JPH03178288A - Still picture television telephone set for remote monitor - Google Patents

Abstract

PURPOSE:To reduce the operating time of a telephone line and to attain the use of the line efficiently by comparing two patterns picked up at a prescribed time interval and dialing a supervisor automatically to send the picture when a considerable difference is found. CONSTITUTION:A picture taken by a television camera 15 is quantized by an image controller 14, stored in picture memories 1, 20a and a changeover switch 21 is thrown to the position of picture memories 2, 20b for a prescribed time. On the other hand, a comparator 22 compares the contents of the picture memories 1, 2, 20a, 20b and when there is a difference of a prescribed value or over, is is informed to a CPU 11. The CPU 11 receiving the notice commands dialing to an automatic dial circuit 23 via an input output port 10. An automatic dial circuit 23 gives dialing to the stored destination in advance and sends a picture in a predetermined procedure in the talking state. Thus, when a difference is recognized in the picture, dialing is given to a supervisor to send the picture thereby attaining efficient use of line.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention modulates a still image signal captured by a camera into an audio band signal and sends it to a telephone line, and also modulates a still image signal captured by a camera and transmits it to a telephone line. This invention relates to a still image video telephone device for remote monitoring that demodulates and displays images on a display device to monitor conditions at a remote location.

[Prior Art] Recently, there has been a strong demand for videophones that can simultaneously transmit audio and images using telephone lines, and proposals have been made to use them for the purpose of monitoring conditions in remote areas. .

With current telephone lines, it is practically difficult to continuously send and receive dynamic images that require a huge amount of data, so a still image videophone device that sends still images to the other party during a call has been put into practical use. ing.

This still image videophone device temporarily interrupts a normal voice call and sends a desired still image, such as the speaker's face, a photo screen, or a picture depending on the content of the call. It is possible.

According to such a still image videophone device, it is possible to send and receive images over a telephone line, which was previously impossible, and since only one still image is sent each time, the amount of data processing does not become too large. This had the advantage that it was easy to put the videophone device into practical use.

A video telephone device capable of transmitting still images in this manner is disclosed, for example, in the October 1986 issue of Foreign Communication Technology. FIG. 3 is a circuit configuration diagram of a monochrome simple still image video phone that is one of such video phone devices.

In the figure, (1) is the handset, (2) is the microphone, (3) is the speaker, (4) is the audio input/output circuit, and (5)
is an analog circuit, (6) is a matrix switch, (7
) is a telephone interface (I/F) circuit, (8) is a telephone line connection terminal, (9) is a keypad for instructing image transmission, etc., (10) is an input/output port, and (11) is a CPU.

, (12) is a program memory, (13) is a modulation/demodulation circuit, (14) is an image controller, (15) is a television camera, (16) is an image memory, and (17) is a display.

Next, the operation of audio and image signal transmission in the conventional video telephone device will be explained with reference to FIG. In the figure, voice calls are made using the handset (1) or the microphone (2).
) to audio input/output circuit (4), analog circuit (5), matrix switch (6), telephone interface circuit (
7), and the call from the other party follows the reverse route and is reproduced on the handset (1) or speaker (3).

On the other hand, when transmitting an image signal, an ID code is sent to confirm whether the other party is a videophone with the same data format, and after confirming that the other party has returned the ID code, the image data is transmitted. I do. In other words, in the figure, when an instruction to send an image is given using the keypad (9), the CPU (11) detects this via the input/output board (10) and reads the ID code according to the program stored in advance in the program memory (12). Modulation/demodulation circuit (1
3).

The ID code from the communication partner reaches CPIJ (11) via a path opposite to the above signal path, and the code is verified. During this time, the images captured by the television camera (15) are quantized by the image controller (14), stored in the image memory (16), and sequentially derived and displayed on the display (17). In addition, CPU (11
) The image data read out from the image memory (16) is amplitude-phase modulated by the modulation/demodulation circuit (13) and output to the telephone line connection terminal (8).

On the other hand, when an ID code or image data is input from the other party, the matrix switch (6) changes the destination of the received signal from the telephone interface circuit (7) from the analog circuit (5) to the modulation/demodulation circuit according to the received carrier signal. Switch to (13). After demodulating the received signal in the modulation/demodulation circuit (13), the CPU (11)
The code is returned or the data is stored in the image memory (16), and the image controller (14) sequentially derives the self-portrait data and the other party's image data and displays them on the display (17).

Note that when the transmission and reception of images is completed and the carrier signal from the modulation/demodulation circuit (13) disappears, the matrix switch (
6) is a telephone interface circuit (7) and an analog circuit (
5) to restore voice communication.

[Problems to be Solved by the Invention] Conventional still image video telephone devices for remote monitoring have the above-mentioned configuration, so in order to constantly monitor the situation at a remote location, it is necessary to keep the telephone line open at all times. However, there was a problem in that the telephone line usage charges would be enormous.

Another problem is that it takes about 10 seconds to transmit one image, and during that time the images from the television camera cannot be monitored. Therefore, there is a problem that the above problems must be solved.

Purpose of the Invention This invention was made in view of the above-mentioned problems, and includes a system that calls a supervisor and sends the image when there is a change in a still image taken with a camera, and continuously monitors the image even while the image is being sent. An object of the present invention is to obtain a still image videophone device for remote monitoring that can store monitoring images in an image memory.

[Means for Solving the Problems] A still image videophone device for remote monitoring according to the present invention includes an image memory that stores images for a plurality of screens, and a still image taken by a camera that displays the images at predetermined time intervals. The image processing apparatus includes means for sequentially storing data in a memory, and a comparator for comparing the contents of the image memory and detecting whether there is a difference. If a difference is found in the images as a result of the comparison by the comparator, the system is equipped with means for automatically dialing a pre-stored telephone number and transmitting the images once the line is connected.

[Operation] The still image videophone device according to the present invention compares still images sequentially stored in the image memory for multiple screens at predetermined time intervals, dials a supervisor if a difference is found in the images, and Since the image is transmitted, the time required to use the telephone line can be shortened, and the line can be used efficiently.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings. 1st
FIG. 1 is a block diagram showing an embodiment of a still image videophone device for remote monitoring according to the present invention. In the figure, the handset (1), microphone (2), speaker (3), audio input/output circuit (4), analog circuit (5), matrix switch (6), telephone interface (1/F) circuit (7) , telephone line connection terminal (8), keypad (9),
The configuration of the human output port (10), CPU (11), program memory (12), modem circuit (13), image controller (14), television camera (15), and display (17) is shown in Figure 3. Since it is similar to the conventional one, detailed explanation will be omitted.

(20) has multiple memories, in this example, four memories, and memory 1 so that images for multiple screens can be stored.
(20a), memory 2 (20b), memory 3 (20c)
, memory 4 (20d), and its input terminal is connected via a changeover switch (21) for alternately switching and connecting the image memory (20) for multiple screens to the image controller (14). The output side is connected to an image controller (14), and the output side is connected to a comparator (22) for comparing the contents of two of the image memories (20) for a plurality of screens.

The output of the comparator (22) is connected to the CPU (11). (23) is an automatic dialing circuit that automatically dials a telephone light stored in advance, and is connected to the matrix switch (6) and the telephone line connection terminal (8). FIG. 2 is a block diagram showing an example of the configuration of the comparator (22).

(31) is a switch for selecting any two of the plurality of image memories (2G), and a subtractor (31) that takes the difference for each pixel between the contents of the two image memories (20) 32), an absolute value circuit (33), a summation circuit (34) which calculates the sum of the above-mentioned differences for one screen, and a determiner (35) which judges whether the sum exceeds a certain predetermined threshold value. It is connected.

Next, the operation will be explained. In FIG. 1, it is assumed that the changeover switch (21) connects the image memory 1 (20a) and the image controller (14).

The image captured by the television camera (15) is quantized by the image controller (14) and stored in image memory 1 (20a).
is stored in

After a certain period of time, the changeover switch (21) is switched to the image memory 2 (20b) side, and the image captured by the television camera (15) at this time is stored in the image memory 2 (20b). After a certain period of time, switch (21)
) is again switched to the image memory 1 (20a) side, and the image is stored in the image memory 1 (20a). This operation is repeated thereafter.

On the other hand, in the comparator (22), the image memories 1 and 2
The contents of (20a, 20b) are compared, and if there is a difference greater than a certain value, the CPU (11) is notified. That is, in FIG. 2, the switch (31) is connected to the memory 1 (20
a) and memory 2 (20b), the subtracter (32) takes the difference between the contents of the two memories in pixel units, and the absolute value circuit (33) converts the difference into an absolute value. , a summation circuit (34) calculates the sum for one screen, and a judge (35) checks whether the summation result reaches a certain threshold, and if it does, the CP
Inform U (11) of this.

The CPU (11) that received the notification connects the input/output port (1
0) to instruct the automatic dialing circuit (23) to dial. The automatic dialing circuit (23) dials a pre-stored telephone light, and when a call is established, transmits an image according to a predetermined procedure.

When the image transmission state is entered, the changeover switch (21) is switched to the image memory 3 (20c) side, and the image captured by the television camera (15) is transferred to the image memory 3 (20c).
C). Next, the changeover switch (21) is switched to the image memory 4 (20d) side, and the image is stored in the image memory 4 (20d). The comparator (22) uses the above procedure to compare the contents of memory 3 (20c) and memory 4 (20
Compare with the contents of d). In other words, in Figure 2,
When the switch (31) is switched to the image memory 3 (20c) and image memory 4 (20d) sides and a difference is detected by the above procedure, the image is transmitted after waiting for the end of the image transmission that was previously transmitted. When the transmission of the previous image is completed, the current image is transmitted and the switch (31) is switched to the memory 1 (20a) side, and the above procedure is repeated thereafter.

In the above embodiment, the image transmitted to the supervisor is one screen of the compared image memories, but it is also possible to extract or enlarge only the part that has changed and transmit it. .

Further, in the above embodiment, when an image change is detected, the image is transmitted to the supervisor, but a function may be added to generate an alarm on the supervisor side.

Further, in the above embodiment, the case where the image memory is for four screens has been described, but the memory may be for five or more screens.

[Effects of the Invention] As explained above, the present invention is capable of automatically dialing and transmitting images to a supervisor when two images taken at regular time intervals are compared and a difference is found. In addition, since the system is configured so that image capturing and comparison can be performed at all times even during image transmission, the telephone line usage time can be shortened and the line can be used efficiently.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of a still image video telephone device for remote monitoring according to the present invention, FIG. 2 is a block diagram showing a detailed configuration of the comparator shown in FIG. 1, and FIG. FIG. 2 is a block diagram showing the configuration of a still image videophone device. In the figure, (11) is a UPU, (20) is an image memory, (22) is a comparator, and (23) is an automatic dial circuit. Note that the same symbols in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] A still image signal taken by a camera is modulated into an audio band signal and sent to a telephone line, and the still image signal supplied from the telephone line is demodulated and displayed as an image on a display device to be transmitted remotely. A still image videophone device for remote monitoring for monitoring ground conditions, comprising: an image memory for storing images for a plurality of screens; and means for sequentially storing still images taken by the camera in the image memory at predetermined time intervals. , a comparator that compares the contents of the images sequentially stored in the image memory and detects whether there is a difference; 1. A still image video telephone device for remote monitoring, comprising means for automatically dialing a number and transmitting an image in which the difference is detected when a line is connected.