JPH06189105A - Image transmission system, image transmission equipment, and image reception equipment - Google Patents

Abstract

PURPOSE:To transmit image information with resolution and picture quality required by an image reception side by transmitting utilization purpose information from the image reception side to an image transmission side, and transmitting by compressing an image to be transmitted by the image transmission side according to the utilization purpose. CONSTITUTION:Image transmission is performed by connecting a line by a CCU 26, and receiving the number of images of multi-picture from the image reception side. A compressibility can be decided by fitting the received number of images in a table 12a. The designated number of images is fetched from an image input/output device 20 in image memory 22, and also, they are synthesized to a multi-picture. The multi- picture generated by synthesis is compressed at a compression/expansion circuit 24. Compression information is transferred to the CCU 26 via the image buffer 14a of a RAM 14, and the compression information is transmitted. Image reception is performed by transmitting the inputted number of images to an image input side, and receiving compression image information compressed with the compressibility in accordance with the number of images. Such information is transferred to the compression/expansion circuit 24, and is stored in the image memory 22. The information is displayed on a monitor screen as the multi-picture.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission system for compressing and transmitting image information, and an image transmitting apparatus and an image receiving apparatus thereof.

[0002]

2. Description of the Related Art In a conventional image transmission system for compressing and transmitting image information, the image transmitting side determines the compression rate of the image information regardless of the purpose of use at the image receiving side.

[0003]

However, image output devices such as printers and monitors are provided with various resolutions or image qualities. Therefore, not only can the image transmission system assume a situation in which the resolution or image quality of the image output device differs depending on the device configuration of the other party to which the image is to be transmitted, but a plurality of monitors having different resolutions are connected to the receiving side terminal, It is also possible to select a monitor to which an image is to be output with the intention of the image receiving side.

In the conventional example, since the image receiving side unilaterally determines the compression rate, a compression rate which does not match the resolution or the image quality required by the image receiving side may be selected, and the following inconveniences occur. Was occurring.

That is, in the case of a compression rate of image quality exceeding the image quality requested by the image receiving side, an unnecessary portion is included in the transmission data, and, for example, there is a problem that an unnecessarily long transmission time is required.

On the other hand, when the compression rate is such that the image quality does not reach the image quality required by the image receiving side, the image receiving side must either be patient with the image quality of the received image, or by a telephone call or the like, a recompression at a lower compression rate is required. The image transmission side is requested to transmit.

An object of the present invention is to provide an image transmission system, an image transmission device and an image reception device which do not cause such inconvenience.

[0008]

An image transmission system according to the present invention is an image transmission system for compressing and transmitting image information, wherein an image receiving side transmits usage purpose information to an image transmitting side prior to image transmission. However, the image transmitting side is characterized in that the image to be transmitted is compressed and transmitted according to the utilization purpose information.

The image transmitting apparatus according to the present invention comprises receiving means for receiving the purpose-of-use information from the image receiving side, and compression means for compressing and transmitting the image to be transmitted according to the purpose-of-use information. And

An image receiving apparatus according to the present invention is an image receiving apparatus of an image transmitting system for compressing and transmitting image information, and transmitting transmitting use purpose information of an image to be received before transmitting the image information. Means are provided.

[0011]

By the above means, the image receiving side can receive the image information of the required resolution or image quality. Therefore, the disadvantages of unnecessarily lengthening the transmission time, enduring poor image quality, and requesting retransmission at another compression rate are eliminated.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 shows a schematic block diagram of a communication terminal device which is an embodiment of the present invention.

Reference numeral 10 is a CPU for controlling the whole. 12
R stores fixed data and programs of the CPU 10.
OM, 14 is a RAM for temporarily storing various data and programs, 16 is an operating device equipped with key switches for giving various instructions to the CPU 10, such as dial keys, transmission keys, reception keys and multi-image display keys, 18 Is a display device that displays various status information by a liquid crystal display panel, a light emitting diode, or the like.

The ROM 12 stores a correspondence table TBL12a between the number of screens of multi-image and the compression rate. A multi-image is generally a plurality (for example,
4, 9, 16 or 25) are combined so as to be displayed at the same time, but in this embodiment, one image is displayed on one screen.
Images that display images are also included in multi-images as a special example of multi-images. An image buffer 14a for temporarily storing the compressed image information to be transmitted and the compressed image information received is set in the RAM 14.

Reference numeral 20 denotes an image input / output device including image input means such as a video camera and an image scanner, and image output means such as a video monitor and a printer, and 22 temporarily stores an image to be transmitted and a received image. Image memory, 2
Reference numeral 4 is a compression / decompression circuit that compresses and encodes an image to be transmitted and decompresses the received compressed image information. Reference numeral 26 is a communication control circuit (CC) that controls communication via a communication line such as ISDN.
U).

The above elements 10 to 26 include a control bus 28,
They are connected to each other via an address bus 30 and a data bus 32.

FIG. 3 shows an operation flowchart when transmitting an image. First, the line is connected by the CCU 26 (S
1) Receive the number of multi-images from the image receiving side (S
2). The number of received images is applied to the table 12a to determine the compression rate (S3). The specified number of images are fetched from the image input / output device 20 into the image memory 22 and combined into a multi-image. The multi-image formed by combining is compressed by the compression / expansion circuit 24 (S4).

The compressed information is transferred to the CCU 26 via the image buffer 14a of the RAM 14, and the CCU 26
Transmits this compressed information to the communication partner (S5). After transmitting the necessary information, the CCU 26 disconnects the line (S
6).

FIG. 4 is a flowchart showing the operation of receiving an image. The line is connected by the CCU 26 (S11),
Input the number of multi-images from the operation device 16 (S1
2). The number of input images is transmitted to the image transmission side (S1
3) The compressed image information compressed at the compression rate according to the number of images is received (S14). The received compressed image information is transferred to the compression / expansion circuit 24 via the image buffer 14a, expanded and stored in the image memory 22 (S1).
5).

The received image stored in the image memory 22 is read out and supplied to the image input / output device 20, and is displayed as a multi-image on the monitor screen of the image input / output device 20 (S1).
6). When the reception of the necessary compressed image information or the end of the communication is completed, the CCU 26 disconnects the line (S17).

In FIGS. 3 and 4, the number of images forming a multi-image is used as the means for designating the compression rate, but the compression rate itself may be designated. FIG. 5 shows an operation flowchart for the image transmission. First, the CCU 26 connects the line (S21), and receives the compression rate information from the image receiving side (S22). The image information is fetched from the image input / output device 20 into the image memory 22, and the image data in the image memory 22 is compressed by the compression / expansion circuit 24 at the compression rate of the received compression rate information (S23).

The compressed image information is transferred to the CCU 26 via the image buffer 14a of the RAM 14, and the CC
U26 transmits this compressed information to the communication partner (S2).
4). After transmitting the necessary information, the CCU 26 disconnects the line (S25).

FIG. 6 shows an operation flowchart when an image is received. The line is connected by the CCU 26 (S31),
Input the number of multi-images from the operation device 16 (S3
2). With reference to the table 12a, the compression rate for the input number of images is determined (S33) and transmitted to the image transmitting side (S34). The compressed image information compressed at the transmitted compression rate is received (S35). The received compressed image information is transferred to the compression / expansion circuit 24 via the image buffer 14a, expanded and stored in the image memory 22 (S3).
6).

The received image stored in the image memory 22 is read and supplied to the image input / output device 20, and is displayed as a multi-image on the monitor screen of the image input / output device 20 (S3).
7). When the reception of the necessary compressed image information is completed or the communication is completed, the CCU 26 disconnects the line (S38).

Although the transmission of a multi-image consisting of a predetermined number of images has been described as an example, it goes without saying that the same applies to normal image transmission. Further, although the embodiment in which the image receiving side transmits the compression rate to the image transmitting side has been described, other information regarding compression such as quantization step size information, horizontal / vertical resolution, and band may be used.

[0027]

As can be easily understood from the above description, according to the present invention, image information can be transmitted at the resolution or image quality required on the image receiving side. Therefore, inconveniences such as an unnecessarily long transmission time, enduring poor image quality, and requesting retransmission at another compression rate are eliminated.

[Brief description of drawings]

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

FIG. 2 is a correspondence table of the number of images in a multi-image and the compression rate.

FIG. 3 is an operation flowchart on the image transmission side.

FIG. 4 is an operation flowchart of the image receiving side corresponding to FIG.

FIG. 5 is another operation flowchart of the image transmitting side.

6 is an operation flowchart on the image receiving side corresponding to FIG.

[Explanation of Codes] 10: CPU 12: ROM 12a: Table 1
4: RAM 14a: Image buffer 16: Operating device 18: Display device 20: Image input / output device 22:
Image memory 24: Compression / decompression circuit 26: Communication control circuit (CCU) 28: Control bus 30: Address bus
32: Data bus

Claims (10)

[Claims] 1. An image transmission system for compressing and transmitting image information, wherein an image receiving side transmits usage purpose information to an image transmitting side prior to image transmission, and the image transmitting side follows the usage purpose information. An image transmission system characterized in that an image to be transmitted is compressed and transmitted. 2. The image transmission system according to claim 1, wherein the usage purpose information is information indicating whether or not the image is a multi-image. 3. The image transmission system according to claim 1, wherein the image transmission side has a correspondence table of the number of images forming a multi-image and the compression ratio, and the utilization purpose information is information regarding the number of images of the multi-image. 4. The image receiving side is provided with a correspondence table of the number of images constituting a multi-image and the compression rate, and the image receiving side applies the designated number of images of the multi-image to the corresponding table to determine the compression rate. The image transmission system according to claim 1, wherein the information regarding the determined compression ratio is transmitted to the image transmission side. 5. An image transmitting apparatus comprising: a receiving unit that receives usage purpose information from an image receiving side; and a compression unit that compresses an image to be sent according to the usage purpose information and sends the image. 6. The image transmitting apparatus according to claim 5, wherein the usage purpose information is information indicating whether or not the image is a multi-image. 7. The image transmitting apparatus according to claim 5, further comprising a correspondence table of the number of images forming a multi-image and a compression ratio, and the use purpose information is information regarding the number of images of the multi-image. 8. An image receiving apparatus of an image transmission system for compressing and transmitting image information, comprising transmission means for transmitting utilization purpose information of an image to be received prior to transmission of the image information. Image receiving device. 9. The image receiving apparatus according to claim 8, wherein the compression information is information indicating whether or not the image is a multi-image. 10. A correspondence table of the number of images forming a multi-image and the compression ratio is provided, and the transmitting means uses the information of the compression ratio corresponding to the designated number of images of the multi-image as the usage purpose information. The image receiving device according to claim 8, which transmits.