JPS62194775A - Picture transmission system and its terminal equipment and communication network managing equipment - Google Patents

Abstract

PURPOSE:To send mutually a picture between terminal equipments having different display devices by applying a picture signal processing indispensable to mutual communication in matching with the characteristic of opposed terminal equipments and sending a picture signal to be sent in response to different items of mutual terminal equipment characteristic. CONSTITUTION:A terminal equipment 50 consists of a display device 53 and a picture signal processing unit 51 consisting of a magnifying device, a reducing device, a segmentation device, a converter of bit number per picture element, a scanning converter, a coder and a controller controlling each device. The picture processing unit is connected by a communication controller 52 to a communication line, the terminal equipment characteristic indispensable to the mutual communication, the picture signal processing unit 51 applies a picture signal processing indispensable to the mutual communication to the sent picture signal in the transmission and the received picture signal in the reception depending on the different items of the terminal characteristic.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a transmission method and apparatus that enable image transmission to different terminals using display devices.

(Prior art) Conventionally, communication means using images include telewriting,
Electronic blackboards, facsimiles, still image and video teleconferencing, etc. are well known. Using regular audio lines or high-speed dedicated lines, telewriting and electronic blackboards can send and receive drawing information, facsimiles can send binary images, still image teleconferencing systems can send still images, and video teleconferencing can send and receive video. These devices use highly efficient encoding technology to compress large amounts of data and transfer it at high speed.

(Problem to be solved by the invention) However, in conventional image transmission systems, image data has a huge amount of information, so the problem is how to encode it efficiently (encode and send it at high speed). The focus was on bandwidth compression technology.With terminals using conventional transmission methods, images can only be transmitted to the same model due to differences in resolution, scanning method, number of bits per pixel, presence or absence of color control information, and encoding method. It had the disadvantage of being exposed.

On the other hand, with the development of communication means, many terminals are now connected to high-speed networks and can communicate with each other. However, it was mainly used for services using text such as e-mail, and services using images were only used between dedicated terminals. This is because there was no method for transmitting images between different terminals of display devices on a network.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a system and an apparatus for making it possible to mutually transmit images between terminals with different display devices.

(Means for Solving the Problems) The image transmission method of the present invention that solves the above problems includes resolution, scanning method, number of bits per pixel, and encoding method as characteristics of display devices of mutual terminals. Identify the terminal characteristics essential for mutual communication, match the image signal to be transmitted to the characteristics of the other terminal according to the identification information, and perform the image signal processing essential for mutual communication according to the different items of the terminal characteristics. It is characterized by transmitting information.

The terminal device of the present invention includes an image signal processing device and a display, which are configured of an enlargement device, a reduction device, a clipping device, a conversion device for the number of bits per pixel, a scan conversion device, an encoding device, and a control device for controlling each device. The device is connected to a communication line by a communication control device, identifies terminal characteristics essential for mutual communication, and uses the image signal processing device to process the image signal to be transmitted during transmission and the received image signal during reception. The image processing device is characterized in that it performs image signal processing essential for mutual communication according to different items of terminal characteristics.

The communication network management device of the present invention also provides an image signal that includes an enlarging device, a reducing device, a cutting device, a converting device for the number of bits per pixel, a scan converting device, an encoding device, and a control device for controlling each device. When transmitting and receiving image signals between terminals that are equipped with a processing device and an image storage device and that are connected to a terminal by a communication control device and have different display device characteristics, the terminal characteristics that are essential for mutual communication are stored in the image storage device and are connected to a terminal by a communication control device. The present invention is characterized in that the image signal processing device performs image signal processing essential for mutual communication in accordance with different items of the terminal characteristics and transmits the data.

(Operation) A method of transmitting images of the present invention between terminals with different display device configurations will be described.

As shown in FIG. 1(a), image transmission involves the following steps: 10-Establishment of connection 11-Discussion of communication conditions 12-Communication 13-Release of connection. The reason why data cannot be easily transmitted between different terminals is that the configuration of the terminal's display device and the encoding method differ depending on the terminal. Therefore, the problem can be solved by identifying these terminal characteristics and converting the image data before sending it when negotiating communication conditions.

Figure 1 (b) shows the specific items to be identified: 20 Horizontal resolution of one screen 21 Vertical resolution of one screen 22 - Amount of information per pixel 23 - Scanning method 24 - Encoding method 25 - Presence of color control information 26 - The presence or absence of an image signal processing device, etc., which characterizes the image memory of the terminal.

FIG. 1(c) shows the data format for image transmission in the present invention, which is in the form of 30-image attribute information 31-image data, and has attribute information indicating image characteristics as a header of the image data. .

FIG. 1(d) shows specific items of attribute information: 40 - Control command indicating image data 41 - Horizontal resolution of image data 42 - Vertical resolution of image data 43 - Amount of information per pixel 44 - Scanning method 45 - Encoding method 46 - Size of image data 47 - Presence or absence of color control information 48 - Color control information By performing image processing and display based on this, images can be transmitted and displayed even between terminals with different display devices. can do.

Note that color control information can be omitted if the terminal has a black and white screen.

Actual image processing is performed by the terminal on the communication network side. Furthermore, this transmission method is a high-level protocol, and the lower-level protocols follow the communication network to be used.

(Embodiment) FIG. 2(a) is a basic configuration diagram of an embodiment in which the image transmission system of the present invention is implemented on the terminal side. 5o is a terminal device,
It includes an image signal processing device 51 that processes image data and a communication control device 52 that controls communication. 53 is a display device for displaying images, 54 is an image input device for inputting images, and 55 is an external storage device. The terminal device, the display device, and the image 1! The input device and the external storage device constitute a terminal, and are interconnected using 56 communication lines.

FIG. 2(b) is a configuration diagram of the image signal processing device,
An enlargement device 1 for enlarging an image, a reduction device 2 for reducing an image,
A cutting device 3 that performs cutting, a bit conversion device 4 that performs bit number conversion, a scan conversion device 5 that performs scan conversion, and an encoding device 6 that performs encoding are connected in parallel, and the overall control is performed by an image processing control device. Do it with

This device is connected between the display device 53 and the communication control device 56.

A method for transmitting images in a terminal device having such a configuration will be explained.

As shown in FIG. 1(a), image transmission involves the steps of 10-Establishment of connection 11-Discussion of communication conditions 12-Communication 13-Release of connection. The terminal device 50 establishes a connection with the other terminal using the communication control device 52 according to the protocol of the communication line to be used. Next, terminal characteristics are identified when negotiating communication conditions.

Figure 1 (b) shows the specific items to be identified: 20 Horizontal resolution of one screen 21 Vertical resolution of one screen 22 - Amount of information per pixel 23 - Scanning method 24 - Encoding method 25 - Presence of color control information 26-This is the presence or absence of an image signal processing device, and is an amount that characterizes the image memory of the terminal.

Next, for consultation, the image signal processing device 51 is used to process image data, and the communication control device is used to transmit the image data to the other party's terminal.

FIG. 1C shows a data format for image transmission according to the present invention, which is in the form of 30-image attribute information 31-image data, and has attribute information indicating image characteristics as a header of the image data.

Figure 1(d) shows specific items of attribute information: 40 - Control command indicating image data 41 - Horizontal resolution of image data 42 - Vertical resolution of image data 43 - Information per pixel 44 - Scanning method 45 - Encoding method 46 - Size of image data 47 - Presence or absence of color control information 48 - Color control information.

Since image signal processing is performed by a terminal equipped with the image signal processing device 51, images can be displayed on different models as long as a transmission procedure is introduced. Furthermore, images can be used even on terminals that do not have an image signal processing device or an image input device.

Note that color control information can be omitted as long as it is between terminals with black and white screens.

Furthermore, although this embodiment deals with still images, it can also deal with moving images in exactly the same way.

FIG. 4 is a block diagram of a terminal device that more specifically represents an embodiment of the present invention.

A microprocessor 70 controls the terminal device 50 in FIG. 2, and interfaces with the following peripheral devices via a bus 71. The communication control interface 72 performs a communication line interface. The image signal processing device 73 performs image processing in accordance with the characteristics of the other party's terminal.

Image memory 74 records image data, the contents of which are displayed on a display device. An image input interface 75 controls the image input device and writes image signals into the image memory. A ROM 76 stores a program for controlling the microprocessor. A memory (RAM) 77 is a working memory of the microprocessor. Reference numeral 78 is an interface for various input/output devices that constitute the terminal, including a keyboard.

FIG. 5 shows a specific example of the configuration of the image signal processing device 73. The image signal processing device is connected to a bus 71 of a microprocessor via a bus controller 80, and on an internal local bus 81 there is an image signal processing processor 82, a ROM 83 that carries its firmware, a working memory 84 for the signal processing, and an image processing device. It has an input/output control processor 85 that transfers image data between the memory 77 and the working memory. The image signal processing processor processes image data in working memory at high speed according to firmware. In this embodiment, a single image processing processor 82 includes an enlarging device 1, a reducing device 2, a cutting device 3, a converting device 4 for converting the number of bits per pixel, and a scanning converting device 5.
, the encoding device 6 is realized.

The method for transmitting images in the terminal device having the above configuration will be explained in order from the transmitting side.

In the terminal device, the microprocessor 70 uses the terminal control interface 72 to establish a connection with the other terminal according to the protocol of the communication line to be used. Next, terminal characteristics are identified when negotiating communication conditions with the other terminal.

Figure 1 (b) shows the specific items to be identified: 20 Horizontal resolution of one screen 21 Vertical resolution of one screen 22 - Amount of information per pixel 23 - Scanning method 24 - Encoding method 25 - Presence of color control information 26 - The presence or absence of an image signal processing device, etc., which is the amount that characterizes the image memory of the terminal, and is exchanged with each other prior to communication to arrange the image processing procedure.

Image processing is performed according to the terminal characteristics of each terminal using the image signal processing device 73 as follows: a - Scanning conversion - Enlargement/reduction C - Clipping d - Bit number conversion per pixel e - Encoding f - Color control information Create.

Image data is first transferred from image memory 74 to working memory 84 using input/output control processor 85 under control of microprocessor 70 . The microprocessor 70 performs image processing according to the flowchart of image signal processing shown in FIG. First, if the image to be sent is in interlaced scanning format, image processing may be complicated, so scan conversion is performed to convert the image to sequential scanning (non-interlaced).
Convert to method.

Next, if the resolutions of the two terminals are different, enlargement or reduction is performed, and if the aspect ratios are different, the image is cut out according to the aspect ratio. Furthermore, if the number of bits per pixel is different, the number of bits is converted and the number of bits is expanded or compressed. Furthermore, some terminals require color control information such as a color map for color images, so create one if necessary. Finally, scan conversion is performed according to the scanning method of the receiving terminal, and if a common encoding method can be used, encoding is performed to compress the image and the image processing is completed.

These image processes are controlled to reduce the amount of image processing and transmission, such as cutting out images to fit a smaller screen size when the aspect ratios are different.

The color control information is created by a microprocessor, but everything else is processed at high speed by an image signal processor. Finally, the input/output control/processor 85 transfers the processed image data from the working memory 84 to the memory 77.
to complete image signal processing.

FIG. 1(C) shows the data format for image transmission in the present invention, which has the form of 30-image attribute information 31-image data, and has attribute information indicating image characteristics as a header of the image data. The image data after the image processing is transmitted in this format via the communication line using the communication control interface 78.

FIG. 1(d) shows specific items of attribute information: 40 - Control command indicating image data 41 - Horizontal resolution of image data 42 - Vertical resolution of image data 43 - Amount of information per pixel 44 - Scanning method 45 - Encoding method 46 - Size of image data 47 - Presence or absence of color control information 48 - Color control information.

Finally, the connection to the other party's terminal is released, and the image transmission is completed. Image processing is performed by a terminal equipped with an image signal processing device. If possible, do this on the sending side of both terminals. This will be determined at the time of communication terms negotiation.

Next, the receiving side terminal will be explained.

The operations on the receiving side are almost the same as those on the transmitting side; a connection is established with the other party's terminal, communication conditions are negotiated according to FIG. 1(b), and image data is received. Here, if the transmitting terminal does not have an image signal processing device, the receiving terminal performs image processing according to the processing procedure shown in FIG. 6, and the transmission ends. Then, the connection with the other party's terminal is released, and the image transmission is completed.

Also, FIG. 3(a).

(b) and (c) are basic configuration diagrams of an embodiment in which the image transmission method of the present invention is implemented on the communication network side. This is a method in which the image processing device 73 is provided on the communication network side to perform centralized processing.

FIG. 3(a) shows the case of a switched network, and the communication network management device corresponds to the switch 61. The exchange temporarily stores the data from the terminal, performs necessary image processing using the image processing device 73, and then transmits the data. Figure 3(b) is a bus type,
Figure (e) corresponds to a loop type network, and the communication network management device is a server 62 on the network. In this case as well, this is achieved by sending the address and image data of the other party to the server without directly communicating with the other party's terminal, processing the image on the server using the image processing device 73, and then sending it to the other party's terminal.

FIG. 3(d) is a configuration diagram of the image signal processing device and the image storage device, and includes an enlargement device 1 for enlarging the image, a reduction device 2 for reducing the image, a cutting device 3 for cutting out the image, and a bit number conversion device. It has a bit conversion device 4 for performing scan conversion, a scan conversion device 5 for performing scan conversion, and an encoding device 6 for encoding, which are connected in parallel to an image storage device 8 for storing images. The storage device is connected to each terminal via a communication control device 9. Further, the entire control is performed by the image processing control device 7. This device is connected to the exchange 61 and server 62, and processes multiple images simultaneously and in parallel.

A method for transmitting images in a communication network management device having such a configuration will be explained. In the case of communication on the network side, after establishing a connection with the exchange 61 and server 62, the transmitting terminal 60 immediately sends the image data to 90-90 as shown in FIG. 7 without negotiating the communication conditions for image communication. It is sent to the exchange 61 or server 62 in the form of destination address 91 - image attribute information 92 - image data. The image attribute information and image data are the same as those shown in FIGS. 1(c) and 1(d), and are in the format in which the address of the other party's terminal is added after the image data.

After the exchange or server stores the sent data in the image storage device 8, it releases the connection with the sending terminal, sets it as an address, and establishes a connection with the receiving terminal.
It performs the same operation as the terminal device described above. In other words, the exchange or server negotiates with the terminal on the receiving side the best communication conditions for the data on the sending side in the form shown in FIG. This transmission method is realized by processing the image and sending it to the other party in the formats shown in FIGS. 1(c) and 1(d).

In this configuration, since the image signal processing device is provided on the communication network side, images can be used even in terminals that do not have an image signal processing device or an image input device, as long as a transmission procedure is introduced.

(Effects of the Invention) By using the image transmission method of the present invention, images can be transmitted not only between conventional terminals of the same model, but also between terminals with different display device configurations. This makes it possible to use various services using images across a wide range of devices.

[Brief explanation of drawings]

Figures 1 (a), (b), (c), and (d) are diagrams explaining the transmission procedure of the image transmission method of the present invention, and Figures 2 (a), (
b) is a basic configuration diagram of a terminal device when the present invention is implemented in a terminal; FIG. 3(a); (b), (c), and (d) are basic configuration diagrams of a communication network management device when the present invention is implemented on the communication network side. FIG. 4 is a concrete block diagram of the terminal device. FIG. 5 shows an example of the configuration of the image signal processing device in the embodiment shown in FIG. FIG. 6 is a flow chart of processing by the image signal processing device. FIG. 7 shows the transmission mechanism between the sending terminal and the communication network management device when the image transmission method of the present invention is realized on the network side. - Vertical resolution 43 - Information amount per pixel 44 - Scanning method 45 - Coding method 46 - Image data size 41 - Color control information retention 48 - Color control information Fig. 2

Claims (3)

[Claims] (1) In an image transmission method that transmits and receives image signals between terminals, the characteristics of the display devices of each terminal are essential for mutual communication, including resolution, scanning method, number of bits per pixel, and encoding method. The terminal characteristics are identified, and according to the identification information, the image signal to be transmitted is matched to the characteristics of the other terminal, and the image signal processing essential for mutual communication is performed in accordance with the different items of the terminal characteristics of each other. Featured image transmission method. (2) An image signal processing device including an enlargement device, a reduction device, a cutout device, a conversion device for the number of bits per pixel, a scan conversion device, and an encoding device connected in parallel, and a control device that controls each device. The terminal characteristics essential for mutual communication are identified between terminal devices equipped with a display device and connected to a communication line by a communication control device, and the image signal processing device identifies the image signal to be transmitted during transmission and the image signal to be transmitted during reception. . A terminal device characterized by the image processing device that performs image signal processing essential for mutual communication on received image signals according to different items of terminal characteristics. (3) An image signal processing device including an enlargement device, a reduction device, a cutout device, a conversion device for the number of bits per pixel, a scan conversion device, and an encoding device connected in parallel and a control device for controlling each device. In a communication network management device equipped with an image storage device and connected to a terminal by a communication control device, when transmitting and receiving image signals between terminals with different display device characteristics, the image signal is stored in the image storage device and is essential for mutual communication. A communication network management device characterized in that the image signal processing device performs image signal processing essential for mutual communication in accordance with different items of the terminal characteristics and transmits the data.