JPH01276853A - Packet communication video conference terminal - Google Patents

Abstract

PURPOSE:To obtain the picture of a receiving screen close to the action of the picture of a transmitting screen by packeting even the size not to reach the specified maximum packet size as one packet based on the completion of picture information. CONSTITUTION:The title terminal has a picture CODEC part 5 to encode and decode picture information and a packet transmitting control part 7 to packet the picture information encoded by the picture CODEC part 5, send it to a line and send the picture information to decompose and reproduce the packet received from the line to the picture CODEC part 5. The packet transmitting control part 7 packets the picture information not to reach the maximum packet size to specify one screen information quantity or the part not to reach the remaining maximum packet size when the information is packeted in units of the maximum packet size as one packet without awaiting the accumulation of the next picture information. Thus, the picture of the receiving screen to execute the action close to the picture of the transmitting screen is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a packet communication television conference terminal that transmits and receives image information in packet form.

[Conventional technology]

FIG. 4 is a block diagram showing a conventional packet communication video conference terminal. In the figure, 1 is a television camera that captures images to be transmitted, 2 is a monitor that displays received image information, and 3 is a packetized 4 is a packet communication teleconferencing terminal arranged between the television camera 1 and monitor 2 and the line 3, and 5 is a line through which image information is transmitted;
6 is an image codec unit to which the television camera 1 and monitor 2 are connected, and performs encoding of image information from the television camera 1 and decoding of image information to the monitor 2; 6 is connected to the image codec unit 5; A packet transmission control section that packetizes the image information encoded by the image codec section 5 and sends it to the line 3, and also sends the image information that has been decomposed and reproduced from the packets received from the line 3 to the image codec section 5. The packet communication teleconference terminal 4 is composed of the image codec section 5 and the packet transmission control section 6.

Further, 11 is a central processing unit (hereinafter referred to as CPU) that controls the entire packet transmission control unit 6, 12 is a program memory that stores the CPU II program and is connected to a bus from CPU II, and 13 is connected to the bus. 14 is a line control unit connected between the bus and the line 3 to control transmission and reception of packets; 15 is a line control unit between the bus and the image codec unit 4; This is a packetization control section that is connected to control packetization and packet disassembly, and the packet transmission control section 6 is constituted by these sections.

Next, the operation will be explained. Image information captured by the television camera 1 is sent to the packet communication television conference terminal 4,
The image is input to the image codec section 5. This image information is encoded by the image codec section 5, sent to the packet transmission control section 6, and input to the packetization control section 15 thereof. The encoded image information is divided into fixed packet sizes, for example, NP, and packetized by the packetization control unit 15. The encoded image information is once stored in the data memory 13, and is sequentially transmitted from the line control unit 14 to the line 3 for each packet. Sent out.

Here, FIG. 5 is a flowchart showing the operation procedure of bucket 1-ization by the packetization control unit 15, and FIG. 6 is a conceptual diagram of the packetization. Usually, the image codec section 5
The image information encoded in
The amount of screen information) is not constant and constantly changing. Therefore, the packetization control unit 15 first transfers the encoded image information, in which the amount of information per screen changes, received from the image codec unit 5 in step STI to the data memory 13, and stores the -time therein. do. At that time, data memory 13
In step S 'I', it is determined whether the amount of information accumulated in the fixed baguette size Np is counted.
Monitor at 2. The amount of information is a fixed packet size Np
When it reaches the fixed packet size Np, it is packetized in step ST3 with the fixed packet size Np. When the packetization is completed, the line control unit 14 sends the packets to the wire 3 in units of packets, and packetization of the next image information is started.

Therefore, when the image information shown at the beginning of the sending direction in FIG. 6, the amount of information for one screen is less than the fixed packet size Np, is stored in the data memory 13 as part of the next image information. is packetized as one packet after the amount of information is accumulated from the fixed bucket yl to the size Np. In addition, if the amount of information per screen is larger than the fixed packet size Np, such as the image information that follows, it is divided into fixed buckets 1 - size Np and packetized, and as shown in the figure, the final part has a fixed packet size. If there is a portion less than NP, then it is packetized after the amount of information in the data memory 13 is accumulated to the fixed packet size Np by a part of the next image information, as in the case described above.

Incidentally, as an approximation technique, there is Japanese Patent Application Laid-Open No. 61-48282.

[Problem to be solved by the invention]

Since the conventional packet communication video conference terminal is configured as described above, the packetization of the packetization transmission control unit 6 (jA information must be done in units of a fixed packet size Np, and the amount of generated image information is In the case of a small screen with little movement, it takes time for information to be stored in the fixed packet size Np.Therefore, the image information output from the image codec unit 5 to the monitor 2 is faster than the actual movement. There was a problem in that the movement of the image on the receiving screen differed from the movement of the image on the transmitting screen due to repeated operations and pauses for a certain period of time.

This invention was made to solve the above-mentioned problems, and its purpose is to provide a packet I/communication video conference terminal that can output to the receiving side a screen that closely resembles the actual screen movement on the sending side. do.

[Means to solve the problem]

The packet communication teleconference terminal according to the present invention packetizes the encoded image @ information from the image codec unit with the information amount of one screen when the amount of information of one screen does not satisfy the specified maximum packet size, Furthermore, when the amount of information on one screen exceeds a specified maximum packet size, the device is provided with a packet transmission control section that divides the information into a plurality of packets and packetizes each one.

[Effect]

The packet transmission control unit according to the present invention provides image information whose amount of information per screen is less than the specified maximum packet size;
Or, when packetizing in units of the maximum packet size, the remaining portion that is less than the maximum packet size,
To realize a packet communication teleconference terminal which can obtain an image of a receiving screen whose motion is similar to that of an image of a transmitting screen by packetizing it as one packet without waiting for the accumulation of the next image information.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is a television camera, 2 is a monitor, 3 is a line, 4 is a bucket 1 to a communication video conference terminal, 5 is an image codec unit, 11 is a CPU, 12 is a program memory, 13
14 is a data memory, and 14 is a line control unit, which are the same or equivalent parts to those in the conventional system denoted by the same reference numerals in FIG. 4, and detailed explanations thereof will be omitted. Further, 16 is a packetization control unit corresponding to the conventional packetization control unit 15,
When the amount of information for one screen of the encoded image information from the image codec unit 5 is less than a specified maximum packet size, for example, Np, packetize the amount of information for one screen,
This method is different from the conventional method in that when the amount of image information t1 for one screen is larger than the maximum packet size Np, it is divided into a plurality of parts and each is made into a packet. Reference numeral 7 denotes a packet transmission control section comprising this packetization control section 16, the CPU 11, the program memory 12, the data memory 13, and the line control section 14.

Next, the operation will be explained. As in the conventional case, the image information captured by the television camera 1 is sent to the image codec section 5 of the packet communication television conference terminal 4 and encoded, and then sent to the packetization control section 16 of the bucket 1 to transmission control section 7. The data is packetized and stored in the data memory 13. The image information stored in the data memory 13 is sequentially sent to the four wires 3 from the line control section 14 for each baguette.

Here, FIG. 2 is a flowchart showing the operation procedure of packetization by the packetization control unit 16, and FIG. 3 is a conceptual diagram of the packetization. As in the conventional case, in step ST1, the packetization control section 16 first transfers the changing screen information of one screen information amount from the image codec section 5 to the data memory 13 and stores it there. then,
In step ST4 and step ST2, it is monitored whether the image information for one screen has been completed and whether the amount of information accumulated in the data memory 13 has reached the specified maximum packet size Np. ing. When it is detected in step ST2 that the amount of information accumulated in the data memory 13 has reached the maximum packet size Np, step S'r
' 3, it is packetized with the maximum bucket 1 to size Np. Further, when the end of one screen's worth of image information is detected in step ST4, if the maximum pagent size N has not been reached, it is directly packetized. When the packetization is completed, it is sent to the line control unit 14 in packet units.
The image information is then sent to line 3, and packetization of the next image information is started.

Therefore, if the amount of information on one screen is less than the maximum packet size NP, such as the image information shown at the beginning of the sending direction in FIG. 3, the next image information will be stored in the data memory 13 up to the maximum packet size Np. without waiting to be
It is packetized into one packet with the same size. In addition, if the amount of information per screen is larger than the maximum packet size NP, such as the image information that follows, it is divided into packets of baguette size Np, and as shown in the figure, the maximum packet size is If a portion smaller than the size Np appears, the process does not wait for the next image information to be stored in the data memory 13 up to the maximum packet size Np.
It is packetized with that size.

〔Effect of the invention〕

As described above, according to the present invention, even if the size is less than the specified maximum packet size, it is configured to be packetized as one packet based on the end of the image information. This has the effect of eliminating the waiting time after the transmission, and providing an image on the receiving screen that is close to the movement of the image on the sending screen.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a packet communication video conference terminal according to an embodiment of the present invention, and FIG. 2 is a block diagram showing its operation 14.
3 is a conceptual diagram of packetization, FIG. 4 is a block diagram of a conventional packet communication video conference terminal, FIG. 5 is a flowchart showing its operation procedure, and FIG. 6 is a diagram of its packetization. This is a conceptual diagram. 3 is a line, 4 is a packet communication video conference terminal, 5 is an image codec section, and 7 is a packet transmission control section. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Figure 5 NP: Hard 1〒2]

Claims (1)

[Claims] an image codec unit that encodes and decodes image information; and an image codec unit that packetizes the image information encoded by the image codec unit and sends it to the line, and also transmits the image information obtained by disassembling and reproducing the packets received from the line to the In a packet communication video conference terminal having a packet transmission control unit that sends a packet to an image codec unit, the packet transmission control unit determines that the amount of information for one screen of the image information encoded by the image codec unit is a specified maximum packet size. If the amount of information on one screen exceeds the maximum packet size, the amount of information on one screen is divided into multiple packets and each is packetized. A packet communication video conference terminal characterized by: