JPH09121333A - Image transmitter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To freely switch images to be received in the reception side, and to simultaneously display two kinds of received images in an image transmitter capable of transmitting/receiving a moving image and a still image. SOLUTION: This device is provided with a still image transmitting processing part 105, a moving image transmitting processing part 107, a changeover switch 109 for data to be transmitted, a changeover switch 113 for data to be received, a still image receiving processing part 115, a moving image receiving processing part 117 and an image composing part 119. In accordance with the instruction of the reception side, the moving image is received while transmitting the still image, or the still image is received while transmitting the moving image. Also, the received still image and moving image are composed and simultaneously displayed by the image composing part 119.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image transmission device for transmitting an image signal using a communication line such as a telephone line, and more particularly to an image transmission device capable of transmitting still images and moving images.

[0002]

2. Description of the Related Art A videophone has been proposed as a typical image transmission device. A videophone is a method of making a call while looking at an image sent from the other party, and the image sent from the other party can be displayed on one's own display monitor. Furthermore, in order to confirm how oneself is reflected, in many cases, not only the image of the other party but also one's own image can be displayed on the monitor at the same time. Such a videophone is described in detail, for example, in Japanese Patent Laid-Open No. 59-158182.

[0003]

Generally, when a moving image is transmitted using a line with a small communication capacity such as an analog public telephone line or an ISDN line of about 64 kbps, transmission is performed in 1 second. Since it is necessary to reduce the number of frames to be played and the resolution of the image to be coarse, it is still impossible to send a moving image with sufficient image quality. As one method of compensating for this, there is a method having a function of transmitting a high-definition still image. However, the above conventional technique is
The present invention was considered for a video phone that can only transmit moving images, and little consideration has been given to a video phone that can also transmit still images.

Therefore, an object of the present invention is to realize a convenient display method and transmission method for a videophone capable of transmitting not only moving images but also still images. Note that the still image according to the present description is an image that takes approximately 1 second or more to transmit one image, and the moving image is an image that can transmit a plurality of images in approximately 1 second.

[0005]

In order to achieve the above-mentioned object, an image transmission apparatus according to the present invention is a still image transmission processing means for performing compression coding processing and the like using an input image as a still image, and an input image as a moving image. Moving image transmission processing means for performing compression encoding processing as an image, transmission switching means for switching image data to be transmitted, still image reception processing means for performing decoding processing on received image data as a still image, and received image Video receiving processing means for performing decoding processing of data as a moving picture, reception switching means for switching processing of received data, combining processing means for simultaneously displaying received still image and moving image, and mode for receiving image are selected. And an operating means for performing the operation.

The operating means selects whether the mode of the image to be received is a moving picture or a still picture, and when a moving picture is selected, the reception switching means is switched to the moving picture reception processing means side for reception. The decoded image data is converted into a moving image and subjected to a decoding process. When a still image is selected as the received image, the reception switching means is switched to the still image reception processing means side, and the received image data is subjected to decoding processing as a still image. Also, according to instructions from the other party,
When the transmission image is a still image, the transmission switching unit is switched to the still image transmission processing unit side, and the image data to be transmitted is compression-encoded as a still image and transmitted. Further, when the transmitted image is a moving image, the transmission switching unit is switched to the moving image transmission processing unit side, and the image data to be transmitted is compressed and encoded as a moving image and transmitted. Also,
The received still image and moving image are combined into one screen by the combining processing means and can be displayed and viewed at the same time.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Each embodiment of the present invention will be described below. FIG. 1 is a block diagram showing an outline of an image transmission system constructed by two image transmission devices according to a first embodiment example of the present invention (hereinafter referred to as the first embodiment example). Note that the audio processing system is omitted in FIG.

In FIG. 1, 101 is an image transmission apparatus (A) according to the first embodiment, 102 is an image transmission apparatus (B) according to the first embodiment, 103 and 104 are video cameras, 1
Reference numerals 05 and 106 denote still image transmission processing units that compress and encode an image captured by a video camera as a still image and perform transmission processing. Reference numerals 107 and 108 compress and encode an image captured by a video camera as a moving image and perform transmission processing. A moving image transmission processing unit, 109 and 110 are transmission changeover switches for switching an image to be transmitted between a still image and a moving image, and 111 and 112 are communication lines for transmission. Here, in order to show the concept of full-duplex communication, they are unidirectional. Although it is drawn as two lines for communication, a two-line telephone line may actually be used.
Reference numerals 113 and 114 denote reception changeover switches for switching whether the received image data is processed as still image data or moving image data, and 115 and 116 are still image reception processing units for decoding the received image data as still image data. Reference numerals 117 and 118 denote a moving image reception processing unit that decodes the received image data as moving image data. Reference numerals 119 and 120 denote image signals for combining the received still images and moving images into a predetermined format and displaying them on a monitor. The combining unit 121 and 122 are monitors for displaying the combined image. Here, as a still image encoding / decoding method, a so-called ADPCM method or ITU-T standard JP is used.
The EG method or the like is used. Further, as a moving picture coding / decoding method, the MPEG method or the H.264 standard is used. The H.261 system or the like is used. Note that reference numerals 123 and 124 denote operation units for operating the entire apparatus, including buttons for setting a received image as a still image or a moving image, and the like.

The outline of the operation will be described. When sending and receiving only moving images to each other like a conventional videophone,
When all the switches 109, 110, 113 and 114 are connected to the b side and only the still images are transmitted and received to and from each other, the switches 109, 110, 113 and 114 are all connected to the a side. Further, in the first embodiment example, the switch 1
09 and 114 are connected to the side a, and switches 110 and 113 are connected to the side b, respectively.
A still image can be transmitted from 101 to the image transmission apparatus (B) 102, and a moving image can be transmitted from the image transmission apparatus (B) 102 to the image transmission apparatus (A) 101. On the contrary, the switches 109 and 114 are set to the b side, and the switch 110 is
And 113 are connected to the side a, respectively, to transmit a moving image from the image transmission apparatus (A) 101 to the image transmission apparatus (B) 102, and from the image transmission apparatus (B) 102 to the image transmission apparatus (A). A still image can be sent to 101.

In the first embodiment, the type of image to be received can be determined by the operation on the receiving side by the operation units 123 and 124. That is, for the image sent from the image transmission apparatus (A) 101 to the image transmission apparatus (B) 102, the image transmission apparatus (B) 1 on the receiving side.
02 by the operation unit 124, and the image transmission apparatus (B) 10
The image transmitted from the image transmission device (A) 101 to the image transmission device (A) 101 from the operation unit 1 of the image transmission device (A) 101 on the receiving side
It can be set at 23. Then, the set image type is sent to the image sending side by a communication control unit (not shown), and each switch is switched.

Next, with reference to FIGS.
An example of the combined image in steps 120 and 120 will be described. FIG. 2 shows an example in which a moving image is displayed on a part of a still image. In the figure, 201 is a received still image, 202 is a received moving image, and 203 is a transmission image taken by a video camera (in the case of a videophone, (Self-portrait), 204 is a still image obtained by freezing the received moving image. FIG. 2A is an example in which the received moving image 202 is embedded in a part of the received still image 201 and displayed. 2 (2) is an image in which the image (usually the self-portrait) to be further transmitted in FIG. 2 (1) is set in a part of the received still image 201. Also,
In (3) of FIG. 2, when moving images are being transmitted to each other, the received moving image 202 is displayed by being embedded in a part of a still image 204 obtained by freezing one screen of the moving image. Here is an example. Although not particularly shown in FIG.
Of course, the transmission image may be displayed at the same time in (3).

FIG. 3 shows an example in which the screen is divided and displayed. In the figure, 301 is a received still image, 302 is a received moving image, 303 is a transmission image photographed and transmitted by a video camera, and 304 and 305. Is the two still images received. (1) of FIG. 3 is not a part of the received still image 301, but the received still image 301 and the received moving image 30.
This is an example in which 2 are simultaneously displayed on one screen. 3 (2) is an example in which the image 303 to be further transmitted is simultaneously displayed in FIG. 3 (1). FIG. 3C shows two received still images 304 and 305 and the received moving image 302.
And four images of the transmission image 303 are simultaneously displayed. In addition, in (1) to (3) of FIG.
The images up to 305 are shown in the same size, but of course, the size may be changed depending on the image. 3 (4) is an example of the case where the received still image 301 is enlarged and the received moving image 302 is reduced in FIG. 3 (1).

FIG. 4 shows another example of a composite display, which is an example in which a horizontally long screen having an aspect ratio of 9:16 is used as a monitor for display. In the figure, 401 is a received still image, 402 is a received moving image, 403 is a transmitted image, and 404 is a frozen still image of the received moving image. FIG. 4A shows an example in which a received still image 401 is displayed large on a part of the screen with an aspect ratio of about 3: 4, and at the same time, a received moving image 402 is displayed small with an aspect ratio of about 3: 4. Is. (2) of FIG. 4 corresponds to (1) of FIG.
Further, it is an example in which the transmission image 403 is displayed in a small size with an aspect ratio of about 3: 4. Further, (3) of FIG. 4 is (2) of FIG.
Furthermore, this is an example in which a still image obtained by freezing one screen of the received moving image is displayed small with an aspect ratio of about 3: 4.

2 to 4, the position and size of each image are not limited to this. For example, in (1) of FIG. 2, the position of the received moving image 202 may be at the upper right, or the size. It goes without saying that can be smaller.

Next, FIG. 5 shows an image transmitting apparatus according to a second embodiment of the present invention, in which the present invention is applied to an image transmitting apparatus for an analog public telephone line.

In FIG. 5, reference numeral 501 is a communication line such as a telephone line, 502 is a network control unit (NCU) for controlling the connection between the line and a modem, and 503 is a digital signal which is modulated into an analog signal or a reverse signal. A communication control unit 504 for controlling the entire communication, 505 a camera, 506 an A / D converter for A / D converting an image signal from the camera 505, and 507 an A / D converter 506. A memory for temporarily storing the image data converted in step 508, a moving image encoder 508 for encoding a moving image,
Reference numeral 09 denotes a still image encoding unit that encodes a still image.
0 is a moving picture decoding unit that decodes the received moving image data,
511 is a still image decoding unit that decodes the received still image data, 512 is a moving image memory for displaying the decoded moving image data, and 513 is a still image for displaying the decoded still image data. A memory 514 is an image synthesizing unit that synthesizes the decoded moving image or still image and the transmission image captured from the camera 505 into a predetermined size and position.
Reference numeral 15 is a D / A converter for D / A converting the combined image data into an analog image signal, 516 is a monitor display for displaying an image, and 517 is setting various modes and functions of the image transmitting apparatus. It is an operation unit for doing. It should be noted that a voice processing system for use as a videophone and a telephone function unit such as dialing are omitted.

Next, the operation will be described. A video signal of a video image captured by the camera 505 is decomposed into a luminance signal and a color difference signal by an A / D converter 506, and then A and D, respectively.
/ D converted and stored in the memory 507 for each screen. When transmitting a still image, the still image encoding unit 509 compresses and encodes the image data stored in the memory 507 according to the JPEG method or the like. When transmitting a moving image, the image data stored in the memory 507 is used as the moving image encoding unit 50.
H.8. It is compression-encoded according to the H.261 system or the like. The compression-encoded image data is packetized by the communication control unit 504 together with various control data, and the modem 50
3 and the NCU 502, and is transmitted to the communication line 501.

The signal sent through the communication line 501 is received via the NCU 502 and the modem 503, and is decomposed into control data and image data by the communication control unit 504. If the image data is still image data, To the still picture decoding unit 511, in the case of moving picture data, the moving picture decoding unit 51
0 to be decoded respectively. Then, the decoded still image data is stored in the still image memory 513,
The decrypted moving image data is stored in the moving image memory 512. The image data stored in the still image memory 513 or the moving image memory 512 is combined by the combining unit 514 in accordance with the display format as shown in FIGS.
The combined image data is converted into, for example, an NTSC standard analog video signal by the D / A converter 515 and displayed on the monitor 516.

The operation unit 517 can instruct the start of communication, operate the display format of the monitor 516, and the like. Control information for making a received image a still image or a moving image can be obtained by the communication control unit 504. It is added as control data to the image data to be transmitted and transmitted. Synthesis part 5
As a concrete synthesizing method in 14, the data to be A / D converted may be switched according to the display format, or an image memory for display may be provided in the synthesizing unit 514, and the image memory may be stored in the image memory according to the display format. The data may be transferred, and this may be A / D converted and displayed.

Next, FIG. 6 shows an image transmission device according to a third embodiment of the present invention, in which the present invention is applied to an image transmission device for analog public telephone lines. The third example of the form shows an example in which the coding and decoding of a still image and the coding and decoding of a moving image are each performed in one block. Also in FIG. 6, a voice processing system for use as a videophone and a telephone function unit such as dialing are omitted.

In FIG. 6, reference numeral 601 is a communication line such as a telephone line, 602 is a network control unit (NCU: Network Control Unit) for controlling the connection between the line and a modem, and 603 is a digital signal modulated into an analog signal or vice versa. 604 is a communication control unit for controlling the entire communication, 605 is a camera, 606 is an A / D converter for A / D converting an image signal from the camera 605, and 607 is a moving image encoding and A moving image codec for decoding, 608 a moving image memory used when encoding and decoding moving images, 609, a still image codec for encoding and decoding still images, and 610, still image encoding Still image memory used when performing decoding or decoding, 611 is a synthesizing unit for synthesizing images to be displayed in a predetermined format, and 612 is storage of synthesized display data. A display memory, 613 is a D / A converter for converting display data into an analog video signal, 614 is a monitor display for displaying an image, and 615 is an operation for setting various modes and functions of the image transmission device. It is a department.

The operation according to the third embodiment is basically as shown in FIG.
Since the second embodiment is similar to the second embodiment, the description thereof will be omitted.

Next, FIG. 7 shows an image transmission apparatus according to a fourth embodiment of the present invention in which the present invention is applied to a videophone compatible with an analog public telephone line.

In FIG. 7, reference numeral 701 is a communication line such as a telephone line, 702 is a network control unit (NCU) for controlling the connection between the line and a modem or a telephone, and 703.
Is a modem for modulating digital data into an analog signal and vice versa, 704 is a telephone section including a handset, dial buttons, etc., and 705 is A / D conversion or D / A conversion of a voice signal. The converter is a so-called μ-law (or A-law) codec, 70
An audio codec 6 performs compression encoding and decoding of audio data, for example, ADPCM system or CELP system. Reference numeral 707 is a video camera that captures an image to be transmitted, 708 is a video decoder that decodes an NTSC standard video signal into a luminance signal and a color difference signal, and further performs A / D conversion, and 709 is a still image encoding / decoding and moving image. An image codec for encoding and decoding an image, which is configured by a dedicated LSI or DSP (Digital Signal Processor). 710 is an image memory for the image codec, 71
1 is D / A converted to the decoded luminance and color difference signals, and N
A video encoder that encodes a video signal of the TSC standard or the like, 712 is a monitor that displays an image, and 713 is an arithmetic processing unit (CPU) that controls the entire apparatus, and is configured by a microprocessor or the like. 714 is a read only memory (RO) for storing control software of the CPU 713.
M), 715 is a random access memory (RAM) used as a work area necessary for the operation of the CPU 713 and a buffer at the time of transmitting and receiving data, 716 is a system bus including an address bus and a data bus, and 717 is an operation of the device. It is an operation unit for performing various operations such as various buttons and switches, and in some cases, a small liquid crystal display.

The basic operation of the fourth embodiment is similar to that of the second embodiment of FIG. 5, etc., but in the fourth embodiment, the entire device is controlled by the CPU 713.

First, when the handset of the telephone unit 704 is taken, the line 701 is connected to the telephone unit 704 via the NCU 702. If you dial the other party's number and the other party answers, you can make a normal call. When the communication start button of the operation unit 717 is pressed in this state, the communication line 701 is disconnected from the telephone unit 704 by the NCU 702 and connected to the modem 703 under the control of the CPU 713. By this operation, the modem 703 is connected to the modem of the other party through the communication line 701, and after a predetermined operation, digital communication is started.

The call voice of the telephone unit 704 is A / D and D.
After being converted into a digital signal by the A / A converter 705, it is compression-encoded by the audio codec 706, and is sent to the other party via the modem 703 together with other control data and image data under the control of the CPU 713. The data received via the modem 703 is sent to the audio codec 706 by the CPU 713 as audio data, and is decoded.
The analog signal is converted back into an analog signal by the / D and D / A converter 705 and can be heard by the handset of the telephone section 704.

On the other hand, the image taken by the camera 707 is
Decoded and A / D converted by the video decoder 708,
It is sent to the image codec 709. Image codec 70
In 9, the image data is compression-encoded according to a preset mode (still image or moving image). The encoded image data is transmitted to the other party via the modem 703 together with other control data and voice data under the control of the CPU 713. Of the data received by the modem 703, the image data is sent to the image codec 709 to be decoded in accordance with a predetermined mode, and the image is combined in the display format as shown in FIGS. The combined image data is converted into a predetermined video signal by the video encoder 711 and displayed on the monitor 712.

In this way, it is possible to talk with the other party's videophone while viewing the image. Further, for example, when switching to a still image while exchanging moving images, if the still image mode is selected by operating the operation unit 717 on the receiving side, the information is transmitted via the modem 703 together with the voice data and the image data. Sent to the other party. Upon receiving this information, the other party switches the encoding process in the image codec 709 from the moving image mode to the still image mode and transmits the image data. In this way, the image to be received can be switched according to the instruction from the receiving side.

FIG. 8 is a diagram showing an example of a part of the operation unit (517 in FIG. 5, 615 in FIG. 6, 717 in FIG. 7) for selecting a received image. In FIG. Parts 802 to 804 are operation buttons. FIG. 8 (1)
In the example shown in, by pressing the operation button 802,
The received image can be made into a moving image or a still image. In the example shown in (2) of FIG. 8, when the operation button 803 is pressed, the received image becomes a moving image, and the operation button 80
By pressing 4, the received image becomes a still image.

FIG. 9 shows an example of the structure of a data packet for transmitting information of the reception mode selected by the receiving side (mode of whether the received image is a moving image or a still image) to the transmitting side. . In the image transmission device like the present invention, the HDL
In many cases, packet communication using flag synchronization of C (High-level Data Link Control Procedure) method is performed.
Here, a packet configuration example in that case is shown.

In FIG. 9, 901 is flag data indicating the start and end of the packet, 902 is address data indicating the destination, 903 and 904 are control command data indicating the type of packet, and 905 is reception mode information according to the present invention. And reception mode data having other control information, and 906 is a flag check sequence (FCC) for detecting packet errors, such as a parity code or CRC (Cyclic R).
edundancy Check Code) is used.

FIG. 9A shows an example in which the reception mode data is sent to the transmission side as an independent packet. In the control command 903, this packet is a packet for the reception mode information and other control information. By setting a command indicating that there is, the reception mode data 905 is transmitted in an independent packet. FIG. 9B shows an example of a packet in which the reception mode data 905 is sent together with the image data 907 to be transmitted. In this case, the control command 904 includes the reception mode data 905 and the transmission image data 907 in this packet. Set the command to indicate that you are out.

Next, a fifth embodiment of the present invention will be described with reference to FIG. In the fifth embodiment, a still image is sent at the same time as a moving image is sent, and it takes much longer to send one still image than to send only a still image, but the moving image has a high definition. High-definition still images can be sent at the same time when high-quality images cannot be sent.
It is easy to use. Also, watching the video,
If you want to view it as a still image, you can send a freeze image by issuing a freeze instruction on the receiving side.

(1) of FIG. 10 is a diagram showing a packet structure for realizing this function. A moving picture packet 1001 for sending moving picture data and a still picture packet 1002 for sending still picture data.
Is an independent packet, and the still image packet 1002 is sent while one or more moving image packets 1001 are sent. 10B shows a configuration example of the moving image packet 1001, and FIG. 10C shows a configuration example of the still image packet 1002, showing a packet configuration of flag synchronization by the HDLC method. In (2) and (3) of FIG. 10, 1003 is flag data indicating the start and end of the packet, 1004 is address data indicating the destination, 1005 and 1006 are control commands indicating the attributes of the packet, and the control command 1005 Is set to command data indicating that it is a packet of moving image data 1007, and command data indicating that it is a packet of still image data 1008 is set to the control command 1006. Reference numeral 1009 is a frame check sequence (FCC) that performs error detection and the like.

FIG. 11 is a diagram showing an example of another packet structure for transmitting a moving image and a still image at the same time. This is to send moving image data and still image data at the same time in one packet. The same parts as those in FIG.
Reference numeral 1 is control command data for setting a command indicating that this packet is a packet in which moving image data and still image data are mixed.

Here, in the examples of FIGS. 10 and 11, the ratio of moving image data to still image data may be any ratio, for example, 100 bytes of moving image data may be 1 byte of still image data. Alternatively, one frame of still image data may be provided for 10 frames of moving image data, or 8 lines of still image may be provided for 10 frames of moving image data. To set the mode in which a moving image and a still image are simultaneously sent as shown in FIGS. 10 and 11, for example, (1) in FIG.
In FIG. 8, each time the button 802 is pressed, the mode is switched to the moving image mode → still image mode → simultaneous reception mode, or in FIG. 8 (2), a button for the simultaneous reception mode may be further provided.

In each of the embodiments shown in FIGS. 1, 5, 6 and 7, a display such as a camera or a monitor display may be built-in or externally connected. Needless to say. Further, in the above description, the image transmission device using the analog telephone line as the communication line is taken as an example, so that the modems 503, 603, 703 are necessary in the embodiments of FIGS. 5, 6 and 7. However, in the case of an image transmission device for digital lines such as ISDN lines, such a modem is unnecessary.

[0039]

As described above, according to the present invention, in an image transmission device such as a videophone, the image received by the receiving side can be freely switched to a moving image or a still image, and the received still image can be switched. Since it is possible to switch to a moving image and display the moving image at the same time while displaying, it is very convenient.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of an image transmission system constructed by two image transmission devices according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an example of a display screen according to each embodiment of the present invention.

FIG. 3 is an explanatory diagram showing another example of a display screen according to each embodiment of the present invention.

FIG. 4 is an explanatory diagram showing still another example of the display screen according to each embodiment of the present invention.

FIG. 5 is a block diagram showing an image transmission device according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing an image transmission device according to a third embodiment of the present invention.

FIG. 7 is a block diagram showing an image transmission device according to a fourth exemplary embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an example of an operation unit as a received image selection unit used in each embodiment of the present invention.

FIG. 9 is an explanatory diagram showing an example of a packet configuration for transmitting reception mode data used in the first to fourth exemplary embodiments of the present invention.

FIG. 10 is an explanatory diagram showing an example of a packet configuration used when transmitting moving image data and still image data at the same time, which is used in the fifth embodiment of the present invention.

FIG. 11 is an explanatory diagram showing another example of a packet configuration when transmitting moving image data and still image data at the same time.

[Explanation of symbols]

 103, 104 camera 105, 106 still image transmission processing unit 107, 108 moving image transmission processing unit 109, 110 transmission changeover switch 111, 112 communication line 113, 114 reception changeover switch 115, 116 still image reception processing unit 117, 118 moving image reception process Part 119, 120 Composite processing part 121, 122 Monitor display 123, 124 Operation part 201, 301, 401 Received still image 202, 302, 402 Received moving image

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Masatoshi Miyakoshi, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Hitachi, Ltd. Multimedia system development headquarters

Claims (5)

[Claims] 1. An image transmission device for transmitting and receiving images via a line, comprising: still image transmission processing means for compressing and encoding still images; moving image transmission processing means for performing compression and encoding of moving images; Transmission switching means for switching and transmitting image data from the still image transmission processing means and the moving image transmission processing means, a still image reception processing means for performing decoding as a still image, and a moving image for performing decoding as a moving image. Receiving processing means and reception switching means for switching the received image data and supplying it to the still image receiving processing means or the moving image receiving processing means are provided, and the moving image is transmitted while the still image is transmitted by the still image transmitting processing means. The still image reception processing means while receiving a moving image by the reception processing means or transmitting the moving image by the moving image transmission processing means. Thus the image transmission apparatus characterized by capable of receiving a still image. 2. The receiving image selecting means for switching between a still image and a moving image as a receiving image according to claim 1, and instructing the transmitting side of the type of the image selected by the receiving image selecting means. An image transmission apparatus comprising: a reception mode communication unit that receives a type of a received image instructed by a partner, and the type of image to be received can be selected by operating the received image selection unit on the receiving side. 3. The image transmission device according to claim 1, wherein the transmission switching unit and the reception switching unit are appropriately switched to simultaneously transmit a moving image and a still image by a time division multiplexing method. 4. The combination processing unit according to claim 1, 2 or 3, wherein a combination processing unit for combining and displaying a plurality of images on one screen is provided, and the still image reception processing unit and the moving image reception processing unit are provided by the combination processing unit. An image transmitting apparatus, characterized in that the images received in step 1 are combined and displayed on one screen. 5. The moving image received by the moving image receiving means and the received image freezing means provided with a received image freezing means for freezing the moving image received by the moving image receiving means into a still image. An image transmission device characterized in that the still image frozen in the above step is combined into one screen by the combining processing means.