JPS61252784A - Picture transmitter - Google Patents

Abstract

PURPOSE:To transmit the picture information of an area required for the transmission in a short time and at a low cost by providing the picture processing circuit to detect a change of a picture plane and extracting and transmitting only a change area when the change is produced in the picture plane. CONSTITUTION:A window control circuit 21 generates a window signal by the window information from a transmission control circuit 24 and a synchronous signal SYNC. In an A/C converting circuit 4, an analog picture information is digitized and 1 picture plane thereof is transmitted successively to a window memory 22a. The window memory 22a sores only the picture information in a window based on a window signal fed from the window control circuit 21a of the 1 picture plane of the picture information fed from the A/D converting circuit 4. When the picture information is completed to be stored, the transmission control circuit 24 issues a picture processing command for detecting a change to a picture processing circuit 25. If there is a change, the window information and a transmission start command are transmitted to a transmission circuit 23 and in the transmission circuit 23, the transmission information to which the window information and the picture information are added is transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image transmission device used for transmitting image information such as remote monitoring.

[Conventional technology]

Conventionally, there was a device of this type as shown in Figure 4.
In the figure, 1 is a camera for inputting images, 2 is a transmitting unit, in the unit 2, 3 is a synchronization separation section, 4 is an A/D conversion section for digitizing analog image signals, and 6a is for one screen. An image storage section (hereinafter referred to as a frame memory) that temporarily stores digital image information (hereinafter referred to as image information); 7 is a transmission section that transmits the image information; 5 is a transmission control section that controls the timing of the transmission unit. .

Further, 8 is a receiving unit, and in this unit 8,
Reference numeral 9 indicates a receiving unit that receives the transmitted image information, 6b indicates a frame memory that stores image information for one screen, 11 indicates a synchronization generating unit that generates a synchronization signal for display, and 12 indicates an analog converter for converting digital image signals. 10 is a reception control unit that controls the timing of the reception unit 8. Note that 13 is a display device (hereinafter referred to as a monitor), 14
is the transmission line.

Next, the operation will be explained. In FIG. 4, the transmitting unit 2 and the receiving unit 8, which are installed at an appropriate distance, are connected by a transmission line 14, and the composite video signal input from the camera 1 is sent to the synchronization separation unit 3 of the transmitting unit 2 as an analog image. It is separated into information and a synchronization signal consisting of three signals: a horizontal synchronization signal, a vertical synchronization signal, and a clock.

Among these, the analog image information is processed in the A/D converter 4.
It is digitized by the clock output of the synchronization separation section 3, and the synchronization signal is sent to the A/D conversion section 4 and at the same time to the transmission control section 5, and the transmission control section 5 performs the A/D conversion according to the synchronization signal. The digital image information output from the unit 4 is stored in the frame memory 6. At this time, digital image information for one screen is stored in the frame memory 6.

When all the digital image information for one screen has been stored in the frame memory 6 in this way, the sending unit 7 sends the digital image information for one screen in the frame memory 6 to the address according to the command from the transmission control unit 5. The data is sent to the transmission line 14 sequentially.

In the receiving unit 8, the receiving section 9 receives the image information transmitted via the transmitting section 14, and notifies the receiving control section 10 that the image information has arrived.

Upon learning that the image information has arrived, the reception control unit 10
Image information for a screen is sequentially stored in each address of the frame memory 6.

Then, when the storage of image information for one screen is completed, the reception control section 10 sends the image information in the frame memory 6 to the D/A conversion section 12 in accordance with the synchronization signal from the synchronization generation section 11, and converts the image information to the D/A conversion section 12. A section 12 converts the image information into an analog signal and sends it together with a synchronizing signal to a monitor 13 for display.

Note that information transmitted via the transmission line 14 is shown in FIG. 3 (111).

[Problem that the invention seeks to solve]

Since conventional image transmission devices are configured as described above, there is a lot of unnecessary information in the image information for one screen to be transmitted (
This results in the transmission of a huge amount of information, leading to problems such as longer transmission times and higher transmission costs.

This invention was made to solve the above-mentioned problems, and provides an image transmission device that can transmit image information of an area that requires transmission at a time when that information is needed in a short time and at low cost. The purpose is to obtain.

[Means for solving problems]

The image transmission device according to the present invention is provided with an image processing circuit to detect a change in the screen, and when a change occurs in the screen, only the changed area is extracted and transmitted.

[Effect]

In this invention, the image processing circuit detects the presence or absence of a change in the image, and the window control circuit extracts only the image information in the area where the change occurred from among the image information for one screen, and extracts the image information in the changed area. Since window information for controlling the changed area is added to the image and sent, only information on the changed area is transmitted to the receiving unit only when a change occurs in the image on the transmitting side.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the transmitting side of an image transmitting apparatus according to an embodiment of the present invention. In the figure, 1 is a camera which is a video input section, 20 is a transmitting unit, and in the unit 20, 3 is a camera 1. 4 is an A/D conversion circuit that converts the analog image information into digital image information (hereinafter simply referred to as image information); 21 is an A/D conversion circuit that separates the video signal input from 22a is a window control circuit that generates a write signal for a window memory according to window information and controls the position, shape, size, thinning rate, and gradation of the window; 22a is a window memory that temporarily stores image information within the window;
3 transmits transmission information in which window information such as window position information, shape information, size information, thinning information, and gradation information is added to the image information in the window memory as a digital signal or as an analog signal. 24 is a transmission control circuit that controls the timing of the transmission unit and also provides window information to the window control unit 21; 25 is a transmission control circuit that converts the signal into a signal format and sends it out;
This is an image processing circuit that processes image information stored in 2.

Further, FIG. 2 shows the configuration of the receiving side of the image transmission apparatus according to an embodiment of the present invention. An information separation unit that converts transmission information into a digital signal and then separates it into image information and window information, 22b is a window memory that temporarily stores the separated image information, and 21b is a writing device for the window memory 22b based on the window information. Window control section that generates signals, 11 is window memo 1722 b
12 is a D/A converter that converts digital image information existing in the window memory 22b of the receiving unit 30 into analog image information; 27 is a receiving unit; unit 3
This is a reception control section that performs timing control of 0 and provides window information to the window control section.

Note that 13 is a monitor as a display device, and 14 is a transmission line.

Next, the operation will be explained. In Figure 1, camera 1
The input composite video signal is separated by the synchronization separation circuit 3 into analog image information, a synchronization signal (hereinafter referred to as 5YNC) consisting of three signals: a horizontal synchronization signal, a vertical synchronization signal, and a clock. The clock of 5YNC is sent to the A/D conversion circuit 4, while only 5YNC is sent to the window control circuit 21.

The window control circuit 21 receives window information (position information, shape information, size information, etc.) from the transmission control circuit.
(thinning information, gradation information) and 5YNC to generate a window signal.

The A/D conversion circuit 4 digitizes the analog image information and sequentially sends it to the window memory 22a for one screen.

The window memory 22a stores only the image information within the window based on the window signal sent from the window control circuit 21a, out of the image information for one screen sent from the A/D conversion circuit 4.

When storage of the image information is completed, the transmission control circuit 24 issues an image processing command for change detection to the image processing circuit 25. If there is a change, it sends window information and a transmission start command to the sending circuit 23. The transmission circuit 23 transmits transmission information to which window information and image information are added, for example, in a configuration as shown in FIG.

On the other hand, in the receiving unit 30, when the transmission information is sent, the information separation section 26 receives it and notifies the reception control section 27 that the transmission information has arrived, and at the same time converts the transmission signal information into a digital signal. It separates the image information and window information and sends the window information to the reception control section 27 and the image information to the window memory 22b, respectively. As a result, the above window information is given to the window control section 21b via the reception control section 27, and the window memory 22b stores the above image information based on the signal from the window control section 21b. When the image information has been stored in the window memory 22b, the reception control section 27 sends the window information to the window control section 21b, and the window control section 21b generates a window signal based on the 5YNC sent from the synchronization generation section 11. Then, the image information in the window memory 22 is sent to the D/A converter 12 in synchronization with the window signal.

The D/A converter 12 converts the sent image information into analog image information using the gradation information from the reception controller 27 and the clock from the synchronization generator 11, and the analog image information is displayed on the monitor 13 together with the synchronization signal. sent to and displayed.

In this embodiment, the transmission information transmitted through the transmission line 14 is structured as shown in FIG. 3(b), for example.

In the above embodiment, the receiving unit 30 includes a D/A converter 12, a synchronization generator 11, and a window controller 21.
b is built in so that it can be displayed on the monitor 13, but when the transmitted information is processed as an image by connecting an external image processing device or the like without displaying it, the D/A converter 1
2. Synchronization generator 11. Window control section 21b
may be removed, and the external device may directly access the window memory 22b.

In addition, in the above embodiment, only the changing area of the image is transmitted, but when there is no change in the image, the entire screen is transmitted by 1/4 to 1/4
The image information may be thinned out at a predetermined thinning rate in a predetermined range of 36, and the coarse image and image information of the area may be transmitted as a higher resolution image.

Further, in the above embodiment, a configuration including one window memory, one window control circuit, and one image processing circuit was shown, but it is of course possible to provide a plurality of these.

Further, in the above embodiment, the image processing circuit, the transmission control circuit, and the sending circuit are implemented as hardware circuits, but it is also possible to use a program-controlled microcomputer to replace the above three functions.

〔Effect of the invention〕

As described above, according to the present invention, of the image information for one screen, only the image information of a necessary partial area can be retrieved when necessary.
Since the image is configured to be transmitted together with the control information of the partial area, an image transmission apparatus with short transmission time and low transmission cost can be obtained.

[Brief explanation of drawings]

1 and 2 are diagrams showing the configuration of an image transmission device according to an embodiment of the present invention, FIG. 3 is a diagram showing the format of transmitted information, and FIG. 4 is a diagram showing a conventional image transmission device. It is. In the figure, 1 is a camera, 2 is a transmitting unit, 3 is a synchronization separation unit, 4 is an A/D conversion circuit, 5 is a transmission control circuit, 6 is a frame memory, 7 is a sending unit, 8 is a receiving unit, and 9 is a receiving unit. 10 is a reception control section, 11 is a synchronization generation section, 12 is a D/A conversion section, 13 is a monitor, 14 is a transmission line, 21 is a window control circuit, 22 is a window memory,
23 is a transmitting circuit, and 24 is a transmission control circuit.

Claims (6)

[Claims] (1) A predetermined area (hereinafter referred to as a window) of all image information that has been read and digitized from image information
image information of the window, any one of shape information indicating the shape of the window, position information indicating the position, size information indicating the size, gradation information indicating the gradation, and thinning information indicating the thinning rate.
a transmission circuit that transmits the window information as transmission information together with window information consisting of one or any combination thereof; a window control circuit that controls the position, shape, size, and thinning rate of the window; and a window that stores the image information within the window. An image transmission device comprising: a memory; an image processing circuit that processes image information stored in the window memory; and a transmission control circuit that controls the image processing circuit and the transmission circuit. (2) The image transmission device according to claim 1, characterized in that a plurality of each of the window memories, window control circuits, and image processing circuits are provided. (3) The image transmission device according to claim 1 or 2, wherein the transmission circuit transmits the image data in order from the most significant bit of each pixel as a transmission procedure. (4) The image transmission device according to any one of claims 1 to 3, wherein the image processing circuit includes means for detecting a change in the image. (5) The transmission control circuit starts transmission of the image when a change in the image is detected.
The image transmission device described in . (6) When there is no change in the image, the transmission control circuit thins out the entire image at a predetermined thinning rate and transmits it as a coarse image, and when a change in the image is detected, it transmits the image information of the changed area. The image transmission device according to claim 4, wherein the image transmission device transmits the image as a higher resolution image.