JP2010191458A - Musical sound generating terminal and performance terminal of electronic musical instrument performance system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To automatically allocate a destination address from a musical sound generation terminal to a performance terminal. <P>SOLUTION: The musical sound generation terminal 1 creates musical sound data based on performance data which is received from the performance terminal 2 via a network 12, and transmits the musical sound data to the performance terminal 2 via the network 12. The performance terminal 2 transmits an address request to the network 12 using wide area address when starting. When the musical sound generation terminal 1 receives the wide area address as a destination, the musical sound generation terminal transmits an address to the network 12 to allocate the address to the performance terminal 2 which has transmitted the wide area address. The performance terminal 2 transmits the performance data to the network using the address which has been transmitted to the network in response to the address request, as a destination address. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electronic musical instrument performance system, and more particularly to a musical sound data generation terminal and a plurality of performance data generation terminals included in the electronic musical instrument performance system.

  A method of connecting a plurality of musical instruments using a MIDI cable is known. In MIDI, basically only one-to-one connection is considered, so when connecting a plurality of electronic musical instruments, a MIDI cable corresponding to the number of connections is required. Further, since the electronic musical instrument is provided with only a limited number of MIDI terminals, the number of connected electronic musical instruments cannot be increased so much. For example, since there are 16 MIDI channels, 17 or more electronic musical instruments cannot be connected to each other at the same time. Further, in the MIDI standard, the communication speed is determined so as to transfer performance information, and it is difficult to transfer at higher speed.

  On the other hand, Patent Document 1 proposes a system in which a plurality of electronic musical instrument stations, operation slave stations, sound source stations, and sequencer stations are connected to each other via a LAN as a system that solves the above-described connection problems by MIDI. Yes.

Japanese Patent Laid-Open No. 6-252928

  In a system in which a plurality of electronic musical instruments and the like are connected to each other via a LAN as in the prior art disclosed in Patent Document 1 described above, for example, an electronic musical instrument station generates musical sounds based on real-time performance data transmitted from an operation slave station. It is conceivable that the musical sound is generated by the sound source station based on the real-time performance data and the musical sound is generated by the electronic musical instrument.

  However, in the prior art, although it is possible to generate sound at the own terminal using the musical sound data generated at the other terminal, the performance terminal that has transmitted the performance data is transmitted in real time by the musical sound data generated at the other terminal based on the performance data. It was not possible to generate music. That is, the sound source was not shared between performance terminals.

  For example, when a plurality of electronic keyboard instruments are connected via a LAN at a school or a music classroom to give a lesson or an ensemble, these students need only to have a keyboard device as an operator. Can't hear his performance. In order for each student to monitor his / her performance sound, all students must have an electronic keyboard instrument with a sound source that generates musical tone data together with the keyboard device. There is also a desire to hear not only their own performance sounds but also ensemble sounds with other students. Therefore, a system is desired in which a large number of students can simultaneously perform lessons on electronic musical instruments using a performance terminal such as a simple keyboard device.

  An object of the present invention is to provide a musical sound generating terminal and a performance terminal included in an electronic musical instrument performance system that enables performance by a plurality of performers while eliminating the waste of providing duplicate sound sources in view of the above problems. And

  In order to solve the above problems and achieve the object, the present invention receives performance data from a performance terminal via a network, generates musical sound data based on the performance data, and transmits the musical sound data to the network. In the musical sound generating terminal that transmits to the performance terminal via, receiving means for receiving the destination address transmitted from the performance terminal, and whether the destination address received by the receiving means is a wide area address not indicating an individual transmission destination Detecting means for detecting the address, assigning means for assigning an address to a performance terminal that has transmitted the wide-area address detected by the detecting means, and sending means for sending the address assigned by the assigning means to the network. The first feature is that it is a musical sound generating terminal.

  Further, the present invention transmits performance data by a performer to a musical tone generation terminal via a network, and receives musical tone data generated at the musical tone generation terminal based on the performance data via the network. In the performance terminal that generates sound, when the performance terminal is started up, transmission means for transmitting an address request to the network using a wide-area address that does not individually indicate a transmission destination, and an address sent to the network in response to the address request There is a second feature in that the performance terminal includes a receiving unit that receives the performance data and a sending unit that sends the performance data to the network using the received address as a destination address.

  According to the present invention having the first and second features, in the electronic musical instrument performance system in which the performance terminal and the musical sound generating terminal are connected via a network, the performance terminal is started up when the performance terminal is started up. In response to the wide area communication, an address as a destination address can be automatically assigned from the musical sound generating terminal to the performance terminal.

It is a block diagram of the electronic musical instrument performance system which concerns on one Embodiment of this invention. It is a block diagram of the control part contained in the terminal of the system concerning one embodiment of the present invention. It is a figure which shows the structural example of an IP packet. It is a figure which shows the content of an IP header, and its meaning. It is a main flowchart of a musical tone generation terminal. It is a flowchart of an event process. It is a flowchart of a communication process. It is a flowchart of a timer process. It is a flowchart of initialization in a performance terminal. It is a flowchart of the event process in a performance terminal. It is a flowchart of a packet process. It is a flowchart of a key process. It is a flowchart of a packet transmission process. It is a figure which shows the principal part of the operation panel 4 of a musical tone generation terminal. It is a block diagram which shows the principal part function of an operation panel. It is a block diagram which shows the principal part function of the operation panel which concerns on a modification. It is a figure which shows the state of the switch on an operation panel. It is a block diagram which shows the principal part function of a non-delivery process. It is a flowchart which concerns on a cross fade process when a packet does not arrive by the sounding timing. It is a flowchart of the reception process of a packet. It is a flowchart of a pronunciation process. It is a flowchart of a return process.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of an electronic musical instrument performance system according to an embodiment of the present invention. In the figure, this performance system is, for example, an electronic musical instrument lesson system for a plurality of students. This performance system includes a musical sound data generation terminal (hereinafter referred to as “musical sound generation terminal”) 1 used by a teacher and a plurality of performance data generation terminals (hereinafter referred to as “performance terminals”) 2 used by students.

  The musical sound generating terminal 1 includes a keyboard 3, an operation panel 4, a sound source (TG) 5, a sound system 6, and a control unit 7. The keyboard 3 includes a key sensor (not shown) that detects key depression / release and outputs performance data (including key number and velocity) in real time according to the performance of the performer. The operation panel 4 has a display screen such as a switch for inputting various instructions and a liquid crystal panel. A plurality of sound sources 5 are provided and generate musical sound data based on performance data. The sound system 6 includes a D / A converter (DAC) 61 for music data, an amplifier (AMP) 62, and a speaker (SP) 63. A headphone terminal is provided so that the output of the amplifier 62 can be supplied not only to the speaker 63 but also to a headphone terminal (not shown).

  The performance terminal 2 includes a keyboard 8, an operation panel 9, a sound system 10, and a control unit 11. The performance terminal 2 is different from the tone generation terminal 1 in that it does not hold the sound source 5 and the waveform data and parameters used by the sound source 5. Further, the operation panel 4 of the musical tone generating terminal 1 is provided with a switch (described later) that is not provided on the operation panel 9 of the performance terminal 2. Note that the musical tone generating terminal 1 is not necessarily provided with the keyboard 3.

  The control units 7 and 11 of the tone generation terminal 1 and the performance terminal 2 are connected to the line 12. The line 12 is an IEEE 802.3 standard LAN, that is, Ethernet (registered trademark), and it is preferable to use a 100BASE-T specification having a transmission rate of 100 megabits / second. The following description will be made on the assumption that the line 12 is a LAN, but the present invention is not limited to a LAN. That is, it may be a wide area network (WAN) in which a plurality of separated classrooms are connected.

  Assuming that the sampling frequency of the musical sound waveform is 44.1 kHz, the sampling accuracy is 18 bits × 2 (considering stereo), the number of performance terminals n is 48, the amount of information S by transmitting musical sound data is 44100 × 18 × 2 × 48 = 76. , 204,800 (bits / second). Even if 30% overhead such as an address or header is estimated for this information amount S, the amount of data transmitted on the line 12 is 99,066,240 bits / second, which does not exceed the allowable capacity of the line 12 of 100BASE-T specifications. . Note that the amount of information transmitted by the performance data from the performance terminal 2 can be ignored in calculation because it is an order of magnitude smaller than the amount of information transmitted by the musical sound data.

  FIG. 2 is a block diagram showing the configuration of the control unit 7. The control unit 7 includes a CPU 13, a ROM 14, a RAM 15, a digital signal processor (DSP) 16, and an input / output interface (SIO) 17. The CPU 13, ROM 14, RAM 15, DSP 16 and SIO 17 are connected via a bus 18. The keyboard 13, the operation panel 4, and the sound source 5 are connected to the CPU 13, and the sound source 5 is connected to the DSP 16. The control unit 7 is connected to the line 12 through the SIO 17. The ROM 14 stores waveform data and parameters used by the sound source 5 in advance.

  The control unit 11 of the performance terminal 2 is also configured in the same manner as the control unit 7 except for the connection with the sound source 5 and the difference in data held in the ROM 14. The control units 7 and 11 transmit and receive data using the Internet protocol (IP).

  FIG. 3 is a diagram illustrating a structure example of an IP packet. The packet 19 includes an Ethernet (registered trademark) header, an IP header, a MIDI / PCM header, a MIDI / PCM body, and an Ethernet (registered trademark) trailer. The contents of the IP header and its role are shown in FIG.

  FIG. 5 is a flowchart showing the main routine of the musical tone generating terminal 1. In step S1, various registers, counters, flags, etc. are initialized. In step S2, the presence / absence of an event such as operation of the keyboard 3 (keyboard event) or operation of the operation panel 4 (panel event) is determined. The presence / absence of a panel event is determined by a monitoring operation of the state of switches and volumes provided in the operation panel 4. The presence / absence of a keyboard event is determined by an output monitoring operation of a key sensor provided for each key of the keyboard 3, and the presence / absence of key depression / release and the velocity are detected for each key. If any event is detected, processing corresponding to the event is executed in step S3. When the event processing is completed, timer processing is performed in step S4.

  FIG. 6 is a flowchart of event processing. In step S10, it is determined whether or not the event is a main body event, that is, an event that has occurred on the musical sound generating terminal 1 side or an event that has occurred on the performance terminal 2. If the event is a main body event, normal processing for sound generation is performed in step S11. For example, a process for sound generation or muting is performed depending on whether a keyboard event is pressed or released. Note that automatic accompaniment using scheduled accompaniment data may be performed along with normal pronunciation according to a keyboard event. If it is not a main body event, the process proceeds to step S12 to perform communication processing.

  FIG. 7 is a flowchart of the communication process. In step S20, it is determined whether or not the packet is addressed to the own station, that is, whether or not the destination address TADD of the packet is the address of the musical tone generating terminal 1. If it is addressed to the own station, the process proceeds to step S21 to extract MIDI data from the received packet. In step S22, musical tone data is created based on this MIDI data.

  If step S20 is negative (not the own station address), the process proceeds to step S23 to determine whether the communication is a wide area communication, that is, whether the musical sound generating terminal 1 is a communication from the performance terminal 2 to which the address is assigned or a communication from other than that To do. If it is not wide-area communication, this process is passed, and if it is wide-area communication, it is the time when each performance terminal is started up or a new performance terminal is generated, and the process proceeds to step S24 and an address is assigned to that performance terminal. In step S25, the address assigned in step S24 is sent to the line 12.

  FIG. 8 is a flowchart of the timer process. In step S30, it is determined whether or not there is musical tone data. If the musical sound data is created in step S22, this determination is affirmative, and the process proceeds to step S31 to create a packet for transmitting the musical sound data. In step S32, the created packet is sent to the line 12.

  Subsequently, processing of the performance terminal 2 will be described. Since the main flowchart of the performance terminal 2 is the same as that of the musical tone generating terminal 1, it will be omitted, and only specific processing of each step of the main flowchart will be described.

  FIG. 9 is a flowchart of initialization of the performance terminal 2. This initialization process is performed every time the performance terminal 2 is started up. In step S40, the packet buffer for storing the packet is cleared. In step S41, the musical tone generating terminal 1 is requested for an address. Step S24 is a process corresponding to this address request. In step S42, other parameters and the like are initialized.

  FIG. 10 is a flowchart of event processing in the performance terminal 2. In step S50, it is determined whether or not a packet is received. If a packet has been received, the process proceeds to step S51 to perform packet processing (described later).

  If a packet has not been received, the process proceeds to step S52 to determine whether it is a keyboard event. If it is a keyboard event, the process proceeds to step S53 to perform key processing (described later). If it is not a keyboard event, it will progress to step S54 and it will be judged whether it is a panel event. If it is a panel event, the process proceeds to step S55 to perform panel processing. In the panel processing, for example, control data such as timbre data and expression is created as control packet data and written to the packet buffer. If it is not a panel event, the process proceeds to step S56 to determine whether it is another event or not, and if it is another event, the other process scheduled in step S57 is performed.

  FIG. 11 is a flowchart of packet processing. In step S60, it is determined whether an address is received. If an address has been received, the process proceeds to step S61, where address processing for writing the received address in a predetermined storage area on the RAM 15 is performed. If the address is not received, the process proceeds from step S60 to step S62 to determine whether or not the musical sound data is received. If the musical sound data has been received, the process proceeds to step S63 to perform musical sound processing for generating a musical sound. In the musical tone processing, the packet is disassembled, PCM data is taken out from the MIDI / PCM body, and stored in the buffer of the RAM 15. The PCM data stored in this buffer is input to the speaker 63 via the D / A converter 61 and the amplifier 62 of the sound system 6 and is used for sound generation.

  FIG. 12 is a flowchart of key processing. In step S70, it is determined whether or not the key is depressed. If the key is depressed, the process proceeds to step S71 to generate key depression packet data. That is, the key number and velocity of the pressed key are stored in the packet buffer for writing into the data field of the packet. If the key is not depressed, the process proceeds to step S72 to determine whether or not the key is released. If the key is released, the process proceeds to step S73 and key release packet data is generated. The key release packet data is stored in the packet buffer in the same manner as the key depression packet data.

  FIG. 13 is a flowchart of packet transmission processing. This process is performed every scheduled interruption time as a timer process. In step S80, it is determined whether or not there is data in the packet buffer. If there is data in the packet buffer, the process proceeds to step S81 to create a packet. That is, a packet is completed by adding a header, a trailer, or the like to key-pressed packet data, key-released packet data, and control packet data. In step S82, this packet is sent to the line 12.

  Next, specific examples of lessons by the lesson system will be described. FIG. 14 is a diagram showing a main part of the operation panel 4 of the musical tone generating terminal 1 used by the teacher. The main part of the operation panel 4 is not provided on the operation panel 9 of the performance terminal 2 used by students. Here, a maximum of 24 students is assumed. However, the performance terminals 2 used by the students are not limited to being accommodated in a single classroom, but may be accommodated in a plurality of rooms. May be housed in a room. In short, it is only necessary that the performance terminal and the musical sound generating terminal 1 used by 24 students are connected to each other via a LAN or WAN line 12.

  The operation panel 4 includes a microphone (microphone) 20, a microphone switch 21, a monitor switch 22, an ensemble switch 23, and a self-performance switch 24. Each switch has 24 switches for the maximum number of students. Each of the switches 21 to 24 is preferably one that can be switched on and off and whose switching position can be recognized with the eyes. There are no restrictions on the type of push switch, toggle switch, touch switch, etc.

  The sound input from the microphone 20 is digitized and added to the musical sound data, and then transmitted to the performance terminal 2 of the student whose microphone switch 21 is turned on. The monitor switch 22 is for monitoring the sound generation by the performance data from the performance terminal 2 with the switch 22 turned on, and the teacher can listen to the performance through the speaker 63 and headphones (not shown).

  The ensemble switch 23 is provided so that the student can hear the ensemble sound of his / her performance and the performance of another student. The musical sound data formed at the musical sound generating terminal 1 by the performance data from the performance terminal 2 whose ensemble switch 23 is turned on are added together and transmitted to the performance terminal 2.

  The self-playing switch 24 is one in which only the performance data from the performance terminal 2 with the switch 24 turned on is validated and processed by the musical sound generating terminal 1, and from the performance terminal 2 with the switch 24 not turned on. The performance data of is ignored.

  According to the state of each switch in FIG. 14 (black circle is on, white circle is off), since all the microphone switches 21 are on, the teacher's voice reaches the performance terminals 2 of all students through the microphone 20. Since the ensemble switch 23 is turned on only for the performance terminals 2 and 4, the students of the performance terminals 2 and 4 can hear each other's performance as an ensemble. In addition, since all the performance terminals 2 are selected by the self-performance switch 24, students other than the students of the performance terminals 2 and 4 can listen only to their performance. Accordingly, when it is desired to evaluate the second and fourth ensembles, even if other students perform, the sound does not affect the second and fourth students. Further, since the monitor switch 22 selects only the second performance terminal 2, the teacher is monitoring only the second performance.

  FIG. 15 is a block diagram showing the main functions of the operation panel 4 shown in FIG. In FIG. 15, while an A / D converter 25 is provided and the microphone switch (SW 1) 21 is on, an input audio signal from the microphone 20 is digitally converted by the A / D converter 25 and input to the adder 26. Is done.

  Performance data from the performance terminal 2 selected by the self performance switch (SW4) 24 is input to the sound source 5 via the line 12. The sound source 5 generates musical tone data based on the performance data. The tone generator 5 outputs musical tone data based on the performance data of the performance terminal 2 whose monitor switch (SW2) 22 is turned on as the monitor signal Mout. Monitor signals Mout based on performance data from all performance terminals 2 for which the monitor switch (SW2) 22 is turned on are added and input to the D / A converter 61 of the sound system 6. This addition may be performed on the output side of the D / A converter 61.

  The musical sound data Eout generated by the sound source 5 is output to the synthesizing unit 26 via the ensemble switch (SW3) 23. The synthesizer 26 adds (preferably digitally) the musical tone data of the performance terminals 2 whose ensemble switch (SW3) 23 is turned on to output synthesized musical tone data Ein. The synthesized musical sound data Ein is added to the input audio signal from the digitally converted microphone 20 by the adder 26, packetized by the packet generator 28, and sent to the line 12 via the transfer unit 29.

  The output from the sound source 5 is always sent to the line 12 regardless of the state of the switch (SW2) 22 and the switch (SW3) 23. Therefore, in order to prevent this output from the sound source 5 from being added to the synthesized musical sound data Ein by the adder 27 and resulting in double addition, the musical sound data directly transmitted from the sound source 5 in advance via the subtractor 30 is excluded. I am doing so.

  The subtractor 30 is necessary because the adder 27 is provided to constantly send the output of the sound source 5 to the line 12, and the same function can be achieved without using the subtractor 30. For example, the output of the sound source 5 may be output with the reverse logic of the ensemble switch (SW3) 23, and the synthesized musical sound data Ein may be input to the adder 27 as it is (see FIG. 16). In FIG. 16, a switch SW3 ′ (switch 23a) is an inverse logic switch of the ensemble switch (SW3) 23.

  FIG. 17 is a diagram illustrating another state of the switches 21 to 24. According to the state of the switch in this figure, the ensemble switch 23 is turned on for all students, so that all students can receive and reproduce musical tone data. However, since the self-performance switch 24 is turned on only for the second and fourth students, the performance data is only valid for the performance terminals 2 of the second and fourth students. Therefore, only the performances of the students No. 2 and No. 4 are ensembled, and other students can listen to the ensemble sound. The function of the self-play switch 24 has the effect that even if a student other than No. 2 and No. 4 plays due to mischief or mistake, it is ignored and not reflected in the ensemble.

  The configuration of the switch on the operation panel 4 is not limited to the above embodiment. For example, the ensemble switch 23 may be omitted. Also, the ensemble switch 23 is omitted, and one ensemble and solo selection switch is provided so that the selection of the ensemble or solo can be selected. In this case, only the performance terminal selected as the ensemble terminal can hear the ensemble sound including its own performance.

  Next, a device for correcting a communication error in music data will be described. In packet communication performed using the Internet protocol, data may contain errors. In addition, packets may not arrive in the order of transmission (late arrival), or packets may not arrive (non-arrival).

  Therefore, in the present embodiment, the following countermeasures are taken against packet late arrival, non-arrival, and data error. First, when the packet does not arrive by the sound generation timing, it is regarded as non-arrival for both late arrival and non-arrival, and the packet is discarded even if it arrives after that timing. No packet retransmission is requested for non-delivery. Then, instead of the discarded packet, the previous packet is looped and sounded. The reason for not requesting retransmission is that the sound is interrupted if the packet is retransmitted in response to the retransmission request.

  In order to use the immediately preceding packet, first, as a premise, sound generation is always performed with a delay of one packet. Therefore, the previous packet has arrived when it is regarded as non-delivery, but sound generation has not yet been performed. If the packet does not arrive by the start of sound generation by the immediately preceding packet, the immediately preceding packet is sounded by self-looping and is sounded instead of the non-delivery packet. When the next packet arrives, the packet immediately before looping and the arrival packet are cross-faded and sounded.

  The process at the time of non-delivery is demonstrated with reference to a figure. FIG. 18 is a block diagram illustrating main functions of the non-delivery process. In this figure, for easy understanding, the packet and the musical sound data contained in the packet are treated as synonymous. The received packets are stored in the buffer 31 in the order of arrival, and the packets are decomposed in the order of arrival by the reading unit 32 and input to the D / A converter 61 for sound generation. The discriminating unit 33 discriminates whether or not the packet next to the packet used for the sound generation at the start of sound generation is non-delivery. When not arrived, the musical sound data is cross-faded by the first cross-fade unit 34 as the first calculating means, as will be described later, and replaced with a non-arrival packet. When the determination unit 33 determines that the subsequent packet has arrived at the start of sound generation based on the musical sound data calculated by the first crossfade unit 34, the second crossfade unit 35 crossfades the musical sound data as will be described later. Instead of the subsequent packet.

  In the example of FIG. 18, the preceding packet p [j-1], the current packet p [j], and the succeeding packet p [y] have arrived. The packets p [j + 1] and p [j + 2] that should arrive between the current packet p [j] and the subsequent packet p [y] have not arrived.

  Here, it is assumed that the current packet p [j] has started sound generation processing. The determination unit 33 determines whether or not the next packet p [j + 1] has arrived at the start of sound generation by the current packet p [j]. Here, when the packet p [j + 1] has not arrived, the first crossfade unit 34 crossfades the preceding packet p [j-1] and the current packet p [j] to obtain the packet p [x]. When the sound of the packet p [j] is finished, the packet p [x] obtained by crossfading is used in place of the musical sound data of the packet p [j + 1] to generate a musical sound.

  Then, it is determined whether or not the packet p [j + 2] has arrived at the start of sound generation by the packet p [x], and when it does not arrive, the packet p [x] is looped again. Further, at the start of this loop, it is determined whether or not the subsequent packet p [y] has arrived. Here, since the subsequent packet p [y] has arrived, the determination unit 33 causes the second crossfading unit 35 to crossfade the packet p [x] and the subsequent packet p [y] currently in the loop, and this cross The faded packet is used in place of the succeeding packet p [y] to generate sound. In this way, the musical sound data is cross-faded to create alternative musical sound data, thereby making the musical sound data that is not originally continuous have continuity.

  FIG. 19 is a flowchart related to the non-delivery process, that is, the crossfade process when the packet does not arrive by the sound generation timing. In step S90, "0" is set to the variable i indicating the sample number in the packet of musical sound data. The maximum number of samples, that is, the variable i is n. In step S91, the value a is set as the amplitude corresponding to the sample number i of the packet [j-1] immediately before the packet p [j] immediately before the non-arrival packet. In step S92, the amplitude a is multiplied by the value i / n of the ratio between the sample number i and the number of samples n (for example, “256”) to set a new amplitude a. In step S93, it is set as a value b indicating the amplitude corresponding to the sample number i of the immediately preceding packet [j]. In step S94, the complement “1-i / n” is multiplied by the amplitude b and set as a new amplitude b. In step S95, “a + b” is set as the amplitude of the sample number i of the crossfade packet p ′. To do. In step S96, the sample number i is updated (+1), and whether or not n samples have been processed is determined based on whether or not the value i is equal to the number of samples n. The process proceeds to step S91 until the sample number i is equal to the number of samples n. If the sample number i is equal to the number of samples n, the process proceeds to step S97, and the flag xfmode indicating the crossfade mode is set to “1”. . The initial value of the flag xfmode is “0”.

  FIG. 20 is a flowchart of reception processing when a packet is received. In step S100, it is determined whether or not the received packet is regarded as non-delivery and discarded. If it has been discarded, this flowchart is bypassed. In step S101, the flag xfmode is determined. If the flag xfmode is “0”, it is determined that the reception is normal, and the process proceeds to step S102 to determine whether there is a parity error. If a parity error has occurred, in step S103, an interpolation value is taken between samples immediately before and after the error sample, and the interpolation value is used in place of the error sample. Then, the process proceeds to step S104. The sample interpolation in step S103 is omitted when there is no parity error before and after the erroneous data. In step S104, the received packet is stored. When the flag xfmode is determined to be “1” in step S101, the process proceeds to step S105, and the received packet is transferred to the return processing unit for the return process.

  FIG. 21 is a flowchart of the sound generation process. In step S110, it is determined whether there is a packet to be sounded. If there is a packet, the process proceeds to step S111. In step S111, it is determined whether the next packet has arrived. If the next packet has also arrived, the process proceeds to step S112 to determine the flag xfmode. If the flag xfmode is “1”, the process proceeds to step S113, the next packet is restored, and the process proceeds to step S114. The musical tone data of the packet subjected to the restoration process is converted into a D / A converter 61 for sound generation. Forward to. If the flag xfmode is “0”, the return process of step S113 is skipped and the process proceeds to step S114, where the musical sound data of the first packet is transferred to the D / A converter 61 for sound generation.

  When the next packet has not arrived, the process proceeds from step S111 to step S115. In step S115, as a non-arrival event, the packet that has been crossfade in the non-delivery process is read. In step S114, the musical tone data of the packet read in step S115 is transferred to the D / A converter 61 for sound generation.

  FIG. 22 is a flowchart of the return process. In step S120, "0" is set to a variable i indicating the sample number in the musical sound data packet. The maximum number of samples, that is, the variable i is n. In step S121, the value a is set as the amplitude corresponding to the sample number i of the packet p [x] being looped. In step S122, the value i / n of the ratio between the sample number i and the number of samples n (for example, “256”) is multiplied by the amplitude a to set a new amplitude a. In step S123, a value b indicating the amplitude corresponding to the sample number i of the arrival packet [y] is set. In step S124, the complement “1-i / n” is multiplied by the amplitude b and set as a new amplitude b. In step S125, “a + b” is set as the amplitude of the sample number i of the crossfade packet p ′. To do. In step S126, it is determined whether or not n samples have been processed based on whether or not the sample number i is updated (+1) and the value i is equal to the number of samples n. The process proceeds to step S121 until the sample number i is equal to the number of samples n. If the sample number i is equal to the number of samples n, the process proceeds to step S127, and “0” is set in the flag xfmode to indicate that the crossfade mode has ended. set.

  Instead of replacing the sample having the parity error with an interpolation value between the immediately preceding sample and the immediately following sample, the following treatment may be performed. For example, an erroneous packet is discarded. Further, if the number of errors is less than or equal to the predetermined value, an interpolation value can be used, and if the number of errors is greater than or equal to the predetermined value, the packets can be discarded. Further, the error data may be logically recovered by increasing the amount of parity data.

  While the present invention has been described according to the embodiment, the present invention is not limited to this. For example, the operation panel or keyboard may be removed from the musical sound generating terminal. In short, it is only necessary that the musical sound data generated based on the performance terminal transmitted via the network from the performance terminal capable of generating and transmitting the performance data can be received and produced by the same performance terminal via the network.

DESCRIPTION OF SYMBOLS 1 ... Musical sound generation terminal, 2 ... Performance terminal keyboard, 4, 9 ... Operation panel, 5 ... Sound source, 6, 10 ... Sound system, 7, 11 ... Control part, 12 ... LAN, 20 ... Microphone, 21 ... Microphone switch, 22 ... Monitor switch, 23 ... Ensemble switch, 24 ... Self-play switch, 31 ... Buffer, 33 ... Discrimination part, 34 ... First cross-fade part, 35 ... Second cross-fade part

Claims (2)

A musical sound generating terminal of an electronic musical instrument performance system that receives performance data from a performance terminal via a network, generates musical sound data based on the performance data, and transmits the musical sound data to the performance terminal via the network In
Receiving means for receiving a destination address transmitted from the performance terminal;
Detecting means for detecting whether the destination address received by the receiving means is a wide area address not indicating an individual destination; and
Assigning means for assigning an address to a performance terminal that has transmitted the wide-area address detected by the detecting means;
A musical sound generating terminal for an electronic musical instrument performance system, comprising: sending means for sending the address assigned by the assigning means to the network. An electronic musical instrument performance system for transmitting performance data by a performer to a musical tone generation terminal via a network, and receiving and generating musical tone data generated at the musical tone generation terminal based on the performance data via the network In the performance terminal of
A transmission means for transmitting an address request to the network using a wide-area address that does not individually indicate a transmission destination when starting the performance terminal;
Receiving means for receiving an address sent to the network in response to the address request;
A performance terminal for an electronic musical instrument performance system, comprising: transmission means for transmitting the performance data to the network using the received address as a destination address.

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