JPH10243373A - Communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress increase in the storage capacity of communication terminal equipment caused by the distribution of image data from center equipment to communication terminal equipment. SOLUTION: The center equipment 1 stores plural kinds of image information to be distributed to communication terminal equipment 2 into a storage device 13 as image data encoded for plural data classes concerning respective data amounts and distributes the image data of data class requested from the communication terminal equipment 2. The communication terminal equipment 2 determines the data class of image data to be requested to the center equipment 1 based on the summed-up result of request frequency for a piece of music through a system control part 25, transmits a data transfer start request message containing that data class to the center equipment 1, receives image data distributed from the center equipment 1, stores them in a storage device 26, decodes these image data through an image decoding part 27 together with the reproduction of music and displays them on a monitor 24.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a PSTN, IS
Communication lines using communication cables such as DN, wireless communication,
The present invention relates to a communication system that exchanges various data via a communication line that does not use a communication cable such as satellite communication.

[0002]

2. Description of the Related Art In recent years, PSTN and ISD have been developed from center equipment.
2. Description of the Related Art A communication system that distributes various data to a plurality of communication terminal devices via a communication line such as N and uses the data on each communication terminal device side is often used.

For example, in a communication karaoke system, karaoke data (MIDI data, lyrics data, control data) is stored in a center device and communicated to the communication terminal device when a new song is registered or in response to a request from the communication terminal device. Distribute karaoke data via the line.

On the other hand, the communication terminal device stores the karaoke data received from the center device in a storage device such as a hard disk device (HD) built in or externally connected to the communication terminal device,
The music based on the karaoke data stored in the storage device is reproduced in response to a request from the user.

When reproducing karaoke data, the communication terminal device, based on image designation information included in the control data of the karaoke data, stores background image data previously stored in a storage device built in the communication terminal device, or Background image data recorded on a disk medium such as a CD or an LD is reproduced according to the music by an externally connected image storage / reproduction device.

However, in general, image data has a much larger capacity than music data. If the communication terminal device stores background image data for each piece of music, a large-capacity storage device must be provided. However, there has been a problem that the cost of the device increases and the size of the device increases.

[0007] To cope with this problem, there has been a technique in which a single background image data is shared and used by a plurality of music or a combination of background image data to be reproduced for each music is changed. Will be displayed,
In particular, if the same background image is displayed with different music, there is a problem that the change in the image is poor, the background image suitable for the tune is not displayed, and the user becomes tired or feels strange and cannot enjoy it sufficiently. .

Conventionally, a communication system in which background image data is stored in a center device and background image data corresponding to each music data is also delivered to a communication terminal device (for example, Japanese Patent Application Laid-Open No. 3-241567, Kaihei 5-1535
No. 86).

[0009]

However, in the above-mentioned communication system in which image data is also distributed from the center device to the communication terminal device, image data corresponding to all music received from the center device on a one-to-one basis is provided to the communication terminal device. A large-capacity storage device so that the image data can be stored, and an image storage / playback device for storing image data in a writable disk medium such as a CD-R must be connected. There is a problem that the size of the device increases and the size of the device increases.

[0010] The present invention has been made in view of the above points, and an object thereof is to suppress an increase in the storage capacity of a communication terminal device caused by distributing image data from a center device to the communication terminal device. And

In the communication system as described above, the communication terminal device calls the center device based on a request from a user, requests the center device to transmit designated karaoke data, and transmits the karaoke data. Terminal calling type distribution and center calling type distribution in which a center device calls a communication terminal device when a new song is registered or data is updated, and karaoke data is transmitted to each communication terminal device and stored. Yes. Even in the center calling type distribution, if there is no karaoke data corresponding to the request from the user, the distribution is received from the center device based on the terminal calling type distribution.

However, when the background image data is also received and reproduced from the center device in response to a request from the user, the communication time until the reception is completed is long because the image data is large-capacity data. There was a problem that it took a long time from the user's request to the reproduction, which was inconvenient.

It is another object of the present invention to enable a communication terminal device to receive and reproduce image data from a center device in a short time.

[0014]

In order to achieve the above object, the present invention is a communication system in which a center device and a terminal device are communicably connected via a communication line. Image data storage means for storing image information of each of a plurality of data types with respect to the data amount, and image data requested by the terminal device from the image data stored in the means. Image data transmitting means for reading out and transmitting image data corresponding to the type and the data type; providing the terminal device with a request frequency totalizing means for totalizing a request frequency from a user; Data type determining means for determining the type of image information and the data type required for the center device, and the type and data of the image information determined by the means. Image data requesting means for requesting image data of the data type to the center device, image data receiving means for receiving image data transmitted from the center device based on the request by the means, and image data received by the means , Image data decoding means for decoding image data stored in the means, and image information display means for displaying image information decoded by the means. .

The data type may be a data type classified based on a still image and a moving image. Further, the data type may be a data type classified based on a frame rate of a moving image. Further, the data type may be a data type classified based on image resolution. Further, the data type may be a data type classified based on image quality.

The image data storage means of the center device may be a device for storing a plurality of types of image information in the form of image data hierarchically encoded into a plurality of data types with respect to data amounts, respectively. The decoding means may be a means for decoding the hierarchically encoded image data.

Further, when the terminal device receives hierarchically higher layer image data from the center device, the terminal device reproduces the lower layer image data stored in the image data storage means in parallel with the reception. It is preferable to provide means for shifting to the reproduction of the image data upon completion of the reception of the image data of the upper layer.

[0018] In the communication system according to the first aspect of the present invention, the terminal device counts the request frequency from the user, and determines the type of image information and the data type to be requested of the center device based on the count result. The image data of the determined image information type and data type is requested to the center device via a communication line such as ISDN, PSTN, wireless communication, and satellite communication.

On the other hand, the center device accumulates a plurality of types of image information in the form of image data encoded in a plurality of data types with respect to the data amount, and corresponds to the type of image information and the data type requested by the terminal device. Read and transmit image data. Then, the terminal device receives the image data transmitted from the center device, stores the received image data, decodes the stored image data, and displays the decoded image information.

Therefore, a high-quality image to which a large amount of data is allocated to a terminal device with a high request frequency, and a low-quality image to which a low data amount is allocated to a terminal device with a low request frequency. Each can be provided, the data amount for storing the image data distributed from the center device can be reduced without significantly impairing the substantial function of providing the image to the user, and the storage capacity can be reduced. Increase can be suppressed.

In the communication system according to a second aspect of the present invention, data types are classified based on still images and moving images. A moving image to which a large amount is assigned can be provided, and a still image to which a small amount of data is assigned can be provided to those having a low request frequency.

[0022] Therefore, by providing a moving image with a variety of images to those frequently requested by the user, and by reducing the amount of data by a still image to those having a low request frequency,
It is possible to reduce the amount of data when storing image data distributed from the center device without significantly impairing the substantial function of providing images to the user, and to suppress an increase in storage capacity. it can.

In the communication system according to the third aspect of the present invention, the data type is classified based on the frame rate of the moving image. Can be provided for a moving image with a high frame rate to which a large amount of data is allocated, and a moving image with a low frame rate to which a small amount of data is allocated for a device with a low request frequency.

Therefore, a high-frame-rate moving image provides a high-quality video with a variety of changes to those frequently requested by the user, and a low-frame-rate moving image to provide a low-rate moving image to a low-frequency requested moving image. Reduces the amount of data when storing image data distributed from the center device without significantly impairing the substantial function of providing images to the user, and reduces storage capacity. The increase can be suppressed.

In the communication system according to the fourth aspect of the present invention, since the data type is classified based on the image resolution, a large amount of data is allocated to the terminal device that frequently requests the user. It is possible to provide a high-resolution image and a low-resolution image in which a lesser amount of data is allocated to a less frequently requested image.

Accordingly, by providing high-quality images with high-resolution images to those frequently requested by the user, and reducing the data amount by using low-resolution images to those requested less frequently, It is possible to reduce the amount of data when storing the image data distributed from the center device without significantly impairing the substantial function of providing the image to the server, and to suppress an increase in storage capacity.

Further, in the communication system according to the fifth aspect of the present invention, since the data type is classified based on the image quality, a large amount of data is allocated to the terminal device which is frequently requested by the user. By transmitting images with low quantization noise, high-quality images with little image degradation due to irreversible encoding during playback are provided. By transmitting an image with a small amount allocated, it is possible to save storage space.

In the communication system according to a sixth aspect of the present invention, the center device accumulates a plurality of types of image information as image data hierarchically encoded into a plurality of data types with respect to the data amount, respectively, and Since the encoded image data is decoded, the terminal device stores the image data of the low-quality data type in the terminal device, and transmits the image data of the high-quality data type of the same image information from the center device to the terminal device. When transferring, only the difference information is transmitted, and a high-definition image can be reproduced based on the difference information and the low-definition data type image data. The time can be reduced, and the terminal device can receive and reproduce the image data from the center device in a short time.

Further, in the communication system according to the present invention, when the terminal device receives image data of a hierarchically higher layer from the center device, the terminal device stores the image data in the lower layer in parallel with the reception. During the transmission of the image data, the image of the low-quality data type is reproduced by the reproduction of the image data, and the reproduction of the image data is performed upon completion of the reception of the image data of the upper layer. Image playback can be started quickly.

[0030]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a communication system according to an embodiment of the present invention. In this communication system, a center device 1 and a plurality of communication terminal devices 2 are connected so as to be able to perform data communication via an ISDN communication network (NETWORK) 3, and music and background images are transmitted from the center device 1 to each communication terminal device 2. Distribute data.

The center device 1 is composed of a center device main body 10 and a console terminal device 11 connected so as to be able to perform data communication via a communication cable, and includes a system control unit 12, a storage device 13, a plurality of ISDN interface units 14, And a functional unit such as a console interface unit 15.

The system control unit 12 includes a CPU, a ROM,
This is a microcomputer including a RAM, a timer, and the like, and controls the entire center device 1. Storage device 13
Is a memory such as a hard disk device, an optical disk device, or a magnetic disk device that stores various programs, tables, and data such as image data.

The ISDN interface unit 14 is composed of a network termination circuit, a communication controller and the like, and performs signal processing of the ISDN layer 1 and signal processing of the D channel layer 2. The console interface unit 15 is made of SIO or the like, and includes a console terminal device 11 and a system control unit 12.
Interface control of data transfer between the two.

The console terminal device 11 includes a CPU, an RO,
A main body containing a microcomputer comprising M, RAM, timer, etc., a display, a keyboard, a CD
It has a reading device and the like, and registers various data in the center device main body 10 and monitors the operation status of the center device main body 10.

On the other hand, the communication terminal device 2 has a remote controller 21 in which a microphone 22, a speaker 23, and a monitor 24 are connected to the communication terminal device main body 20. The communication terminal device body 20 includes a system control unit 25, a storage device 26,
Image decoding unit 27, graphic generation unit 28, MIDI
It has functional units such as a reproduction unit 29, an ISDN interface unit 30, a user interface unit 31, an audio effector unit 32, and an image synthesis processing unit 33.

The remote controller 21 allows the user to operate the communication terminal 2
It inputs various operation information from a position away from the camera and outputs an infrared signal indicating the operation information. The microphone 22 inputs a user's voice. The speaker 23 outputs music and voice. The monitor 24 displays a background image, lyrics and the like.
It is a display such as a CD.

The system control unit 25 includes a CPU, a ROM,
A microcomputer including a RAM, a timer, and the like, controls the entire communication terminal device 2. Storage device 26
Is a memory such as a hard disk device, an optical disk device, or a magnetic disk device that stores various programs, tables, and data such as music / background image data.

The image decoding unit 27 includes a color space converter, D /
An A converter or the like decodes encoded image data and outputs an analog image signal (RGB) signal. The graphic generation unit 28 includes a graphic controller, a D / A converter (RAMDAC), and the like, generates a graphic image for displaying lyrics and changing the color of the lyrics, and outputs an analog image signal (RGB).

The MIDI playback unit 29 is provided with a MIDI sound source, D
A / A converter, etc., reproduces music based on MIDI data in the music data, and outputs an analog audio signal thereof. The ISDN interface unit 30 includes a network termination circuit, a communication controller, and the like, and performs ISDN layer 1 signal processing and D channel layer 2 signal processing. The user interface unit 31 includes an LCD display, a keypad, an infrared receiver, and the like, analyzes various input operations of the user, and displays various kinds of guidance to the user.

The audio effector 32 comprises an effector, an amplifier, etc., performs an audio effect process such as echo and key control on the audio signal input from the microphone 22, and synthesizes a music signal reproduced by the MIDI reproducing unit 29. Then, the signal is amplified and output to the speaker 23.

The image synthesizing section 33 comprises a super imposer, an NTSC encoder, etc.
And an image based on the video signal from the graphic generation unit 28 and output to the monitor 24.

That is, the communication system is a communication system in which a center device and a terminal device are connected so as to be able to perform data communication via a communication line, and the system control unit 12 and the storage device 13 of the center device 1 include a plurality of types. Corresponds to image data storage means for storing image information of each of a plurality of data types in terms of data amount.

The system control unit 12 and the ISDN
The interface unit 14 reads out image data corresponding to the type of image information and the data type requested from the terminal device from the image data stored in the image data storage unit and transmits the read image data. Fulfill.

Further, the system control unit 25 of the communication terminal device 2 includes a request frequency counting means for counting the request frequency from the user, and the type of image information requested to the center device based on the counting result by the means. It functions as a data type determining means for determining the data type.

The system control unit 25 and the ISDN interface unit 30 request image data of the type and the data type of the image information determined by the data type determining unit from the center device. It functions as image data receiving means for receiving image data transmitted from the center device based on the request. Further, the system control unit 25 and the storage device 26 function as an image data storage unit that stores the image data received by the image data receiving unit.

The system control unit 25 and the image decoding unit 27 fulfill the function of image data decoding means for decoding image data stored in the image data storage means. Further, the monitor 24, the system control unit 25, and the image synthesis processing unit 33 function as an image information display unit that displays image information decoded by the image data decoding unit.

Then, the data type classified based on the still image and the moving image, the data type classified based on the frame rate of the moving image, the data type classified based on the image resolution, and the image quality are classified based on the image quality. It has a data type classified by

The system controller 12 of the center device 1
The storage device 13 also functions as means for storing a plurality of types of image information as image data hierarchically encoded into a plurality of data types with respect to the data amount. Further, the system control unit 25 and the image decoding unit 27 of the communication terminal device 2
Functions as a means for decoding the hierarchically encoded image data.

The system control unit 2 of the communication terminal device 2
5 reproduces the image data of the lower layer stored in the image data storage means in parallel with the reception of the image data of the upper layer hierarchically from the center device, and completes the reception of the image data of the upper layer. At the same time, it also functions as means for shifting to reproduction of the image data.

FIG. 2 shows a case where the communication terminal 2 is connected to the center 1.
FIG. 4 is a diagram showing an example of the structure of music / background image data distributed to a user. The music / background image data includes a music number 101 of the music to be reproduced, music information 102 on the music such as a music title, a composer, a lyricist, etc., a font size and font type for displaying lyrics and lyrics (for example, Mincho and Gothic)
Lyrics data area 103 for storing information on the
MIDI data, timing information for reproducing each piece of MIDI data, song data 104 such as lyrics color change and page break timing information, background image data 105 encoding background image information, and end of music / background image data A code EOF 106 is provided.

FIG. 3 is a diagram showing an example of the format of the request frequency management table of the communication terminal device 2. This request frequency management table is a management table for registering the requested music number of the music requested by the user in association with the requested date. The system controller 25 controls the remote controller 2 by the user.
The song number of the song input from No. 1 is registered as a requested song number, and the requested date is registered as a requested date in the request frequency management table. Then, based on the request frequency management table, the request frequency (request frequency) of the user for each music is totaled.

The request frequency management table may have a ring structure, and a storage capacity sufficient to manage a request history for a predetermined period (for example, the past month) with respect to the usage status (request frequency) may be allocated. . Further, in this embodiment, the request date is registered, but the request time may also be registered, and the request frequency based on the request date and the request time may be totaled.

FIG. 4 is a diagram showing an example of the format of the image data type determination table of the communication terminal device 2. This image data type determination table is a management table in which a data type number indicating the data type of the image data requested to the center apparatus 1 is registered for each number of requests (request frequency) of the user. Keep it. The figure shows an example of the image data content for each data type number.

Here, the classification of data types will be described. First, in the classification of a still image and a moving image, the encoding methods are different and the data amounts are different. For example, J
PEG (ISO / IEC10918-1), and MPEG2 (ISO / IEC13818-2) for moving images.
Still images can also be classified into JPEG (natural images) and GIF (graphics). In this case, the center device 1 determines image data having a different encoding method as the data type and transmits the data.

Further, classification is performed based on image quality due to image deterioration due to lossy encoding of images. For example, JPEG, M
In PEG2, classification is performed based on differences in image quality due to differences in the positions of coefficients to be quantized after DCT.

In this image data type determination table, data types "01" to "03" and data types "04" to
The classification “06” is a classification of a still image and a moving image. The classification of the data types “04” and “05” is the classification based on the frame rate of the moving image. Further, data types “02” and “03” and data types “05” and “0”
The category “6” is a classification based on image resolution. Furthermore, the classification of data types "01" and "02" is a classification based on image quality.

When a user requests a song, the system control unit 25 counts the number of requests for the requested song based on the request frequency management table, and refers to the image data type determination table to determine the number of requests. Is determined, and the data type number is determined as the data type of the image data requested to the center apparatus 1.

The content of the image data type determination table can be updated to the content transmitted from the center device 1. As described above, by updating the contents of the image data type determination table, the data type of the requested image data can be arbitrarily changed according to the number of requests.

FIG. 5 is a diagram showing an example of the format of the stored image data management table of the communication terminal device 2. The stored image data management table is a management table of the image data stored in the storage device 26, and registers a song number corresponding to the image data, a data type, and a file number indicating a storage destination. The system control unit 25 includes the center device 1
The storage image data management table is updated each time the storage device 26 stores the image data of the background distributed from.

FIG. 6 shows a case where the communication terminal device 2 is connected to the center device 1.
FIG. 6 is a diagram showing an example of a format of a data transfer start request message sent to the server. The data transfer start request message includes a message type indicating that it is a data transfer start request message for image data, a terminal number of a communication terminal device, a song number of a song requested (requested) by the user, and a request to the center device 1. Information such as a request data type indicating a data type to be performed and a data type of background image data requested from the center apparatus 1 is stored. In this case,
The song number corresponds to the type of the image data of the background.

Although not shown, the communication terminal device 2
Is a matrix for determining whether the data type of the image data stored in the storage device 26 at the time of a song request from the user matches the image data type determined based on the image data type determination table. It also has a shape determination table.

Further, the center device 1 stores image data of the various data types described above in the storage device 13. Both the center device 1 and the communication terminal device 2 use the image data of the background as other lyrics. Data and music data (data for music performance) are managed independently of each other, and the center device 1 distributes the data by linking based on a request from the communication terminal device 2 or distributes the data independently. Can be.

The system control unit 25 of the communication terminal device 2
When a user requests a song, it is determined whether or not the background image data of the requested song is stored in the storage device 26 based on the song number and the stored image data management table. When the background image data is not stored, a data transfer start request message is created based on the music number and the like, sent to the center device 1, and the center device 1 receives distribution of the background image data.

When stored in the storage device 26, the number of requests for the song having the song number requested by the user is totalized by referring to the request frequency management table, and the total number of requests is determined by referring to the image data type determination table. A request data type corresponding to the number of requests is determined. Furthermore, it is determined based on the determination table whether or not the data type of the image data stored in the storage device 26 matches the request data type determined based on the image data type determination table.

When they match, the storage device 26
Is played back, and if they do not match, the song number,
A data transfer start request message is created based on the request data type and the like, sent to the center device 1, and the center device 1 receives distribution of background image data.

The system control unit 25 requests the center device 1 to transfer the music / background image data by the data transfer start request message based on the result of the determination and the determination. When performance data is stored, it is possible to request transfer of only background image data. Further, when the image data of the lower layer is stored, it is possible to request to transfer only the difference data from the image data of the upper layer to the lower layer.

Next, the process of creating and registering music / background image data in the center device 1 will be described. The center device 1 creates music / background image data using an authoring tool (not shown). The authoring tool has a MIDI data input device, a lyrics data input device, a background image data input device, all functions of the communication terminal device, and a function of verifying each input data. And create music performance data.

The image data input device has a function as an image decoder, connects an existing video reproducing device such as a VTR, LD, film scanner, etc., and encodes a video signal input from the device. And creates background image data in which each of the background images is encoded into a plurality of data types with respect to the data amount.

The background image data is hierarchically coded so that a high-resolution / low-resolution or high-quality / low-quality (image quality) background image can be reproduced from the same coded data. Is used. For example, a progressive process of JPEG and SNR scalable of MPEG2 may be used for image quality, and a hierarchical process and spatial scalable may be used for resolution.

The music / background image data composed of the lyrics data, performance data, background image data, etc. created by the authoring tool is temporarily stored and accumulated in a data storage medium such as a CD, and managed by the center device 1. Is registered in the center device main body 10 based on the operation of the console terminal device 11 by the user.

The center apparatus main body 10 includes the system control unit 1
2 makes the music / background image data received via the console interface unit 15 a file, writes it in the storage device 13, and updates the contents of the music / background image data management table.

In this way, the storage device 13 stores background image information respectively corresponding to a plurality of music pieces as image data coded into a plurality of data types in terms of data amount. Since the music numbers correspond to the respective image data of the same background in the storage device 13, the music numbers perform the function of the type of image information. Therefore, the communication terminal device 2
Then, the type of the background image information is designated by the music number.

Next, distribution processing of music / background image data in this communication system will be described. FIG. 7 is a diagram showing a procedure for distributing music / background image data in this communication system. In the communication terminal device 2, the system control unit 25 makes a call to the center device 1 via the ISDN communication network 3 by the ISDN interface unit 30 based on an operation from the user.

When the system control unit 12 receives a call from the communication terminal device 2 to one of the ISDN interface units 14, the center device 1 controls the ISDN interface unit 14 that has received the call to control the communication terminal device. Responds to device 2. When the system control unit 25 confirms the response of the center device 1, the communication terminal device 2
0 sends a data transfer start request message to the center device 1.

When the system control unit 12 receives the data transfer start request message from the communication terminal device 2, the center device 1 first refers to the terminal number in the data transfer start request message and stores it in the storage device 13. The terminal number is checked against the terminal number registered in the terminal management table to check whether the terminal number is registered. By checking the terminal number, it is checked whether the transmission source of the data transfer start request message is the communication terminal device of the data distribution destination.

When the system control unit 12 determines that the data is registered, the system control unit 12 reads the music number / background image data corresponding to the information of the music number, the requested data type, and the image data type of the data transfer start request message from the storage device 13, ISD
The N interface unit 14 transmits the terminal number to the communication terminal device 2.

Next, reproduction processing of music / background image data by the communication terminal device 2 will be described. The system control unit 25 extracts the lyrics data from the music / background image data, and expands the lyrics image to the graphic generation unit 28 while reading out the font data stored in the storage device 26 in advance.

The system control unit 25 extracts music data from the music / background image data, and measures the MID in the music data while timing based on the timing information of the music data.
The I data is transferred to the MIDI reproducing unit 29. Further, the graphic generation unit 28 is controlled based on the lyrics color change data in the music data to change the color of the lyrics image and to change the page for changing the contents of the lyrics. Then, the system control unit 25 extracts the background image data from the music / background image data, transfers the extracted image data to the image decoding unit 27, and reproduces the background image.

Next, in the communication terminal device 2,
The reproduction process of the background image will be described in more detail. FIG. 8 is a flowchart showing a music / background image reproduction process of the communication terminal device. The user operates the remote controller 21 to request a song. The operation content of the remote controller 21 is notified to the system control unit 25 via the user interface unit 31.

The system control unit 25 determines whether or not there is a request from the user (S1), and if so, writes the requested music number into the request frequency management table shown in FIG. Is updated (S2), the music number is determined from the notified operation content, and the music / background image data management table in the storage device 26 is read (S2).
3) It is determined whether or not the song is a new song based on whether or not the corresponding song / background image data exists in the storage device 26 (S).
4).

At the time of a new tune, the system control unit 25 creates a data transfer start request message requesting the tune / background image data of the tune and calls the center device 1 to call it.
Based on the procedure shown in (1), the music / background image data is transmitted from the center device 1 and stored (S12), and the contents of the music / background image data management table and the stored image data management table are updated (S13). Then, the music / background image is reproduced (S11).

For example, when a data transfer start request message of request data type “00” and image data type “01” is transmitted, the center device 1 sends music data (music performance data), lyrics data, and image data of background image. Music / background image data consisting of a still image (JPEG) / low resolution (320 × 240) / low quality (DCT coefficient up to 32nd) is quantized as shown in FIG. The image data is distributed.

If the song is not a new song, the system control unit 2
5 retrieves the request frequency management table and counts the number of requests for the same music number during the past month (S5), and based on the coefficient result, the program shown in FIG.
The image data type corresponding to the number of requests is determined with reference to the image data type determination table shown in (1) (S6).

Thereafter, the system control unit 25 reads the stored image data management table shown in FIG. 5 stored in the storage device 26, further reads the current data type (S7), and determines the current data type and the number of requests. Based on the matrix-type determination table with the data type based on the tabulation result, it was determined from the data type of the existing image data (image data stored in the storage device 26) for the song number and the tabulation result of the request frequency management table. It is determined whether or not the image data type matches (S8).

At this time, it is also determined whether or not the difference between the data types can be changed only by transmitting the difference information. For example, in the image data type determination table shown in FIG. 4, the existing data type is “01”, and the image data type determined from the counting result of the request frequency management table is “0”.
2 ”, difference information (DCT coefficient 64
It is determined that the change can be made by transmitting only the information excluding the data quantized up to the th and the data quantized up to the 32nd DCT coefficient).

When the existing data type is "03" and the image data type determined from the tally result of the request frequency management table is "04", they have different encoding systems (different between JPEG and MPEG). Therefore, it is determined that the change cannot be performed by transmitting only the difference information.

If the data types are the same, the system control unit 25 creates a data transfer start request message, calls the center device 1, and generates a music / music data based on the procedure shown in FIG.
Upon receiving the transmission of the background image data (which may be only image data), it is stored in the storage device 26 and updated (S
9), update the stored image data management table (S1)
0), the music / background image is reproduced (S11), and this process ends.

For example, when a data transfer start request message of request data type “01” and image data type “01” is transmitted, the center apparatus 1 sends a still image (JPEG) / low resolution (320 × 240) / low quality ( Image data obtained by quantizing the 32nd DCT coefficient is distributed.

When a data transfer start request message of request data type “02” and image data type “02” is transmitted, the center apparatus 1 sends a still image (JPEG) / low resolution (320 × 240) / high quality ( Difference information between image data quantized up to the 64th DCT coefficient and image data quantized up to the 32nd DCT coefficient is distributed.

In the above-described processing, the processing for immediately transmitting image data when the data type based on the result of counting the request frequency does not match the data type of the existing image data has been described. In order to avoid sending out, immediately play the existing image data,
At the same time, the image data may be received from the center device 1 and updated, and the update result may be reflected in the next request.

In the case of a center calling communication system in which the center device 1 periodically distributes new music / background image data to the communication terminal device 2, the center device 1 uses the communication terminal device 2 periodically. After confirming the frequency, the image data of different data types may be replaced.

Further, in the above-described processing, the data type of a new music piece is fixed to “01” in accordance with an instruction from the communication terminal device 2, but for each music piece based on the request frequency assumed in the communication terminal device 2. The center device 1 may select it appropriately.

In the above processing, the JPEG / MPE
Although the case of classifying according to the section of G2 has been described, it is preferable to use GIF format image data for computer graphics. Further, the case where the classification is performed based on the division based on the spatial resolution has been described, but the classification may be performed based on the gradient of each pixel (the number of bits allocated to each pixel).

Next, the reproduction process of another music / background image will be described. FIG. 9 is a flowchart showing the processing. The processes in S21 to S28, S34, and S35 correspond to the processes in S1 to S8, S12, and S13 shown in FIG. 8, respectively, and thus description thereof is omitted.

In this processing, when the communication terminal device 2 stores the image data of the lower layer of the background image of the music requested by the user, the center device 1 reproduces the image data of the lower layer and stores it in the upper layer image data. The distribution of the difference information to be changed is received.

The system control unit 25 determines that the data type of the existing image data corresponding to the music number does not match the data type determined by the request frequency management table and the image data type determination table, and can be changed only by transmitting the difference information. (S28), the reproduction of the background image of the lower layer (lower layer) is started based on the existing image data (S2).
9).

At the same time as the reproduction of the background image, the center device 1 is requested for the difference information of the image data of the upper layer of the background image being reproduced, and the difference information distributed from the center device 1 is received. 26 (S30), and the stored image data management table is updated (S31).

Further, the current reproduction position (P) of the image data being reproduced is read from the image decoding unit 27 (S3).
2), once reset the image decoding unit 27, merge the difference information of the image data received from the center device 1 and transfer it to the image decoding unit 27, and play the background image of the upper layer from the playback position (P) Is started (S33).

As described above, in this communication system, the center device 1 distributes image data of background images having different data amounts to the respective communication terminal devices 2 in accordance with the frequency of requests for music from users. High-quality background images (moving images, high-frame-rate moving images, high-resolution images, and images with low quantization noise) are displayed for songs that are frequently requested, while low-quality background images are displayed for songs that are requested less frequently. Background images (still images, low frame rate moving images, low-resolution images, images with a lot of quantization noise) can be displayed, greatly impairing the substantial function of displaying background images displayed during music performance. In addition, the cost of storing the image data in the storage device 26 can be reduced.

For a song whose request frequency from the user has increased, when the image data of the low-quality background image for the song is stored in the communication terminal device 2, the center device 1 transmits the high-quality image. Since only the difference information to be changed to the data is delivered, there is no need to cause a delay in the response of the reproduction start at the time of the music request due to the transmission of the image data.

Further, the center device 1 reproduces the image data of the low-quality background image of the music requested by the user.
Receiving the difference information to change to high-quality image data from
Since the display shifts to the display of a high-quality background image based on the received difference information, the performance and the display of the background image can be started quickly together with the request of the user's music, and the waiting time of the user can be reduced. Can be.

The communication system according to the present invention has a PST
The same can be achieved by using a communication line such as N or wireless communication. Further, the present invention can be similarly implemented by using communication such as near VOD using satellite communication.

[0103]

As described above, according to the communication system of the present invention, it is possible to suppress an increase in the storage capacity of the communication terminal device caused by distributing image data from the center device to the communication terminal device. . Further, the communication terminal device can receive and reproduce the image data from the center device in a short time.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a communication system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a structure of music / background image data distributed from a center device shown in FIG. 1 to a communication terminal device.

FIG. 3 is a diagram showing an example of a format of a request frequency management table of the communication terminal device shown in FIG.

FIG. 4 is a diagram illustrating an example of a format of an image data type determination table of the communication terminal device illustrated in FIG. 1;

FIG. 5 is a diagram illustrating an example of a format of a stored image data management table of the communication terminal device illustrated in FIG. 1;

FIG. 6 is a diagram showing an example of a format of a data transfer start request message transmitted from the communication terminal device shown in FIG. 1 to the center device.

FIG. 7 shows music / music in the communication system shown in FIG.
FIG. 7 is a diagram showing a procedure at the time of distribution of background image data.

FIG. 8 is a flowchart showing a music / background image reproduction process of the communication terminal device shown in FIG. 1;

9 is a flowchart showing another music / background image reproduction process of the communication terminal device shown in FIG. 1;

[Explanation of symbols]

 1: Center device 2: Communication terminal device 3: ISDN communication network 10: Center device main body 11: Console terminal device 12, 25: System control unit 13, 26: Storage device 14, 30: ISDN interface unit 15: Console interface Unit 20: Communication terminal device main body 21: Remote control 22: Microphone 23: Speaker 24: Monitor 27: Image decoding unit 28: Graphic generation unit 29: MIDI reproduction unit 31: User interface unit 32: Audio effector unit 33: Image synthesis Processing unit

Claims (7)

[Claims] 1. A communication system in which a center device and a terminal device are communicably connected via a communication line so that a plurality of types of image information are encoded into a plurality of data types with respect to a data amount. Image data storage means for storing the image data stored therein, and an image for reading and transmitting image data corresponding to the type and data type of the image information requested by the terminal device from the image data stored in the means. A data transmission unit, a request frequency totalizing unit for totalizing a request frequency from a user in the terminal device, and a type of image information and a data type to be requested of the center device are determined based on a totaling result by the unit. Means for determining the type of image information and image data of the type and data type determined by the means for requesting the center apparatus. Requesting means, image data receiving means for receiving image data transmitted from the center device based on a request by the means, image data storing means for storing image data received by the means, A communication system comprising: image data decoding means for decoding the decoded image data; and image information display means for displaying image information decoded by the means. 2. The communication system according to claim 1, wherein the data type is a data type classified based on a still image and a moving image. 3. The communication system according to claim 1, wherein the data type is a data type classified based on a frame rate of a moving image. 4. The communication system according to claim 1, wherein the data type is a data type classified based on image resolution. 5. The communication system according to claim 1, wherein the data type is a data type classified based on image quality. 6. The communication system according to claim 4, wherein the image data storage means of the center device hierarchically encodes a plurality of types of image information into a plurality of data types with respect to data amounts. A communication system, wherein the image data decoding unit of the terminal device is a unit that decodes hierarchically encoded image data. 7. The communication system according to claim 6, wherein when said terminal device receives image data of a hierarchically higher layer from said center device, said image data is stored in said image data storage means in parallel with said reception. A communication system, comprising: means for reproducing image data of a lower layer, and shifting to reproduction of the image data upon completion of reception of the image data of the upper layer.