JPH0690447A - Monitor device for visual telephone - Google Patents

Abstract

PURPOSE:To provide the monitor device for visual telephone which monitors the same picture as the opposite party. CONSTITUTION:The visual telephone is provided with a picture photographing camera 16 and a display device 17, on which picture data is displayed, and compresses picture data and transmits it together with voice data and reproduced picture data received together with voice to give it to the display device. The monitor device is constituted as follows; transmission picture data from the camera 16 or the like is digitized by an A/D conversion part 362 and digital picture data is compressed by a picture compression part 342 and is transmitted, and received picture data is reproduced by a picture reproducing part 341 and is converted to analog picturedata by a D/A conversion part 361 and is given to the display device 17, and a central processing part 31 switches picture data from the picture compression part 342 to reception picture data to give this data to the picture reproducing part 341 in the case of the monitor mode. Thus, the self-portrait of a user is monitored in the same condition as the picture seen by the opposite party.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a videophone, and more particularly to a monitor device for a videophone capable of monitoring a screen currently being transmitted with the image quality of the same condition as the other party.

[0002]

2. Description of the Related Art With the spread of ISDN (Integrated Services Digital Communication Network), videophones using ISDN have been developed. In addition to a conventional telephone that performs only voice communication, this videophone is also capable of communicating a self-portrait of the caller and images of materials and the like. In such a videophone, a voice input from a handset is encoded and a CCD (Charge coupled device) is used.
) Etc., the image of the speaker taken by a camera is compressed and coded, and both are transmitted from the ISDN line via the ISDN communication control section. On the other hand, since the voice and image from the other party's speaker are also encoded and transmitted, they are decoded and the voice is output from the handset, and the decoded image is output to the display. There is.

By the way, in the above-described videophone, the person who is transmitting the image may want to see how the self-portrait being transmitted is displayed on the display of the communication partner. In this case, some conventional videophones have a monitor mode for displaying a self-portrait on the display of their videophone. In this monitor mode, the image data captured by the television camera is directly given to its own display, so that the image data from the camera is displayed on the display.

[0004]

However, in the above-mentioned conventional videophone, the image displayed on the display of the other party is after the compression encoding by the transmitting side and the decompression decoding by the receiving side. It is an image. on the other hand,
The self-portrait displayed on the self-display in the monitor mode is the self-portrait directly displayed on the image data from the camera without processing such as compression. Therefore, between the self-portrait displayed on its own display in the monitor mode and the image actually viewed by the other party,
There are considerable differences in image quality and image information. Therefore, the image as the sender thinks may not be sent to the other party, and there is a risk that both parties may not be able to perform smooth communication. Therefore, an object of the present invention is to solve the above problems and provide a monitor device for a videophone capable of monitoring an image substantially equivalent to that of the other party.

[0005]

According to the present invention, a camera for photographing an image and a display for displaying the image data are provided, and the image data is compressed and transmitted together with the voice data. In a videophone to be reproduced and given to a display, a transmission image processing means for compressing and transmitting image data to be transmitted, a reception image processing means for reproducing received image data and giving it to a display, and a monitor mode are set. At this time, the monitor device of the videophone is equipped with a central processing means for converting the image data from the transmission image processing means into the reception image data and giving it to the reception image processing means. Here, the transmission image processing means includes an A / D conversion unit that digitizes transmission image data from a television camera or the like, and the A / D conversion unit.
It is sufficient to include at least an image compression unit that compresses the digital image data from the / D conversion unit. Further, the received image processing means may be provided with at least an image reproduction section for reproducing the received image data and a D / A conversion section for converting the image data from the image reproduction section into analog image data.

[0006]

In the monitor device of the videophone, the image data of the self-portrait photographed by the camera is once compressed by the transmission image processing means, stored in the memory of the central processing means, and then the image data read from the memory is centrally processed. The image is displayed on the display by giving the received image processing means from the processing means. In this way, most of the processing until the image data from the camera is displayed on the other party's display is passed, so the monitored image and the image displayed on the other party's display are the same and sent. Discrepancies due to differences in images are eliminated.

[0007]

The present invention will be described below with reference to the illustrated embodiments. A preferred embodiment of a monitor device for a videophone according to the present invention will be described below in detail with reference to FIGS. First, the configuration of the videophone will be described with reference to FIGS. 1 to 3, and then the operation of the videophone will be described with reference to FIGS. 5 and 6. Next, the configuration of an embodiment of the videophone monitor device according to the present invention will be described with reference to FIG.
The operation of the device will be described with reference to FIG.

FIG. 1 shows an external structure of a videophone. As shown in FIG. 1, the videophone 10 includes a base 11, a handset 12 is arranged on the left side of the base 11, and a display support 13 is arranged on the right side.

The handset 12 is for carrying out a telephone call and includes a microphone and a speaker (not shown). A speaker 14 and various operation keys 15 are arranged on the upper surface of the base 11. The operation keys 15 include a speaker volume knob 15 for adjusting the volume of the speaker 14.
1, a handset volume knob 152 for adjusting the volume of the handset 12, various function keys 153 associated with the telephone function,
Numeric keypad 154 for dialing, recording key 155 associated with TV function, privacy key 156, menu screen key 157 for displaying menus such as various mode settings
Various operation keys 15 such as are arranged.

A camera 16 composed of, for example, a CCD is arranged on the front side of the upper portion of the display support 13 so as to photograph the speaker. Further, a display 17 for displaying an image is attached to the side surface of the display support 13 on the handset 12 side. On the display 17, the image of the other party transmitted from the videophone of the other party is displayed and the operation key 1
A menu screen is displayed according to various modes designated by the operation of 5, and the image captured by the camera 16 and transmitted to the other party is displayed after being combined with the image of the other party. Various displays such as displaying predetermined message texts and icons (pictograms) individually or in combination with images are performed.

A VT (not shown) is provided on the rear side surface of the base portion 11.
VTR connection terminals 25a to 25d for connecting R26
Are arranged. VT connected to this connection terminal 25
R26 and camera 16 attached to videophone 10
A camera switch key 18 for switching between and is arranged on the right side surface of the display support 13. Further, on the right side surface of the display support portion 13, a shooting condition switching key 19 for switching shooting conditions such as an aperture according to the brightness of a room shot by the camera 16, a color of an image displayed on the display 17 (RGB ) Color adjustment knob 2 for adjusting
0 and the cap 21 are arranged at predetermined positions. The cap 21 is for covering a screw (not shown) for fixing the display 17 to the display support 13. The display 17 is attached by a biasing force toward the display supporting portion 13 by a spring so as to be vertically rotatable about the center of the cap 21.

FIG. 2 shows a schematic configuration of a circuit of such a videophone. As shown in this FIG.
The videophone includes a central processing unit 31. This central processing unit 31 is a well-known CPU (central
processing unit) 311, a memory 312 including a ROM (read only memory) storing various programs and data for communication and a RAM (random access memory) serving as a working memory storing various data. I have it. In this RAM, for example, a telephone number of a person who can receive an incoming call in an incoming call restriction mode for restricting incoming calls other than the designated caller, which is set by operating the function keys 153 and the numeric keypad 154, a speed dial, and Various data such as various flags indicating states such as standby, outgoing call, incoming call, and communication are stored. The central processing unit 31 also includes a chip set 313 as a communication interface, and a key controller 314 that controls instruction signals input from various keys of the operation keys 15.

The central processing unit 31 is provided with a communication control unit 3 via a bus line (ISA bus) 32 such as a data bus.
3 and the image processing unit 34 are connected. Also,
Via the ISA bus 32, various information processing devices such as a personal computer, CAD (computer aided design), DTP (desk top publishing) can be connected. The communication control unit 33 uses the I
It has an SDN connection terminal 331 and is connected to an ISDN line. This communication control unit 33 uses a communication control signal,
It controls transmission and reception of data such as audio data and image data. The image processing unit 34 performs communication control of the image reproduction unit 341 that reproduces the compressed image data transmitted from the videophone of the other party via the communication control unit 33, and the image data supplied from the camera 16 or the VTR 26. An image compression unit 342 that performs compression processing for transmission by the unit 33 is provided.

The video telephone 10 further includes an image processing unit 34.
D / A (digital / analog) converter 3 connected to
6. Image combining unit 37 connected to the D / A conversion unit 36
Also, an audio control unit 38 connected to the image composition unit and the communication control unit 33 is provided. The audio control unit 38 includes a voice input / output terminal 25 of the handset 12, the speaker 14, and the VTR connection terminal 25.
a, 25c and the chip set 313 are connected. The audio control unit 38 switches between audio switching, hold tone, and DTMF (dual tone multiplex freq).
uency), the volume of the speaker 14 and the handset 12 are adjusted.

The D / A conversion unit 36 converts the image data reproduced by the image reproduction unit 341 of the image processing unit 34 from a digital signal to an analog video signal (NTSC; national tel).
D / A section 36 to convert to an evision system committee)
1 and A / D for converting an analog video signal supplied from the image synthesizing unit 37 into digital image data
A section 362 is provided. The digital image data converted by the A / D unit 362 is the image compression unit 3 of the image processing unit 34.
42.

The image composition section 37 includes an amplifier (AMP) 37.
1, picture-in-picture section 372, AMP3
73 and a changeover switch unit 374, and VT
It is connected to the video input / output terminals 25b and 25d of the R connection terminal 25 and the display 17. AMP371 is
An analog video signal taken by the camera 16 or V
The analog video signal supplied from the VTR 26 via the TR connection terminal 25b is amplified. Both video signals are selected by the camera switching key 18 in FIG.
It is determined by the connection state of the changeover switch unit 374 by the switching operation of. The analog video signal amplified by the AMP 371 is normally supplied to the A / D unit 362, and when the image synthesizing function is designated by the operation key 15, the A / D unit 362 and the picture-in-picture unit 37 are operated.
It is supplied to both of the two.

Picture-in-picture section 372
AMPs the image data supplied from the D / A unit 361.
Supply to 373. Further, when the image synthesizing function is designated to be operated by the operation keys 15, the video signal supplied from the D / A unit 361 (the image signal transmitted from the videophone on the other end of the call) and the AMP 371 are supplied. Video signal (self-portrait or VTR taken by camera 16
The video signal supplied from 26) is synthesized according to the designated state of the operation keys 15, and the synthesized video signal is AMP.
Supply to 373. AMP373 is supplied NTSC
The signal is amplified and supplied to the display 17. The display 17 displays the supplied video signal in color.

FIG. 3 shows a circuit configuration in the image processing section 34. As shown in FIG. 3, the image processing unit 3
The image reproducing unit 341 of No. 4 stores a first-in first-out FIFO memory 341a in which the image data supplied from the ISA bus 32 is stored, a Huffman decoding unit 341b that performs Huffman decoding of the image data in the FIFO memory 341a, and an image after decoding. Block memory 341 in which data is stored
c, a compression playback unit 341d that reads out image data stored in the block memory 341c and plays back image data compressed by motion compensation interframe prediction, DCT, or the like.

The block memory 341c has an area for two frames, alternately stores Huffman-decoded image data, and the area other than the area in which this image data is stored (the area of the previous frame). The image data is read out from the area where the image data is stored) and is compressed and reproduced. Then, when the recording key 155 (FIG. 1) is pressed, the compressed image data before reproduction stored in the block memory 341c is supplied to the central processing unit 31 via the ISA bus 32 and stored in the memory 312. RAM
It is designed to be stored in.

On the other hand, the image compression section 342 has a setting parameter storage section 342a in which parameters for setting image quality are stored, a block memory 342b in which digital image data supplied from the D / A conversion section 36 is stored, A compression unit 342c that compresses the image data stored in the block memory 342b by motion compensation inter-frame prediction, DCT, etc., a Huffman coding unit 342d that further Huffman-codes the compressed image data, and a buffer memory 3
42e. Setting parameter storage unit 342a
Is connected to the CPU 311 via the ISA bus 32, and when the caller specifies the image quality, each parameter specified by the caller or the other party's speaker is stored.
Further, it is set and changed automatically by an instruction from the CPU 311.

FIG. 4 is a block diagram shown for explaining an embodiment of a monitor device for a videophone according to the present invention. The videophone monitor device of this embodiment is configured as shown in FIG. 4 by pressing the monitor key of the operation keys 15.
Now, the configuration of the monitor device for the videophone shown in FIG. 4 will be described below. The output of the television camera 16 is output to the A
It is connected to the input terminal of the MP 371 so that the image data from the camera 16 can be supplied to the AMP 371. The output of the AMP 371 is the D / A conversion unit 36.
Connected to the input terminal of the A / D converter 362 of
The image data amplified by the MP371 is converted into an A / D conversion unit 362.
Can be supplied to. The output of the A / D conversion unit 362 is connected to the image compression unit 342 of the image processing unit 34 so that the digital image data digitally converted by the A / D conversion unit 362 can be supplied to the image compression unit 342. Has become. The image compression unit 342 of the image processing unit 34 is connected to the central processing unit 31 and the communication control unit 33 via an ISA bus (not shown), and the image data compressed by the image compression unit 342 is transferred to the central processing unit 31. CPU 311
Under the control of (1), the data can be temporarily stored in the RAM of the memory 312 and can also be supplied to the communication control unit 33.
Further, the AMP 371, the A / D conversion unit 362, and the image compression unit 342 constitute a transmission image processing unit. Further, the central processing unit 31 is connected to the image reproducing unit 341 of the image processing unit 34 via an ISA bus (not shown), and can supply the image data temporarily stored in the memory 312. The image reproduction section 341 is connected to the D / A conversion section 361 and supplies the image data obtained by image reproduction to the D / A conversion section 361. D
The output of the A / A converter 361 is connected to the picture-in-picture unit 372 of the image synthesizer 37. The output of the picture-in-picture unit 372 is AMP3.
After being amplified at 73, it can be supplied to the display 17. Image reproduction unit 341, D / A conversion unit 36
1, picture-in-picture section 372, and A
The MP373 constitutes a received image processing means.

Next, the operation of the videophone thus constructed will be described. First, the normal operation of the videophone will be described. (1) Operation of Main Routine First, the main operation of the main routine will be described. In the main routine, the CPU 311 detects each state FG (flag) of the memory 312 and performs each process, and in the process, changes the predetermined state FG to shift to the next process or the previous process. . That is, normally, the waiting process is repeated to monitor the outgoing call or incoming call, and when the outgoing call or incoming call is detected, a predetermined F
After changing G, the process shifts to the corresponding process. In the outgoing call and incoming call processing, when normal processing is performed, the processing shifts to in-communication processing. Then, when the in-communication process ends, or when a specific operation or the like is performed in the incoming or outgoing call process, the process returns to the waiting process and the outgoing or incoming call is monitored again.

Next, details of the main routine are shown in FIG.
Follow the instructions below. When installing the videophone 10, etc.
Initialization of the SDN board (communication control unit 33), image processing board (image processing unit 34), keyboard (operation keys 15), and image composition board (picture-in-picture unit 372) and initialization of various memory areas Settings are made (step 10). Then, when the operator of the videophone processes the operation keys such as the function key 153 and the numeric keypad 154 (step 11), the CPU 311 causes the D
Transfer to I / O processing and accept output of control signal to each board and supply of status signal from each board (step 1
2).

Then, the CPU 311 accesses the flag storage area of the RAM 312 in the memory 312, confirms whether any of the flags is in the ON state, executes the process corresponding to the flag in the ON state, and goes to a predetermined portion. The instruction signal of is output. That is, the CPU 311 shifts to the waiting process (step 14) when the waiting FG is ON (step 13; Y), and shifts to the calling process when the calling FG is ON (step 15; Y). (Step 16) When the FG during the incoming call is ON (Step 17; Y)
To the in-communication process (step 18), and when the in-communication FG is ON (step 19; Y), the in-communication process is performed (step 20). Then, when all the flags are OFF, and after any of the processes from step 14 to step 20 is completed, the process returns to step 11 to continue the process.

(2) Processing during communication FIG. 6 shows the operation of the processing during communication on the transmission side. In this in-communication process, the in-communication FG is changed to the ON state in the outgoing call process of FIG. 5 (step 16), or the in-communication FG is changed to the ON state in the incoming call process of FIG. 5 (step 18). The process is thereby started. First, the CPU 311 monitors whether or not the calling party has issued a communication disconnection request to the communication control unit 33 via the ISDN line (step 201). If there is no disconnection request (step 201; N), the handset 12 is on-hook (step 202; Y), and if the hold key or the speaker key is pressed in advance (step 203; Y), hold, send pause. Etc., perform effective functional processing even during a call (step 20).
4).

That is, as each functional process, a holding process, a transmission pause process, a privacy process, a recording process, a menu process, an image process and the like can be mentioned. Since the image processing corresponds to the embodiment of the present invention, it will be described in detail later, but the outline will be described here. That is, when the self-portrait processing is selected, each element shown in FIG. 2 is processed by the configuration as shown in FIG. That is, on the display 17, not the image data transmitted from the other party's videophone but the self-portrait imaged by the camera 16 or the VTR 26 is displayed.
To display. While looking at the self-portrait displayed on the display 17, the caller sets or changes the screen size or the image quality mode and confirms in what state the self-portrait is transmitted to the other party. This image quality mode includes a designated image quality mode in which image data is transmitted at a designated constant image quality, and an automatic image quality mode in which the movement of the image data is monitored and an appropriate image quality of the self image according to the movement is selected.

On the other hand, when the partner image processing is selected, the partner image processing screen is displayed on a part of the display 17 on which the partner image is displayed. The caller specifies the screen size of the partner image and the image quality mode of the partner image according to the instruction on the partner image processing screen while looking at the partner image displayed on the display 17. When the image quality mode of the partner image is designated, the CPU 311 transmits a corresponding control signal from the communication control unit 33 to the partner videophone. Upon receiving this control signal, the other party's videophone changes to the designated image quality.

After the respective functional processings described above are completed, the image communication processing is performed (FIG. 6, step 20).
5). That is, when the ISDN board (communication control unit 33) is in the data transmission OK state, the image control unit 3 captures the image data, attaches a communication header to each transmission block, and adds the communication header
Send from 3. If there is received data in the communication control unit 33, it is received, and the image data is displayed on the display 17 via the image processing unit 34, the D / A conversion unit 36, and the image synthesizing unit 37 for each frame of image data. . The received voice data is output to the handset 12, the speaker 14, or the VTR connection terminal 25a via the audio control unit 38.

In step 202, when the handset 12 is in the off-hook state (step 202;
N), it is determined whether or not a predetermined key input is made from the operation keys 15 (step 206). If a key input has been made (step 206; Y), the process proceeds to each functional process of step 204, and if no key input has been made (step 20).
In 6; N), the process proceeds to the image communication process of step 205.

On the other hand, in step 201, when the other party issues a disconnection request (step 201; Y) and it is normally terminated (step 207; Y), or in step 203, both the hold key and the speaker key are pressed. If it has not been pressed in advance (step 203; N), C
The PU 311 performs communication end processing (step 20).
8). That is, as the communication end processing, the handset 1
The videophone on the side where 2 is on-hook sends a disconnection message to the voice line, and sends a disconnection message to the data line when release is returned. On the other hand, the videophone on the disconnected side sends out the data disconnection message when receiving the audio disconnection message. Here, the display 17 on the calling side displays the charge and the call time, and the display 17 on the receiving side displays only the call time.

Thereafter, the CPU 311 turns the communicating FG in the ON state into the OFF state and changes the waiting FG in the OFF state into the ON state (step 209), and thereafter, by the return processing, the waiting processing in FIG. Go to (Step 14). At step 207, as in the case where an error occurs in the image data line, if the process is not completed normally (step 207; N), communication error processing is performed (step 210). That is, as the communication error processing, the line of the image data is disconnected and only the voice communication is performed.
In this case, the display 17 displays only a predetermined image stored in the RAM in advance and a message indicating that there is a communication error.

Next, the transmission / reception operation of image data during the communication processing will be described with reference to FIGS. 2 and 3. Self-portrait taken by camera 16 or VTR2
The video signal of the video supplied from 6 is amplified by the AMP 371 and then supplied to the D / A conversion unit 36. Here, the analog video signal is converted into digital image data by the A / D unit 362 and then supplied to the image processing unit 34.

The image data supplied to the image processing section 34 is stored in the block memory 342b as original image data. The compression unit 342c takes in predetermined data from the original image data stored in the block memory 342b according to the parameters stored in the setting parameter storage unit 342a. Then, the motion-compensated inter-frame prediction, image compression by DCT, etc. is performed on the captured image data. The compressed image data is further Huffman encoded and sequentially stored in the buffer memory 342e. The image data stored in this buffer memory 342e is
Taken into the central processing unit 31 via the ISA bus 32,
Further, via the ISA bus 32, the ISD is transmitted from the communication control unit 33.
Sent to N lines. The transmitted image data is reproduced on the videophone of the other party and displayed on the display 17.

On the other hand, the image data from the other party's videophone received by the communication control unit 33 is supplied to the central processing unit 31 via the ISA bus 32. Since this image data has been compressed by the other party's videophone, it is sequentially supplied to the image reproducing unit 341 for reproduction by a method opposite to that compressed by the image compressing unit 342. Image reproduction unit 341
Image data supplied to the FIFO memory 341 sequentially.
After being stored in a, decoded by the Huffman decoding unit 341b, stored in the block memory 341c in frame units. The data stored in the block memory 341c is reproduced by the IDTC or the like in the compression reproduction unit 341d and supplied to the D / A conversion unit 36. The image data before compression reproduction stored in the block memory 341c is supplied to the central processing unit 31 via the ISA bus 32 when the recording key 155 is pressed, and the memory 312 is stored.
Is stored and saved in the RAM.

The digital image data supplied to the D / A conversion unit 36 is converted into an analog video signal by the D / A unit 361, and the picture-in-picture unit 372.
Then, if necessary, it is combined with the video signal of the self-portrait supplied from the camera 16 or the like, supplied to the display 17 via the AMP 373, and displayed.

Next, the operation of the monitor device of the videophone will be described with reference to FIGS. 1 to 4 and 7. In the videophone, each function process (step 20 in FIG. 6)
4) or image communication processing (step 205 in FIG. 6)
When a predetermined function key among the operation keys 15 is pressed during the process of (step 301; Y in FIG. 7), the monitor mode is set and the respective components are connected as shown in FIG. 4 (step 302). . Then, the monitor device of the videophone connected in this manner performs the following monitor mode processing (step 303). If the operation key 15 is not pressed (step 301; N), the monitor mode is not processed and the process shifts to another process. That is,
The video signal of the self-portrait photographed by the camera 16 or the video supplied from the VTR 26 is selected by the changeover switch 374, amplified by the AMP 371, and then supplied to the D / A conversion unit 36. Here, the analog video signal is A
After being converted into digital image data by the / D unit 362, it is supplied to the image processing unit 34.

The image data supplied to the image processing unit 34 is stored in the block memory 342b as original image data. The compression unit 342c takes in predetermined data from the original image data stored in the block memory 342b according to the parameters stored in the setting parameter storage unit 342a. Then, the motion-compensated inter-frame prediction, image compression by DCT, etc. is performed on the captured image data. The compressed image data is further Huffman encoded and sequentially stored in the buffer memory 342e. The image data stored in this buffer memory 342e is
Taken into the central processing unit 31 via the ISA bus 32,
Further, via the ISA bus 32, the ISD is transmitted from the communication control unit 33.
Sent to N lines. The transmitted image data is reproduced on the videophone of the other party and displayed on the display 17.

On the other hand, the image data stored in the buffer memory 342e is stored in the central processing unit 3 via the ISA bus.
1 is supplied. Since this image data has been compressed, it is sequentially supplied to the image reproducing unit 341 to be reproduced by a method opposite to that compressed by the image compressing unit 342. The image data supplied to the image reproducing unit 341 is sequentially stored in the FIFO memory 341a, decoded by the Huffman decoding unit 341b, and then stored in the block memory 341c in units of frames. This block memory 341
The data stored in c is reproduced by the IDTC or the like in the compression reproduction unit 341d and supplied to the D / A conversion unit 36. The image data before compression reproduction stored in the block memory 341c is supplied to the central processing unit 31 via the ISA bus 32 when the recording key 155 is pressed, and stored in the RAM of the memory 312. Saved.

The digital image data supplied to the D / A conversion unit 36 is converted into an analog video signal by the D / A unit 361, and the picture-in-picture unit 372,
It is supplied to the display 17 via the AMP 373.
As a result, the image captured by the camera 16 is displayed on the display 17.

As described above, in the present embodiment, the image from the camera 16 is not directly displayed, but the image compressed by the image compressing unit 342 and decoded by the image reproducing unit 341 is displayed on the display 17, so that it is almost the same. Since the process up to the display by the other party is passed, it is possible to see the same image as the image the other party is seeing. Therefore,
When the image of the sending side and the image of the other party are almost the same and the image is difficult to understand, the image quality can be adjusted appropriately, and smooth conversation can be carried out by both sides.

[0040]

As described above, according to the present invention, when the monitor mode is set, the image data from the camera is not directly displayed but the image data from the transmission image processing means is converted into the reception image data. Instead, since it is given to the received image processing means, it is possible to see an image almost the same as the image seen by the other party. Further, in the case of an image that is difficult to understand, the image quality can be adjusted appropriately, and both parties can have a smooth conversation.

[Brief description of drawings]

FIG. 1 is an external configuration diagram of a videophone to which an embodiment of the present invention is applied.

FIG. 2 is a circuit configuration diagram of the videophone.

FIG. 3 is a block diagram showing details of the image processing unit.

FIG. 4 is a block diagram showing an embodiment of the present invention.

FIG. 5 is a flowchart showing an operation of a main routine of the videophone.

FIG. 6 is a flowchart showing an operation of a process during communication of a videophone.

FIG. 7 is a flowchart of the operation of the videophone monitor device of the present invention.

[Explanation of symbols]

 10 Video Phone 11 Base Part 12 Handset 13 Display Support 14 Speaker 15 Operation Key 16 Camera 17 Display 18 Camera Change Key 19 Shooting Condition Change Key 20 Color Adjustment Knob 21 Cap 25 VTR Connection Terminal 31 Central Processing Unit 311 CPU 312 Memory 32 ISA bus 33 Communication control unit 34 Image processing unit 341 Image reproduction unit 341a FIFO memory 341b Huffman decoding unit 341c Block memory 341d Compression reproduction unit 342 Image compression unit 342a Setting parameter storage unit 342b Block memory 342c Compression unit 342d Huffman encoding unit 342e Buffer memory 36 D / A converter 37 Image synthesizer 38 Audio controller

Claims (1)

[Claims] 1. An image to be transmitted in a videophone having a camera for photographing an image and a display for displaying the image data, transmitting the image data together with the sound data, and displaying the image data received together with the sound on the display. Transmitting image processing means for compressing and transmitting data, receiving image processing means for reproducing the received image data and giving it to the display, and receiving image data from the transmitting image processing means when the monitor mode is set. A monitor device for a videophone, comprising: a central processing means for supplying the received image processing means in place of the image data.