JPH05300503A - Image communication terminal equipment - Google Patents

Abstract

PURPOSE:To provide an image communication terminal equipment which can flexibly deal with various applications to the opposite party terminal just by adding the simple hardware and a control procedure. CONSTITUTION:A data area division control part 17 is provided in addition to a means which performs the multiplex transmission of the images, voices and data based on the CCITT recommendation H.221. The part 17 designates a subchannel in a frame with use of a BAS(bit rate allocation signal) code which is not defined by the H.221. Furthermore a BAS control part 13 is added together with a multiplexing/demultiplexing part 10 which transmits and receives the BAS code that shows the designated subchannel, and a control code transmission/reception part 19 which assigns the control signal on the designated subchannel for control of how to divide the frame, the selection of the transmitted/received data, the transmitting velocity of the data, and a camera, etc., of the opposite party terminal and then transfers the control signal to the opposite party terminal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image communication terminal device having a multiplex transmission function for video, audio and data.

[0002]

2. Description of the Related Art In recent years, the International Telegraph and Telephone Advisory Committee (hereinafter referred to as
CCITT) formally recommends video coding method, multiplexing method, and communication procedure for audiovisual services, and CCIT from each company accordingly.
An image communication terminal device such as a TV conference system and a moving image TV phone that comply with the T recommendation has been developed.

A conventional image communication terminal device which performs processing in accordance with the CCITT recommendation will be described below with reference to the drawings.

FIG. 3 shows a functional block diagram of a conventional image communication terminal device. In FIG. 3, 1 is a camera for taking a self-portrait, 2 is a monitor for displaying the image or self-portrait from the other party, 3 is a microphone, Reference numeral 4 is a speaker, 5 is a tablet for performing telewriting, 6 is a key operation unit for inputting a telephone number and selecting a function, and 7 is compression / encoding (decompression / decoding) video data and audio data. A codec section, 8 is a telewriting control section for converting the data from the tablet 5 so that the data can be displayed on the monitor 2, 9 is a display control section for controlling switching of display of video on the monitor 2, and 10 is video and audio. , Tablet (telewriting) data to CCITT Recommendation H.264. 221 (from 64 kb / s in audiovisual teleservice to 1920
kb / s channel frame structure) or a multiplexing / separating unit that separates the frame sent from the other party into video, audio, and tablet data. 11 is based on the setting from the key operation unit 6. , A terminal control unit for controlling the entire terminal device, 12 a line interface unit for connecting the terminal to an integrated service digital network (ISDN) 20, and 13 a CCITT Recommendation H.264. 242 (1920
A bit rate allocation signal (BAS: Bit-ra) that executes a communication procedure based on a method of setting communication between audiovisual terminals using digital channels up to kb / s.
te Allocation Signal) control unit.

Further, FIG. 4 shows the CCITT Recommendation H.264. 22
1 is a diagram showing a multiplex frame structure defined in H. 1 in relation to time T. Table 1 below shows CCITT Recommendation H.264. 22 is a numerical table of BAS codes defined in 221.

[0006]

[Table 1]

The operation of the conventional image communication terminal device configured as described above will be described below.

When the telephone number of the other terminal is set by the key operation section 6 and the call key is pressed, the terminal control section 11 communicates with the other terminal via the line interface section 12 to the B-channel usable by the user on the ISDN 20. Make a connection. In ISDN 20, the D channel is used for switching connection. After the connection is completed, BAS control unit 13 using B channel
By CCITT Recommendation H. The mode initialization procedure is activated by the communication procedure based on 242. In this mode initialization procedure, first, frame synchronization is established by using a frame synchronization signal (FAS: Frame Aligment Signal) as shown in FIG. The terminal capability is exchanged with the partner terminal by using the transfer rate capability and the data / video capability. Then, the command BAS code is used to switch to an appropriate operation mode in consideration of the capabilities of the own terminal and the partner terminal.

A combination of two frames (a) and (a) in FIG. 4 is called a sub-multiframe (multiplexed frame structure), and BAS is represented by 8 bits of the first frame (a). It is composed of a BAS code and an error correction code represented by 8 bits of the second frame (a). Further, the switching of the operation mode becomes effective from the next sub-multiframe upon receiving the command BAS code.

FIG. 2A shows CC when two B channels are used.
ITT Recommendation H. An example of division within 221 frames is shown. At this time, in the first B channel, voice (A) is 16 kb / s, low speed data (LSD) is 40 kb / s, and video (V) is first B,
It is transmitted at 68.8 kb / s on the second B channel.

[0011]

However, in the above-mentioned conventional image communication terminal device, there are two areas that can be allocated for data using the BAS code, a low speed data area and a high speed data area. When it was necessary to send the coordinate data at the time of telewriting using, the accumulated still image data, the control data of the camera of the partner terminal, etc. at once, it could not be sent.

The high-speed data area can be used only when communicating with a plurality of B channels or H0 channels, but since it can only be allocated in units of 64 kb / s, 64
When data is transmitted at a low speed of less than kb / s, it is inefficient to allocate to data, and the transmission capacity of the entire communication is small.
(For example, during 2B transmission), there is a problem in that the area for sending video cannot be taken up.

In order to solve this, when the transmission rate of each data is low, it is possible to divide the low-speed data area or the high-speed data area into a plurality of areas, and use the BAS code defined in the recommendation. The procedure could not be realized.

The present invention solves the above problems,
The purpose is to be able to flexibly support various applications.

[0015]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention is directed to CCITT Recommendation H.264. Means for designating a sub-channel in a frame by using a BAS code not defined in 221; means for transmitting and receiving a bit rate allocation signal code indicating the designated sub-channel; and on the designated sub-channel, A means for dividing the frame, selecting transmission / reception data and transmission speed, and allocating a control signal for controlling the camera of the partner terminal, transmitting / receiving the signal, and exchanging with the partner terminal is provided. ..

[0016]

According to the present invention, when it becomes necessary to send still image data and tablet (telewriting) data at the same time while performing video and audio communication, B which is not defined in the recommendation
Two areas, low speed data and high speed data, are assigned by using the AS code to assign a code for controlling the frame division method, transmission / reception data and transmission speed selection, and the camera of the partner terminal on the designated sub-channel. It is possible to transmit two types of data in one of the low speed and high speed areas without using.

Further, when it becomes necessary to control the camera or the like of the partner terminal, the low speed / current transmission / reception of other data is in use.
B not defined in Recommendation without using high speed data area
This is possible by notifying the partner terminal using the area designated by the AS code.

[0018]

FIG. 1 is a functional block diagram of an image communication terminal device according to an embodiment of the present invention. 1 is a camera, 2 is a monitor, 3 is a microphone, 4 is a speaker, 5 is a tablet, and 6 is a key operation unit. , 7 is a codec section, 8 is a telewriting control section, 9 is a display control section, 10 is a multiplexing / demultiplexing section,
11 is a terminal control unit, 12 is a line interface unit, 13 is a BA
The S control unit has the same configuration as that of the conventional example.

Next, 14 is a scanner for taking in still picture data, 15 is a still picture control section for compressing / decompressing still picture data, and 16 is a partner terminal using an area specified by the BAS code which is undefined in the recommendation. , A remote control unit for controlling the camera, 17 is a data area division control unit for performing control for dividing the low speed data area and the high speed data area into a plurality of areas using an area specified by the BAS code which is not defined in the recommendation, and 18 is A data area multiplexing / demultiplexing section that divides the data area based on an instruction from the data area division control section 17 to multiplex / separate a plurality of data, 19
Is a control code transmission / reception unit that transmits / receives data in an area specified by a BAS code which is undefined in the recommendation.

Table 2 below is a numerical table of the BAS code newly defined in this embodiment. Table 3 below
6 is a numerical table of control codes used when controlling division of a data area and camera control of a partner terminal in the present embodiment.

[0021]

[Table 2]

[0022]

[Table 3]

The operation of the image communication terminal device configured as described above will be described below.

When communicating using two B channels,
A case where the low-speed data area is divided into two will be described. Currently, as shown in Fig. 2 (a), audio (A) is 16 kb / s, tablet data (low-speed data: LSD) is 40 kb / s, video
It is assumed that (V) is multiplexed at 68.8 kb / s and communicates with the other terminal.

At this time, let us consider a case where the still image data (SD) is sent using 32 kb / s in the low speed data area.

When the still image data transmission is selected from the key operation unit 6, the terminal control unit 11 detects it and notifies the data area division control unit 17 of it. In response to this, the data area division control unit 17 first sends a control code to the other terminal to the BAS control unit 13 in the portion of the 1B subchannel 3 of the data area (see Table 2).
BAS = (11
0) Instruct to send [3]. BAS that received this
The control unit 13 repeats the valid command BA
The transmission of the S code is stopped, and the BAS code instructed by the data area division control unit 17 is transmitted. At the same time, the data area division control unit 17 divides the low-speed data area into two in the partner terminal with respect to the control code transmission / reception unit 19 to obtain 32 kb / s of still image data.
The control codes (D ₀ , D ₁ , D ₂ D ₃ D ₄ , D ₅ D ₆ D ₇ ) = ( ₀ , ₀ , ₁₀₎ shown in Table 3 to notify that s is allocated.
50,000) to send. Here, it is assumed that the control codes (D ₀ to D ₇ ) are transmitted to the positions of octet 1 to octet 8 of the 1B subchannel 3.

Receiving this, the control code transmitting / receiving unit 19 sends the control code instructed by the data area division control unit 17 to the 1B sub-channel 3 in the next sub-multiframe. When the transmission of the designated control code is completed, the data area division control unit 17 is notified of the completion of transmission. The data area division control unit 17 having received the notification notifies the BAS control unit 13 of the completion of transmission, and the BAS control unit 13 having received the notification.
Repeatedly sends a valid command BAS code as before.

The data area division control unit 17, which has received the notification of the completion of transmission, informs the BAS control unit 13 first that it will stop using the 1B subchannel 3 for defining the control code for the other terminal. BAS = (1
10) Instruct to send [0]. As a result, the 1B sub-channel 3 can be used for data transmission / reception. At the same time, the data area division control unit 17
On the other hand, the low speed data area is allocated to the sub-channels # 3 to # 6 for still image data (SD) and the remaining sub-channel # 7 for tablet data (TD) as shown in FIG. 2B. Data area multiplexing / separation unit based on the instruction
Reference numeral 18 multiplexes still image data and tablet data into a low speed data area and sends the multiplexed data to the multiplexing / separating unit 10. The control code (D ₀ , D ₁ , D ₂ D ₃ D ₄ , D ₅ D ₆ D ₇ ) is applied by the multiplexer / demultiplexer 10.
= (0,0,100,000) is sent from the next sub-multiframe, tablet data is sent at 8 kb / s and still image data is sent at 32 kb / s to the partner terminal.

On the contrary, when the BAS control unit 13 detects the BAS code of BAS = (110) [3] in order to inform the partner terminal that the control code is defined in the 1B sub-channel 3 portion of the data area, the control code is The transmission / reception unit 19 notifies the data area division control unit 17 of the received control code. Upon receiving this, the data area division control unit 17 switches the data area multiplexing / demultiplexing unit 18 as instructed by the other terminal, and
It notifies the terminal control unit 11 to switch the internal operation.
The terminal control unit 11 controls the still image control unit 15 and the telewriting control unit 8 to prepare for the data sent from the next sub-multiframe.

When the key for zooming up the camera of the partner terminal is pressed, the terminal control unit 11 detects it and notifies the remote control unit 16 of it. Receiving it, the remote controller 16 is B
First, the AS control unit 13 is instructed to send BAS = (110) [3] in order to inform the partner terminal that the control code is defined in the 1B subchannel 3 portion of the data area. Accordingly, the BAS control unit 13 stops the transmission of the valid command BAS code which has been repeated until then, and transmits the BAS code instructed by the remote control unit 16. At the same time, the remote control unit 16 sends the control code transmitting / receiving unit 19 to the table 3
Control code (D ₀ , D ₁ , D ₂ D ₃ D ₄ , D ₅ D ₆ D ₇ ) =
Instruct to send (0, 1,000, 010).

Receiving this, the control code transmitting / receiving unit 19 sends the control code instructed by the remote control unit 16 onto the 1B sub-channel 3. When the transmission of the designated control code is completed, the remote control unit 16 is notified of the completion of transmission.
The remote control unit 16 that has received the notification notifies the BAS control unit 13 of the completion of transmission, and the BAS control unit 13 that has received the notification repeatedly transmits the valid BAS as before.

Upon receiving the notification of the completion of transmission, the remote controller 16
First, the AS controller 13 is instructed to send BAS = (110) [0] shown in Table 2 to notify the other terminal that the use of the 1B subchannel 3 for defining the control code is stopped. .. As a result, the 1B sub-channel 3 can be used for data transmission / reception.

On the contrary, the BAS control unit 13 detects the BAS code of BAS = (110) [3] shown in Table 2 in order to inform the partner terminal that the control code is defined in the 1B sub-channel 3 portion of the data area. Then, if the received control code is related to camera control,
Notify the remote control unit 16. The remote control unit 16 having received the instruction analyzes the control code and instructs the terminal control unit 11 to control the camera based on the instruction from the partner terminal. Then, the terminal control unit 11 having received the control controls the movement of the camera of the own terminal.

In the above embodiment, the data area is divided into two and the control of the partner camera is only performed. However, various control codes are defined in the area specified by the BAS code which is undefined in the recommendation according to the application. Fine control is possible.

[0035]

As described above, the image communication terminal device according to the present invention is capable of implementing the multiplexing control function based on the CCITT recommendation only by adding simple hardware and a control procedure to the camera of the other terminal. The information that controls the data area can be sent without using a constant data area, and the data area can be easily divided into multiple areas of arbitrary size for effective use of the data area. It can flexibly support various applications.

[Brief description of drawings]

FIG. 1 is a functional block diagram of an image communication terminal device according to an embodiment of the present invention.

FIG. 2 CC when communicating using two B channels
ITT Recommendation H. It is a figure showing the example of division in 221 frames.

FIG. 3 is a functional block diagram of a conventional image communication terminal device.

FIG. 4 CCITT Recommendation H. FIG. 22 is a diagram showing a multiplexing frame structure defined by H.221 in relation to time T.

[Explanation of symbols]

1 ... Camera, 2 ... Monitor, 3 ... Microphone, 4
... speaker, 5 ... tablet, 6 ... key operation part,
7 ... Codec section, 8 ... Telewriting control section,
9 ... Display control unit, 10 ... Multiplexing / separating unit, 11 ... Terminal control unit, 12 ... Line interface unit, 13 ... BAS control unit, 14 ... Scanner, 15 ... Still image control unit, 16 ... Remote control unit, 17 ... Data area division control unit, 18 ... Data area multiplexing / demultiplexing unit, 19 ... Control code transmitting / receiving unit, 20 ... ISD
N.

Claims (1)

[Claims] Claim 1: International Telegraph and Telephone Consultative Committee Recommendation H. 221
In the image communication terminal device having the function of multiplex transmission of video, audio and data according to the above, the International Telegraph and Telephone Advisory Committee Recommendation H. 221, means for designating a sub-channel in a frame using a bit rate allocation signal code not defined by H.221, means for transmitting / receiving a bit rate allocation signal code indicating the designated sub channel, and the specified sub channel The above is provided with means for dividing a frame, selecting transmission / reception data and transmission speed, and allocating a control signal for controlling a camera or the like of a partner terminal, transmitting / receiving it and exchanging it with the partner terminal. An image communication terminal device characterized by the above.