JPH08265731A - Bidirectional picture communication method and system - Google Patents

Abstract

PURPOSE: To miniaturize a terminal and to facilitate editing by transferring picture information from a terminal by using the communication channel of a high speed when the pictures from the terminal are registered to the information storage means of a center unit and transferring the picture information to the terminal by using the communication channel of a low speed when the picture information is read out. CONSTITUTION: In a communication network, the center 11 is provided with a high compression encoding means and a picture information storage means. Also, the respective terminals 13-1-13-5 are provided with a low compression encoding means and a high compression decoding means. In the case of transferring from the terminal 13-1 to the direction of the center unit 11, the communication channel of VC-4 is required so as to transmit linear encoded picture information. On the other hand, from the unit 11 to the terminal 13-1, the information is compressed by using the high compression encoding of MREG2 or the like. VC-2 is required as the communication channel so as to carry the information and it can contain 21 lines in an STM-1. Thus, as the number of the terminals capable of simultaneously accessing the unit 11, the maximum of 84 terminals can simultaneously perform access.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-way image communication method and system, and more particularly, it stores image information inputted at terminals in a center device and reads it out at any time by a plurality of terminals.
The present invention relates to a bidirectional image communication method and system for displaying and outputting image information.

[0002]

2. Description of the Related Art Conventionally, a center device having a storage device for accumulating image information and a plurality of terminals are connected by a bidirectional transmission line (communication channel), image information is inputted from the terminals, and the inputted image information is inputted. In a bidirectional image communication system in which image information is stored in a center device, read out, transmitted, and displayed on a plurality of terminals, the image information is processed by a high compression encoding means due to the enormous amount of image information. A communication system for compressing and transmitting is known.

In such an interactive image communication system,
The input image information is highly compression-encoded at each terminal, the highly compressed image information sent from the center device is decoded at the terminal side, the original image information is reproduced, and displayed and output. This makes it possible to reduce the amount of information transferred on the communication path, increase the number of terminals that can be accommodated simultaneously in a communication path having a fixed capacity, and reduce the amount of information that needs to be stored in the center device. Can be reduced.

[0004]

The present inventor has found the following problems as a result of examining the above-mentioned prior art.

That is, in the conventional bidirectional image communication system, high compression encoding means for highly compression encoding the input image information to each terminal, and decoding of the highly compressed image information sent from the center device. A high compression decoding means is required. In particular, the means for high compression coding in real time is
It is complicated and expensive, so the terminal becomes larger and
There was a problem of becoming expensive.

In order to make the high compression decoding means economical, the real-time property is lost and the input image information is temporarily stored,
There is also a system for performing high compression encoding off-line. In this system, although the high compression encoding means is economical, a new means for accumulating a large amount of input image information is required in the terminal and the center device There is a problem that the time required to send the image to the computer increases.

Further, there is a system that reduces the original image information itself that needs to be encoded. In this case, the performance required for high compression encoding is reduced by not displaying the terminal in full size, but limiting the area to, for example, 1/4.
Downsizing and economy. However, there is a problem in that it is not possible to see fine dots due to the reduced display size.

An object of the present invention is to provide a two-way image communication method and system capable of reducing the size and cost of terminals without reducing the number of terminals that can be accommodated in a communication path having a fixed capacity at the same time. Especially.

Another object of the present invention is to provide a two-way image communication method and system capable of facilitating editing of image information at a terminal when registering image information in a center device.

The above and other objects and novel features of the present invention will become apparent from the description of this specification and the accompanying drawings.

[0011]

The outline of the representative one of the inventions disclosed in the present application will be briefly described as follows.

(1) The center device and a plurality of terminals are connected by a high-speed communication channel and a low-speed communication channel, image information is registered from the terminal to the information storage means of the center device, and the center device A two-way image communication method for reading image information from a storage device, wherein when the image is registered in the information storage means of the center device, the image information is sent from the terminal using the high-speed communication channel. When transferring and reading the image information from the information storage means of the center device, the image information is transferred to the terminal using the low-speed communication channel.

(2) The center device and a plurality of terminals are connected by a communication channel, the image information is registered from the terminal to the information storage means of the center device, and the image information is stored from the information storage means of the center device. A two-way image communication method for reading, wherein, when an image is registered in the information storage means of the image center apparatus from the terminal, low compression encoded image information is transferred from the terminal to the center apparatus, Of the image information stored in the information storage means of the center device and transferred to the terminal according to a request from the terminal.
After being edited by the terminal, it is transferred to the center device, and the low compression-coded image information is highly compression-coded by the center device and then stored.

(3) A center device having a storage device for accumulating image information, a plurality of terminals having image input and output means, a communication channel connecting the terminals and the center device, and the terminal to the center. What is claimed is: 1. A bidirectional image communication system comprising: means for registering image information in a storage device of a device; and means for reading image information from a storage device of the center device from the terminal, wherein the center device has at least a high compression ratio. An encoding unit is provided, and the terminal is provided with a low compression encoding unit and a high compression decoding unit, communication channels having different communication speeds are used when registering and reading image information, and when registering image information, The image information, which is low-compression coded by the low-compression coding means of the terminal, is transferred to the center device, and high-compression-coded by the high compression coding means of the center device After that, the image information is accumulated and stored in the information accumulating means, and when the image information is read out, the highly compressed image information read out from the information accumulating means is transferred to the terminal and is decoded by the high compression decoding means of the terminal. To do.

(4) A center device having a storage device for accumulating image information, a plurality of terminals having image input and output means, a communication channel connecting the terminals and the center device, and the terminal to the center. A two-way image communication system comprising: means for registering image information in a storage device of a device; and means for reading image information from a storage device of the center device from the terminal, the storage device comprising first image information. The center device includes at least a high compression encoding unit, the terminal includes a low compression encoding unit and a high compression decoding unit, and the terminal includes the accumulation unit and the second image information accumulation unit. When registering the image information in the storage device of the center device, the image information compressed and encoded by the low compression encoding means of the terminal is transferred to the center device, Is temporarily stored stores the image information in the first image information storing means, in response to a request from the terminal,
After transferring a part or all of the stored low-compression-coded image information to a terminal and editing it at the terminal,
After the data is transferred to the center device again for storage and storage, and after the editing is completed, the low compression-encoded image information in the first image information storage means is highly compression-encoded by the high compression encoding means in the center device. , Is stored in the second image information storage means.

[0016]

According to the above-mentioned means, as a service using the interactive image communication system, there is an electronic bulletin board service that handles not only text but also image information. In such services, the major occupation of the communication path is
This is the time when a plurality of terminals simultaneously access the center and retrieve the accumulated image information.

In such a case, the fact that the frequency of attempting to store new image information in the center device is smaller than the frequency of searching and reading the image information stored in the storage device of the center device is utilized. The center device side is provided with a high compression encoding means having a compression ratio 10 times or more that of the low compression encoding means provided on the terminal side, and the terminal side is provided with a low compression encoding means and a high compression decoding means. As a result, the center device and each terminal are connected to each other through communication channels having different communication speeds when registering and reading image information, so that the terminals can be accommodated without decreasing the number of terminals that can be accommodated simultaneously in a communication path having a certain capacity. It can be made smaller and more economical.

Further, by providing the center device with means for temporarily accumulating and storing the low-compression-coded image information transferred from the terminal, the editing work for registering the image information in the center device is described above. Since the processing is performed by using the means for storing and storing, it is not necessary to have a large-capacity storage device in each terminal, and it is possible to prevent deterioration of image quality due to repeated high compression encoding and decoding. This allows
It is possible to easily edit the image information in the terminal when registering the image information in the center device.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings together with embodiments.

(Embodiment 1) FIG. 1 is a block diagram showing a schematic configuration of a network of a bidirectional image communication system according to Embodiment 1 of the present invention. Reference numeral 11 is a center having a storage device for accumulating image information. Device, 14 is a connection device, 1
3-1 to 13-5 are terminals, 120 is a bidirectional transmission path group (communication channel), and 121 is a bidirectional transmission path (communication channel).

In the network of the bidirectional image communication system according to the first embodiment, as shown in FIG. 1, the bidirectional transmission paths 120 and 121 connected in a tree form a communication path, and the center device 11 and each terminal are connected. 13-1 to 13-5 are connected. That is, the long-distance bidirectional transmission line 121 is connected to the plurality of bidirectional transmission line groups 120 via the connection device 14. Here, the bidirectional transmission line 121 is the ITU recommendation G.
662 Mb / defined by 707/708/709
s STM-4 transmission line, bidirectional transmission line group 120 is 15
It is composed of a 6 Mb / s STM-1 transmission line.

The connection device 14 collects a plurality of communication channels from the bidirectional transmission line group 120 and collects the bidirectional transmission lines 121.
To multiplex. In this way, by concentrating the lines with the connection device 14, the expensive long-distance bidirectional transmission line is shared by a plurality of terminals, thereby achieving economy.

In the case of linearly encoding normal moving image information, if the sampling frequency is 4 × fsc (14.3 Mb / s, fsc is a subcarrier frequency) and the number of quantization bits is 8 bits, the amount of information is about 114. It becomes 6 Mb / s, and information can be transferred by setting a communication channel of VC-4 between the center device 11 and each terminal (for example, the terminal 13-1).

The transmission line of the STM-1 is one VC-4
Since the STM-4 transmission line can accommodate four VC-4, the transmission line 121 in the system configuration of FIG.
Due to the above limitation, the maximum number of terminals that can simultaneously access the center apparatus 11 is limited to four.

In the first embodiment, communication channels having different communication speeds are used when registering and reading image information. Therefore, low-compressed image information is transmitted from the terminals 13-1 to 13-5 toward the center device 11 through a high-speed communication channel, and high compression is performed from the center device 11 to the terminals 13-1 to 13-5. Transferred image information through a low speed communication channel.

For example, in the network configuration of the present embodiment shown in FIG. 1, the center device 11 has a storage means (not shown) for compressed image information and a high compression encoding means (not shown). It is equipped. In addition, each terminal 13-
1 to 13-5 are provided with low compression encoding means (not shown) and high compression decoding means (not shown). Here, if the straight line coding which is the simplest coding is used as the low compression coding means, as shown above,
The transfer from the terminal 13-1 to the center device 11 requires a VC-4 communication channel for sending the linearly encoded image information.

On the other hand, the information amount from the center device 11 to the terminal 13-1 is compressed to, for example, 6 Mb / s by using high compression coding such as MPEG2. To carry this information,
VC-2 is required as a communication channel, which is ST
21 can be stored in M-1. Therefore, the number of terminals that can simultaneously access the center device 11 is as follows, and a maximum of 84 terminals can simultaneously access.

(1) Image registration terminal: 4, image reading terminal: 0 (2) Image registration terminal: 3, image reading terminal: 21 (3) Image registration terminal: 2, image Terminals for reading: 42 (4) Terminals for registering images: 1, Terminals for reading images: 63 (5) Terminals for registering images: 0, Terminals for reading images: 84 The connection device 14 is each terminal 13-1 to 13- At the time of registration of image information in response to a request from No. 5, each terminal 13-1 to 13-5
The center device 11 and the center device 11 are connected via a VC-4 communication channel, and are connected via a VC-2 communication channel when reading image information.

Generally, since the frequency of registering the image information in the center device 11 is small, it is possible to secure a sufficient number of communication channels for reading.

As can be seen from the above description, the first embodiment
According to this, the fact that the frequency of attempting to store new image information in the center device 11 is smaller than the frequency of searching for and reading out the image information stored in the center device 11 is utilized. Is provided with high compression encoding means having a compression ratio 10 times or more that of the low compression encoding means provided on the terminals 13-1 to 13-5 side, and the terminals 13-1 to 13-5 are provided.
By providing the low compression encoding means and the high compression decoding means on the side, the center device 11 and each of the terminals 13-1 to 13-5 are connected by communication channels having different communication speeds at the time of registration and reading of image information. Therefore, it is possible to reduce the size and cost of the terminals without reducing the number of terminals that can be accommodated in a communication path having a certain capacity at the same time.

(Embodiment 2) FIG. 2 is a block diagram showing a schematic configuration of a network of a bidirectional image communication system according to Embodiment 2 of the present invention. Reference numeral 31 is a center device having a storage device for accumulating image information. , 33 is a terminal, 321 is a communication channel # 1 (bidirectional transmission line group), 322 is a communication channel # 2 (bidirectional transmission line), 311 is a low compression decoding circuit, 314 is a high compression encoding circuit, 315 is A temporary data storage device (storage device) 316 is an image information storage device (storage device) that stores high compression encoded image information,
331 is a low compression decoding circuit, 332 is a low compression encoding circuit, 333 is an image registration / editing device, 334 is a high compression decoding circuit, 335 is an image display device, and 336 is a control device (control means). FIG. 2 shows the connection device, the transmission line, and
The transmission line group is omitted, and a state in which a communication line is established between the center device and a specific terminal is shown.

The two-way image communication system of the second embodiment is
As shown in FIG. 2, the center device 31 and the terminal 33 have a communication channel # 1 (321) and a communication channel # 2 (32).
2) is connected via Communication channel # 1 (32
1) has a capacity 10 times or more that of the communication channel # 2 (322).

The center device 31 has, as the functions according to the present invention, a temporary data storage device (storage device) 315 for temporarily storing low-compression-coded image information and high-compression-coded image information. The image information storage device (storage device) 316, the low compression decoding circuit 311, and the high compression encoding circuit 314, and a communication circuit (not shown) for performing digital communication with the terminal 33, the terminal 33. In accordance with instructions from the temporary data storage device 31
5. A control execution circuit (not shown) including a microprocessor for controlling the image information storage device 316 is provided.

Here, the temporary data storage device 315
Is the storage means of the low compression encoded image information of the first embodiment, the image information storage device 316 is the storage means of the high compression encoded image information of the first embodiment, and the high compression encoding circuit 314 is It corresponds to the high compression encoding means of the first embodiment.

The terminal 33 has a low compression decoding circuit 331 and a low compression encoding circuit 33 as functions according to the present invention.
2, image registration editing device 333, high compression decoding circuit 33
4, image display device 335, control device (control means) 336
And a communication circuit (not shown) for performing digital communication with the center device 31.

Here, the low compression encoding circuit 332 is the same as the low compression encoding means of the first embodiment except that the high compression decoding circuit 33 is used.
Reference numeral 4 corresponds to the high compression decoding means of the first embodiment.

When registering image information in the center device 31, the image registration / editing device 333 is an external video camera, a VT.
Original image information is fetched from R (not shown), low-compression encoded by the low-compression encoding circuit 332, and then the temporary data storage device 31 is transmitted via the communication channel # 1 (321).
5 is stored (stored).

Next, the image registration / editing device 33 for editing.
3 uses the control device 336 to instruct the temporary data storage device 315 to transfer all or part of the stored images to the terminal 33. The low compression decoding circuit 331 decodes the transferred image information and transfers it to the image registration / editing device 333. After the image registration / editing device 333 has performed necessary processing, the low compression encoding circuit 332 is executed again.
And is stored in the same storage location of the temporary data storage device 315 according to the instruction of the control device 336.

If a linear coding rule or the like is used as the low compression coding rule, and the image registration / editing device 333 performs digital processing, the low compression decoding circuit 331 becomes unnecessary. When the edited image information is stored again in the temporary data storage device 315, the low compression coding circuit 3 is used.
There is no need to encode at 32.

When the editing work is completed, the image registration / editing device 333 uses the control device 336 to transfer the image information stored in the temporary data storage device 315 to the image information storage device 316 and register it. Give instructions. The low-compression-coded image information of the temporary data storage device 315 is decoded by the low-compression decoding circuit 311 and high-compression coded by the high-compression encoding circuit 314 to reduce the amount of data. It is stored in the storage device 316.

When a linear coding rule or the like is used as the low compression coding rule, the low compression decoding circuit 311 is used.
Is unnecessary.

When the image information is read from the center device 31, the image display device 335 uses the control device 336 to instruct the image information storage device 316 to transfer the desired stored image information to the terminal 33. To do. The transferred high-compression-coded image information is decoded by the high-compression decoding circuit 334 and then passed to the image display device 335 for display.

As a communication channel (indicated by a broken line in the figure) for control from the control device 336 to the center device 31, a part of the communication channel # 1 (321) and the communication channel # 2 (322) may be used. However, another means such as a telephone line may be used.

As described above, by using the common storage device that directly stores the low-compression-coded image information for editing the image information, deterioration of the image quality due to repeated high-compression encoding and decoding is prevented. Moreover, each terminal does not need a large-capacity storage device.

In this embodiment, communication channel # 1
(321) and the communication channel # 2 (322) are established at the same time, and the case where the registration and the reading of the image information can be executed at the same time has been shown, but these may not be established at the same time.

Further, the terminal 33 may be a terminal dedicated to registration of image information or a read only terminal.

As can be seen from the above description, the second embodiment
According to this, the image information is registered in the center device 31 by providing the center device 31 with the temporary data storage device 315 that temporarily stores and stores the low-compression-coded image information transferred from the terminal 33. Temporary data accumulating device 3 for accumulating and saving the editing work when
Since it is executed using 15, the large capacity storage device is not required for each terminal 33, and the deterioration of the image quality due to the repetition of high compression encoding and decoding can be prevented. This makes it easy to edit the image information on the terminal 33 when registering the image information in the center device 31.

Next, examples other than the first and second embodiments of the present invention will be described.

(1) In the first and second embodiments, the STM (Synchronous Transfer Mode) is shown as the transmission path, but an ATM (Asynchronous Transfer Mode) may be used. In this case, since the speed of the communication channel can be set freely, the degree of freedom in selecting the coding method can be increased.

(2) As the editing of the image information, it is possible to delete a part of the image in addition to the processing to the image described above. In this case, the image registration / editing device 333 has the control device 336.
Is used to issue a necessary instruction to the temporary data storage device 315.

The inventions made by the present inventors are as follows.
Although the present invention has been specifically described based on the above-mentioned embodiments, the present invention is not limited to the above-mentioned embodiments, and it goes without saying that various modifications can be made without departing from the scope of the invention.

[0052]

The effects obtained by the typical ones of the inventions disclosed in the present application will be briefly described as follows.

(1) Since the center device and each terminal can be connected to each other through communication channels having different communication speeds at the time of registration and reading of image information, the number of terminals that can be accommodated simultaneously in a communication path having a fixed capacity is reduced. Without making it possible, the terminal can be downsized and made economical.

(2) Editing when registering image information in the center device by providing a storage device for temporarily storing the low-compression-coded image information transferred from the terminal to the center device Since the work is executed using the storage / storing means, a large-capacity storage device is not required for each terminal, and it is possible to prevent deterioration of image quality due to repeated high compression encoding and decoding. This makes it easy to edit the image information on the terminal when registering the image information in the center device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a network of a bidirectional image communication system according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a schematic configuration of a network of a bidirectional image communication system according to a second embodiment of the present invention.

[Explanation of symbols]

11 ... Center device, 13-1 to 13-5 ... Terminal, 14 ... Connection device, 31 ... Center device, 33 ... Terminal, 120 ... Transmission line group, 121 ... Transmission line, 311 ... Low compression decoding on center device side Circuits, 314 ... High compression coding circuit, 315 ... Temporary data storage device, 316 ... Image information storage device, 3
21 ... Large-capacity communication channels # 1, 322 ... Small-capacity communication channels # 2, 331 ... Terminal low-compression decoding circuit,
332 ... Low compression encoding circuit, 333 ... Image registration / editing device, 334 ... High compression decoding circuit, 335 ... Image display device, 336 ... Control device.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code Agency reference number FI Technical display location H04N 7/30 H04N 7/133 Z

Claims (4)

[Claims] 1. A center device and a plurality of terminals are connected by a high-speed communication channel and a low-speed communication channel, image information is registered from the terminal to an information storage means of the center device, and storage of the center device is performed. A two-way image communication method for reading image information from a device, wherein when the image is registered in the information storage means of the center device, the image information is transferred from the terminal using the high-speed communication channel. When the image information is read out from the information storage means of the center device, the image information is transferred to the terminal using the low speed communication channel. 2. A center device and a plurality of terminals are connected by a communication channel, image information is registered in the information storage means of the center device from the terminal, and image information is read from the information storage means of the center device. In the two-way image communication method, when the image is registered from the terminal to the information storage means of the image center device, the low compression coded image information is transferred from the terminal to the center device, The center device stores the image information stored in the information storage means, and upon request from the terminal, reads part or all of the stored image information from the information storage means of the center device, transfers the information to the terminal, edits at the terminal, and then the center device. To the center device, the center device highly compresses the low-compression-encoded image information, and then stores the image information. 3. A center device having a storage device for accumulating image information, a plurality of terminals having image input and output means, a communication channel connecting the terminals to the center device, and the terminal device to the center device. A bidirectional image communication system comprising means for registering image information in the storage device of the center device and means for reading image information from the storage device of the center device from the terminal, wherein the center device has at least a high compression code. The terminal is provided with a low compression encoding means and a high compression decoding means, wherein communication channels having different communication speeds are used at the time of registration and reading of image information, and at the time of registration of image information, After the image information that has been low-compression coded by the low-compression coding means of the terminal is transferred to the center device and is highly-compressed and coded by the high-compression coding means of the center device, The image information is accumulated and stored in the information accumulating means, and when the image information is read out, the highly compressed image information read out from the information accumulating means is transferred to the terminal and is decoded by the high compression decoding means of the terminal. An image information interactive communication system comprising a control means. 4. A center device having a storage device for accumulating image information, a plurality of terminals having image input and output means, a communication channel connecting the terminals to the center device, and the terminal device to the center device. A two-way image communication system comprising means for registering image information in a storage device of the center device and means for reading image information from the storage device of the center device from the terminal, the storage device storing first image information. Means and second image information storage means, the center device includes at least high compression encoding means, the terminal includes low compression encoding means and high compression decoding means, and When registering the image information in the storage device of the center device, the image information compressed and encoded by the low compression encoding means of the terminal is transferred to the center device,
The center device temporarily stores and stores the image information in the first image information storage means, and transfers a part or all of the stored low compression coded image information to the terminal in response to a request from the terminal. Then, after editing at the terminal, it is transferred to the center device again for storage and storage, and after the editing is completed, at the center device, the low compression coded image information in the first image information storage means is stored at the high level. An image information two-way communication system comprising: a control unit that performs high compression encoding by a compression encoding unit and stores and stores in the second image information storage unit.