JP2001197460A - Image data relaying method and communication management center - Google Patents

Abstract

PROBLEM TO BE SOLVED: To convert image data to a low resolution in accordance with the resolution of a display device in the transmission destination, when relaying image data in a communication management center to which plural communication terminal devices are connected. SOLUTION: With respect to an image data relaying method in the communication management center, to which plural communication terminal devices are connected, the communication management center temporarily stores image data transmitted from communication terminal devices and converts stored image data to a low resolution according to the resolution of the display device of the communication terminal device in the transmission destination and transmits image data of the low resolution obtained by this conversion to the communication terminal device in the transmission destination.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for relaying image data and a communication management center, and is used for relaying communication by a portable communication terminal device for performing image communication, for example, a portable videophone.

[0002]

2. Description of the Related Art Hitherto, a communication terminal device capable of transmitting and receiving voice and images has been proposed for use in a wired or wireless video telephone, a video conference system, or another image communication system.

[0003] In these communication terminal devices, an image of a subject captured by a camera is transmitted as a still image or a moving image, but the image data is compressed with high efficiency in order to save communication charges. In particular, in the case of a videophone, the display surface of the display device is made relatively small in order to reduce the size of the device and simplify the operation. By using a personal computer and connecting a camera and a telephone or audio equipment to the personal computer, the personal computer can be used as a communication terminal for a videophone or videoconference.

Further, there has been proposed a communication terminal device including a headset for a telephone call, a memory card storing image data captured in advance, a liquid crystal display device, etc., and transmitting image data together with voice (Japanese Patent Laid-Open No. Hei 6-1994). No. 261167).

[0005] When communication is performed by these communication terminal devices, a communication management center that performs relaying performs various exchange control for data exchange.

[0006]

When performing image communication using the various communication terminal devices described above, the size of the display surface of the display device differs depending on the device of the communication partner, and the resolution of display is thereby reduced. Various.

Therefore, when transmitting image data from the communication terminal device, the resolution of the image data to be transmitted may be higher than the resolution of the communication partner. In that case, the image protrudes from the display surface of the communication partner, making it difficult to view, and the communication fee is further increased due to the large data amount. In the case of a portable communication terminal device,
There is also a problem that the use time of the apparatus is shortened because the battery is wasted.

[0008] Conventionally, the communication management center only relays image data, and does not perform conversion or control in accordance with the resolution of the display device of the communication terminal device. The present invention has been made in view of the above-described problems, and when relaying image data at a communication management center to which a plurality of communication terminal devices are connected, the image data is transmitted according to the resolution of a display device at a transmission destination. An object of the present invention is to reduce the amount of communication data by converting to a low resolution.

[0009]

According to a first aspect of the present invention, there is provided a method of relaying image data in a communication management center to which a plurality of communication terminal devices are connected, wherein the communication management center includes a communication terminal device. Temporarily storing the image data transmitted from the communication terminal device, and transmitting the stored image data to the communication terminal device, converting the image data to a low resolution according to the resolution of the display device of the communication terminal device of the transmission destination, and converting the image data. The low-resolution image data obtained by the above is transmitted.

The communication management center according to the invention of claim 2 is
A communication management center to which a plurality of communication terminal devices are connected and which transmits and receives image data to and from each communication terminal device, wherein a display resolution detection unit that obtains information on a resolution of a display device of the communication terminal device; A resolution conversion unit that converts image data transmitted from the communication terminal device to a low resolution based on the information about the resolution acquired by the display resolution detection unit; and a low-resolution image obtained by the conversion in the resolution conversion unit. And a transmission unit for transmitting data.

In the communication management center according to the third aspect of the present invention, there is provided a display resolution table storing the address of each communication terminal device and the resolution of the display device in association with each other. Refer to the display resolution table to obtain information about the resolution.

In the communication management center according to a fourth aspect of the present invention, the display resolution detecting section acquires information on the resolution of the display device of the communication terminal device based on the attribute information of the image data received from the communication terminal device. I do.

[0013] In the communication management center according to a fifth aspect of the present invention, the display resolution detecting section acquires information on the resolution of the display device of the communication terminal device based on the resolution of the image data received from the communication terminal device. .

[0014] In the communication management center according to the invention of claim 6, the display resolution detecting section acquires information on the resolution of the display device of the communication terminal device based on the type information received from the communication terminal device.

The communication management center according to the invention of claim 7 is:
A communication management center to which a plurality of communication terminal devices are connected and which transmits and receives image data to and from each communication terminal device, wherein a storage means for storing a plurality of image data transmitted from the communication terminal devices; A display resolution detection unit that obtains information about the resolution of the display device of the device, and converts the designated image data of the stored image data to a low resolution based on the information about the resolution obtained by the display resolution detection unit. A resolution conversion unit, and a transmission unit that transmits the low-resolution image data obtained by the conversion in the resolution conversion unit to a communication terminal device that has designated it.
Having.

[0016]

FIG. 1 is a block diagram showing an overall outline of a communication system 1 including a communication management center according to the present invention.

In FIG. 1, a communication system 1 includes a communication management center 10, wireless base stations 11a, 11b, portable terminals 12a, 12b, wirelessly connected to these wireless base stations 11a, 11b,. 13a, 13b ...,
And the line CL is connected to these wired base stations 13a, 13b.
Are connected by terminal devices 14a, 14b,...

As the line CL, a public line, a dedicated line,
Various lines such as an SDN line are used. Also, LA
It is also possible to connect via various networks such as N, WAN, and the Internet. .. May be referred to as “wireless base station 11” in any or all of the wireless base stations 11a, 11b. The same applies to other cases.

The communication management center 10 includes a wired communication management center 10a and a wireless communication management center 10b. Wired communication management center 10a and wireless communication management center 10
b communicates with each other and manages communication by performing communication control and exchange control so that the entire wireless base station 11 and the wired base station 13 can communicate with each other.

The portable terminal 12 is a digital telephone capable of data communication. A camera is mounted and can be used as a videophone. In addition, image data obtained by imaging (photographing) can be transmitted to another mobile terminal 12 or the terminal device 14 or the like. This will be described later in detail.

The terminal device 14 is, for example, an analog telephone, a modem, a digital terminal device, or another communication terminal for data communication, and can transmit and receive a voice signal or data through the line CL.

A personal computer 15 is connected to the terminal device 14a. Personal computer 15
Is equipped with a video capture board, and an image captured by the video camera 16a is captured as image data. Further, a microphone and a speaker (not shown) are also connected, so that they can be used as a videophone.

The terminal device 14b has a digital camera 16b
Is connected, and image data captured by the digital camera 16b can be transmitted to another terminal device 14 or the portable terminal 12.

The portable terminal 17 is connected to the terminal device 14c. The mobile terminal 17 is similar to the mobile terminal 12, but has no communication function and performs communication via the terminal device 14c. It performs transmission and reception of e-mail and the like, transmission and reception of captured image data, and the like.

FIG. 2 is a block diagram showing an example of the configuration of the portable terminal 12, FIG. 3 is a perspective view showing an example of the appearance of the portable terminal 12,
4 is a diagram for explaining resolution control by read control of the image sensor 32, FIG. 5 is a diagram showing an example of a display resolution table TB1, and FIG. 6 is a diagram showing an example of transmission data DTS transmitted from the portable terminal 12. .

Referring to FIG. 2 and FIG.
Are an imaging unit 30, a display unit 40, an image data processing unit 50,
System control unit 60, operation keys 61, antenna 62, RF unit 63, audio / image multiplexing / decomposing unit 64, audio codec 65, audio I / O unit 66, speaker 67, microphone 68, power supply device 69, and It is composed of a stored or mounted body BD or the like.

The imaging section 30 includes a lens 31, an imaging sensor 3
2, an imaging control unit 33, an imaging memory 34, and the like. The image sensor 32 is a CCD or CMOS area-type digital image recording element. For example, 1.4 million pixels (1400 × 1
000 pixels).

The image pickup control section 33 has a readout resolution of the image pickup sensor 32 and an image pickup time (integration time) in accordance with the image pickup mode specified by the system control section 60.
Control and so on. The imaging memory 34 stores image data captured by the imaging sensor 32 and attribute information thereof.

That is, the imaging control unit 33 controls the imaging sensor 3
2 by controlling the reading of
Stores low-resolution image data corresponding to the resolution of the display device of the communication partner. The imaging control unit 33 can perform various controls as readout control.

For example, as readout control, pixel thinning control is performed. For example, as shown in FIG. 4A, in every direction of the row and the column of the image sensor 32, one for every four pixels.
The image data is thinned out so that the image data is extracted at a pixel ratio. As a result, the image data having the resolution of 1/16 is stored in the imaging memory 34.

As shown in FIG. 4B, by extracting image data at a rate of one pixel for every two pixels in both the row and column directions of the image sensor 32, Image data whose resolution is reduced to a quarter is stored.

In the read control, instead of performing the thinning process as described above, for example, FIG.
Taking the case of example as an example, the average value of 16 image data is calculated, and the average value is set as image data representing 16 pixels. Further, 16 image data are added, and the total value is used as image data representing 16 pixels. If the addition is performed, the image is bright even when the subject is dark, which is convenient when the light amount is insufficient or when it is desired to increase the imaging speed. Also, noise is reduced.

As shown in FIG. 3, a part of the imaging section 30 including the lens 31 is provided on the upper part of the main body BD of the portable terminal 12 so as to be rotatable left and right and up and down so as to change the imaging direction. I have. When the user using the mobile terminal 12 captures an image of himself / herself, the arm may be slightly extended while holding the main body BD by hand, and the imaging unit 30 may be slightly away from the body and turned toward the face. The image captured by the imaging unit 30 is displayed on the LCD 41, and the user may adjust the attitude of the imaging unit 30 while watching the image.

To make a telephone call in this state, speak a little loudly toward the microphone 68. Louder sound is output from the speaker 67. Earphones may be used.

The display section 40 comprises an LCD 41, a display data memory 42 and the like. The LCD 41 is, for example, 32
It is a color LCD of 0 × 240 pixels and displays received image data, transmitted image data, messages, communication status, and other information. The display data memory 42 temporarily stores display data.

The image data processing unit 50 includes a data conversion unit 5
1, an image data correction unit 52, a resolution conversion unit 53, and the like. The data converter 51 decompresses image data sent from a communication partner and compresses image data for transmission.

The image data correction unit 52 converts the image data sent from the communication partner into color data suitable for display on the LCD 41 of the apparatus. Further, the image data is converted into image data of a color balance set according to the user's preference. The image data captured by the image capturing unit 30 is also subjected to optimal correction after determining its state.

The resolution conversion unit 53 converts the received image data into an L based on the setting of the imaging mode in this apparatus.
The resolution conversion according to the CD 41 is performed. As the resolution conversion processing, the resolution is reduced by thinning out the image data, and the resolution is increased by interpolating the image data.

The resolution conversion section 53 reduces the resolution of image data for transmission in accordance with the imaging mode specified by the system control section 60 and converts the image data into low-resolution image data. Normally, the system control unit 60 controls the imaging control unit 33 to generate image data having a desired resolution. However, it is also possible to control the resolution conversion unit 53.

In this case, the resolution converter 53 can be used for both the resolution conversion of the received image data and the resolution conversion of the image data to be transmitted. And contributes to cost reduction.

As a method for resolution conversion in the resolution conversion unit 53, for example, nearest neighbor interpolation (nearest neighbor), bilinear interpolation (bilinear), tertiary convolution interpolation (cubic convolution or Various known methods such as (bicubic) can be used.

The system control unit 60 has a display resolution table TB referred to for setting an imaging mode.
1 is provided. As shown in FIG. 5, the display resolution table TB1 stores the address AR of the communication partner and the resolution (display resolution) KD of the display device in association with each other. In this example, the telephone number of the communication partner is recorded as the address of the communication partner. Instead of a phone number,
A URL (Uniform Resource Locator), an e-mail address, an IP address, and the like may be recorded.

These data are stored in the operation key 61 by the user.
And automatically records information acquired by communication or obtained by communication. By providing the display resolution table TB1, it is possible to easily and quickly obtain the display resolution KD of the communication partner.

When a communication partner is called from the portable terminal 12, the display resolution KD is acquired with reference to the display resolution table TB1. For the communication partner not recorded in the display resolution table TB1, the display resolution KD of the communication partner is obtained by the following various methods. (1) Obtain the display resolution KD according to the protocol for establishing a call. (2) The display resolution KD is obtained based on information sent from the communication partner such as the type of the device of the communication partner. For example, in a personal computer, a portable terminal, a portable videophone, and the like, the display resolution KD is estimated according to the standard size of the display device depending on the type. (3) The display resolution KD is estimated from the resolution of the image data sent from the communication partner. For example, the resolution of the sent image data is estimated as the display resolution KD. Alternatively, it is assumed that the resolution is lower than the resolution of the transmitted image data.

In addition, the system control unit 60 controls the entire portable terminal 12. As shown in FIG.
The operation keys 61 include a numeric keypad TK, an up key UK,
It has a down key DK, a function key FK, and the like. A telephone number is input using the numeric keypad TK. The function key FK is used to switch between a call mode, an image communication mode, a display mode, an imaging mode, and the like. With the up key UK and the down key DK, the presence / absence of just size display, the presence / absence of resolution control, setting of other states, the zoom operation of the imaging unit 30, and the like are performed. The system control unit 60 issues a command according to the operation content of the operation key 61.

Returning to FIG. 2, the antenna 62 transmits and receives radio waves. The RF unit 63 performs amplification, modulation, demodulation, and the like of a high-frequency signal. The audio / image multiplexing / decomposing unit 64 performs multiplex synthesis of audio data and image data, and also decomposes the synthesized data. The audio codec 65 expands the compressed audio data. Also, the audio data input from the microphone 68 via the audio I / O unit 66 is compressed. The audio I / O unit 66 converts the audio data into an audio signal and outputs it from the speaker 67 as audio. Also,
The audio signal from the microphone 68 is converted into audio data. The power supply device 69 includes a battery and a DC-DC converter, and supplies power to the entire portable terminal 12.

The communication management center 10 has the above-mentioned functions, and further has the following functions. FIG.
3 is a block diagram illustrating an example of a function of the communication management center 10. FIG.

In FIG. 7, the communication management center 10 includes a transmission / reception unit 71, a modulation / demodulation unit 72, an audio / image multiplexing / decomposing unit 73, a data conversion unit 74, an image conversion unit 75, a display resolution detection unit 76, and a memory 77. , And a display resolution table TB2.

The transmission / reception unit 71 performs transmission / reception for data relay. The data conversion section 74 expands and compresses data. The image conversion unit 75 performs resolution conversion in the resolution conversion unit 75a, and also performs color conversion and the like. The display resolution detection unit 76 detects the display resolution KD of the mobile terminal 12 or the terminal device 14 that communicates with the communication management center 10. Various methods are used for detecting the display resolution KD.

For example, reference is made to the display resolution table TB2, acquired from the header HD of the transmission data DTS, acquired by pre-communication processing when the communication partner is a new communication partner, or acquired from the transmission source to the partner. For example, there is a method of acquiring based on the resolution. In particular, in the case of a videophone, several to several tens of image data are transmitted and received every second. Therefore, it is necessary to estimate the resolution of the source display device from the resolution of one image data transmitted first. Is possible.

In order to perform these processes, transmission data is temporarily stored in the memory 77. In this storage, not all of the transmission data is stored at the same time, but a part thereof may be stored instantaneously.

Next, the operation and operation when making a videophone call using the portable terminal 12 will be described. A call is made to the other party's mobile terminal 12 or terminal device 14 by operating the numeric keypad TK or the like. When the call is established and the line is connected, a call can be made with the microphone 68 and the speaker 67. At the same time, the image data captured by the imaging unit 30 is transmitted to the other party, and the image is displayed on the other party's display device. The image data transmitted from the other party is displayed on the LCD 41. The LCD 41 is provided with a small window, on which a monitor image of the image data captured by the imaging unit 30 is displayed. If image data is not sent from the other party, the image data captured by the image capturing unit 30 can be displayed on the LCD 41 in a large size.

As shown in FIG. 6, the transmission partner DTS is the transmission data DTS obtained by adding the header HD to the image data DTG.
Is sent. In the header HD, the resolution of the LCD 41,
The resolution of the image data DTG and other information are recorded as attribute information. As a result, the communication partner can acquire the resolution of the LCD 41 of the portable terminal 12 that is the transmission source. The image data DTG is compressed data such as JPEG.

When the just size display mode is set, the image data transmitted from the other party is
The resolution is converted, that is, reduced according to the resolution of the LCD 41. In the resolution conversion, the image is converted so that the aspect ratio of the image is maintained and the image is completely displayed on the display surface of the LCD 41. However, when the original image data is lower than the resolution of the LCD 41, simple enlargement of the image is not performed. This is because simply enlarging the image makes it hard to see.

When transmitting image data from the portable terminal 12 to the communication partner, the resolution of the image data to be transmitted is set to low-resolution image data corresponding to the resolution of the display device of the communication partner.

For this purpose, the system control unit 60
Acquires the display resolution KD of the communication partner with reference to the display resolution table TB1. For a communication partner not recorded in the display resolution table TB1, VGA (Video
1/4 resolution of Graphics Array) (320 × 240
Pixel). In the case of not a videophone, image data of a set resolution is transmitted. If no resolution is set, the highest resolution is usually set as the default value.

As a method for obtaining such low-resolution image data, the imaging control unit 33 controls the reading of the imaging sensor 32 as described above. In the method of obtaining low-resolution image data by controlling the readout of the image sensor 32, the energy required for data transfer from the image sensor 32 is small, and the power consumption is reduced and the battery life is improved. Further, since the data amount of the image data is reduced, the processing time is short. In the flowchart described later, the reading control of the image sensor 32 is performed by:
This is performed in the low-resolution imaging mode.

Further, as described above, the image sensor 3
It is also possible to read out at the maximum resolution without thinning out when reading from 2, and convert it to a lower resolution in the resolution converter 53.

Next, an example of processing and operation of the communication system 1 will be described with reference to a flowchart. First, the processing operation of the mobile terminal 12 will be described.

FIG. 8 is a flowchart showing a start process of the portable terminal 12, FIG. 9 is a flowchart showing a terminal state setting process, FIG. 10 is a flowchart showing a display mode setting process, and FIG. 12 is a flowchart showing a videophone process, FIG. 13 is a flowchart showing a television initial setting process, and FIG.
4 is a flowchart showing terminal imaging mode processing, FIG.
Is a flowchart showing another example of the terminal imaging mode process,
FIG. 16 is a flowchart showing a data transmission process.
Is a flowchart showing a data receiving process, and FIG. 18 is a flowchart showing an image resolution converting process.

In the activation process shown in FIG. 8, when the portable terminal 12 is activated by operating the operation key 61 from the standby state, the purpose of the activation is analyzed based on the state of the pressed key and the like. Is performed according to.

That is, if the terminal is activated for state setting (YES in # 11), terminal state setting processing is performed (# 16). If activated in the videophone mode (Yes in # 12), videophone processing is performed (# 1).
5). If activated in the voice call mode (# 1
Then, the voice communication process is performed (# 14). If neither of these is the case, a standby state is entered.

In the terminal state setting process shown in FIG. 9, the user sets the display mode and the imaging mode in advance. Before the setting is performed, it is set to a predetermined initial state. A display mode setting process is performed (# 21), and an imaging mode setting process is performed (# 22).

In FIG. 10, the user determines whether or not to set the just size display mode (# 31), and if so, sets the flag JUSTS to "1"(# 31).
32) If not set, set flag JUSTS to “0”
(# 33).

In the just-size display mode, when the resolution of the received image data is larger than the resolution of the LCD 41, the image data is reduced according to the resolution of the LCD 41 and displayed. Therefore, in the just size display mode, all of one page of the received image data is simultaneously displayed on the display surface of the LCD 41 without scrolling.

As described above, by setting a preferred display mode in advance, it is not necessary to make cumbersome settings each time communication is performed. In FIG. 11, the user determines whether or not to set the low-resolution imaging mode (# 41), and if so, sets the flag TEIKAI to “1” (# 41).
42) If not set, the flag TEIKAI is set to "0"(# 43).

In the initial state, both the flag JUSTS and the flag TEIKAI are set to "1". In FIG. 12, a connection with a communication partner is established by dial connection (# 51). The subroutine of the TV initial setting is called to perform the initial setting of the video phone mode (# 5)
2). The terminal data receiving process and the terminal data transmitting process are performed in parallel (# 53, # 54). These operations are two C
It may be performed by a PU or by interrupting one CPU. These processes are repeated until the communication connection is terminated (# 55).

In FIG. 13, a radio wave from a communication partner is received (# 61). The received radio wave is demodulated and data is extracted (# 62). The extracted data is decomposed into audio data and image data (# 63). When attribute information is included in the header HD or the like, the attribute information is also separated and extracted. Then, a subroutine of the terminal imaging mode processing is called to set the imaging mode.

In the terminal imaging mode processing shown in FIG. 14, the actual imaging method is determined from the resolution (display resolution) KD of the display device of the communication partner and the setting state of the low-resolution imaging mode described above.

In FIG. 14, the display resolution K of the communication partner is shown.
The data of D is taken in (# 71). Note that the display resolution KD may be acquired based on system data. Alternatively, when there is no system data, the display resolution KD is expanded by expanding the image data transmitted first.
May be estimated. In this case, for example, it is estimated that the resolution of the transmitted image data substantially matches the display resolution KD.

Then, the flag TEIKAI is confirmed, and if it is "0", that is, if the low-resolution imaging mode is not set (Yes in # 72), the standard imaging mode is set (# 75). In the standard imaging mode, the imaging sensor 3
Imaging is performed at the maximum resolution of 2. However, the resolution in the standard imaging mode can be separately set.

Even if the flag TEIKAI is "1",
That is, even if the low-resolution imaging mode is set (No in # 72), if the display resolution KD of the communication partner is high, that is, if the display resolution KD of the communication partner is V
If the size is equal to or larger than the GA size (640 × 480 pixels), image pickup is actually performed in the standard image pickup mode (# 75). VG
If the size is smaller than the A size, it is determined that transmission of high-quality image data is unnecessary, and an image is actually taken in the low-resolution imaging mode (# 74).

In step # 71, the display resolution KD may be determined from the display resolution table TB1 provided in the system control unit 60, instead of taking in the data of the display resolution KD of the communication partner. That is,
The telephone number of the communication partner currently communicating is retrieved from the display resolution table TB1, and the display resolution KD corresponding to the telephone number is read. If it is not recorded in the display resolution table TB1, the user is informed that fact. In that case, for example, the user manually inputs the resolution. The input resolution is registered in the display resolution table TB1, and the data can be used from the next time.

In the terminal imaging mode processing shown in FIG. 15, when the low-resolution imaging mode is set (No in # 81), the user is asked to confirm it, and if the user gives an instruction of consent (# 82). Yes), the low-resolution imaging mode is actually set (# 83). If the low-resolution imaging mode is not set, and if the user does not give an instruction for consent even if the low-resolution imaging mode is set, the standard imaging mode is set (# 8).
4). In order to indicate whether or not the user has accepted, for example, an appropriate button may be displayed on the display surface, or a specific operation key may be operated.

In the terminal data transmission process shown in FIG. 16, the image data captured by the image sensor 32 and the audio data input from the microphone 68 are combined to transmit data. That is, imaging (integration) of the imaging sensor 32 is started according to the set imaging mode (# 91). A voice is input from the microphone 68 (# 92). It is determined whether or not the integration of the image sensor 32 has been completed. If not, the process jumps to step # 97.

If the integration of the image sensor 32 has been completed,
The image data is taken in (# 94), the brightness or color of the image data is corrected (# 95), and the image data is compressed (# 96).

Then, the previously fetched audio data and image data are multiplexed and synthesized (# 97). After performing data modulation in the RF unit 63 (# 98), the data is transmitted as radio waves (# 99).

In the terminal data receiving process of FIG. 17, the received radio wave is decomposed into audio data and image data, and data display and audio output are performed. That is, a radio wave is received (# 111) and demodulated as reception data (# 1).
12). Decompose into audio data and image data (# 11
3). Since the received image data is compressed, it is decompressed (# 114) and corrected for color or brightness (# 115). Then, a subroutine for image resolution conversion processing is called, and resolution conversion is performed in accordance with the settings in order to display the image on the LCD 41. By writing the converted image data in the display data memory 42, the LCD 4
1 (# 117).

Since the received voice data is also compressed, it is decompressed (# 118), converted into a voice signal, and the voice is output from the speaker 67. In FIG.
Check the resolution (size) of the received image data (#
131). The size of the received image data is larger than the size of the display surface of the LCD 41 of the mobile terminal 12 (#
132, and when the just size display mode is set (No in # 133), the image data is set to L
The resolution conversion is performed to match the resolution of the CD 41 (# 13
4). Otherwise, return as is.

Next, the processing operation of the communication management center 10 will be described. In this example, an image conversion service that is effective when the image processing capability of the portable terminal 12 is low and when it is desired to suppress battery consumption will be mainly described.

FIG. 19 is a diagram showing a main flowchart of the communication management center 10, FIG. 20 is a flowchart showing center communication pre-processing, FIG. 21 is a flowchart showing communication connection processing, and FIG. 22 is a flowchart showing center image conversion processing. .

In FIG. 19, first, it is confirmed whether or not a new connection has been made (# 201). If there is a new connection, the center communication pre-processing is performed (# 204), and if there is no new connection, the ongoing communication connection processing is performed (# 20).
2). This is repeated as long as there is a connection (# 203). If there is no connection at all, it shifts to the standby state.

The center communication pre-processing shown in FIG. 20 catches information from terminals communicating with each other, confirms whether there is a request to the communication management center 10, and prepares to respond to the request if there is one. Is a subroutine for performing

That is, the information (including the request) of the communication terminal A on the calling side is caught and confirmed (#
211). This information includes the imaging resolution, display device resolution (display resolution KD), model (type of personal computer, portable terminal, portable videophone, etc.), presence / absence of image conversion request (resolution, color correction, etc.). ing. These pieces of information are recorded, for example, in the header HD.

Then, the information (including the request) of the communication terminal B on the receiving side is caught and confirmed (# 21).
2). It is confirmed whether or not either side is the portable terminal 12, that is, whether or not it is a portable videophone (# 21).
3). If it is not a portable videophone, the process returns.

If it is a portable videophone (Yes in # 213) and there is an image conversion request to the communication management center 10 (Yes in # 214), the center image conversion setting is performed (# 215). Here, for example, a flag for that purpose is set. Note that both the communication terminals A and B are checked and the settings are made for each.
There are two image conversion requests, a resolution conversion request and a color conversion request.

In this example, the service is set to be provided only to a portable videophone having a low image conversion capability. If the communication management center 10 has enough capacity,
It may be expanded to other models.

In FIG. 21, while confirming whether or not the center image conversion setting has been made for each communication connection (# 225), the center image conversion processing is performed for the communication for which the center image conversion setting has been made. (# 2
26). This process is repeated for all communication connections.

In the center image conversion process shown in FIG. 22, the communication management center 10 performs image conversion on communication for which center image conversion setting has been made. For example, when communication is performed between a portable videophone having a low image conversion capability and a terminal using a high-speed personal computer, when the center image conversion is performed on data received by the portable videophone, The processing load on the telephone is reduced, and smooth communication can be performed.

In FIG. 22, communication radio waves are caught (# 231) and data is demodulated (# 232). It is decomposed into audio data and image data (# 233), and the compressed image data is decompressed (# 234).

If there is a resolution conversion request (Yes in # 235) and the resolution of the image data is larger than the resolution of the display device (Yes in # 236), the image data is converted (reduced) to low-resolution image data. Yes (# 23
7). If there is a color conversion request (Yes in # 238), the image data is color-converted (# 239).

Then, the image data is recompressed (# 24
0), multiplex and resynthesize the audio data and the image data (#
241), and perform data modulation (# 242). In the above-described embodiment, the case where the communication management center 10 performs the exchange control between the communication terminal devices has been described. For example, the communication management center 10
Can be used as a server on the Internet.

In this case, pictures, CG, and other images are transferred from a communication terminal device such as a personal computer to the memory 7 of the communication management center 10 via the Internet.
7, and the images can be downloaded to the communication terminal device upon request.

When requesting an image, the communication terminal device specifies a specific image and notifies the resolution of the display device of the communication terminal device. The resolution of the display device may be input by a user operation, or may be automatically acquired and transmitted by a system program of the communication terminal device.

The communication management center 10 detects the notified resolution by the display resolution detecting unit 76, converts the resolution of the specified image based on the detected resolution, and sends it to the communication terminal device that has requested it. Send. When the resolution of the communication terminal device is registered in the display resolution table TB2 of the communication management center 10, it can be obtained from the registered resolution.

As described above, by converting the image data in the communication management center 10 according to the resolution of the communication terminal device and transmitting the image data to the communication terminal device, the processing load on the communication terminal device is reduced. Normally, high-resolution image data is stored in the memory 77 of the communication management center 10, and the resolution of the communication terminal device is considerably lower than that. As a result, the amount of data transmitted on the network is greatly reduced, and communication time and communication cost are reduced.

In the above-described embodiment, the configuration of the communication management center 10, the mobile terminal 12, the terminal device 14, or the whole or each part of the communication system 1, the contents of processing, the order, and the like are in accordance with the gist of the present invention. It can be changed as appropriate.

[0098]

According to the present invention, when relaying image data at a communication management center to which a plurality of communication terminal devices are connected, the image data is converted to a low resolution in accordance with the resolution of the display device of the transmission destination. Thereby, the data amount of communication is reduced.

Therefore, the processing load on the communication terminal device is reduced, and when the communication terminal device is portable, useless consumption of the battery is suppressed. According to the invention of claim 3,
The resolution of the display device of the communication terminal device can be easily acquired at high speed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall outline of a communication system using a communication terminal device according to the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a mobile terminal.

FIG. 3 is a perspective view showing an example of the appearance of the portable terminal.

FIG. 4 is a diagram for explaining resolution control by read control of the image sensor 32;

FIG. 5 is a diagram illustrating an example of a display resolution table.

FIG. 6 is a diagram illustrating an example of transmission data transmitted from a mobile terminal.

FIG. 7 is a block diagram illustrating an example of a function of a communication management center.

FIG. 8 is a flowchart illustrating a start process of the portable terminal.

FIG. 9 is a flowchart showing a terminal state setting process.

FIG. 10 is a flowchart showing a display mode setting process.

FIG. 11 is a flowchart illustrating an imaging mode setting process.

FIG. 12 is a flowchart showing a videophone process.

FIG. 13 is a flowchart showing a television initial setting process.

FIG. 14 is a flowchart illustrating a terminal imaging mode process.

FIG. 15 is a flowchart illustrating another example of the terminal imaging mode process.

FIG. 16 is a flowchart illustrating a data transmission process.

FIG. 17 is a flowchart illustrating data reception processing.

FIG. 18 is a flowchart illustrating image resolution conversion processing.

FIG. 19 is a diagram showing a main flowchart of the communication management center.

FIG. 20 is a flowchart showing a center communication pre-process.

FIG. 21 is a flowchart illustrating communication connection processing.

FIG. 22 is a flowchart illustrating a center image conversion process.

[Explanation of symbols]

 Reference Signs List 1 communication system 10 communication management center 12 portable terminal (communication terminal device) 14 terminal device (communication terminal device) 41 LCD (display device, display unit) 71 transmission unit 75a resolution conversion unit 76 display resolution detection unit 77 memory TB2 display resolution table HD header (attribute information) DTG image data

Continued on the front page F term (reference) 5C062 AA12 AA14 AA21 AA37 AB42 AC08 AC24 AC29 AC43 BA00 BB03 5C064 AA01 AA02 AC04 AC08 AC12 AD02 AD14

Claims (7)

[Claims] 1. A method for relaying image data in a communication management center to which a plurality of communication terminal devices are connected, wherein the communication management center temporarily stores and stores image data transmitted from the communication terminal device. When transmitting the image data to the communication terminal device, the image data is converted to a low resolution according to the resolution of the display device of the communication terminal device of the transmission destination, and the low-resolution image data obtained by the conversion is transmitted. A method of relaying image data. 2. A communication management center to which a plurality of communication terminal devices are connected and which transmits and receives image data to and from each communication terminal device, wherein a display resolution for acquiring information relating to a resolution of a display device of the communication terminal device. A detection unit; a resolution conversion unit configured to convert image data transmitted from the communication terminal device to a low resolution based on the information regarding the resolution acquired by the display resolution detection unit; And a transmitting unit for transmitting the low-resolution image data. 3. A display resolution table storing an address of each communication terminal device and a resolution of a display device in association with each other, wherein the display resolution detection section refers to the display resolution table to obtain information on resolution. The communication management center according to claim 2, wherein: 4. The communication management center according to claim 2, wherein the display resolution detecting section acquires information on the resolution of the display device of the communication terminal device based on attribute information of the image data received from the communication terminal device. . 5. The communication management center according to claim 2, wherein the display resolution detecting section acquires information on a resolution of a display device of the communication terminal device based on a resolution of image data received from the communication terminal device. 6. The communication management center according to claim 2, wherein the display resolution detection unit acquires information on a resolution of a display device of the communication terminal device based on the type information received from the communication terminal device. 7. A communication management center to which a plurality of communication terminal devices are connected and which transmits / receives image data to / from each communication terminal device, and stores a plurality of image data transmitted from the communication terminal devices. Means, a display resolution detection unit for acquiring information about the resolution of the display device of the communication terminal device, and specified image data of the stored image data based on the information about the resolution acquired by the display resolution detection unit. And a transmitting unit that transmits the low-resolution image data obtained by the conversion in the resolution converting unit to a communication terminal device that specifies the resolution converting unit. Characteristic communication management center.