Music data distribution system and method, and storage medium storing program realizing such method

A music data distribution system for distributing music data to an external device connected to a network, comprises: a storage device that stores first music data; a receiver that receives a music data distribution request from the external device connected to the network, the music data distribution request comprising at least music data identification information and music data quality information; a reading device that reads the first music data from said storage device in accordance with the music data identification information; a quality converter that converts the first music data into second music data having a quality different from the first music data in accordance with the music data quality information; and a transmitter that transmits the first or the second music data to the external device in accordance with contents of the music data distribution request.

This application is based on Japanese Patent Application 2000-341899, filed on Nov. 9, 2000, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

A) Field of the Invention

The present invention relates to a music data distribution system, and more particularly to a music data distribution system for converting music data and distributing the converted music data to an external device via a network.

B) Description of the Related Art

There is a music data distribution system wherein music data of a musical instrument digital interface (MIDI) format, an MPEG Layer 3 (MP3) format or the like capable of being reproduced by electronic musical instruments, computers and the like can be purchased by downloading from a server via a network such as the Internet, instead of purchasing music data recorded in a recording medium such as a CD-ROM at stores.

In such a data distribution system, the music data is likely to be prepared in only one quality. Therefore, a user who just needs a low quality data sometimes needs to buy a high quality data for an expensive price.

The quality of music data includes not only the sound quality of reproduced music, but also the amount of information contained in the music data. The information contained in the music data includes score data corresponding to the music data, data for controlling a tone generator, and the like. In this specification, music data containing a larger amount of information is called music data of a high quality or high quality music data.

Music data is often sold separately for mobile phones and electronic musical instruments. Generally, music data for mobile phones and electronic musical instruments is recorded in different file formats, so that one cannot reproduce music data for another.

Therefore, the user should purchase music data that can be reproduced by an apparatus owned by the user. The user is required to search reproducible music data from a large amount of music data. It is also necessary for each user apparatus to access in a manner specific to the apparatus a home page selling reproducible music data.

If music data of various file formats and qualities compatible with various types of apparatuses is to be sold at one home page, a number of files are required to be prepared for each music piece and the memory capacity of the server increases.

If the number of types (qualities and file formats) of music data to be dealt with one home page increases, it becomes more difficult to select reproducible music data by using an apparatus owned by a user, leaving a risk of diminishing purchase desire.

SUMMARY OF THE INVENTION

An object of the present invention is to provide a music data distribution system capable of generating music data corresponding to a plurality types of qualities and presenting them to users, by changing the contents or an amount of information of pre-stored music data.

Another object of the present invention is to provide a music data distribution system capable of distributing music data having a quality matching a user terminal type and reception environment, at a reasonable price.

According to one aspect of the present invention, there is provided a music data distribution system for distributing music data to an external device connected to a network, comprises: a storage device that stores first music data; a receiver that receives a music data distribution request from the external device connected to the network, the music data distribution request comprising at least music data identification information and music data quality information; a reading device that reads the first music data from said storage device in accordance with the music data identification information; a quality converter that converts the first music data into second music data having a quality different from the first music data in accordance with the music data quality information; and a transmitter that transmits the first or the second music data to the external device in accordance with contents of the music data distribution request.

According to another aspect of the invention, there is provided a A music data distribution system for distributing music data to an external device connected to a network, comprises: a storage device that stores first music data; a receiver that receives a music data distribution request from the external device connected to the network, the music data distribution request comprising at least music data identification information and device identification information; a searching device that searches the first music data from said storage device in accordance with the music data identification information; a quality determiner that determines a quality of said music data which can be reproduced by said external device; and a transmitter that transmits information displayed on a display of said external device for promoting purchase of said music data with the quality determined by said quality determiner to said external device.

It is possible to generate music data corresponding to a plurality type of qualities and presenting them users, by changing the contents of music data prepared beforehand.

It is also possible to distribute music data having a quality matching a user terminal type and reception environment, at a reasonable charge.

It is also possible to generate music data corresponding to file formats reproducible by a plurality type of apparatuses, by changing the file format of music data prepared beforehand.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1is a block diagram showing an example of the structure of a music data distribution system1according to an embodiment of the invention. This system1has a data distribution apparatus (management server)2and a user terminal4interconnected by a communication network3such as the Internet or communication lines. The user terminal4may be a data communication terminal4afor wired communications or a portable communication terminal (portable data terminal)4bfor wireless communications.

The data distribution apparatus2is, for example, a World Wide Web (WWW) server on the Internet constituted of a computer PC or the like, and stores a large amount of music data as will be later described. This data distribution apparatus2provides pay services for distributing stored music data to the user terminal4upon request from the user.

The user terminal4may be the data communication terminal4aor portable data terminal4b, and can be connected to the communication network3such as local area networks (LAN), the Internet, and telephone lines. The user terminal4is connected to the management server2via the communication network3to download desired music data from the management server2. If the portable data terminal4bis used, this terminal is connected to a wireless base station6via a wireless communication channel5, and the base station6is connected to the management server2via the communication network3.

The user terminal4as a client transmits a command (music data request information) for requesting to download music data or the like to the management server2via the communication network3. Upon reception of this music data request information, the management server2distributes the requested music data or the like to the user terminal via the communication network3. The user terminal4receives the music data or the like and stores it in an external storage unit16or a RAM13shown inFIG. 2to be described later, to thus complete the download of music data or the like.

As will be later detailed, when the music data is downloaded, the management server2can convert the file format of stored music data into the file format reproducible at the user terminal, and can change the contents or information amount (quality) of music data so as to satisfy user desire.

FIG. 2is a block diagram showing the specific hardware structure of a computer PC constituting the user terminal4or management server2. The structure of the computer PC will be described by taking as an example the computer PC used as the data communication terminal4a(user terminal4).

Connected to a bus11are a detector circuit17, a display circuit19, a RAM13, a ROM12, a CPU14, an external storage unit16, a communication interface25, an MIDI interface23, a timer15and a tone generator circuit21.

A user can enter necessary information such as a music program name and singer name to be downloaded, by using an operation unit (input means)18connected to the detector circuit17. For example, the operation unit18may be any unit capable of outputting a signal corresponding to a user input, such as a mouse, a keyboard for entering characters and the like, a keyboard for musical performance, a joy stick, and a switch. A plurality of operation units may be connected.

The display circuit19is connected to a display20and can display various informations on the display20.

The external storage unit16has an interface and is connected via the interface to the bus11. The external storage unit16may be a floppy disc drive (FDD), a hard disc drive (HDD), a magneto optical disc (MO) drive, a compact disc read-only memory (CD-ROM) drive, a digital versatile disc (DVD) drive or the like. The external storage unit16may store a plurality of music data sets, a program for realizing the functions of the embodiment, and the like.

RAM13has flags, registers, buffers and working areas for CPU14for storing music data such as MIDI performance data. ROM12can store various parameters, control programs, the program for realizing the embodiment functions, and other data. The programs and other data are not required to be stored duplicately in the external storage unit16. CPU14performs calculations or controls in accordance with the control programs stored in ROM12or external storage unit16.

The timer15connected to CPU14and the bus11supplies CPU14with a main clock signal, interrupt timing and the like.

Music data and the like are stored in the external storage unit16, RAM13or ROM12. Music data can be transferred to and from the external via the communication interface25.

The MIDI interface23is used for connection to other musical instruments, audio apparatuses, computers or the like, and can transmit/receive at least MIDI signals. The MIDI interface23is not limited only to a dedicated MIDI interface, but it may be other general interfaces such as RS-232C, universal serial bus (USB) and IEEE1394. In this case, data other than MIDI message data may be transmitted/received at the same time.

The electronic musical instrument24is an audio apparatus, musical instrument or the like connected to the MIDI interface23. The type of an electronic musical instrument is not limited only to a keyed instrument, but other types may also be used such as a stringed instrument, a wind instrument and a percussion instrument. The electronic musical apparatus is not limited only to an electronic musical instrument of the type that the components thereof such as a tone generator and an automatic performance apparatus are all built in one integrated body, but these components may be discrete and interconnected by communication devices such as MIDI and various networks. The tone generator circuit21generates tone signals in accordance with supplied MIDI signals or the like, and supplies the generated tone signals to a sound system22. The sound system22includes a D/A converter and speakers, and converts supplied digital tone signals into analog tone signals to produce sounds.

The tone generator circuit21may be of any type, such as a waveform memory type, an FM type, a physical model type, a harmonics synthesis type, a formant synthesis type, and an analog synthesizer type having a voltage controlled oscillator (VCO)+a voltage controlled filter (VCF)+a voltage controlled amplifier (VCA).

The tone generator circuit21is not limited only to those made of hardware, but may be realized by a digital signal processor (DSP) and a micro program, by a CPU and a software program, or by a sound card.

One tone generator circuit may be used time divisionally to form a plurality of sound producing channels, or a plurality of tone generator circuits may be used to form a plurality of sound producing channels by using one tone generator circuit per one sound producing channel.

The control programs, program realizing the embodiment functions and the like may be stored in a hard disc (HDD) of the external storage unit16. By reading the control programs and the like from the hard disc to RAM13, CPU14can perform operations similar to those when the control programs and the like are stored in ROM12. In this case, addition, version-up and the like of the control programs and the like can be made easy.

The control programs, program for realizing the embodiment functions and the like may be stored in a CD-ROM. The control programs, program for realizing the embodiment functions and the like can be copied from CD-ROM to the hard disc. In this case, addition, version-up and the like of the control programs and the like can be made easy.

The communication interface25is connectable to the communication network3such as a local area network (LAN), the Internet, and a telephone line. The server is connected via the communication network3to download the control programs, the program realizing the embodiment functions, and the like from the server into the external storage unit16such as HDD or RAM13.

If the computer PC is used as the portable data terminal4b, the MIDI interface23and external storage unit are not necessarily required. In this case, the communication interface25is required to be connectable to the communication channel by wireless communications. For example, the communication interface25can connect a wireless communication channel for mobile phones. The portable data terminal4bis not limited only to a mobile phone, but it may be any type capable of connecting the communication network3by wireless communications.

If the computer PC is used as the management server (data distribution apparatus)2, the tone generator circuit21and the like are not necessarily required. The hardware structure is generally similar to that of the user terminal4. In this case, a plurality of original music data MO sets are stored in the external storage unit16of the management server2, as shown in FIG.6A.

The original music data MO is the data for reproducing a music program, which data is generated and recorded in the file format reproducible by an electronic musical instrument. The original music data MO is the data having a plurality of parts and the highest quality. The data of the highest quality contains reproduction parts corresponding in number to the maximum number of parts (e.g., 128 parts) which parts can be reproduced by a high quality music reproducing apparatus, a fine pitch change by pitch-bend data, a tone color change by tone color number data, score data for displaying a detailed score of all parts, and the like. The data of the highest quality may further contain fine setting of tone color contents by parameter setting, a fine tempo change by tempo data, a code progress designation by a code sequence, a fine velocity (sound volume) by velocity data and the like.

In this embodiment, particular data is removed from the original music data MO of the highest quality for electronic musical instruments to thereby create music data MD of various qualities. The file format is converted into the file format reproducible by cellar phones or the like.

FIG. 3is a flow chart illustrating a process to be executed by CPU14of the management server2and user terminal4of the music data distribution system according to the embodiment of the invention. The left part shown inFIG. 3illustrates the process to be executed by CPU14of the user terminal4, and the right part illustrates the process to be executed by CPU14of the management server2. Broken line arrows show a flow of data or the like to be transferred between the user terminal and management server via the communication network3(FIG.1).

The process on the user terminal side to be executed by CPU14of the user terminal4shown in the left side ofFIG. 3will be described first.

At Step SA1the process on the user terminal side starts to thereafter advance to next Step SA2.

At Step SA2a user enters a uniform resource locator (URL) of the management server2to connect the user terminal to the management server2via the Internet (communication network)3and download a music data purchase home page display file from the management server2. As the music data purchase home page display file is downloaded, this home page containing a music program information input window such as shown inFIG. 4Ato be described later, is displayed on the display20(FIG.2). Thereafter, the flow advances to next Step SA3.

The music data purchase home page display file is, for example, an HTML format file that can be displayed by a usual Internet browser. This file displays the music program information input window such as shown in FIG.4A and prompts the user to enter music data request information RI (FIG. 5) necessary for selecting music data or the like. The details of the music program information input window shown inFIG. 4Awill be later given.

At Step SA3the music data request information RI entered by the user as well as terminal information TI specific to the terminal stored beforehand in ROM12or the external storage unit16of the user terminal, is transmitted to the management server2. Thereafter, the flow advances to next Step SA4.

The music data request information RI and terminal information TI are integrated as one data block as shown in FIG.5. The music data request information to be entered by the user contains the information for identifying music data desired to be downloaded, such as a music program name and a singer name of the music data. The terminal information TI is stored beforehand in ROM12or the external storage unit16of the user terminal4, and contains the information for identifying the product type of the user terminal4, such as the product type name specific to the user terminal4.

Although the terminal information TI is preferably stored in advance in ROM12or the external storage unit16of the user terminal4as described above, a user may enter it manually.

The music data request information RI is entered by using the music program information input window in the music data purchase home page displayed at Step SA2.

At Step SA4the user terminal receives music data related information transmitted from the management server2at Step SB9to be described later. In accordance with the received music data related information, a list of purchasable qualities (hereinafter called a quality list) of the music data requested at Step SA3is displayed on the display20. Thereafter, the flow advances to Step SA5. The displayed quality list is, for example, a list such as shown inFIG. 4Bor4C to be described later.

At Step SA5the user is prompted to determine music data (commodity) to be purchased by referring to the quality list displayed at Step SA4. As the user selects the commodity and input the commodity information, the commodity information is transmitted to the management server2to thereafter advance to next Step SA6.

At Step SA6a charging information input window such as shown inFIG. 4Dto be described later is displayed on the display20to prompt the user to enter necessary purchase information. As the charging information is entered, this information is transmitted to the management server2to thereafter advance to next Step SA7.

The necessary purchase information is the information containing at least charging information. In this embodiment, although the commodity is downloaded immediately thereafter, a storage medium storing the commodity may be mailed. In this case, the user is prompted to enter the charging information as well as the information on the commodity mailing method and the information on delivery such as a mailing date. A user may select one of the downloading and mailing or both may be selected.

If charging is performed by using a credit card, the charging information contains a credit card number, an expiration date, an owner name and the like. If charging is performed by bank transfer or post office transfer, the information contains an address to which a transfer sheet is mailed or an email address to which a transfer sheet is transmitted. If charging is performed by e-cash, the charging information contains e-cash user information.

At Step SA7the purchased music data is downloaded from the management server2. After the download, the flow advances to next Step SA8.

At Step SA8, the process on the user terminal side is terminated.

Next, the process on the management server side to be executed by CPU14of the management server2shown in the right side ofFIG. 3will be described.

At Step SB1the process on the management server side starts. Thereafter, the process advances to next Step SB2.

At Step SB2in response to a connection request from the user terminal, the music data purchase home page display file to be received at the user terminal4at Step SA2of the process on the user terminal side is transmitted to the Internet (communication network)3to thereafter advance to Step SB3.

At Step SB3the management server receives the music data request information RI and terminal information TI transmitted from the user terminal4at Step SA3of the process on the user terminal side, and it is checked from the music data request information RI whether the original music data MO corresponding to the music data requested by the user is stored in the external storage unit16(FIG.2). Thereafter, the flow advances to next Step SB4.

At Step SB4if the check result at Step SB3indicates that the original music data MO requested by the user is stored in the external storage unit16(FIG.2), then the flow advances to Step SB7indicated by a YES arrow. If the original music data MO requested by the user is not stored in the external storage unit16(FIG.2), the flow branches to next Step SB5indicated by a NO arrow.

At Step SB5the user terminal4is notified via the Internet (communication network)3of the effect that the music data requested by the user does not exist. Thereafter, the flow advances to next Step SB6.

At Step SB6the process on the management server side is reset to return to Step SB1and resume the management server process.

At Step SB7by referring to a correspondence table shown in FIG.6B and the terminal information TI received at Step SB3, the management server determines the file format and quality of music data MD reproducible at the user terminal4which requested for the music data. Thereafter, the flow advances to next Step SB8.

As shown inFIG. 6B, the correspondence table includes two types of tables for mobile phones and electronic musical instruments (tables are prepared for each reproducible apparatus and each file format). The correspondence table matching the user terminal is selected by referring to the terminal information TI. For example, if the user terminal is a mobile phone (as confirmed by the terminal information TI), the correspondence table matching the mobile phone is used. The correspondence table for the mobile phone stores reproducible qualities for each of portable terminal product types including “mobile phone AA01”, “mobile phone AB01”, . . . , “mobile phone ZZ99”. InFIG. 6B, a symbol “circle” indicates that music data of that quality can be reproduced, and a symbol “cross” indicates that the music data of that quality cannot be reproduced.

For example, the “mobile phone AB01” cannot reproduce music data of the high quality, but it can reproduce music data of the middle and low qualities. In accordance with such information, a list DL shown inFIG. 4Cis displayed.

Conversion of the file format is judged from whether the user terminal apparatus (product type) represented by the terminal information TI belongs to (is recorded in) in the table for the mobile phone or the table for the electronic musical instrument. For example, if the user terminal apparatus is recorded in the mobile phone table, the file format is converted into the file format reproducible at the mobile phone.

In this embodiment, the correspondence table is prepared for each reproducible file format. It is not necessarily required to prepare the correspondence table for each file format. However, in this case, it is necessary to record a reproducible file format for each product type.

At Step SB8a price for each quality, determined at Step SB7, of music data reproducible at the user terminal4which requested for the music data is determined. Thereafter, the flow advances to next Step SB9. In determining the price for each quality, a table storing the price for each quality may be used, or a base price may be set to calculate from the base price the price for each quality by using a predetermined calculation method. In this embodiment, the price for each quality is recorded in a conversion table shown inFIG. 6Cto be described later.

At Step SB9the music data related information is transmitted to the user terminal4via the Internet3to prompt the user to purchase music data. The music data related information contains the quality of music data purchasable by the user determined at Step SB7and the price for each quality of the music data set at Step SB8. The transmitted music data related information is displayed as the quality list window shown inFIG. 4Bor4C to be described later. Thereafter, the flow advances to next Step SB10.

At Step SB10in response to an input (at Step SA5) of commodity purchase information from the user terminal4, a file for displaying at the user terminal4a charging information input window such as shown inFIG. 4Dto be described later is transmitted to prompt the user to enter the charging information. Thereafter, the flow advances to Step SB11.

At Step SB11the management server receives the charging information transmitted from the user terminal4at Step SA6of the user terminal side process, and executes a charging process in accordance with the received charging information. Thereafter, the flow advances to next Step SB12.

At Step SB12in accordance with the information on the commodity determined at Step SA5of the user terminal side process and received at Step SB10from the user terminal4, the music data of the quality determined at Step SA5of the user terminal side process is created from the original music data MO stored in the external storage unit16(FIG.2), by referring to a conversion table shown in FIG.6C. Thereafter, the flow advances to Step SB13.

As shown inFIG. 6C, the conversion table includes two types of tables for mobile phones and for electronic musical instruments. Similar to the correspondence table, the table matching the user terminal is used. For example, the conversion table for the mobile phone records information on the quality of music data and a price for each quality of the high, middle and low qualities. The quality information includes the number of reproduction parts, presence/absence of pitch-bend data, presence/absence of tone color data, and presence/absence of score data. InFIG. 6C, a symbol “circle” indicates that the corresponding data is not removed, and a symbol “cross” indicates that the corresponding data is removed.

For example, if the original music data is converted into the music data of the middle quality for a mobile phone, the mobile phone conversion table shown inFIG. 6Cis used, and the number of reproduction parts is reduced to two channels, the pitch-bend data in the original music data is removed, and the store data is removed. The tone color data is the same as that in the original music data. The price is 120 Yen.

The conversion table may be a table not only for the mobile phone and electronic musical instrument, but also for other apparatuses capable of reproducing music data. The price for the music data may be stored in the correspondence table shown inFIG. 6Bor it may be stored in another table.

At Step SB13by referring to the correspondence table shown inFIG. 6B, the file format of the created music data is converted into the file format reproducible at the user terminal4. Thereafter, the flow advances to next Step SB14.

At Step SB14the music data MD purchased by the user and having the desired quality is transmitted to the user terminal4via the Internet3. The quality of the music data MD was changed at Step SB12, and the file format thereof was changed at Step SB13to the file format reproducible at the user terminal4. After the music data MD is transmitted, the flow advances to next Step SB15.

At Step SB15the management server process is reset to return to Step SB1.

FIGS. 4Ato4D show examples of various display windows used for purchasing music data.

FIG. 4Ashows an example of the music program information input window displayed in the music data purchase home page on the display20of the user terminal4. The home page was transmitted from the management server2to the user terminal4at Step SB2shown in FIG.3. The music program information input window is not necessarily required to be displayed in the music data purchase home page, but it may be displayed in another window.

As shown inFIG. 4A, in the music program information input window, a message MG1such as “designate music program” is displayed to prompt the user to enter the music data request information RI, and a music program name input field26afor inputting a music program name and a singer name input field26bfor inputting a singer name are disposed.

The music program information input window is further provided with an “OK” switch SW1for enabling the input data and a “CANCEL” switch SW2for disabling the input data. These switches SW1and SW2are operated with a cursor38. If the product type name or the like is to be entered from a user, a product type name input field or the like is provided.

A user enters a music program name in the music program name input field26aand if possible the singer name in the singer name input field26b, moves the cursor38to the “OK” switch SW1, and clicks the cursor38with the operation unit such as a mouse. In this manner, the music data request information RI and terminal information TI are transmitted to the management server2.

FIG. 4Bshows an example of the quality list displayed in the music data purchase home page at Steps SA4and SA5. The quality list was transmitted at Step SB9shown inFIG. 3from the management server2to the user terminal4. In the example shown inFIG. 4B, there are three types of purchasable qualities including the high, middle and low qualities of the music data requested at Step SA3. In this embodiment, although the quality list is displayed in the music data purchase home page instead of the music program information input window, it may be displayed in another window.

As shown inFIG. 4B, with the quality list, a message MG2such as “designate commodity” is displayed to prompt the user to select a commodity, the music program name and user terminal name are displayed for user confirmation, and a commodity list DL of commodities usable at the user terminal is displayed.

Radio buttons SW3ato SW3care also displayed on the left side of the purchasable qualities including the high, middle and low qualities. The quality list is further provided with an “OK” switch SW1for enabling the input data and a “CANCEL” switch SW2for disabling the input data. These switches SW1and SW2and radio buttons SW3ato SW3care operated with a cursor38.

As a user clicks one of the radio buttons SW3ato SW3cand the “OK” switch SW1with the operation unit such as a mouse, the commodity is determined.

The display example shown inFIG. 4Bis used if the user terminal is of a high performance. In this case, the information of all the qualities from the high quality to low quality is displayed to allow the user to purchase music data of any one of the high to low qualities. If the user terminal is of a middle performance, the terminal can reproduce music data of only the middle and low qualities so that as shown inFIG. 4C, a list DL without the information for the high quality is displayed. The other displayed items are common to those shown in FIG.4B. If the user terminal can reproduce music data of only one quality, a list DL with the information only for that quality is displayed. Also in this case, the other displayed items are common to those shown in FIG.4B.

FIG. 4Dshows an example of the charging information input window displayed in the music data purchase home page at Steps SA6. The charging information input window was transmitted at Step SB10shown inFIG. 3from the management server2to the user terminal4. The charging information input window is not necessarily required to be displayed in the music data purchase home page, but it may be displayed in another window.

As shown inFIG. 4D, in the charging information input window, a message MG3such as “enter charging information” is displayed to prompt the user to enter charging information, and a charging information input field26cis displayed for entering charging information. The music program name, quality and price are also displayed for user confirmation. The charging information input window is further provided with an “OK” switch SW1for enabling the input data and a “CANCEL” switch SW2for disabling the input data. These switches SW1and SW2are operated with a cursor38.

As a user enters necessary charging information in the charging information input field26cand clicks the “OK: switch SW1with the operation unit such as a mouse, the charging information is transmitted to the managing server2.

FIG. 7is a block diagram showing the main functions of the music data distribution system1having the management server2, network3and user terminal4.

The management server2has at least: a music data storage unit32for storing the original music data MO; a music data request reception unit33for receiving music data request information from the user terminal4; a charging unit34for charging a user; a transmission unit35for transmitting the music data MD to the user terminal4via the network3; and a music data conversion unit36for converting the original music data MO into the music data MD in accordance with the music data request information of the user or the product type of the user terminal4.

The user terminal4has at least: an input unit26for inputting user request and designation, various information necessary for downloading the music data MD, and the like; a terminal information storage unit27for storing terminal information to used by the management server2to identify the product type or the like of the user terminal4; a music data request unit28for transmitting the music data request information RI and terminal information TI; a purchase setting unit29for transmitting and receiving information necessary for the charging process; a reception unit30for receiving the music data MD from the management server2via the network3; and a music data storage unit31for storing the music data MD received at the reception unit30.

A user inputs the music data request information RI from the input unit26of the user terminal4. The music data request information input from the input unit26is sent to the music data request unit28. The music data request unit28reads the terminal information TI specific to the terminal stored beforehand in the terminal information storage unit27, and transmits it together with the input music data request information RI to the management server2via the network3.

On the management server2side, the music data request reception unit33receives the transmitted music data request information RI and terminal information TI. By referring to the music data request information RI, the music data request reception unit33checks whether the original music data MO corresponding to the music data request information RI is stored in the music data storage unit32. If the original music data MO corresponding to the music data request information RI is not stored, this effect is notified to the user terminal4.

If the original music data MO corresponding to the music data request information RI is stored, the music data request reception unit33determines the quality reproducible at the user terminal4by referring to the terminal information TI and the correspondence table shown inFIG. 6B, and determines the music data reproducible at the user terminal4and its price by referring to the price for each quality recorded in the conversion table shown inFIG. 6Cor the like. The determined quality and price are sent to the charging unit.

In accordance with an instruction and information supplied from the music data request reception unit33, the charging unit34transmits the list DL (FIG. 4C) of qualities and prices of the music data to the user terminal4and prompts the user to purchase music data.

The purchase setting unit of the user terminal4receives the list DL of qualities and prices of the music data and displays it on the display20(FIG.2). By referring to the list DL, the user selects the commodity by operating upon the input unit26. The input unit26sends the information of the commodity selected by the user to the purchase setting unit29. The purchase setting unit29transmits the information on the quality of the purchased music data to the charging unit34via the network3.

Upon reception of the information on the quality of the purchased music data from the purchase setting unit29, the charging unit34prompts the purchase setting unit29to transmit the charging information, and instructs the music data conversion unit36to prepare the music data MD. At this time, information on the original music data MO to be converted, the file format to be converted of the music data MD, the quality and the like are also transmitted to the music data conversion unit36.

In response to the instruction from the charging unit34, the music data conversion unit36reads the original music data MO from the music data storage unit32. The read original music data MO is converted by using the conversion table shown inFIG. 6Cto make the music data MD have the quality requested by the user, and by using the correspondence table shown inFIG. 6Bto make the music data have the file format reproducible at the user terminal4(the file format matching the user terminal environment). The music data MD converted by the music data conversion unit36is sent to the transmission unit35.

The music data conversion unit33may be replaced by a music data selection unit. The music data selection unit selectively reads the requested music data reproducible at the user terminal from the music data storage unit32. In this case, the music data storage unit32stores music data being reproducible at a plurality type of user terminals and corresponding to a plurality type of qualities, for each of a plurality of music programs.

The purchase setting unit29prompted to transmit the charging information by the charging unit34prompts the user to enter the charging information. The user enters the charging information. The input charging information is transmitted to the charging unit34via the network3.

In accordance with the received charging information, the charging unit34performs a process necessary for charging, and instructs the transmission unit35to transmit the music data MD to the user terminal4.

Upon reception of the instruction from the charging unit34, the transmission unit35transmits the music data MD to the user terminal4via the network3.

The reception unit30of the user terminal4receives the music data MD and sequentially stores it in the music data storage unit31.

As described above, according to the embodiment of the invention, it is possible to distribute music data recorded by one file format by converting the file format into file formats (e.g., for electronic musical instruments and mobile phones) reproducible at various apparatuses.

Further, according to the embodiment of the invention, irrespective of the product type of the apparatus owned by a user, such as an electronic musical instrument and a mobile phone, proper music data can be purchased with ease.

Still further, according to the embodiment of the invention, music data converted into various qualities (music data having various data amounts) can be distributed.

Furthermore, according to the embodiment of the invention, a user can purchase music data of a desired quality at a reasonable price.

In the embodiment, a user selects one of qualities prepared beforehand for music data. Instead, the music data distribution system may be structured so that a user can select freely the detailed contents of each quality. For example, the detailed contents may be selected to the degree that the user terminal can deal with them (can reproduce the music data with the altered quality contents). In this case, charging is performed in accordance with the altered quality contents.

In this manner, a user can purchase music data having a finer quality desired by the user.

In this embodiment, although the quality of music data is changed depending upon presence/absence of particular musical performance data, the quality of music data may be changed by altering the contents of particular musical performance data.

FIG. 8shows an example of the conversion table for an electronic musical instrument for converting the contents of particular musical performance data. As shown inFIG. 8, the table records the detailed contents of particular musical performance data for each quality of music data to be converted.

For example, when the original music data MO is converted into the music data MD of the middle quality, although a resolution of sound producing timings is restricted, the original music data MO is converted into the music data having rhythmical sense. For the low quality, the original music data is converted into the music data without rhythmical sense through quantization.

As to the length of a music program, when the original music data MO is converted into the music data MD of the middle quality, an introduction, an interlude, and an ending are shortened, and for the low quality, the original data MO is shortened only to one chorus or to a motif part (main theme of the music).

In this manner, as the quality is lowered, the amount of musical performance data is reduced. Namely, the music data of the low quality has the musical performance data less than that of the music data of the high quality, so that a time taken to download the music data can be shortened.

In the above embodiment, although three qualities and three prices are set for the music data, the number of qualities and prices may be set as desired. For example, four or more qualities may be set and corresponding prices are set finely.

In the embodiment, the original music data MO of the high quality is prepared and the musical performance data amount is reduced to change the quality. Instead, music data of a low quality or middle quality may be used as the original music data MO and some musical performance data is added to improve the quality and create musical data of a higher quality. In this manner, the capacity of the external storage unit of the management server2can be reduced.

An audition function of allowing a user to audition a music program of each quality before purchasing it may be provided. Since the user can check the contents and quality of music data desired to purchase, the proper quality can be selected more easily.

In this case, Steps SB12and SB13are performed between Steps SB9and SB10to convert the quality and file format of requested music data and allow the user to audition the music program. It is not necessary to convert all of the music data for audition, but only a portion thereof may be converted.

Also in the embodiment, although a computer or portable data terminal is used as the user terminal (information communication terminal), other apparatus may also be used so long as they have an automatic performance function and a display. For example, an electronic musical instrument with a keyboard, a mobile phone with a tone generator, a karaoke apparatus, a game apparatus, an automatic performance piano or the like may also be used. The type of an electronic musical instrument is not limited only to a keyed musical instrument, but other types may also be used such as a stringed instrument, a wind instrument and a percussion instrument. The electronic musical apparatus is not limited only to an electronic musical instrument of the type that the components thereof such as a tone generator and an automatic performance apparatus are all built in one integrated body, but these components may be discrete and interconnected by communication devices such as MIDI and various networks.

The embodiment may be realized by a commercially available general computer installed with the computer program and the like realizing the functions of the embodiment.

In such a case, the computer program and the like realizing the embodiment functions may be stored in a computer readable storage medium such as a CD-ROM and a floppy disc and supplied to users.

If a general purpose computer or personal computer is connected to a communication network such as a LAN, the Internet and a telephone line, the computer program and various data may be supplied to the general purpose computer or personal computer via the communication network.

The present invention has been described in connection with the preferred embodiments. The invention is not limited only to the above embodiments. It is apparent that various modifications, improvements, combinations, and the like can be made by those skilled in the art.