JPH0759081B2 - Image transmission equipment - Google Patents

Description

TECHNICAL FIELD The present invention relates to an image transmission device used for image information transmission such as remote monitoring.

[Conventional technology]

Conventionally, there is a device shown in FIG. 4 as this type of device.
In the figure, 1 is a camera for inputting an image, 2 is a transmission unit, 3 is a sync separation section, 4 is an A / D conversion section for digitizing an analog image signal, and 6a is one screen. An image storage unit (hereinafter, referred to as a frame memory) that temporarily stores digital image information (hereinafter, referred to as image information), 7 is a sending unit that sends the image information, 5
Is a transmission controller that controls the timing of the transmission unit.

8 is a receiving unit, and in the unit 8,
Reference numeral 9 is a receiving unit for receiving the transmitted image information, and 6b is 1
A frame memory that stores image information for the screen, 11 a synchronization generator that generates a synchronization signal for display, 12 a D / A converter that converts a digital image signal into an analog signal, and 10 controls the timing of the receiving unit 8. It is a reception control unit. 13
Is a display device (hereinafter referred to as a monitor), and 14 is a transmission line.

Next, the operation will be described. In FIG. 4, the transmission unit 2 and the reception unit 8 installed with an appropriate distance are connected by a transmission line 14, and the composite video signal input from the camera 1 is converted into an analog image in the sync separation unit 3 of the transmission unit 2. Information and a sync signal composed of three signals of a horizontal sync signal, a vertical sync signal and a clock are separated. Of these, the analog image information is digitized by the clock output of the sync separation unit 3 in the A / D conversion unit 4, and the sync signal is sent to the A / D conversion unit 4 and the transmission control unit 5 at the same time. The control unit 5 stores the digital image information output from the A / D conversion unit 4 in the frame memory 6a according to the synchronization signal. At this time, the frame memory
Digital image information for one screen is stored in 6a.

In this way, when all the digital image information for one screen has been stored in the frame memory 6a, the sending unit 7 addresses the digital image information for one screen in the frame memory 6a according to the instruction from the transmission control unit 5. The data is sequentially sent to the transmission line 14 every time.

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

Receiving the image information, the reception control unit 10 sequentially stores the image information for one screen in each address of the frame memory 6b.

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

The information transmitted via the transmission line 14 is shown in FIG.

[Problems to be solved by the invention]

Since the conventional image transmission device is configured as described above, a large amount of unnecessary information is included in the image information for one screen to be transmitted, and a huge amount of information is transmitted as a whole. However, there is a problem that the transmission cost becomes long and the transmission cost becomes high.

The present invention has been made to solve the above problems, and an image transmission apparatus capable of transmitting image information of an area requiring transmission in a short time and at low cost when the information is required. Aim to get.

[Means for solving problems]

The image transmission apparatus according to the present invention reads the image information, digitizes the image information, and when there is a change in all the image information, the position, shape, size, and interval of the transmission area (hereinafter referred to as a window) including the changed area. A window control circuit that controls the lead rate and automatically determines the above window,
A window memory for storing the image information in the window, an image processing circuit for processing the image information stored in the window memory, shape information indicating the shape of the window, position information indicating the position, and a size indicating the size. information,
A transmission circuit for transmitting as transmission information together with window information composed of any one of gradation information indicating gradation and thinning information indicating thinning rate, or any combination thereof, the image processing circuit, and the transmission circuit And a transmission control circuit for controlling and.

[Action]

According to the present invention, with the configuration as described above, it is possible to obtain an image transmission device that can transmit only an area including a changed portion of image information for one screen, and that has a short transmission time and a low transmission cost. To be

〔Example〕

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

FIG. 1 shows a configuration of a transmission side of an image transmission apparatus according to an embodiment of the present invention. In the figure, 1 is a camera as an image input unit, 20 is a transmission unit, and in the unit 20,
Reference numeral 3 denotes a sync separation circuit that separates a video signal input from the camera 1 into analog image information and a sync signal. Reference numeral 4 denotes an A / D conversion that converts the analog image information into digital image information (hereinafter simply referred to as image information). Reference numeral 21a is a window control circuit for generating a write signal of the window memory according to the window information to control the position, shape, size, thinning rate and gradation of the window, and 22a is a window for temporarily storing the image information in the window. The memory 23 is transmission information obtained by adding window information such as window position information, shape information, size information, thinning information, gradation information to the image information in the window memory as a digital signal,
Alternatively, a sending circuit for converting to an appropriate signal form such as an analog signal and sending it, 24 is a transmission control circuit for controlling the timing of the sending unit and giving window information to the window control section 21a, 25 is an instruction from the sending control circuit 24 Is an image processing circuit for processing the image information stored in the window memory 22.

FIG. 2 shows the configuration of the receiving side of the image transmitting apparatus according to the embodiment of the present invention. In the figure, 30 is a receiving unit, and in the unit 30, 26 has been transmitted via the transmission line 14. An information separation unit 22b for separating the image information and the window information after converting the transmission information into a digital signal.
Is a window memory for temporarily storing the separated image information, 21b is a window control unit for generating a write signal for the window memory 22b based on the window information, and 11 is a synchronizing signal for displaying the image information in the window memory 22b on a monitor. , A D / A converter for converting digital image information existing in the window memory 22b of the receiving unit 30 into analog image information, 2
Reference numeral 7 is a reception control unit that controls the timing of the reception unit 30 and gives window information to the window control unit. 13 is a monitor as a display device, 14
Is a transmission line.

Next, the operation will be described. In FIG. 1, the camera 1
The composite video signal input from is separated by the sync separation circuit 3 into analog image information and a sync signal (hereinafter referred to as SYNC) which is composed of three signals of a horizontal sync signal, a vertical sync signal and a clock, The clock of SYNC is sent to the A / D conversion circuit 4, while the SYNC is sent to the window control circuit 21a.

The window control circuit 21a includes window information (position information, shape information, size information,
A window signal is generated by thinning information, gradation information) and SYNC.

In the A / D conversion circuit 4, the analog image information is digitized and sequentially sent to the window memory 22a for one screen.

The window memory 22a stores only the image information in the window based on the window signal sent from the window control circuit 21a among the one screen of image information sent from the A / D conversion circuit 4. However, the window signal mentioned here is a signal indicating a relatively large area set in an area where a change is likely to occur.

When the 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, the position and size of the change area are measured by, for example, fillet diameter measurement generally used in image processing, and a new window including the change area is determined based on the measurement result. , And sends the new window information and the transmission start command to the sending circuit 23. The sending circuit 23 sends the transmission information to which the new window information and the image information in the new window are added, for example, in the configuration shown in FIG. 3 (b).

On the other hand, in the receiving unit 30, when the transmission information is sent, the information separation unit 26 receives the transmission information and notifies the reception control unit 27 that the transmission information has arrived, and at the same time converts the transmission signal information into a digital signal. The image information and the window information are separated and the window information is sent to the reception control unit 27 and the image information is sent to the window memory 22b. As a result, the window information is given to the window control unit 21b via the reception control unit 27, and the window memory 22b stores the image information based on the signal from the window control unit 21b. When the storage of the image information in the window memory 22b is completed, the reception control unit 27 sends the window information to the window control unit 21b, and the window control unit 21b sends the SYN sent from the synchronization generation unit 11.
A window signal is generated by C, and window memory 2
D / A converter 12 synchronizing the image information in 2 with the window signal
Send to.

The image information sent from the D / A converter 12 is transferred to the reception controller 2
The gradation information from 7 and the clock from the synchronization generator 11 are converted into analog image information, and the analog image information is sent to the monitor 13 for display together with the sync signal. In this embodiment, the transmission information transmitted through the transmission line 14 is configured as shown in FIG. 3 (b), for example.

In the above embodiment, the D / A converter 12, the synchronization generator 11, and the window controller 21b are incorporated in the receiving unit 30 so that they can be displayed on the monitor 13. When image processing the transmission information by connecting a processing device, etc., the D / A conversion unit 12, the synchronization generation unit 11,
The window control unit 21b may be removed and the external device may directly access the window memory 22b.

In the above embodiment, only the changed area of the image is transmitted, but when there is no change in the image, the whole screen is thinned out at a thinning rate of a predetermined range of 1/4 to 1/36 and is transmitted as a rough image. You may do it.

Further, in the above-described embodiment, the configuration including one window memory, one window control circuit, and one image processing circuit is shown, but of course, a plurality of these may be provided.

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

〔The invention's effect〕

As described above, according to the image transmission device of the present invention,
When the image information is read and digitized, and all image information changes, the position, shape, size, and thinning rate of the transmission area (hereinafter referred to as window) including the changed area are controlled to automatically determine the above window. A window control circuit, a window memory for storing image information in the window, an image processing circuit for processing the image information stored in the window memory, shape information indicating the shape of the window, position information indicating the position A transmission circuit for transmitting as transmission information together with window information formed of any one of size information indicating size, gradation information indicating gradation, and thinning information indicating thinning rate, or any combination thereof. Since the transmission control circuit for controlling the image processing circuit and the transmission circuit is provided, one screen worth Only region encompassing a portion change of the image information can be transmission, short transmission time, transmission costs are low, and to make decisions in the transmission area automatically,
It shows how many frames one frame can be transmitted when transmitting consecutive frames in real time, and when all the frames can be transmitted without omission, the value is the highest, and the more frames that omission occurs, the smaller the value. The image transmission device having a high frame density can be obtained.

[Brief description of drawings]

1 and 2 are diagrams showing a configuration of an image transmission apparatus according to an embodiment of the present invention, FIG. 3 is a diagram showing a format of information to be transmitted, and FIG. 4 is a diagram showing a conventional image transmission apparatus. Is. In the figure, 1 is a camera, 2 is a transmission unit, 3 is a sync 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. Section, 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 transmission circuit, and 24 is a transmission. It is a control circuit.

Claims (4)

[Claims] 1. When a change occurs in all image information obtained by reading image information and digitizing the image information, the position, shape, size and thinning rate of a transmission area (hereinafter referred to as a window) including the changed area are controlled. A window control circuit for automatically determining the window, a window memory for storing image information in the window, an image processing circuit for processing the image information stored in the window memory, shape information indicating the shape of the window, Position information indicating the position, size information indicating the size, gradation information indicating the gradation,
A transmission circuit for transmitting as transmission information together with window information consisting of any one of the thinning information indicating the thinning rate or any combination thereof, and a transmission control circuit for controlling the image processing circuit and the transmission circuit. An image transmission device comprising: 2. The image transmission device according to claim 1, wherein a plurality of the window memories, window control circuits, and image processing circuits are provided. 3. The image transmission device according to claim 1, wherein the transmission circuit transmits the image data in order from the most significant bit of each pixel as a transmission procedure of the image data. 4. The transmission control circuit thins out the whole image at a thinning rate within a predetermined range when a change in the image is not transmitted, and transmits it as a rough image, and when a change in the image is detected, the image of the change area is detected. The image transmission device according to any one of claims 1 to 3, wherein the information is transmitted as an image having a higher resolution.