JPH06105309A - Video monitoring method for catv system - Google Patents

Abstract

PURPOSE:To smoothly perform the maintenance/check of the system by converting a video, which is received in the middle of a repeating transmission line or at the subscriber house of a terminal, to a signal, returning it to a center, and performing centralized monitor and management for the video of each part of the repeating transmission line at the center. CONSTITUTION:The video signal of a designated channel is outputted from a tuner 3 provided at the suitable position of a repeating transmission line 2 connecting a center 1 and a subscriber, and the video signal is converted into image data by an image processor 4, further converted into an RF signal and returned to the center 1. This RF signal is converted into the image data at the center 1 and recorded in a memory device 7 and further, the image data read out of the memory device 7 are converted into the video signal by an image processor 8 and displayed at a receiver 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video monitoring method capable of centrally monitoring a video in the middle of a relay transmission line of a CATV system or a received image of a subscriber.

[0002]

2. Description of the Related Art A CATV system broadcasts from a center to a subscriber by a relay transmission line extending between the center and the subscriber. A coaxial cable is used for this relay transmission line, and various devices such as a relay amplifier, a distributor, and a branching device are provided therein. In order to maintain such a complicated CATV system normally and provide a good quality image to the subscriber, it is necessary to monitor and monitor the image of the channel being transmitted at each place of the relay transmission line on a daily basis. .

Therefore, conventionally, as shown in FIG. 3, an inspector has a receiver C or a spectrum analyzer for inspection at a monitor terminal of a relay transmission device B (in particular, an amplifier) located in the middle of the relay transmission line A at the time of maintenance / inspection. An image monitoring method has been adopted in which an inspector visually checks the image or signal level projected on the D by connecting it.

Conventionally, in order to check the image received by a subscriber, each subscriber receives a TV image through a terminal tuner F from a signal sent from a center E through a relay transmission line A, as shown in FIG. The image was received by the machine G and the image of the receiver G was being viewed.

[0005]

However, the above-mentioned video monitoring method has the following problems. In either inspection method, the inspector visually checked the image projected on the receiver C (G), and therefore the image quality evaluation was influenced by the inspector's subjectivity, and as a result, the quality criterion. Also tends to be ambiguous. The image projected on the receiver C (G) cannot be recorded on paper as a numerical value in detail, such as a signal level, so the evaluation is rough, and detailed evaluation is performed by an inspector. When the inspector is replaced by the memory, the past inspection results (history) will be used for subsequent inspections.
Could not be fully reflected. A large-scale CATV system requires a large number of inspectors to visit the site and inspect it, and it also takes many days to perform the inspection, which is a problem that it takes a lot of labor and time. . When inspecting at the subscriber's house H, the abnormality cannot be known at the center E unless the administrator of the CATV facility is notified of the state such as unviewable or image deterioration, and the administrator who received the notice is in a situation. There was the trouble of having to go to the subscriber's house H for confirmation.

The video monitoring method in the CATV system of the present invention enables the video received in the middle of the relay transmission line or the house of the subscriber company at the end to be converted into an RF signal and sent back to the center so that the relay transmission line can be sent to various places. It enables the centralized monitoring and management of images of
The purpose is to enable smooth inspection.

[0007]

As shown in FIG. 1, a video monitoring method in a CATV system according to claim 1 of the present invention is a tuner provided in the middle of a relay transmission line 2 connecting a center 1 and a subscriber. 3 outputs a video signal of the designated channel from the center 1, converts the video signal into image data by the image processing device 4, converts the image data into an RF signal, and sends the RF signal back to the center 1; In No. 1, the received RF signal is converted into image data, recorded in the memory device 7, and if necessary, the image data read from the memory device 7 is converted into the original video signal by the image processing device 8 and the receiver 9 is received. Is to be displayed.

According to a second aspect of the present invention, the method of monitoring a video in a CATV system is, as shown in FIG.
The tuner 3 at the subscriber's house of the system outputs a video signal of the receiving channel, the video signal is converted into image data by the image processing device 4, the image data is converted into an RF signal, and the RF signal is sent back to the center 1. In the center 1, the received RF signal is converted into image data, recorded in the memory device 7, and if necessary, the image data read from the memory device 7 is converted into an original video signal by the image processing device 8 to be received by the receiver. 9 is displayed.

According to a third aspect of the present invention, in the video monitoring method in the CATV system, when the CATV system is a bidirectional system, the RF signal of the first or second aspect is sent to the center 1 by the up line of the relay transmission line 2. It is characterized by being returned.

The video monitoring method in the CATV system according to claim 4 of the present invention is characterized in that the RF signal according to claim 1 or 2 is returned to the center 1 by a wired or wireless telephone line. Is.

[0011]

In the video monitoring method in the CATV system according to claim 1 of the present invention, the video received by the tuner 3 in the middle of the relay transmission line 2 can be displayed on the receiver 9 of the center 1 while operating the controller 10. If the image processing device 8 can perform various processes on the projected image,
It becomes possible to accurately judge the quality of the received image quality. Further, the image received by the tuner 3 is accurately recorded as data in the memory device 7, and the change in the image can be recorded as a history.

In the video monitoring method in the CATV system according to the second aspect of the present invention, the video displayed on the TV receiver 16 of the subscriber's home 12 is displayed on the receiver 9 of the center 1 while operating the controller 10. It is possible,
Moreover, if the image processing device 8 performs various processes on the projected image, it becomes possible to accurately judge the quality of the received image quality. Further, when a reception failure occurs at the subscriber's home side, it can be monitored by the center 1, and the evaluation and the cause of the communication failure can be investigated quickly. Further, the image of the tuner 3 is accurately recorded as data in the memory device 7, and the change of the image can be recorded as a history.

In the video monitoring method in the CATV system according to the third aspect of the present invention, the video to be monitored is returned to the center 1 by the upstream line of the relay transmission line 2.

In the video monitoring method in the CATV system according to the fourth aspect of the present invention, the video to be monitored is returned to the center 1 through the telephone line even if the relay transmission line 2 is not bidirectional communication.

[0015]

[Embodiment 1] FIG. 1 shows an embodiment of a video monitoring method in a CATV system according to the present invention. In the CATV system of FIG. 1, a relay transmission line 2 connecting a center 1 (head end 11) and a subscriber is unidirectional communication, and various relay transmissions such as an amplifier are provided in the middle of the relay transmission line 2. The device 15 is installed.

The relay transmission device 15 (amplifier) of the relay transmission line 2 is provided with a monitor terminal for measuring the input / output level, and the tuner 3, the image processing device 4, the modem 5, and the TV are connected to the monitor terminal. A receiver 16 and a microprocessor (μPC) 17 are attached. The tuner 3 selects and receives a desired channel from the signals sent to the amplifier 15, and receives the control signal sent from the center 1. The received image can also be viewed by the TV receiver 16. The image processing device 4 converts the video received by the tuner 3 into image data that can be handled by a computer.

The μPC 17 receives a control signal from the center and designates a channel to be received by the tuner 3, or controls the modem 5 based on the control signal to output image data output by the image processing device 4. Is input to the modem 5. Finally, the modem 5 converts the image data into an RF signal and returns the RF signal to the center 1 via a wireless telephone line.

A spectrum analyzer 18 is also installed in parallel with the tuner 3. The spectrum analyzer 18 is capable of measuring the frequency characteristic of the relay transmission line 2 and the like, and the measurement result is output as a digital signal. This digital signal is controlled by the μPC 17 and sent to the modem 5 and returned to the center 1 via the wireless telephone line.

On the other hand, in the center 1, a modem 6 which receives the RF signal returned from the modem 5 of the amplifier 15 via the radio telephone line and converts it into the original image data, and the image data are successively received. A memory device 7 for recording and an image processing device 8 for converting image data called from the memory device 7 into a video signal and displaying it on a receiver 9 are installed.

The above-mentioned device is controlled by a controller 10 having a built-in μPC, and an administrator operates the controller 10 to send a command to the memory device 7, the modem 6, and the image processing device 8 to cause the memory device 7 to operate. The desired image data can be read from the device, and various processes can be performed on the read image data to check the quality of the image displayed on the receiver 9. The controller 10 is also for generating a control signal to be sent to the μPC 17 of the amplifier 15, and the administrator operates the controller 10 to instruct the receiving channel of the tuner 3 and the returning of the received video.

[0021]

[Embodiment 2] FIG. 2 shows an embodiment of a video monitoring method in a CATV system according to the present invention. In the CATV system shown in the figure, a relay transmission line 2 connecting a center 1 (head end 11) and a subscriber's house 12 is bidirectionally communicated, and a bidirectional amplifier or the like is provided in the middle of the relay transmission line 2. Various relay transmission devices 15 are installed.

A tuner 3 and a TV receiver 16 are connected to the subscriber's house 12 at the end of the relay transmission line 2. The tuner 3 allows the viewer to select the channel and watch the program
This tuner 3 is to be displayed on the V receiver 16.
Has a spare video output terminal and a video input terminal. An image processing device 4 is connected to the video input terminal, and the video received by the tuner 3 is transferred to the modem 5 or the μPC 17 here.
Are converted into image data that can be handled by and output to the modem 5. Further, in the modem 5, the image data is R
The signal is converted into an F signal and input to the image input terminal of the tuner 3, and from there, the RF signal is sent back to the center 1 to the bidirectional relay transmission line 2. The μPC17 is used in the first embodiment.
Similarly to the above, it is for controlling the image processing device 4 and the modem 5.

On the other hand, at the head end 11 which is the starting point of the relay transmission line 2, a modem 6 for receiving the RF signal sent from the subscriber's house 12 and converting it into the original image data, and the image thereof A memory device 7 for recording and storing data and an image processing device 8 for converting the data called from the memory device 7 into an image signal and displaying the image signal on a receiver 9 are installed. These devices are controlled by the controller 10 as in the first embodiment, and the memory device 7 is operated by operating the controller 10 and sending a command by the administrator.
Check the quality of the image quality by reading out the desired image data from the device and displaying it on the receiver 9, or by causing the image processing device 8 to perform various image processing and changing the image displayed on the receiver 9. To do. It also generates a control signal to the μPC 17 of the subscriber's house 12.

[0024]

The video surveillance method in the CATV system of the present invention has the following advantages. The image to be evaluated is processed by the image processing device 8 and displayed on the image receiver 9 of the center 1. Therefore, if various processes are performed on the image received by the image processing device 8, the image quality can be evaluated more easily. Become. Since the image sent to the center 1 is sequentially and accurately recorded and stored as data in the memory device 7, the past inspection result can be sufficiently reflected in the subsequent inspection. Even in a large-scale CATV system, the relay transmission line 2
Since the images of each place are sent back to the center 1 as signals, the survey does not take much time, and the survey results are stored in the memory device 7, which makes management very easy. Particularly, in the invention of claim 2, since the receiving channel of the subscriber can be checked immediately, it can be applied to the audience rating survey.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of a video monitoring method in a CATV system of the present invention.

FIG. 2 is an explanatory diagram showing another embodiment of the video monitoring method in the CATV system of the present invention.

FIG. 3 is an explanatory diagram showing an example of a video monitoring method in a conventional CATV system.

FIG. 4 is an explanatory diagram showing another example of a video monitoring method in a conventional CATV system.

[Explanation of symbols]

 1 Center 2 Relay Transmission Line 3 Tuner 4 Image Processing Device 7 Memory Device 8 Image Processing Device 9 Image Receiver

Claims (4)

[Claims] 1. A relay transmission line 2 connecting a center 1 and a subscriber.
A video signal of a channel designated by the center 1 is output from a tuner 3 provided in the middle of the process, the video signal is converted into image data by an image processing device 4, and the image data is converted into an RF signal to be transmitted to the center 1. Then, the center 1 converts the received RF signal into image data, and the memory device 7
A video monitoring method in a CATV system, characterized in that the image data read out from the memory device 7 is converted into an original video signal by the image processing device 8 and displayed on the receiver 9 as necessary. 2. A tuner 3 in a subscriber's house of a CATV system outputs a video signal of a reception channel, the video signal is converted into image data by an image processing device 4, and this image data is converted into an RF signal to be transmitted to a center. 1, the center 1 converts the received RF signal into image data, records the image data in the memory device 7, and reads the image data read from the memory device 7 as necessary by the image processing device 8 to the original video signal. CA, which is converted into and displayed on the receiver 9.
Video monitoring method in TV system. 3. The CATV system according to claim 1 or 2, wherein when the CATV system is a bidirectional system, the RF signal is returned to the center 1 through an upstream line of the relay transmission line 2. Video surveillance method. 4. A video monitoring method in a CATV system, characterized in that the RF signal according to claim 1 or 2 is returned to the center 1 by a wired or wireless telephone line.