JPH07123131A - Picture transmission system - Google Patents

Abstract

PURPOSE:To improve the efficiency of a transmission line by enabling an information processing means to change the transmission data speed of an image pickup control means. CONSTITUTION:A controller 22 outputs the photographed picture from an image pickup device 20 to a communications line 24. An information processor 26 displays the reception picture from the communications line 24 in the picture display window on a picture display device 28. The picture display window is freely expanded and reduced by an operation member like a mouse. When the size of the picture display window is changed, the information processor 26 reports the transmission picture data volume for the size after the change to the controller 22. The controller 22 outputs the photographed picture to the communication line 24 with the transmission picture data volume according with reported information.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention transmits an image picked up by an image pickup device using a CCD area sensor or the like in real time to an information processing device such as a computer via a communication line such as LAN, ISDN and a dedicated line. , An image transmission system for displaying an image on a screen of an information processing device side.

[0002]

2. Description of the Related Art Conventionally, there are a video conference system and a video telephone as a system for transmitting an image in real time through a communication line such as a LAN, ISDN and a dedicated line. In recent years, with the progress of computer and communication technology, images,
So-called multimedia applications that use a mixture of voice and character data are also increasing.

When an image is used on such an application, a window display system is often used. That is, a window having an appropriate size is set on the monitor screen, and the transmitted image is displayed in the window. In the window display system, generally, the size of the set window can be freely changed. For example, vertical 10
A window of 0 pixels and 200 pixels horizontally can be reduced to 50 pixels vertically and 100 pixels horizontally, or enlarged to 200 pixels vertically and 400 pixels horizontally. When the captured image is displayed, it is preferable that the aspect ratio is constant even if the size is changed, and thus it is usual that the aspect ratio is restricted.

The image to be transmitted is 100 pixels vertically and 20 pixels horizontally.
A black and white image of 0 pixels, which is quantized with 8 bits per pixel, and the frame frequency is 30 Hz,
The amount of transmitted image data is 600 KByte / s. As shown in FIG. 7, when this is displayed in the image display window 10 having 100 pixels vertically and 200 pixels horizontally, the necessary and sufficient image data is transmitted, so there is no excess or deficiency. If it is reduced like the image display window 12 of 100 pixels, the required transmission image data amount is 150 KB.
yte / s and 1/4. Excessive pixels will be thinned out. On the contrary, the image display window 10 is displayed vertically 20
When it is enlarged to the image display window 14 of 0 and 4090 pixels horizontally, the required transmission image data amount is 2,400 KBytes.
/ S, which is significantly short. The insufficient pixel data to be displayed will be supplemented by interpolation or the like.

[0005]

However, in the conventional example,
Since the amount of image data output from the image pickup device to the communication line is constant regardless of the display size, the computer side is often required to perform thinning or interpolation processing. If the window size is smaller than the predetermined value, it means that the communication line is wasted. Even if the window size is made larger than a predetermined value, the resolution of the image does not improve.

It is an object of the present invention to provide an image transmission system that eliminates such inconvenience.

[0007]

An image transmission system according to the present invention transmits an image picked up by an image pickup means via a transmission line and displays it on a screen of an image display means in one of a plurality of sizes which can be freely selected. The image transmission system according to the present invention is characterized in that the transmission image data amount can be freely changed according to the display size on the screen of the image display means.

The image transmission system according to the present invention is also an image transmission system for transmitting an image picked up by an image pickup means via a transmission line and displaying the image on the screen of the image display means. It is characterized in that it corresponds to the display size on the screen of the image display means.

The image transmission system according to the present invention also transmits an image pickup means for picking up an image, an image pickup control means for controlling the image pickup means, and a transmission medium for transmitting the image picked up by the image pickup means. An image transmission system having information processing means for receiving an image, display means for displaying the image received by the information processing means, and operation means for operating the image display on the display means. The information processing means notifies the imaging control means of the amount of transmission image data corresponding to the operated image display, and the information processing means can change the transmission data rate of the imaging control means. .

[0010]

With the above means, the amount of transmitted image data always matches the size of the display screen, and the transmission medium can be used efficiently. Further, the burden of thinning and interpolation on the image display side is reduced.

[0011]

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

FIG. 1 shows a schematic block diagram of a system to which the present invention is applied. In FIG. 1, reference numeral 20 denotes an image pickup device that converts an optical image into an electric signal in real time using a CCD area sensor or the like; Is a communication line, 26 is an information processing device, such as a computer, for receiving image data transmitted via the communication line, 28 is an image display device connected to the information processing device 26, and 30 is an image display device. An operation member such as a mouse for operating the size of the window in 28.

The operation of this embodiment will be described with reference to FIG. The control device 22 initializes the image transmission data amount of the captured image by the imaging device 20 (S10), and outputs the captured image with the image transmission data amount to the communication line 24. The information processing device 26 sets the image display window for displaying the received image in the image display device 28 with the default window size (S20), and displays the image received from the communication line 24 in the image display window (S23). ).

When the size of the image display window is changed by the operation of the operation member 30 (S21), the information processing device 26 notifies the control device 22 of the transmission image data amount corresponding to the changed window size ((S21)). S22).

When the control device 22 receives the notification of the change of the transmission image data amount from the information processing device 26 (S11), the control device 22 changes the setting of the transmission image data amount (S12), and acquires the captured image data with the transmission image data amount. The information is transmitted to the information processing device 26.

Next, the operation of this embodiment will be concretely described. FIG. 2 is a conceptual diagram showing the relationship between the window size and the amount of transmission data in this embodiment. Here, it is assumed that the image to be transmitted is a monochrome image in which each pixel is 8 bits and the frame frequency is 30 Hz. In FIG. 2, 40 is an image display window of 100 × 200 pixels opened by default,
42 is the image display window 40 reduced to 1/4 5
An image display window of 0 × 100 pixels, and 44 is an image display window of 200 × 400 pixels in which the image display window 40 is magnified four times.

The image data required to display one screen image in the default image display window 40 is 20
Since it becomes k Byte and 30 screens are displayed per second, the image data required per second is 600 K Byte.
/ S. Here, the control device 22 that controls the imaging device 20 sets the transmission data amount in the initial setting to 600 kBytes.
If / s is set, it means that necessary and sufficient image data to be displayed in the image display window 40 is transmitted.

Consider a case where the image display window 40 is reduced to an image display window 42 using an operating member such as a mouse. Image display window 42 is 50x
Since there are 100 pixels, the image data required to display an image on one screen is 5 KBytes, and 30 images are displayed per second, so the image data required per second is 150 KBytes / s. The information processing device 26 notifies the control device 22 of the change in the transmission image data amount due to the change in the window size, and the control device 22 accordingly changes the transmission image data amount from 600 KBytes / s to 15 Kbytes / s.
Change to 0KByte / s. As a result, the control device 2
2 transmits to the information processing device 26 a sufficient amount of image data to be displayed in the image display window 42.

Consider a case where the image display window 40 is enlarged like the image display window 44. The image data required to display one screen image in the image display window 44 is 80 KByte, and 30 screens are displayed per second, so the image data required per second is 2, 4
It becomes 00 KByte / s. The information processing device 26 notifies the control device 22 of the change in the transmission image data amount due to the change in the window size, and the control device 22 responds accordingly.
Transmission image data amount from 600 KByte / s to 2,40
Change to 0KByte / s. As a result, the control device 2
2 transmits to the information processing device 26 a sufficient amount of image data to be displayed in the image display window 44. An image with a higher resolution is displayed in the image display window 44. That is, the resolution improves as the image display window expands.

When the image pickup device 20 has a variable magnification lens such as a zoom lens as a photographing lens, it may be used together with the zoom operation. In this case, for example, as shown in FIG. 4, the slide switch 50 for zoom operation is displayed close to the image display window 52. Figure 4 (a)
4B shows a state in which the slide switch 50 is set to the tele side, and FIG. 4B shows a state in which the slide switch 50 is set to the wide side.

FIG. 5 shows an operation flow chart of this embodiment to which a slide operation is added.

The control device 22 initializes the image transmission data amount (S30) and outputs the photographed image to the communication line 24. The information processing device 26 opens the image display window (the image display window 52 of FIG. 4) in the image display device 28 with the default window size (S40), and the communication line 2
The image received from No. 4 is displayed in the image display window (S45).

When the tele / wide position is changed by the slide switch 50 by operating the operation member 30 (S4
1), the information processing device 26 notifies the control device 22 of the zoom lens movement amount corresponding to the changed tele / wide position (S42). When the control device 22 detects a zoom lens movement request from the information processing device 22 (S31), the control device 22 drives the zoom lens of the imaging device 20 to a corresponding zooming position (S32).

When the size of the image display window 52 is changed by the operation of the operation member 30 (S43), the information processing device 26 notifies the control device 22 of the transmission image data amount corresponding to the changed window size. Do (S
44). Upon receiving the notification of the change of the transmission image data amount (S33), the control device 22 changes the setting of the image data amount to be transmitted (S34) and transmits the captured image with the transmission image data amount to the information processing device 26. (S35).

In FIGS. 4 and 5, the zoom lens operation is described as an example, but it is obvious that the shooting direction of the image pickup apparatus 20, the shooting time, the auxiliary illumination at the time of shooting, and the like can be similarly operated.

In reality, there is an upper limit to the data transmission rate depending on the type of communication line and communication protocol. Even if the information processing device 26 requests the control device 22 to exceed the maximum communication speed of the communication line 24, it is clear that the maximum communication speed of the communication line 24 cannot be exceeded. Figure 6
The operation | movement flowchart with respect to the upper limit of communication speed is shown. For the sake of explanation, it is assumed that the practical upper limit of the communicable data rate of the communication line 24 is 3 MByte / s.
6 requests the controller 22 for a data transmission rate of 5 MByte / s.

The control device 22 initializes the image transmission data amount (S50) and outputs it to the photographed image data communication line 24. The information processing device 26 opens the image display window on the image display device 28 with the default window size (S60), and displays the image received from the communication line 24 in the image display window (S66).

When the window size is changed by operating the operation member 30 (S61), the information processing device 26
It is determined whether or not the transmission image data amount corresponding to the changed window size needs to exceed the maximum communication speed (S62), and when the maximum communication speed is required, the transmission image corresponding to the maximum communication speed is determined. The data amount is notified to the control device 22 (S63), and if not, the transmission image data amount corresponding to the changed window size is notified to the control device 22 (S65).

In response to the notification of the change of the transmission image data amount from the information processing device 26 (S51), the control device 22 changes the setting of the transmission image data amount (S52), and acquires the captured image with the transmission image data amount. The information is transmitted to the information processing device 26.

When the image data exceeding the maximum communication speed is required (S62), the information processing device 26 uses the image data received from the control device 22 as the image data amount corresponding to the size of the image display window. Interpolate up to and display an image. That is, while the maximum communication speed is 3 MByte / s, the amount of image data corresponding to the image display window size is 5 MByte / s.
6 displays the received image as an image while interpolating the data of 2 MByte / s.

In FIG. 6, the information processing device 26 determines whether or not the amount of transmission image data required to be displayed in the image display window is within the maximum communication speed, but of course the control device 22 side. Alternatively, the control device 22 may notify the information processing device 26 of the actually transmitted image data amount.

[0032]

As can be easily understood from the above description, according to the present invention, it is possible to provide an image transmission system for efficiently controlling the amount of transmitted image data according to the image utilization state on the image receiving side. Further, this improves the utilization efficiency of the transmission medium and also improves the resolution of the display image.

[Brief description of drawings]

FIG. 1 is a schematic block diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a size of an image display window and a transmitted image data amount according to the present embodiment.

FIG. 3 is a first operation flowchart of this embodiment.

FIG. 4 is an example of a screen displaying a slide switch for zoom operation.

FIG. 5 is an operation flowchart of the present embodiment combined with a zoom operation.

FIG. 6 is an operation flowchart for coping with the maximum communication speed.

FIG. 7 is an explanatory diagram of an image display window.

[Explanation of symbols]

20: Imaging device 22: Control device 24: Communication line 2
6: Information processing device 28: Image display device 30: Operation member

Claims (5)

[Claims] 1. An image transmission system for transmitting an image picked up by an image pickup means via a transmission line and displaying it on a screen of an image display means in one of a plurality of sizes which can be freely selected. An image transmission system characterized in that it can be changed according to the display size on the screen of the image display means. 2. An image transmission system for transmitting an image picked up by an image pickup means via a transmission line and displaying the image on the screen of the image display means, wherein the transmitted image data amount is displayed on the screen of the image display means. An image transmission system characterized by being sized. 3. An image pickup means for picking up an image, an image pickup control means for controlling the image pickup means, a transmission medium for transmitting the image picked up by the image pickup means, and an information processing means for receiving the transmitted image. An image transmission system having a display unit for displaying an image received by the information processing unit and an operation unit for operating an image display on the display unit, the image transmission system according to the image display operated by the operation unit. An image transmission system characterized in that the information processing means notifies the imaging control means of the amount of transmission image data so that the information processing means can change the transmission data rate of the imaging control means. 4. The image processing apparatus according to claim 3, wherein the information processing apparatus notifies the image capturing control section of an operation request of the image capturing section, and the image capturing control section controls the operation of the image capturing section according to the operation request. Image transmission system. 5. When the image transmission data rate required by the information processing device is larger than the maximum value of the transmission rate according to the physical characteristics of the transmission medium and the communication protocol, the image transmission is automatically performed at the maximum transmission rate. The image transmission system according to claim 3.