmitting the external video signal from the TV camera, at a carrier frequency of a predetermined channel when the input of the external video signal the external video signal and an image
A head end having mixing means for modulating the superimposed image generated by the generating means together with the superimposed image and transmitting the modulated signal as a TV signal via the coaxial cable of the TV transmission system; Means for receiving data of the current viewing channel from the external video signal by setting the predetermined channel as the current viewing channel.
Video signal transmission apparatus characterized by that the screen displaying the above superimposition image on the TV receiver.