JPH08186807A - Video conference communication terminal equipment - Google Patents

Abstract

PURPOSE: To attain the communication by providing plural motion image signal output means, a multiplex moving image CODEC means, a video monitor means and a transmission control means which are specific means respectively to the terminal equipment so as to multiplex plural video sources. CONSTITUTION: The terminal equipment is made up of a system control section 1, a ROM 2, a RAM 3, a clock circuit 4, an image processing section 5, a magnetic disk device 6, an operation display section 7, a voice CODEC 9, an audio control section 10, a multiplexing video CODEC 15, display control sections 16, 17, a video camera control section 18, a D-channel transmission control section 20, and a multiplexer/demultiplexer section 21 or the like. That is, the terminal equipment is provided with a communication function of sound information, a communication function of moving image information, a telewriting function, and a multiplexing communication function for the communication functions above and also with two sets of video camera equipments 11, 12, and video monitors 13, 14, that is, a function of multiplexing, communicating two systems of moving image information and displaying the result. Thus, plural motion image signals using plural video sources are multiplexed and the multiplexed signal is sent/received by one transmission means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video conference communication terminal device having at least a communication function for exchanging voice information and moving image information.

[0002]

2. Description of the Related Art Generally, as a coding method for coding and compressing a moving picture signal in a video conference communication terminal apparatus having at least a communication function for exchanging voice information and moving picture information, for example, TTC standard JT-H. Intra-frame encoding processing for encoding all images for one frame and inter-frame encoding for forming and encoding a difference (or prediction error) between images between frames as in the encoding method of H.261. A highly efficient coding method for performing processing to code and compress a moving image signal is used.

By the way, in such an encoding method, since basically only one system of moving image signals is encoded and compressed, for example, in a video conference communication terminal device, an image of a main camera device and an image of a sub camera device are displayed. When trying to transmit to the partner terminal, it is necessary to switch between the moving image signal output from the main camera device and the moving image signal output from the sub camera device, which may cause a situation in which the conference session cannot proceed smoothly.

As described above, in order to use a plurality of video sources, for example, a plurality of conference communications are executed in parallel,
It is possible to use the main camera device as a video source in one conference communication call and use the sub camera device as a video source in the other conference communication call. Alternatively, it is conceivable that the transmitting side forms a moving image signal that combines the moving image signal of the main camera device and the moving image signal of the sub camera device, and transmits the combined moving image signal.

[0005]

However, the former method requires a plurality of lines and thus requires a large amount of communication equipment, which may cause a problem that the device cost and the communication cost increase. Conceivable.

Further, in the latter method, it is impossible for the receiving side to separate the moving image signal for each image source, which may deteriorate the usability of the apparatus.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a video conference communication terminal device capable of multiplexing and communicating a plurality of video sources.

[0008]

The present invention provides a plurality of moving picture signal output means for outputting a plurality of moving picture signals in a video conference communication terminal device having at least a communication function for exchanging voice information and moving picture information. Multiplexed moving image CODEC for inputting a plurality of moving image signals output from a plurality of moving image signal output means and respectively performing multiplex processing of encoding processing corresponding to each moving image signal and decoding processing of the encoded moving image signal. Means, a video monitor means for displaying an image of the decoded moving picture signal outputted from the multiplexed moving picture CODEC means, and a moving picture signal multiplexing ability is exchanged with the other terminal prior to the start of the video conference communication. According to the exchanged multiplexing capability, transmission control means for controlling the multiplexing processing of the multiplexed moving image CODEC means during the video conference communication operation is provided. It is.

Further, the multiplexed moving image CODEC means is
An intra-frame encoding process for encoding all images for one frame and an inter-frame encoding process for forming and encoding an image difference between frames are performed to encode and compress a moving image signal. A moving picture input means for switching and inputting the plurality of moving picture signals, a common coding means for coding and compressing a moving picture signal input via the moving picture input means, and a code formed by the coding means for decoding Decoding means, a plurality of image memory means for storing the decoded moving image signal formed by the decoding means for one frame for each of the plurality of moving image signals, and an intra-frame code for each of the plurality of moving image signals. When performing the encoding process, the moving image signal input from the moving image input means is encoded and compressed by the encoding means to form encoded information, and each of the plurality of moving image signals is processed. When inter-frame coding, to form the difference of the plurality of images and decoding video signals corresponding to each of the video signals read out from the memory means, each of the video signal inputted from the video input means,
Encoding control is performed to encode the moving image signal of the difference by the encoding means to form encoded information, while adding the identification information for identifying each of the plurality of moving image signals to each encoded information. It is equipped with means.

Further, the encoding control means is adapted to switch the plurality of moving image signals at predetermined time intervals and in frame units. Further, the encoding control means switches the plurality of moving image signals for each predetermined number of frames.

The multiplexed moving image CODEC means is
For each of a plurality of moving image signals, a decoding unit that performs an inverse transformation of the encoding unit to decode the encoded information to form a decoded moving image signal, and a decoded moving image signal formed by the decoding unit Based on the plurality of image memory means for storing one frame and the identification information added to the encoded information to be decoded, the encoding processing mode of each moving image signal is identified, and the identification information is the intra-frame code. When the encoding processing is represented, the encoding information relating to the moving image signal is decoded by the decoding means, the decoded moving image signal obtained thereby is output as an output decoded moving image signal, and the corresponding plurality of image memory means are provided. When the identification information encoded information represents interframe encoding processing, the encoded information related to the moving image signal is decoded. Decoding by the means, the decoded moving picture signal corresponding to the moving picture signal is read from the image memory means, and the result of adding the read decoded moving picture signal and the moving picture signal output from the decoding means is output and decoded. This is provided with a decoding control means for outputting as a converted moving image signal.

[0012]

Therefore, since a plurality of video signals from a plurality of video sources can be multiplexed and exchanged by one transmission means, a video conference communication session applying a plurality of video sources can be realized inexpensively and appropriately. can do.

[0013]

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

FIG. 1 shows a video conference communication terminal device according to an embodiment of the present invention. This video conference communication terminal device uses a basic interface of ISDN as a transmission path, and is provided with a voice information communication function, a moving image information communication function, a telewriting function, and a multiplexing communication function of these communication functions. Also, data communication using two information channels (B channels) is possible by connecting to the ISDN basic interface. Further, each of the two video camera devices and the video monitor device is provided, and the video information of two systems is multiplexed and communicated and displayed.

In FIG. 1, the system control unit 1 controls the respective units of the video conference communication terminal device, processes of upper layers of the video conference communication, and various application programs provided in the video conference communication terminal device. The ROM (Read Only Memory) 2 is necessary for executing a part of the control processing program executed by the system control unit 1 and for executing the control processing program. RAM (random access memory) 3 constitutes a work area of the system control unit 1 and the like.

The clock circuit 4 is for outputting the current date and time information, and the image processing section 5 is for performing various image processing such as image data scaling processing and resolution conversion processing, and the magnetic disk. The device 6 is for storing system software, a plurality of application programs, a large number of user data, and the like, and the operation display unit 7 is for a user to operate the video conference communication terminal device. .

The voice input / output device 8 is for inputting a voice for a call with a microphone and outputting it with a speaker. An analog voice signal input from the voice input / output device 8 with a microphone is output to a voice CODEC 9, and , The analog audio signal output from the audio input / output device 8 through the speaker is
It is output from the audio CODEC 9 and added to the audio input / output device 8.

The audio CODEC 9 is for performing signal conversion processing of analog signal / digital data for transmitting an analog audio signal using the B channel of ISDN. Further, the voice control unit 10 includes the voice input / output device 8
Is for controlling the operation of.

The video camera devices 11 and 12 are for taking images of the user side of the video conference communication terminal device, and the video monitor devices 13 and 14 independently display the video outputs of two systems. It is for.

The two moving image signals output from the video camera devices 11 and 12 are applied to the video signal input terminal of the multiplexed video CODEC 15 and the display control unit 1 is also provided.
It is added to the video signal input terminals 6 and 17. The video camera control unit 18 is for controlling operations such as shooting on / off, zooming in / zooming out, and panning of the video camera devices 11 and 12.

The multiplexed video CODEC 15 receives the moving image signals input from the video camera devices 11 and 12 from the TTC standard JT-H. The multiplex moving image information is encoded and compressed by the H.261 coding system, and the multiplex moving image information in the encoded and compressed state is separated for each video source to obtain the moving image information for each video source. It is for decoding and converting it into the original moving image signal.

The display control units 16 and 17 control the display contents of the screens displayed on the video monitor devices 13 and 14, respectively.
Display screen information of moving image signals input from the video camera devices 11 and 12 and display screen information of the received moving image signal of the multiplexed video CODEC 15 are formed, and the display screen information is appropriately combined, and each is a video monitor device. The display screens 13 and 14 are configured.

The ISDN interface circuit 19 is an IS
In addition to being connected to the DN, it is equipped with the layer 1 signal processing function of the ISDN basic interface and the integration / separation function of the D channel signal and the two B channel signals. The D channel signal is D channel transmission control. Part 20
In addition, the signals of the two B channels are exchanged with the multiplexer / demultiplexer 21.

The D channel transmission control unit 20 has a layer 2 signal processing function of the D channel and a call control processing function for connecting / disconnecting one or two B channels.

The multiplexer / demultiplexer 21 multiplexes data of a plurality of media such as voice, moving images, and general-purpose data (other data such as telewriting data) exchanged using the B channel, and the TTC standard JT. −
H. The frame data defined in 221 is formed and transmitted to the line side, and the data of a plurality of media multiplexed in the received frame data is separated. The multiplexer / demultiplexer 21 exchanges audio data with the audio CODEC 9, exchanges moving image data with the multiplexed video CODEC 15, and
General-purpose data is exchanged with the system control unit 1.

These system control unit 1, ROM 2 and R
AM3, clock circuit 4, image processing unit 5, magnetic disk device 6, operation display unit 7, audio CODEC 9, audio control unit 1
0, multiplexed video CODEC 15, display control units 16 and 1
7, video camera control unit 18, D channel transmission control unit 2
0 and the multiplexer / demultiplexer 21 are connected to the internal bus 21, and data exchange between these respective elements is mainly performed via the internal bus 22.

FIG. 2 shows a structural example of the main part of the multiplexed video CODEC 15. In the following description, a system having an encoding / decoding function for n-system video signals is described, but in this embodiment, the encoding / decoding function for two-system video signals is used. ing.

In the figure, n video input signals VI
1 to VIn have been added to the source encoder 25. The information source encoder 25 has the video input signals VI1 to VI1.
While switching VIn at a predetermined timing, the TTC standard JT-H. The information source coding process of the coding system of H.261 is executed, and its output signal is added to the video signal multiplexing encoder 26.

The video signal multiplexing encoder 26 corresponds to the n video input signals VI1 to VIn, and is a TTC standard JT.
-H. Code data of the H.261 coding system, and the output signal thereof is output to the external device via the output buffer 3 as the multiplexed moving image code data VCa.

The control unit 28 controls the operations of the information source encoder 25 and the video signal multiplex encoder 26 so that the video input signals VI1 to VIn are encoded.

From the output buffer 27, the control unit 2
8 is notified of information such as the code amount, and the control unit 28
On the basis of the information added from the output buffer 27, the information source encoder 25 and the video signal multiplexing encoder 2
The operation of 6 may be controlled.

The memory 29 also stores the video input signal VI.
Information that serves as a reference for switching control of 1 to VIn and the like is stored. Further, the contents stored in the memory 29 can be appropriately referred to / rewritten by the system controller 1.

Further, the input buffer 30 is a multiplexed moving image code data V containing code information of a plurality of video sources.
Cb is input, and the input data is added to the video signal multiplex decoder 31.

The video signal multiplex decoder 31 receives the TTC standard J for each of the code information of a plurality of video sources.
T-H. It performs a decoding process of the H.261 coding system, and its output signal is added to the information source decoder 32.

The information source decoder 32 determines the TTC standard JT-H.264 for the coded data of each video source. 26
Which performs the information source decoding process of the encoding method of 1.
The information decoder 8 outputs n video output signals VO1.
~ VOn is output.

Now, the TTC standard JT-H. The moving picture coding method of H.261 will be described next.

First, the TTC standard JT-H. In the H.261 moving image coding system, CIF and QCIF are used as moving image information.
There are two types of formats defined.

CIF (Common Intermed)
The iate Format (Common Intermediate Format) format is a basic format of moving image information, and is a CIF.
Displays a screen of 29.97 frames per second, and for the luminance component (Y), one frame (image frame) is composed of 288 lines, one line is composed of 360 pixels, and the color difference component ( For Cb and Cr), one frame is made up of 144 lines and one line is made up of 180 pixels.

Then, as shown in FIG. 3A, the frame is divided into 12 GOBs (Group Of Blocks).
k), and each GOB is divided into 33 macroblocks of 11 × 3 as shown in FIG.

Further, as shown in FIG. 7C, one macroblock has 2 × 2 4 pixels for the luminance component.
The color difference component is divided into 1 × 1 blocks. Therefore, each block of the luminance component and the color difference component is composed of 8 pixels × 8 lines, as shown in FIG.

QCIF (Quater CIF)
Is a format in which the number of pixels is set to 1/4 of CIF as shown in FIG. In addition, TTC standard JT-H.
261 stipulates that the moving image CODEC needs to handle at least QCIF.
When F and QCIF face each other, it is specified to communicate by QCIF.

This moving picture information corresponds to the hierarchical structure of frame / GOB / macroblock / block as described above, an example of which is shown in FIGS. The moving picture information is formed by the video signal multiplexing encoder 26.

First, the moving picture information of one frame is, as shown in FIG. 9A, a frame start code PSC consisting of 20-bit data of a predetermined bit pattern representing the start of the frame, and a frame number TR representing the sequence number of the frame. , Type information PTYPE that represents information about the entire frame, 1-bit extension data insertion information PE
I, 1-byte preliminary information PSPARE, and GOB
It consists of data. Here, the extension data insertion information PEI
May include at least one and the preliminary information PSPARE may not be included. Also, the frame start code PSC,
The frame number TR, the type information PTYPE, the extension data insertion information PEI, and the preliminary information PSPARE are
Called the frame header.

One GOB data is arranged for each GOB. One GOB data indicates the start of GOB data, as shown in FIG.
OB start code GBSC, GOB number GN indicating the position of GOB, and quantization characteristic information GQUA indicating information on the quantization characteristic.
NT, extension data insertion information GEI indicating presence / absence of extension data area (preliminary information), preliminary information GSPARE, and macroblock data. Here, the extension data insertion information GEI may include at least one and the preliminary information GSPARE may not be included. Also, GOB
Start code GBSC, GOB number GN, quantization characteristic information G
QUANT, extension data insertion information GEI, and spare information GSPARE are called GOB headers.

One macroblock data is arranged for each macroblock. However, if there is no information in that part of the frame, it will not be transmitted.

One macroblock data is, as shown in FIG. 6C, a macroblock address MBA for indicating the position of the macroblock, a type of the macroblock, and a type for indicating which data element appears. Information MTYPE, quantization characteristic information MQUANT representing the quantization characteristic, motion vector information MV
D, a significant block pattern CB representing that it is a macroblock in which at least one transform coefficient is transmitted
It consists of P and block data. Here, the quantization characteristic MQUANT, the motion vector information MVD, and the significant block pattern CBP appear when instructed by the type information MTYPE. Also, the macro block address MBA, the type information MTYPE, the quantization characteristic information M
QUANT, motion vector information MVD, and significant block pattern CBP are called macroblock headers.

As shown in FIG. 7D, the block data is, for example, a transform coefficient TCOEFF representing transform coefficient data obtained by performing DCT (discrete cosine transform) processing on the image data of the block, and a block coefficient. It is composed of a block end code EOB indicating the end.

The encoding process is executed in macroblock units.

In the present embodiment, as described above, n
Since each video source is encoded as a separate system, it is necessary to be able to identify each video source. Therefore, in this embodiment, by setting "1" in the extension data insertion information PEI and setting the identification number of the video source in the preliminary information PSPARE, the code data can be identified for each video source. To do.

Here, the TTC standard JT-H. According to H.261, at present, the usage of the preliminary information PSPARE is not defined, and therefore, when the value of the extension data insertion information PEI is “1”, the decoding device determines that the preliminary information PSPARE is used.
We advise you to discard the ARE. In this embodiment, by using this preliminary information PSPARE, multiplexing of video sources can be realized.

Further, the video signal multiplex decoder 31 according to the present embodiment uses the extension data insertion information PEI of the moving image information.
For the data of the frame in which the value of is set to "1", the content of the video source identification information set in the preliminary information PSPARE is determined to determine which video source the data of the frame belongs to. Judge,
The determination result is notified to the information source decoder 32.

Accordingly, the information source decoder 32 determines which video source the data of the frame input at that time belongs to, decodes the corresponding video source, and outputs the corresponding video output. Signals VO1 to VOn
And output.

FIG. 6 shows an example of the information source encoder 1.

In the figure, the selector SL1 switches the n video input signals VI1 to VIn based on the control signal S1 output from the control section 28.
The switching output is the subtracter D as the video input signal VI.
F, one switch input terminal of the switch SW1, and the common input terminal of the selector SL4.

The switch SW1 switches the output of the subtractor DF or the video input signal VI on the basis of the control signal S2 applied from the control section 28, and its output is applied to the converter CVa. There is. Converter CVa
Of the TTC standard JT-H. 261 performs the two-dimensional DCT conversion process, and the output signal is the quantizer QZa.
Has been added to.

The quantizer QZa performs a predetermined quantization process on the input signal according to the quantization step value Sq added from the control unit 28, and the output signal thereof is the source code data VSa. Is added to the video signal multiplex encoder 2 as well as to the inverse quantizer IQZa.

The inverse quantizer IQZa performs an inverse quantization process, which is an inverse transform process of the quantizer QZa, on the information source code data VSa according to the quantization step value Sq added from the control unit 28. And its output signal is
It is added to the inverse converter ICVa.

The inverse converter ICVa performs the inverse conversion process of the converter CVa, and therefore, the inverse converter ICVa.
Although the output signal of a includes the quantization error of the quantizer QZa, it becomes a signal (hereinafter referred to as a decoded video signal) corresponding to the video input signal VI input to the converter CVa. The decoded video signal output from the inverse converter ICVa is added to the adder SMa.

The output of the adder SMa is added to the common connection terminal of the selector SL2, and n of the selector SL2 is added.
The output signals from the output terminals are respectively the image memory MP.
a1 to Mpan.

In addition, the video input signals VI1 to VI1 are sent to the image memories MPa1 to MPan via the selector SL4.
VIn has been added. Image memory MPa1 to MPa
n is an image memory having a variable delay function for motion compensation, which stores a decoded video signal for one frame in macroblock units and predicts the video signal of the next frame based on the decoded video signal. , A motion vector is detected based on the decoded video signal and the video input signals VI1 to VIn. The motion vector signals SV1 to SVn corresponding to the detected motion vector are added to the video signal multiplexing encoder 26.

The predicted video signals output from the image memories MPa1 to Mpan are applied to the switching connection terminal of the selector SL3. The output signal of the common connection end of the selector SL3 is added to the switch SW2 and the subtractor DF via the in-loop filter FLa.

Here, the selector SL2 and the selector SL3
The selector SL4 performs the switching operation in conjunction with the selector SL1, and the switch SW2 performs the switching operation in conjunction with the switch SW1.

When the video input signal VI1 is encoded with the above configuration, the control unit 28 firstly selects the selectors SL1 and SL1.
Video input signal VI1 by SL2, SL3, SL4
Select the switching connection end corresponding to.

When each intra-frame coding process (INTRA mode) is performed in this state, the control section 28
The switching devices SW1 and SW2 are switched and connected to the states shown by the broken lines in the figure. As a result, the video input signal VI1 input through the selector SL1 is subjected to the two-dimensional DCT conversion process by the converter CVa, and then quantized by the quantizer QZa, so that the video signal multiplex encoder 26 receives the information source. It is output as coded data VSa.

Along with this, the source code data V
Sa is inversely quantized and converted by the inverse quantizer IQZa,
Further, the inverse converter ICVa performs a two-dimensional DCT inverse conversion process, and the decoded video signal is added to the image memory MPa1 via the adder SMa and the selector SL2 and stored.

Next, the interframe coding process (INTER
Mode), the control unit 28 controls the switch SW1, S1.
Each W2 is switched and connected to the state shown by the solid line in the figure. As a result, the decoded video signal output from the image memory MPa1 passes through the selector SL3 and the in-loop filter FL.
After passing through a, it is added to the subtractor DF and
It is added to the adder SMa via the switch SW2.

Therefore, after that, the difference value between the video input signal VI1 and the predicted value of the next frame output from the image memory MPa1 is converted into a two-dimensional D value by the converter CVa.
After the CT conversion processing, the quantization processing is performed by the quantizer QZa and is output to the video signal multiplex encoder 2 as the information source code data VSa.

Along with this, the source code data V
Sa is inversely quantized and converted by the inverse quantizer IQZa,
Further, the inverse converter ICVa performs a two-dimensional DCT inverse conversion process, and the decoded video signal is added to the image memory MPa1 via the adder SMa and the selector SL2 and stored.

This operation is sequentially repeated to form the source code data for the video signal VI1.

When the other video signals VI2 to VIn are coded, the control section 28 selects the selector SL.
The same operation as described above is performed with the switching connection terminals corresponding to the selected video input signals VI2 to VIn being selected by 1, SL2, SL3 and SL4.

Further, when the above-mentioned encoding processing operation is performed, the control unit 28 outputs various signals representing respective states to the video signal multiplex encoder 26. That is, the control unit 28 controls the encoding mode (INTRA mode /
Identification flag signal S for identifying the INTER mode)
P, a transmission / non-transmission flag signal St for designating whether or not to transmit the frame, a video source identification signal Sbn for identifying the video input signals VI1 to VIn being encoded at that time, and a quantum. Conversion step value Sq
Is output to the video signal multiplexing encoder 2. The in-loop filter FLa is turned on / off according to the operation setting of this device. The in-loop filter FLa uses the video signal multiplex encoder 26 to output the signal Sf indicating the on / off operation.
Is output to.

As a result, the video signal multiplexing encoder 26
Is the source code data VSa input at that time and the video source numbers of the valid motion vector signals SV1 to SVn, the coding mode discrimination, and the in-loop filter FL.
Knowing the on / off state of a, the code information as described above is formed.

FIG. 7 shows an example of the information source decoder 8.

In the figure, the inverse quantizer IQZb outputs the source code data VSb output from the video signal multiplex decoder 31 according to the quantization step value SSq output from the video signal multiplex decoder 31. Information source encoder 1
Inverse quantization processing, which is the inverse conversion processing of the quantizer QZa, is performed, and its output signal is the inverse converter ICVb.
Has been added to.

The inverse converter ICVb performs an inverse conversion process of the converter CVa of the information source encoder 25, and its output signal is passed through the adder SMb as the video output signal VO to the selectors SL11 and SL12. Has been added to the common connection end of.

Output signals from the n output terminals of the selector SL2 are applied to the image memories MPb1 to MPbn, respectively. In addition, the image memories MPb1 to MPbn
Are added with motion vector signals SSV1 to SSVn from the video signal multiplexing decoder 7, respectively.

The image memories MPb1 to MPbn are image memories having a variable delay function for motion compensation, and store a decoded video signal for one frame in macroblock units,
The decoded video signal and motion vector signal SSV1
~ The video signal of the next frame is predicted based on SSVn.

The predicted video signals output from the image memories MPb1 to MPbn are applied to the switching connection terminal of the selector SL13. The output signal of the common connection end of the selector SL3 is passed through the in-loop filter FLa and is output to the switch SW1.
One of the switching input terminals is added to one. Switch SW1
The output of the common connection terminal of 1 is added to the adder SMb.

Here, the selector SL11 and the selector SL
12 and the selector SL13 perform a switching operation in conjunction with each other, and the switching operation is controlled by the video source switching signal SSb output from the video signal multiplexing decoder 7. The switching operation of the switch SW1 is performed by the encoding mode (INT) output from the video signal multiplex decoder 7.
It is controlled by an identification flag signal SSP for identifying the RA mode / INTER mode).

With the above configuration, the video signal multiplexing decoder 3
1 determines the content of the video source identification information set in the preliminary information PSPARE for the data of the frame in which the value of the extension data insertion information PEI of the multiplexed moving image coded data VCb is set to "1". , And outputs the video source switching signal SSb corresponding to the contents. As a result, the selectors SL11, SL12, SL13 are
The switching connection end corresponding to the video source indicated by the video source switching signal SSb is selected.

In this state, when decoding the INTRA mode code data, the video signal multiplex decoder 31 is used.
Is an identification flag signal S having a value corresponding to the INTRA mode.
SP is output, whereby the switch SW11 is switched and connected to the state shown by the broken line in FIG.

Therefore, in this case, the information source code data VSb output from the video signal multiplex decoder 31.
Is inversely quantized by the inverse quantizer IQZa, and is further subjected to two-dimensional DCT inverse transformation by the inverse transformer ICVb. The output signal of the inverse transformer ICVb is output as the video output signal VO through the adder SMb. The video output signal VO is output as a video output signal VO1 via the selector SL11. Further, this video output signal VO is sent through the selector SL12 to the image memory MPb1.
Is added to and saved.

Next, when decoding the coded data in the INTER mode, the video signal multiplexing decoder 31
The identification flag signal SSP having a value corresponding to the NTER mode is output, whereby the switch SW11 is switched and connected to the state shown by the solid line in FIG. Also, the video signal multiplex encoder 7
Outputs a filter on / off signal SSf corresponding to the code data at that time, and thereby the in-loop filter F
Lb is turned on / off according to the content of the code data.

As a result, the video output signal output from the image memory MPb1 passes through the selector SL13,
After passing through the in-loop filter FLb, the switch SW1
It is added to the adder SMb via 1.

Therefore, after that, the inverse converter ICV
The value obtained by adding the signal corresponding to the prediction difference output from b and the prediction value of the next frame output from the image memory MPb1 is added as the video output signal VO to the adder SMb.
This video output signal VO is output from the selector S.
It is output as a video output signal VO1 via L11 and is also added to and saved in the image memory MPb1.

This operation is sequentially repeated to form and output the video output signal VO1.

When another video source number is designated, the selector SL11, SL12, SL13 selects the corresponding switching connection end of the video source, and the same operation as described above is performed.

The selection of the video source numbers (video input signals VI1 to VIn) can be performed at a predetermined time and in a frame unit. In that case, as shown in FIG. 7, a timer table for each video source that stores a timer value that specifies a switching time for each video source number is used. The timer table for each video source is stored in the memory 29 from an external device.

Therefore, in this case, as shown in FIG.
As shown in (b), during the period until the timed value of the system timer that measures a predetermined time matches the timer value stored corresponding to each video source number, the video input corresponding to that video source number is input. The signals VI1 to VIn are encoded.

FIG. 10 shows an example of the video source switching process executed by the control unit 28 in this case.

First, the system timer TS is cleared (process 101), and the process waits until the process for one frame is completed (NO loop of decision 102). When the processing for one frame is completed and the result of determination 102 is YES, the timer value TV corresponding to the video source is retrieved by referring to the timer table for each video source stored in the memory 5 (processing 103), The value of the system timer TS is the timer value T
Check if it is larger than V (decision 10
4).

When the result of determination 104 is NO,
Returning to the determination 102, the encoding process of the same video source is executed. When the result of determination 104 is YES, the video source is switched to the next video source (processing 105),
It is checked if the corresponding video input signal can be detected (decision 106). When the result of determination 106 is NO, the process returns to step 105 and another video source is tried.

When the result of determination 106 is YES, the system timer TS is cleared (process 107), the process returns to determination 102, and the process for the newly selected video source is performed.

Here, it is not necessary to set the same value for all video source numbers as the timer value in the timer table for each video source. For example, when the amount of coded data to be formed is large, the image quality of the reproduced image of the video source can be improved by increasing the timer value.
Also, an appropriate value can be set depending on the type of video source. For example, a minimum value can be set as a timer value for a video source that shoots a video that does not move much like a still image.

Further, as shown in FIG. 11, it is also possible to use a cumulative frame value table for each video source which stores a cumulative frame value representing the number of frames to be coded continuously for each video source number. The cumulative frame value table for each video source is stored in the memory 29.

In this case, as shown in FIGS. 12 (a) and 12 (b), the number of frames to be continuously coded matches the accumulated frame value stored corresponding to each video source number. During the period up to, the video input signals VI1 to VIn corresponding to the video source number are encoded.

FIG. 13 shows an example of the video source switching process executed by the control unit 28 in this case.

First, the value of the counter LS is initialized to 0 (process 201), and the process waits until the process for one frame is completed (NO loop of decision 202). When the processing for one frame ends and the result of the determination 202 is YES,
The value of the counter LS is incremented by 1 (process 203), the cumulative frame value LA for each video source is referenced by referring to the cumulative frame value table for each video source stored in the memory 5.
Is taken out (process 204), and it is checked whether the value of the counter LS is larger than the cumulative frame value LA (decision 205).

When the result of judgment 205 is NO,
Returning to the judgment 202, the encoding process of the same video source is executed. When the result of the determination 205 is YES, the video source is switched to the next video source (process 206),
It is checked whether the corresponding video input signal can be detected (decision 207). When the result of the determination 207 is NO, the process returns to the process 206 and another video source is tried.

When the result of the judgment 207 is YES, the value of the counter LS is initialized to 0 (process 20).
8) Then, the process returns to decision 202 and the process for the newly selected video source is performed.

Here, it is not necessary to set the same value for all video source numbers as the cumulative frame value of the video source-specific cumulative frame value table. For example, when the data amount of the code data to be formed is large, the image quality of the reproduced image of the video source can be improved by increasing the cumulative frame value. Also, an appropriate value can be set depending on the type of video source. For example, a minimum value can be set as a cumulative frame value for a video source that shoots a video that does not move much like a still image.

Considering the coding mode, INTR
The amount of code data by the A mode encoding process is INTE
It is expected that it will be larger than the code data amount by the R mode encoding process.

FIG. 14 shows an example of the video source switching process utilizing such a relationship.

First, one of the video sources is selected (process 301) and it is checked whether the corresponding video input signal can be detected (decision 302). When the result of determination 302 is NO, the process returns to step 301 and another video source is tried.

When the result of decision 302 is YES, it is checked whether the encoding mode at that time is the INTRA mode (decision 303), and the result of decision 303 is Y.
When ES, the predetermined value KA is set in the variable SA (process 304), and when the result of the judgment 303 is NO, the predetermined value KB is set in the variable SA (process 30).
5).

Then, the process waits until the processing for one frame is completed (NO loop of decision 306). When the processing for one frame is completed and the result of the determination 306 is YES, the value of the variable SA is decremented by 1 (processing 307) and the variable S is changed.
Check whether the value of A becomes "0" (decision 30
8) If the result of decision 308 is NO, then decision 3
Returning to 06, the same video source encoding process is executed.

When the result of determination 308 is YES, the process returns to step 301 and the next video source is tried.

Further, the values of the respective elements of the above-mentioned video source-specific timer value table and video source-specific cumulative frame value table can be changed stepwise according to the value of the motion vector signal.

In addition, the quantization step value and the CIF / QCIF moving image format may be defined depending on the type of video source. Therefore, for example, a video source quantization step value table showing the relationship between the video source number and the quantization step value, and a video source format table showing the relationship between the video source number and the CIF / QCIF image format type Are stored in the memory 29, and the control unit 28 may set the quantization step value and the image format type in the information source encoder 25 in accordance with each video source number.

Now, in the video conference communication terminal device, in the B channel, the TTC standard JT-H. Data is exchanged in the multi-frame format defined by 221.

As shown in FIG. 15, one multi-frame MFL includes eight sub-multi-frames SMF1 to SM.
F8, each sub-multiframe SMF1
Each SMF8 is composed of two frames. That is, one multi-frame MFL has 16
Each frame FLM0 to FLM15.

Each frame FLM0 to FLM15
As shown in FIG. 16, it consists of data of 80 octets, and the respective bit positions in which these octets are arranged in bit order form subchannels SCH1 to SCH8.

The eighth bit of the first octet to the eighth octet is the frame synchronization signal (Frame Ali).
The 8th bit of the 9th octet to the 16th octet constitutes a bit rate allocation signal (Bit rate Allocation).
Signal) BAS. That is, the sub-channel SCH8 is assigned to the eighth bit of the 17th octet to the 80th octet, and this portion is applied to the application channel AC (Application Channel).
el) is sometimes called. Also, sub-channel SC
In the 17th to 24th octets of H8, data of an encrypted channel for exchanging key information for encrypting data may be set (optional).

In this way, the frame synchronization signal FAS
8 bits are arranged in one frame FLM0 to FLM15, and the bit allocation is configured in units of multi-frame MFL as shown in FIG.

That is, even frames FLM0, FLM
2, ..., The second to eighth octets of the FLM 14, and the odd frames FLM1, FLM3 ,.
A horizontal synchronization signal composed of an 8-bit data pattern "001101111" is arranged in the FLM 15, and a vertical synchronization composed of a 6-bit data pattern "001011" is arranged in the first octet of the odd-numbered frames FLM1, FLM3, ..., FLM11. A sync signal is placed.

By detecting the horizontal synchronizing signal and the vertical synchronizing signal, it is possible to detect the synchronization of one multi-frame MFL.

The 0th frame, the 2nd frame, the 4th frame
Bits N1, N2, N3, N4, N5 of the first octet of the frame, the sixth frame and the eighth frame are used to indicate the multi-frame number. Of these, the bit N5 is used to indicate whether or not the multiframe number is used. In this way, since the data used for the multi-frame number is 4 bits, the multi-frame number changes in descending order with a value of 0 to 15, and the same multi-frame number appears every 16 multi-frames.

The tenth frame, the twelfth frame,
And bit L of the 1st octet of the 13th frame
1, L2, L3 are used to display the connection number indicating the order in which the B channels carrying the frame among the currently used B channels are connected. Also, the bit R of the first octet of the fifteenth frame is reserved (reserved) for future recommendation,
The value is set to 0.

The bit TEA of the first octet of the 14th frame is used to indicate that data transmission is impossible due to an internal failure of the data terminal device.

Also, odd-numbered frames FLM1, FLM3
.., bit A of the third octet of the FLM 15 is used to indicate whether frame synchronization or multi-frame synchronization is established or out of synchronization.

Also, odd-numbered frames FLM1, FLM3
..., bit C1 of the fifth octet, sixth octet, seventh octet, and eighth octet of FLM15
C2, C3 and C4 are for displaying a CRC (Cyclic Redundancy Check) code that is referred to for data error detection (that is, channel quality detection) of two consecutive frames (that is, sub-multiframe). , And the bit E of the fourth octet of the odd frames FLM1, FLM3, ..., FM15 is used to indicate that a transmission error has been detected on the receiving side.

The bit rate allocation signal BAS is, as shown in FIG. 18, even-numbered frames FLM0, FLM2,
.., FLM14, 8-bit data representing the capability BAS or BAS command is arranged, and in the subsequent odd numbered frames FLM1, FLM3 ,.
A double error correction code for error correcting the value of the capability BAS or BAS command transmitted in the immediately preceding frame is arranged.

Further, the transmission of the data of the multi-frame MFL is performed in the order of the frame numbers, and the respective frames FLM0 to FLM15 are transmitted in the octet order from the 1st octet to the 80th octet as shown in FIG. The first bit of the octet is sent first.

That is, each of the frames FLM0 to FLM0
In the FLM 15, the first bit of the first octet is transmitted first and the eighth bit of the 80th octet is transmitted last.

FIG. 20 is a T applied as a transmission control procedure executed when an audiovisual terminal such as a video conference communication terminal apparatus transmits data using the B channel.
TC standard JT-H. 242 shows an example of a general procedure of 242. In this case, an example of a transmission procedure for exchanging audio data, general-purpose data, and moving image data between terminals using two B channels is shown.

First, the calling terminal makes a call to the destination terminal and performs a call setup procedure on the D channel to secure one B channel (hereinafter referred to as the first channel) (Phase A). Frame synchronization is performed while exchanging frame data in which PCM voice data (A-law or μ-law, 64 Kbps) is set on one channel (frame mode), and when frame synchronization is established, mutual capability BAS
Data and command BAS data are exchanged (phase B1-1), the transmission mode to be used at that time is determined, and an additional call setup request for securing the second B channel is started (phase B1-2). ).

From the contents of the exchange of the transmission modes at that time, in principle, the common modes are
For example, a BA which selects according to a predetermined priority order (Phase B1-3) and designates a terminal function from the calling terminal so that the called terminal operates the function in the selected operation mode.
The S command is transmitted to set parameters common to the device functions of the calling terminal and the called terminal (phase B2). As a result, in the first channel, for example, audio data (16 Kbp) corresponding to the transmission mode selected at that time is transmitted.
s) data transmission and moving image data (46.4K)
bps) data transmission is performed (phase C).

When the first channel starts data transmission in the frame mode, the call setup procedure is performed on the second B channel (hereinafter referred to as the second channel) on the D channel (phase CA), and the second channel is established. Then, frame data including only the frame synchronization signal FAS and the bit allocation signal BAS is exchanged using the second channel to establish frame synchronization and multi-frame synchronization (phase CB1-11), and then the first channel and the second channel. Synchronization between channels is established (phase CB1-12).

When the synchronization of the two B channels is completed, the BAS command is sent from the calling terminal side to set the transmission mode (phase CB1-2), and the transmission mode is switched to the set contents (phase CB1-3). ), Common parameters are set (phase CB3).

When the initialization of the second channel is completed in this way, after that, the frame data exchanged on the first channel and the frame data exchanged on the second channel are synchronized with each other. Using the B channel, for example, voice data, general data, and
Video data is 58 Kbps and 6.4 Kbps, respectively
And a data rate of 62.4 Kbps is assigned for data transmission (see FIG. 21). Here, the general-purpose data channel exchanges C & I mode (conference control function) data other than voice data, for example, C & I function, telewriting communication function, and bulk transfer function (group 4 facsimile data, etc.) data. Used for.

To end such data transmission, first, the second channel is disconnected. At this time, the first
For voice data transmission on the channel only, the procedure for setting the common mode is performed (Phase CD
1), the mode of the second channel is switched to the mode 0F of the frame mode (phase CD2). At this time, the first channel and the second channel are asynchronous, and the second channel is in a state in which the call is held in the transmission state of only the frame synchronization signal FAS and the bit allocation signal BAS, and the call of the D channel is disconnected. The call for the second channel can be released by the release procedure.

In the first channel, phase CD1
During the phase CD2, the audio data and the moving image data are transmitted at the total transmission rate of 62.4 Kbps in the frame mode. Further, when the operator of one terminal ends the call, the transmission of the moving image data is finished. In order to use all the transmission capacities of the first channel including the transmission capacity of the moving image data for voice transmission, the mode is switched to the mode 0F (phase D2), and then the call disconnection release procedure of the D channel is performed. Is ready to be released.

Thus, the call disconnection release procedure is executed on the D channel for the first channel and the second channel (phase E), and the audiovisual transmission between the two terminals is completed.

As described above, in an audiovisual terminal such as a video conference communication terminal device, one B channel (first channel) is first secured and a frame mode is established, and then audio data and a moving image are transmitted on this first channel. If the second B channel (second channel) can be set at the same time while assigning the data transmission rate and performing the data transmission in the transient mode, the second channel is set by the D channel call setup procedure. Secure. Then, the first channel transmitting in the transient mode and the newly secured second channel are channel-synchronized, and when the channel synchronization is established, the allocation of the transmission rate of the audio data and the moving image data is reset. However, in order to utilize the increased transmission capacity of the B channel, the coding rule (coding method) of audio data and moving image data is changed so that higher quality audio data and moving image data can be exchanged. There is.

Further, when the data transmission is completed, it is necessary to once change the mode in which the transmission path in which both the first channel and the second channel are synchronized is used to the mode in which only the first channel is used. is there. Therefore, first, each encoding rule of audio data and moving image data is set to a method that optimizes the transmission capacity of the first channel of 62.4 Kbps, and the transmission mode of only the first channel is changed, while the second channel is , The state of synchronization with the first channel is stopped, the mode shifts to mode 0F in which user data is in an idle transmission state, and the call is disconnected / released by the call disconnection release procedure of the D channel. The first channel is
From two types of media transmission of audio data and video data,
After changing to mode 0F, which is a transmission mode for only voice data, the call is disconnected / released by the D channel call disconnection release procedure.
release. In addition, the first channel, without switching the mode to two types of media transmission of audio data and video data,
It is also possible to disconnect / release the call after directly changing the mode to the mode 0F. In addition, the billing information obtained in the call disconnection / release procedure is managed for each channel.

Here, in the case of the present embodiment, when the first channel is established, as shown in FIG. 22, the capability BAS is exchanged between the calling side and the called side, and the own terminal is exchanged with the other terminal. Notify the device function of. Then, the calling side sends a BAS command designating a function to be used in the state in which the first channel is being established to the called side based on the capability value exchanged at that time, and the called side receives the designated value. The BAS command for accepting the function is sent to the calling side.

In this case, the exchange of the capability BAS is performed twice. At the first exchange of the capability BAS, the basic device function is notified and the next capability BAS is exchanged, as shown in FIG.
At the time of exchange, as shown in FIG. 24, non-standard functions such as multiplexed video capability are also notified. In the case of the present embodiment, since two video signal input / output systems are provided, the capability values are exchanged with the video signal multiplexing degree being 2.

Then, when the video call communication session is being executed after the setting of the supplementary call, a video setting for determining the image quality of each of the two video sources is attempted for the other terminal. In this case, the BAS command in the signal format as shown in FIG. 25A is sent to the partner terminal.

The video setting information in this BAS command has information elements as shown in FIG. Here, the video-specific frame switching instruction information is for designating whether or not the video 1 processing frame number information and the video 2 processing frame number information are valid, and the video 1 processing frame number information and the video 2 processing frame information. The frame number information is for setting the frame rate (the number of frames) of the video signals of the video source numbers 1 and 2 to the partner terminal.

The video-by-video quantization step number switching information is for designating whether or not the video 1 quantization step number information and the video 2 quantization step number information are valid. The step number information and the video 2 quantization step number information are for setting the number of quantization steps of the video signals of the video source numbers 1 and 2 to the partner terminal.

The video-specific frame mode switching instruction information is for designating whether the video 1 frame mode information and the video 2 frame mode information are valid or not.
As the frame mode information, the frame mode of the video signals of video source numbers 1 and 2 is CIF / Q
It is for setting to CIF.

For example, as shown in FIG. 26A, the screen of the video source # 1 received from the partner terminal is displayed on the video monitor device 13, and the screen of the video source # 2 is displayed on the video monitor device 14. While the user is
As shown in FIG. 7B, a child screen PP having an area of about ¼ of the entire screen is set in the screen of the video monitor device 13, and the screen of the video source # 2 is displayed on this child screen PP. So, let's consider the case where it is specified.

In this case, first, the screen of the video source # 2 displayed on the child screen PP has a smaller display area than the screen of the video source # 1. The image is perceived by the user as an image of a level that does not cause any problem.

Therefore, in this case, the frame mode of the video signal of the video source # 2 is set to 1/4 of the pixel number of CIF.
Can be set to QCIF. Therefore,
In this case, video 1 frame mode switching instruction information in which data for designating that video 1 frame mode information and video 2 frame mode information are set, and video 1 frame in which data for setting frame mode to CIF are set Video 2 with mode information and data that sets the frame mode to QCIF
A BAS command including the video setting information having the frame mode information is formed, and the BAS command is transmitted to the partner terminal.

As a result, the partner terminal sets the frame mode of the video source # 1 to CIF and the frame mode of the video source # 2 to QCIF, and transmits the subsequent moving image signals.

Also, for example, if the user selects the video source #
When the image quality adjustment is operated on the display screens # 1 and # 2, video setting information representing the adjustment content is formed,
Form a BAS command containing the video setting information,
The BAS command is transmitted to the other terminal.

For example, when the user operates the image quality adjustment in the "fine" direction, the video 1 quantization step number information and the video 2 quantization step information are increased in the direction of increasing the quantization step number corresponding to the video source. Set the contents of the numerical information.

As a result, the quantization step value becomes small at the encoding stage of the corresponding video source, and thus a finer image quality can be obtained.

Further, when the user operates the image quality adjustment in the "good trackability" direction, the video 1 processing frame number information and the video 2 processing frame number information are set in the direction of increasing the frame rate corresponding to the video source. Set the contents of.

As a result, the frame rate of the corresponding video source is increased, and a screen with good followability can be obtained.

FIG. 27 shows an example of processing of the system control unit 1 when the screen is operated by the user.

First, whether or not there is a screen operation is monitored (NO loop of decision 401), and if the result of decision 401 is YES due to the screen operation, it is checked whether or not there is an instruction to open a child screen. (Decision 402).

When the result of the judgment 402 is YES, the video monitor device 1 instructed to open the child screen is displayed.
The display control units 16 and 17 corresponding to 3 and 14 are instructed to form a child screen, and the display control units 16 and 17 corresponding to the other video monitor devices 13 and 14
17 is instructed to stop the display (process 4)
03).

Next, the frame mode of the video source designated to be displayed on the child screen is set to QCIF, and the frame mode of the video source designated to be displayed on the parent screen which is the background of the child screen. To C
The above-mentioned video setting information having the contents set in the IF is formed, a BAS command including the video setting information is formed (process 404), the BAS command is transmitted to the partner terminal (process 405), and the determination 401 Return to.

When the content of the screen operation is not the operation of opening the child screen and the result of judgment 402 is NO, it is checked whether or not the content is image quality adjustment (decision 40).
6). When the result of determination 406 is YES, the above-mentioned video setting information is formed corresponding to the contents of the image quality adjustment, and the BAS command including the video setting information is formed (processing 407), and the processing is performed. After proceeding to 405 and transmitting the formed BAS command to the partner terminal,
Return to determination 401.

When the result of the judgment 406 is NO, after the screen operation processing corresponding to the contents of the screen operation designated at that time is executed (processing 408), the judgment 40 is made.
Return to 1.

FIG. 28 shows a processing example of the system control unit 1 when a BAS command is received from the partner terminal.

First, the reception of the BAS command is monitored (NO loop of decision 501). When the BAS command is received and the result of decision 501 is YES, the contents of the BAS command are analyzed (process Fifty
2) It is checked whether the content is video setting information (decision 503).

When the result of judgment 503 is YES, the parameters of the multiplexed video CODEC 15 are set to the designated contents (process 504) and the process returns to judgment 501. When the result of determination 503 is NO, B
The process corresponding to the contents of the AS command is executed (process 5
05), and returns to the determination 501.

By the way, in the above-mentioned embodiment, the present invention has been described in the case of having two video input / output systems. However, the present invention is similarly applied to the case of having three or more video input / output systems. Can be applied.

Further, the present invention can be similarly applied to a moving picture communication terminal device other than the video conference communication terminal device.

[0162]

As described above, according to the present invention,
Multiplexes multiple video signals from multiple video sources
Since it can be exchanged by one transmission means, there is an effect that a video conference communication session applying a plurality of video sources can be realized at low cost and appropriately.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a video conference communication terminal device according to an embodiment of the present invention.

FIG. 2 is a multiplexed moving image CODE according to an embodiment of the present invention.
The block diagram which showed the C apparatus.

FIG. 3 is a schematic diagram showing an example of a signal format of moving image information.

FIG. 4 is a schematic diagram showing another example of a signal format of moving image information.

FIG. 5 is a schematic diagram showing an example of a data format of moving image information.

FIG. 6 is a block diagram showing an example of an information source encoder.

FIG. 7 is a block diagram showing an example of an information source decoder.

FIG. 8 is a schematic diagram showing an example of a timer value table for each video source.

FIG. 9 is a schematic diagram showing an example of video source switching.

FIG. 10 is a flowchart showing an example of a video source switching process.

FIG. 11 is a schematic diagram showing an example of a cumulative frame value table for each video source.

FIG. 12 is a schematic diagram showing another example of video source switching.

FIG. 13 is a flowchart showing another example of the video source switching process.

FIG. 14 is a flowchart showing still another example of the video source switching process.

FIG. 15 is a schematic diagram showing an example of a multi-frame frame configuration.

FIG. 16 is a schematic diagram showing an example of a signal configuration of one frame.

FIG. 17 is a schematic diagram showing an example of a frame adjustment signal.

FIG. 18 is a schematic diagram showing an example of a bit allocation signal.

FIG. 19 is a schematic diagram for explaining a signal transmission order.

FIG. 20: TTC Recommendation JT-H. The time chart which showed the example of the general procedure of 242.

FIG. 21 is a schematic diagram showing an example of allocation of transmission capacities to audio data, general-purpose data, and moving image data in data transmission using two B channels.

FIG. 22 is a time chart showing an example of a procedure for exchanging a capability BAS and setting a transmission mode before setting an additional call.

FIG. 23 is a schematic diagram showing an example of contents of initial capability information exchange.

FIG. 24 is a schematic diagram showing an example of the contents of the next capability information exchange.

FIG. 25 is a schematic diagram showing an example of the contents of a BAS command for video setting.

FIG. 26 is a schematic diagram showing an example of screen switching.

FIG. 27 is a flowchart showing an example of a main part of a process when operating a screen.

FIG. 28 is a flowchart showing an example of a main part of a process performed when a BAS command is received.

[Explanation of symbols]

1 System Control Unit 2 ROM (Read Only Memory) 3 RAM (Random Access Memory) 11, 12 Video Camera Device 13, 14 Video Monitor Device 15 Multiplexed Video CODEC 25 Information Source Encoder 26 Video Signal Multiplexed Code 28 control unit 29 memory 31 video signal multiplex decoder 32 information source decoder SL1, SL2, SL3, SL11, SL12, SL1
3 selector SW1, SW2, SW11 switcher DF subtractor CVa converter QZa quantizer IQZa, IQZb inverse quantizer ICVa inverse converter SMa, SMb adder MPa1 to Mamp, MPb1 to MPbn image memory FLa, FLb loop filter

Claims (5)

[Claims] 1. A video conference communication terminal device having at least a communication function for exchanging audio information and moving picture information, wherein a plurality of moving picture signal output means for outputting a plurality of moving picture signals and output from the plurality of moving picture signal output means. A plurality of moving image signals that have been input, and a multiplex moving image CODEC unit that multiplexes the encoding process corresponding to each moving image signal and the decoding process of the encoded moving image signals, and the above multiplexed moving image CODEC. The video monitor means for displaying the video of the decoded video signal output from the means and the other terminal exchange the video signal multiplexing capability with the other terminal, and according to the exchanged multiplexing capability. , The above-mentioned multiplexed moving image CO during video conference communication operation
A video conference communication terminal device comprising transmission control means for controlling the multiplexing process of the DEC means. 2. The multiplexed moving image CODEC means performs an intra-frame encoding process for encoding all images for one frame and an inter-frame encoding process for forming and encoding a difference between images between frames. A moving picture input means for switching and inputting the plurality of moving picture signals, and a common coding means for coding and compressing a moving picture signal inputted through the moving picture input means. And a decoding means for decoding the code formed by the encoding means, and a plurality of image memory means for storing the decoded moving image signal formed by the decoding means for one frame for each of the plurality of moving image signals. And when performing intra-frame coding processing on each of the plurality of moving picture signals, the moving picture signal input from the moving picture input means is coded and compressed by the coding means to obtain coded information. When forming and performing inter-frame coding processing on each of the plurality of moving picture signals, a decoded moving picture signal corresponding to each moving picture signal read out from the plurality of image memory means and each input from the moving picture input means. While forming a difference between the moving image signals, and encoding and compressing the difference moving image signal by the encoding means to form encoded information, each encoded information identifies each of the plurality of moving image signals. 2. The video conference communication terminal device according to claim 1, further comprising encoding control means for adding identification information to the video conference communication terminal device. 3. The video conference communication terminal device according to claim 2, wherein the encoding control means switches the plurality of moving image signals at predetermined time intervals and in frame units. 4. The video conference communication terminal device according to claim 2, wherein the encoding control means switches the plurality of moving image signals for each predetermined number of frames. 5. The multiplexed moving image CODEC unit is formed by the decoding unit, which performs inverse conversion of the encoding unit to decode the encoded information to form a decoded moving image signal. Encoding processing of each moving image signal based on a plurality of image memory means for storing the decoded moving image signal for one frame for each of a plurality of moving image signals and the identification information added to the encoding information to be decoded. In addition to identifying the mode, when the identification information represents intra-frame encoding processing, the encoding information relating to the moving image signal is decoded by the decoding means, and the decoded moving image signal obtained thereby is output to the decoded moving image. When it is output as a signal and stored in the corresponding plurality of image memory means, and the identification information coding information represents interframe coding processing. The decoding means decodes the coded information relating to the moving picture signal, reads the decoded moving picture signal corresponding to the moving picture signal from the image memory means, and reads the decoded moving picture signal and the decoded moving picture signal. 5. The video conference communication terminal device according to claim 2, 3 or 4, further comprising decoding control means for outputting a result obtained by adding the moving picture signals output from the means as an output decoded moving picture signal. .