Patent Publication Number: US-2005120130-A1

Title: Data output device, data transmitting device, data processing system, data output method, data transmitting method, data processing method, their programs and recording media storing these programs

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to a data output device for outputting data, a data transmitting device for transmitting the data to a plurality of data output devices connected via a network, a data processing system that causes the plurality of data output devices to output the data transmitted from the data transmitting device via the network, a data output method, a data transmitting method, a data processing method, their programs and recording media storing these programs.  
      2. Description of Related Art  
      Conventionally, a configuration, in which and audio data transmitter for transmitting audio data and an audio reproducer for outputting the audio data transmitted from the audio data transmitter as sounds are connected to each other via a network, is known (refer to for example, Document 1: Japanese Unexamined Patent Publication No. 2001-298444, paragraph No. 0036 and  FIG. 1 ). In the configuration according to the Document 1, a CD player and a tuner as the audio data transmitter and a speaker as the audio reproducer are connected to each other via a serial bus as the network. In such configuration, when a plurality of speakers is connected to the tuner, such configuration that the serial buses are connected from the tuner to each of the speakers is conceivable.  
      When the serial buses are connected to each of the speakers, which are disposed in different distances from the tuner, it is conceivable such configuration that serial buses having different length corresponding to the distance from the tuner are connected to each of the speakers. However, in the above configuration, when audio data are output synchronously to each of the speakers from the tuner, generally, the transmission time of the audio data is proportional to the length of the serial buses. Accordingly, the times the audio data reach to each of the speakers differ from each other. As a result, sounds output from each of the speakers become asynchronous. Therefore, it is desired to provide such configuration that sounds are output synchronously from each of the speakers.  
     SUMMARY OF THE INVENTION  
      An object of the present invention is to provide a data output device that can output data transmitted via a network at the same time with other data output devices, a data transmitting device that can cause a plurality of data output devices connected via the network to output the data at the same time, a data processing system that can cause the plurality of data output devices to output the data transmitted from the data transmitting device via the network at the same time, a data output method, a data transmitting method, a data processing method, their programs and recording media storing these programs.  
      A plurality of data output devices according to an aspect of the present invention for respectively outputting data transmitted via a network, includes: an output information acquirer that acquires the data and delay time information about a delay time determined based on a transmission time of the data; and an output controller that causes the data to be output at the time based on the delay time of the delay time information.  
      A data transmitting device according to another aspect of the present invention that transmits data via a network to the above-described plurality of data output devices, includes: a transmission time calculating section for calculating a transmission time of the data for each of the data output devices; a delay information generator that generates the delay time information based on the transmission time; and a transmission controller that transmits the data and the delay time information to each of the data output devices via the network.  
      A data processing system according to still another aspect of the present invention includes: the above-described data output devices; and the above-described data transmitting device connected to the data output devices via the network, in which the output information acquirer acquires the data and the delay time information transmitted from the data transmitting device via the network.  
      A data processing system according to yet another aspect of the present invention includes: the above-described data output devices; and the above-described data transmitting device connected to the data output devices via the network, in which each of the data output devices include a confirmation information generator that, when receiving the confirmation request information transmitted from the data transmitting device via the network, generates the reception confirmation information and transmits the information to the data transmitting device via the network.  
      A data output method according to a further aspect of the present invention for outputting data to be transmitted via a network by a plurality of data output devices respectively, the method includes the steps of: acquiring the data and delay time information about a delay time determined based on a transmission time of the data; and outputting the data at the time based on the delay time of the delay time information.  
      A data transmitting method according to a still further aspect of the present invention for transmitting data via a network to a plurality of data output devices that output the data at the time based on a delay time determined based on a transmission time of the data, the method includes the steps of: calculating the transmission time of the data to each of the data output devices; generating delay time information about the delay time based on the transmission time; and transmitting the data and the delay time information to each of the data output devices via the network.  
      A data processing method according to a yet further aspect of the present invention for causing data, which is transmitted from a data transmitting device via a network, to be transmitted to each of a plurality of data output devices, the method includes the steps of: operating the data transmitting device to calculate a transmission time of the data to each of the data output devices; operating the data transmitting device to generate delay time information about a delay time determined based on the transmission time; operating the data transmitting device to transmit the data and the delay time information to each of the data output devices via the network; operating each of the data output devices to acquire the data and the delay time information transmitted from the data transmitting device via the network; and operating each of the data output devices to output the data at the time based on the delay time of the delay time information.  
      A data output program according to a yet further aspect of the present invention executes the above-described data output method by a computer.  
      A data transmitting program according to a yet further aspect of the present invention executes the above-described data transmitting method by a computer.  
      A data processing program according to a yet further aspect of the present invention executes the above-described data processing method by a computer.  
      A recording medium according to a yet further aspect of the present invention stores the above-described data output program in a manner readable by a computer.  
      A recording medium according to a yet further aspect of the present invention stores the above-described data transmitting program in a manner readable by a computer.  
      A recording medium according to a yet further aspect of the present invention stores the above-described data processing program in a manner readable by a computer. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a block diagram schematically showing the configuration of an AV data reproduction system according to an embodiment of the present invention;  
       FIG. 2  is a block diagram schematically showing the configuration of a data transmitting device in the embodiment;  
       FIG. 3  is a conceptual diagram schematically showing the configuration of frame data transmitted from the data transmitting device in the embodiment;  
       FIG. 4  is a conceptual diagram schematically showing the configuration of the frame data in the embodiment;  
       FIG. 5  is a block diagram schematically showing the configuration of an audio reproducer in the embodiment;  
       FIG. 6  is a flowchart showing frame data transmitting process in the data transmitting device according to the embodiment; and  
       FIG. 7  is a flowchart showing frame data receiving process in the audio reproducer according to the embodiment. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
      Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, an AV data reproduction system will be exemplified. In the example, a data transmitting device appropriately divides AV (Audio Video) data into a plurality of pieces of data to generate frame data; and based on the generated frame data and the like, the AV data are reproduced by a plurality of data reproducing devices. But the present invention is not limited to the above.  
       FIG. 1  is a block diagram schematically showing the configuration of the AV data reproduction system according to the embodiment.  FIG. 2  is a block diagram schematically showing the configuration of a data transmitting device.  FIG. 3  is a conceptual diagram schematically showing the configuration of frame data transmitted from the data transmitting device.  FIG. 4  is a conceptual diagram schematically showing the configuration of the frame data. And  FIG. 5  is a block diagram schematically showing the configuration of an audio reproducer.  
      [Configuration of AV Data Reproduction System] 
      In  FIG. 1 , reference numeral  100  denotes an AV data reproduction system as a data processing system. The AV data reproduction system (hereinafter, abbreviated to as reproduction system)  100  is a system for reproducing AV data, which are input from, for example, an unshown AV data output equipment. The reproduction system  100  includes a network  200 , a data transmitting device  300 , an audio reproducer  400 A as a data output device, an audio reproducer  400 B as a data output device, an audio reproducer  400 C as a data output device, an audio reproducer  400 D as a data output device and an unshown image reproducer. Hereinafter, when the audio reproducers  400 A,  400 B,  400 C and  400 D are described as a collective, these reproducers will be occasionally referred to as audio reproducer set  400 . Also, in this embodiment, a configuration will be exemplified in which the audio reproducer set  400  includes four audio reproducers. But if the number of the audio reproducer is a plural number, the number of the audio reproducer in the audio reproducer set  400  is not limited to four, but the number thereof may be five or more, or three or two.  
      The network  200  is connected to a data transmitting device  300 , the audio reproducers  400 A,  400 B,  400 C and  400 D, and the image reproducer. The network  200  connects the data transmitting device  300 , the audio reproducer set  400  and the image reproducer in a state that information can be transmitted and received. As the network  200 , for example, LAN (Local Area Network) such as intranet, extranet and Ethernet™based on multipurpose protocol suite such as TCP/IP (Transmission Control Protocol/Internet Protocol), a radio LAN complying IEEE (Institute of Electrical and Electronics Engineers) 802.1 X-Standard, a radio transmission network employing Bluetooth™, which is a near field communication and protocol, a network such as communication line network and broadcast network in which a plurality of base stations capable of transmitting and receiving information via radio medium form a network, and further, radio medium itself or cable medium itself which serves as a medium for directly transmitting and receiving information among the data transmitting device  300 , the audio reproducers  400 A,  400 B,  400 C,  400 D and the image reproducer are exemplified. Here, as the radio medium, any of the media such as electric wave, light, acoustic wave, electromagnetic wave is applicable. Also, as the cable medium, any medium such as cable, electricity wire, telephone cable complying with USB (Universal Serial Bus) standard and/or IEEE 1394 standard is applicable.  
      The data transmitting device  300  appropriately processes audio data SA, SB, SC and SD as the data of the AV data, which are input from the AV data output equipment, and transmits the data timely to the audio reproducers  400 A,  400 B,  400 C and  400 D. These audio data SA, SB, SC and SD are the data, for example, in one music composition, which are output as the sound respectively from the audio reproducers  400 A,  400 B,  400 C and  400 D. Also, the data transmitting device  300  appropriately processes the image data of the AV data, which are input from the AV data output equipment, and transmits the data timely to the image reproducer. As shown in  FIG. 2 , the data transmitting device  300  includes a communication unit  310 , a delay amount storage  320  as a storage, a delay amount determiner  330  as a transmission time calculating section, an audio data input unit  340  as a data acquiring section, a delay information generator  350  as a delay information generating section, a packet generator  360  as a transmission controller, an unshown image data transmitter, and the like.  
      The communication unit  310  is connected to the audio reproducers  400 A,  400 B,  400 C,  400 D and the image reproducer via the network  200 ; and further, connected to the delay amount determiner  330  and the packet generator  360 . The communication unit  310  is capable of receiving a transmission signal St from the audio reproducer set  400  and the image reproducer via the network  200 . When acquiring the transmission signal St, the communication unit  310  carries out a preset input interface processing to output a determination signal Sk to the delay amount determiner  330 , or a packet signal Sp to the packet generator  360 . Also, when acquiring the determination signal Sk from the delay amount determiner  330  or the packet signal Sp from the packet generator  360 , the communication unit  310  carries out a preset output interface to transmit the signal as the transmission signal St timely to the audio reproducer set  400  via the network  200 . Further, when acquiring an image data signal from the image data transmitter, the communication unit  310  carries out a preset output interface to transmit the signal as an image data transmission signal timely to the image reproducer via the network  200 .  
      The delay amount storage  320  is connected to the delay amount determiner  330  and the delay information generator  350 . The delay amount storage  320  stores various kinds of information about the transmission time of the audio data to the audio reproducer set  400 , which is generated by the delay amount determiner  330 , so as to be read out timely. As for the delay amount storage  320 , a DRAM (Dynamic Random Access Memory) or SRAM (Static Random Access Memory) is exemplified. Also, the delay amount storage  320  stores various kinds of programs and the like for controlling the operation of the entire data transmitting device  300 .  
      The delay amount determiner  330  is a program. The delay amount determiner  330  generates various kinds of information about the transmission time of the audio data to the audio reproducer set  400 , and causes the delay amount storage  320  to store the generated various kinds of information. Specifically, the delay amount determiner  330  generates ACK request information as confirmation request information, which requests on the audio reproducer set  400  to transmit an ACK (Acknowledge) as reception confirmation information, which will be described later. And the delay amount determiner  330  appropriately converts the ACK request information to the determination signal Sk, and outputs the signal to the communication unit  310 . In the following description, the processing to output the ACK request information will be occasionally referred to as processing to carry out polling.  
      After that, based on the determination signal Sk input from the communication unit  310 , the delay amount determiner  330  recognizes the ACK written in the determination signal Sk. And the delay amount determiner  330  recognizes that the device, which has transmitted the ACK, for example, is the audio reproducer  400 A, based on the inherent information-to-device written in the ACK, which will be described later. Further, the delay amount determiner  330  recognizes necessary time from a time when the ACK request information is output to a time when the ACK is acquired based on the time measured by an unshown timer, and recognizes a half value of the recognized necessary time as a delay time Da for the transmission time of the audio reproducer  400 A. The delay amount determiner  330  appropriately converts the recognized delay time Da to a memory signal Sm, and causes the delay amount storage  320  to store the signal so as to be read out appropriately. Further, the delay amount determiner  330  carries out the same processing as the above to recognize the delay times Db, Dc and Dd as the transmission time of the audio reproducers  400 B,  400 C and  400 D, and appropriately converts the recognized delay times Db, Dc and Dd to the memory signals Sm, and causes the delay amount storage  320  to store the signals so as to be read out appropriately. Hereinafter, when the delay times Da, Db, Dc and Dd are described as a collective, these delay times will be occasionally referred to as delay times Dz.  
      When the delay amount determiner  330  recognizes that all of the delay times Da, Db, Dc and Dd have been stored in the delay amount storage  320 , the delay amount determiner  330  reads out the delay times Da, Db, Dc and Dd stored in the delay amount storage  320  as the memory signals Sm. After that, the delay amount determiner  330  determines the delay time, which has the longest time in the read out delay times Da, Db, Dc and Dd as a reference time Dx. The delay amount determiner  330  calculates a difference between the reference time Dx and, for example, the delay time Da, and recognizes the calculated value as the differential time Ta of the audio reproducer  400 A. After that, the delay amount determiner  330  appropriately converts the recognized differential time Ta to a memory signal Sm and causes the delay amount storage  320  to store the memory signal Sm so as to be read out timely. Further, the delay amount determiner  330  carries out the same processing as the above; thereby, it calculates the differential times Tb, Tc and Td of the audio reproducers  400 B,  400 C and  400 D, appropriately, converts these calculated differential times Tb, Tc and Td to the memory signals Sm, and causes the delay amount storage  320  to store so as to be read out timely. Hereinafter, when the differential times Ta, Tb, Tc and Td are described as a collective, these differential times will be occasionally referred to as differential times Tz.  
      The delay amount determiner  330  timely acquires current time from the timer. When the delay amount determiner  330  recognizes that a preset time Ts has passed, the delay amount determiner  330  deletes the delay times Dz and the differential times Tz stored in the delay amount storage  320 . Hereinafter, when the delay times Dz and the differential times Tz are described as a collective, these delay times Dz and the differential times Tz will be occasionally referred to as transmission time information.  
      The audio data input unit  340  includes an audio input terminal  340 A, an audio input terminal  340 B, an audio input terminal  340 C and an audio input terminal  340 D. The audio input terminal  340 A includes, for example, a connector, which is connected detachably with not shown plug, a terminal, which is connected with a lead wire, and the like. An AV data output equipment, which outputs the AV data, is connected detachably to the audio input terminal  340 A, and output signal Sxa, which is written with audio data SA of the AV data to be output from the AV data output equipment, is input therefrom. The audio input terminals  340 B,  340 C and  340 D are also constituted in the same manner as the audio input terminal  340 A. To these audio input terminals  340 B,  340 C and  340 D, the output signals Sxb, Sxc and Sxd written with the audio data SB, SC and SD of the AV data, which are output synchronously along with the output signal SA from the AV data output equipment, are input respectively.  
      The delay information generator  350  is a program. The delay information generator  350  generates delay time information based on the differential times Tz stored in the delay amount storage  320 , and outputs the information to the packet generator  360 . Specifically, when recognizing that the differential times Tz have been stored in the delay amount storage  320 , the delay information generator  350  reads out the differential times Tz as a memory signal Sv respectively. For example, the delay information generator  350  then generates information for requesting on the audio reproducer  400 A to output the divided audio data SA 1 , which is a header portion of the audio data SA, at the time when the predetermined time U and the differential time Ta have passed from the time when the frame data  501  stored with the packet data  521  (described later) is acquired. Additionally, the delay information generator  350  generates information for requesting on the audio reproducer  400 B to output the divided audio data SB 1 , which is a header portion of the audio data SB, when the predetermined time U and the differential time Th have passed from the time when the frame data  501  stored with the packet data  531  (described later) are acquired. Still additionally, the delay information generator  350  generates information for requesting on the audio reproducer  400 C to output the divided audio data SC 1 , which is a header portion of the audio data SC, at the time when the predetermined time U and the differential time Tc have passed from the time when the frame data  501  stored with the packet data  541  (described later) are acquired. Further, the delay information generator  350  generates information for requesting on the audio reproducer  400 D to output the divided audio data SD 1 , which is a header portion of the audio data SD, at the time when the predetermined time U and the differential time Td have passed from the time when the frame data  501  stored with the packet data  551  (described later) are acquired. Finally, the delay information generator  350  generates delay time information having these various kinds of information generated in the above-described manner. After that, the generated delay time information is appropriately converted to a process signal Sz and output to the packet generator  360 .  
      The packet generator  360  is a program. This packet generator  360  is connected to audio input terminals  340 A,  340 B,  340 C and  340 D. The packet generator  360  sequentially generates frame data  50   n ,  50 ( n + 1 ), . . . (n is a natural number) as shown in  FIG. 3 , based on the audio data SA, SB, SC and SD input from the audio input terminals  340 A,  340 B,  340 C and  340 D and the delay time information input from the delay information generator  350 , and transmits the data to the audio reproducer set  400 .  
      Here, first of all, the configuration of the frame data  50   n  will be described. As shown in  FIG. 4 , the frame data  50   n  includes a frame header  51   n  (n is a natural number), a packet data  52   n  (n is a natural number), a packet data  53   n  (n is a natural number), a packet data  54   n  (n is a natural number), a packet data  55   n  (n is a natural number) and a delay packet data  56   n  (n is a natural number). The packet data  52   n ,  53   n ,  54   n  and  55   n  have substantially the same configuration with each other. Therefore, the packet data  52   n  will be described in detail below.  
      In the frame header  51   n , various kinds of information about the frame data  50   n  are stored. Specifically, the frame header  51   n  stores sync (synchronous)  51   n A (n is a natural number), which is a signal for synchronizing, SOF (Start Of Frame)  51   n B (n is a natural number) indicating the head of the frame data  50   n , frame number  51   n C (n is a natural number) indicating that the frame data  50   n  are the n-th frame data, and CRC (Cyclic Redundancy Check character)  51   n D (n is a natural number), which is a signal for detecting transmission error.  
      The packet data  52   n  are data used for output processing of the audio data SA in the audio reproducer  400 A. The packet data  52   n  includes a segment-determining data area  52   n A in which information about the packet data  52   n  is stored, and an AV data area  52   n B in which information about the audio data SA to be output by the audio reproducer  400 A is stored. Specifically, in the AV data area  52   n B, divided audio data SAn (n is a natural number) as a divided data, which are a partial data of the audio data SA, and data sync (Data Synchronous)  52   n E, which is a signal indicating the start of the divided audio data SAn, are stored. In the segment-determining data area  52   n A, receiver number  52   n C, which is, for example, an ID (Identification) number for identifying the audio reproducer  400 A, and segment number  52   n D as order information indicating that the divided audio data SAn are the n-th data from the head of the audio data SA are stored.  
      The packet data  53   n ,  54   n  and  55   n  are the data used for output processing of the audio data SB, SC and SD in the audio reproducers  400 B,  400 C and  400 D. The packet data  53   n ,  54   n  and  55   n  include, the segment-determining data area  53   n A,  54   n A and  55   n A stored with, same as the segment-determining data area  52   n A, various kinds of information, and AV data area  53   n B,  54   n B and  55   n B stored with, same as the AV data area  52   n B, various kinds of information such as, for example, divided audio data SBn (n is a natural number), SCn (n is a natural number) and SDn (n is a natural number) as the divided data.  
      The delay packet data  56   n  is stored with the various kinds of information about the delay time information. The delay packet data  56   n  includes a delay information storage area  56   n A stored with the delay time information, and a sync area  56   n B stored with a delay information sync (Synchronous) as a signal indicating the start of the delay time information.  
      Incidentally, the configuration of the frame data  50   n  is not limited to the above-described configuration, but another appropriate configuration may be employed.  
      Next, the process to generate the frame data  50   n  in the packet generator  360  will be described.  
      When acquiring output signals Sxa, Sxb, Sxc and Sxd simultaneously input from the audio input terminals  340 A,  340 B,  340 C and  340 D, the packet generator  360  recognizes the audio data SA, SB, SC and SD written in the acquired output signals Sxa, Sxb, Sxc and Sxd. Then, the packet generator  360  reads out the data of the predetermined data amount from the head position of, for example, the audio data SA. After that, data sync  521 E, receiver number  521 C and segment number  521 D corresponding to the divided audio data Sa 1  are generated respectively, and packet data  521 , which store these various kinds of information, are generated. Also, the packet generator  360  recognizes the audio data SB, SC and SD written in the acquired output signals Sxb, Sxc and Sxd. And the packet generator  370  carries out the same processing as the above to generate the packet data  521 , and generates the packet data  531 ,  541  and  551  stored with the divided audio data SB 1 , SC 1  and SD 1  respectively.  
      Further, when acquiring the process signal Sz input from the delay information generator  350 , the packet generator  360  recognizes the delay time information written in the acquired process signal Sz and generates the delay information sync. Owing to this, the packet generator  360  generates a delay packet data  561  stored with the delay time information and the delay information sync.  
      Further, the packet generator  360  generates a frame header  511 . And frame data  501 , which store the generated frame header  511 , packet data  521 ,  531 ,  541  and  551  and delay packet data  561 , are generated, and the generated frame data  501  are timely converted to a packet signal Sp and output to the communication unit  310 . In the following description, the time when the frame data  501  are output will be occasionally referred to as frame output time.  
      Then, the packet generator  360  carries out the same processing as described above; thereby, the frame data  502  are generated and output to the communication unit  310 , for example, 1 msec later from the frame output time. Specifically, for example, the data of the predetermined data amount are read out as the divided audio data SA 2  from the tail position of the divided audio data Sa 1  in the audio data SA. And packet data  522 , which stores the read out divided audio data SA 2  and the like, are generated. Further, the packet generator  360  carries out the same processing to generate packet data  532 ,  542  and  552  stored with the divided audio data SB 2 , SC 2  and SD 2  and the like. Further, in the case that the process signal Sz is newly input from the delay information generator  350 , the packet generator  360  generates a delay packet data  562  stored with the delay time information written in the input process signal Sz, whereas, in the case that the process signal Sz is not newly input therefrom, the packet generator  360  generates a packet data  562  stored with the delay time information written in the process signal Sz, which is input at the latest timing. Further, the packet generator  360  generates a frame header  512 . And frame data  502 , which store the frame header  512 , packet data  522 ,  532 ,  542  and  552  and delay packet data  562 , are generated, and the generated frame data  502  are timely converted to a packet signal Sp and output to the communication unit  310 . And the packet generator  370  converts the generated frame data  502  to the packet signal Sp and outputs the signal to the communication unit  310  1 msec later from the frame output time.  
      After that, the packet generator  360  generates the frame data  503 ,  504 , sequentially, and outputs these generated frame data  503 ,  504 , . . . sequentially to the communication unit  310  every 1 msec. Here, the configuration in which the frame data  50   n  are output every 1 msec, is exemplified. However, the configuration is not limited to the above. For example, such configuration that the frame data  50   n  are output every 5 msec or 10 msec may be adopted.  
      The audio reproducers  400 A,  400 B,  400 C and  400 D are connected to the data transmitting device  300  via the network  200  so that various kinds of information can be transmitted and received therebetween. Since the audio reproducers  400 A,  400 B,  400 C and  400 D have the same configuration each other, the audio reproducer  400 A will be described below.  
      The audio reproducer  400 A acquires the frame data  50   n , which are transmitted from the data transmitting device  300 , and outputs the audio data SA appropriately based on the acquired frame data  50   n . As shown in  FIG. 5 , the audio reproducer  400 A includes a communication unit  410 , a data storage  420 , a data reproducing unit  430  and the like.  
      The communication unit  410  is connected to the data transmitting device  300  via the network  200  as well as the data storage  420  and the data reproducing unit  430 . The communication unit  410  receives a reception signal Su from the data transmitting device  300  via the network  200 . When the frame data  50   n  are written in the received reception signal Su, the frame data  50   n  are appropriately converted to memory signals Sq and output to the data storage  420 . When ACK request information is written in the received reception signal Su, the ACK request information is appropriately converted to reproduction signal Se and output to the data reproducing unit  430 . Also, when the communication unit  410  acquires the reproduction signal Se from the data reproducing unit  430 , the communication unit  410  carries out a preset output interface to transmit the reception signal Su to the data transmitting device  300  via the network  200 .  
      The data storage  420  is connected to the data reproducing unit  430 . The data storage  420  stores the frame data  50   n  so as to be read out appropriately. As for the data storage  420 , a DRAM (Dynamic Random Access Memory), a SRAM (Static Random Access Memory), or the like may be exemplified. Also, the data storage  420  stores various kinds of programs and the like for controlling the operation of the entire audio reproducer  400 A.  
      The data reproducing unit  430  includes a various kinds of programs such as an ACK (Acknowledge) generator  431  as an confirmation information generator, a data output section  432  and a reproduction controller  433  as an output information acquirer and an output controller, a frame data receiver, a divided data acquiring section and a data generator.  
      The ACK generator  431  generates, so to speak, an ACK, which is a piece of information indicating the fact that ACK request information transmitted from the data transmitting device  300  has been acquired. Specifically, based on the reproduction signal Se input from the communication unit  410 , the ACK generator  431  recognizes the ACK request information written in the reproduction signal Se. And the ACK generator  431  generates ACK including information indicating the fact that the ACK request information has been acquired, the inherent information-to-device for identifying the audio reproducer  400 A and the like. After that, the generated ACK is appropriately converted to a reproduction signal Se and output to the communication unit  410 .  
      The data output section  432  has a sound generator such as, for example, unshown speaker. The data output section  432  is controlled by the reproduction controller  433  to output audio data SA as sounds via the sound generator.  
      The reproduction controller  433  timely reads out the divided audio data SAn, SA(n+1), . . . stored with the frame data  50   n ,  50 ( n + 1 ), . . . stored in the data storage  420 , and the delay time information. The reproduction controller  433  timely carries out a processing to combine these read out divided audio data SAn, SA(n+1), . . . with each other and controls the data output section  432  to output the data as the audio data SA, based on the time corresponding to the delay time information. Specifically, the reproduction controller  433  timely reads out the frame data  50   n ,  50 ( n + 1 ), . . . stored in the data storage  420  as a memory signal Sr. Based on the receiver numbers  52   n C,  52 ( n + 1 )C, . . . of the read out frame data  50   n ,  50 ( n + 1 ), . . . , the packet data  52   n ,  52 ( n + 1 ), . . . are identified and appropriately acquired. Further, the delay packet data  56   n ,  56 ( n + 1 ), . . . stored in the frame data  50   n ,  50 ( n + 1 ), . . . are acquired. After that, the divided audio data SAn, SA(n+ 1 ), . . . are appropriately combined with each other based on the order indicated in the segment numbers  52   n D,  52 ( n + 1 )D, . . . of the packet data  52   n ,  52 ( n + 1 ), . . . , and causes the data output section  432  to output the data as the audio data SA at the time written in the delay time information stored in the delay packet data  56   n ,  56 ( n + 1 ), . . .  
      The image reproducer is connected to the data transmitting device  300  via the network  200  so that various kinds of information can be transmitted and received therebetween. The image reproducer includes an unshown communication unit, a data storage, a data reproducing unit and the like. The communication unit acquires image data transmitted from the data transmitting device  300 , and causes the data storage to store the data so as to be read out timely. The data reproducing unit timely reads out the image data stored in the data storage to output the image.  
      [Operation of AV Data Reproduction System] 
      Next, the operation of the reproduction system  100  will be described with reference to the related drawings. In the following description, a case where the delay time Da of the audio reproducer  400 A is 4 msec; the delay time Db, Dd of the audio reproducers  400 B and  400 D is 5 msec; and the delay time Dc of the audio reproducer  400 C is 3 msec, will be exemplified.  
      (Frame Data Transmitting Process in Data Transmitting Device) First of all, as the operation of the reproduction system  100 , the transmission process of the frame data  50   n  in the data transmitting device  300  will be described with reference to  FIG. 6 .  FIG. 6  is a flowchart showing the frame data transmitting process in the data transmitting device.  
      As shown in  FIG. 6 , a user turns ON the power supply for the reproduction system  100  to supply the power. When the power is supplied, the delay amount determiner  330  of the data transmitting device  300  generates the ACK request information, and carries out the processing to transmit the generated ACK request information to the audio reproducer set  400 ; i.e., the polling (step S 101 ). Here, the configuration in which the polling is carried out immediately after the power is supplied, is exemplified. However, the configuration is not limited to the above. For example, such configuration in which the polling is not carried out immediately after the power is supplied; but for example, when a setting input requesting to carry out the polling is made by the user, the polling is carried out, may be employed.  
      After that, the delay amount determiner  330  carries out the processing to determine whether or not the ACKs have been received from the audio reproducer set  400  (step S 102 ).  
      In step S 102 , when it is determined that the ACKs have not been received from audio reproducer set  400 , the processing returns to step S 101 .  
      On the other hand, in step S 102 , when it is determined that the ACKs have been received from the audio reproducer set  400 , the delay amount determiner  330  calculates the delay times Dz based on the necessary time from a point when the polling is carried out to a point when the respective ACKs of the audio reproducers  400 A,  400 B,  400 C and  400 D are acquired (step S 103 ). And the calculated delay times Dz are stored in the delay amount storage  320  so as to be read out timely.  
      Then, when the delay amount determiner  330  recognizes that delay times Dz have been stored in the delay amount storage  320 , the delay amount determiner  330  determines the longest delay time in the stored delay times Dz as the reference time Dx (step S 104 ). Here, 5 msec of the delay times Db and Dd is determined as the reference times Dx.  
      After that, the delay amount determiner  330  calculates the differential times Tz of the audio reproducers  400 A,  400 B,  400 C and  400 D based on the delay times Dz calculated in step S 103  and the reference times Dx determined in step S 104  (step S 105 ). Here the differential time Ta is 1 msec; the differential times Tb and Td are 0 msec; and the differential time Tc is 2 msec. And these calculated differential times Tz are stored in the delay amount storage  320  so as to be read out timely (step S 106 ).  
      After that, the data transmitting device  300 , with the use of the delay information generator  350 , generates the delay time information based on the differential times Tz stored in the delay amount storage  320  (step S 107 ). Here, such delay time information are generated, which include information that requests on the audio reproducer  400 A to output the divided audio data Sa 1  at the time when the predetermined time U and the differential time Ta have passed from the time when the frame data  501  are acquired, i.e., at the time when the predetermined time U and 1 msec have passed from a time when the frame data  501  are acquired; information that request on the audio reproducers  400 B and  400 D to respectively output the divided audio data SB 1  and SD 1  at the time when the predetermined time U and the differential times Tb and Td have passed from the time when the frame data  501  are acquired, i.e., at the time when the predetermined time U has passed from the time when the frame data  501  are acquired; and information that requests on the audio reproducer  400 C to output the divided audio data SC 1  at the time when the predetermined time U and the differential time Tc have passed from the time when the frame data  501  are acquired, i.e., at the time when the predetermined time U and 2 msec have passed from the time when the frame data  501  are acquired.  
      The data transmitting device  300  generates the frame data  501 ,  502 , . . . as shown in  FIG. 3  based on the delay time information generated in step S 107  and the audio data SA, SB, SC and SD input from the audio data input unit  340  (step S 108 ). And the generated frame data  501 ,  502 , . . . are transmitted to the audio reproducers  400 A,  400 B,  400 C and  400 D, for example, every 1 msec (step S 109 ).  
      After that, the data transmitting device  300  determines whether or not the time since, for example, the delay times Dz are calculated has exceeded 5 minutes, which is a preset time Ts previously set, with the use of the delay amount determiner  330  (step S 110 ). Here, the configuration, in which it is determined whether or not that the time from the delay times Dz are calculated has exceeded the preset time Ts, is exemplified. The configuration is not limited to the above. Such configuration that, for example, it is determined whether or not that the time from the time when the differential times Tz are stored in the delay amount storage  320  or the time when the polling is carried out or the like has exceeded the preset time Ts, may be employed. Also, such configuration that the preset time Ts is 5 minutes is exemplified. However, the configuration is not limited to the above. For example, the preset time Ts may be set to 10 minutes or 30 minutes.  
      In step S 110 , when the delay amount determiner  330  determines that the preset time Ts has not passed, the processing returns to step S 107 . On the other hand, in step S 110 , when the delay amount determiner  330  determines that the preset time Ts has passed, the transmission time information stored in the delay amount storage  320 , i.e., the delay times Dz and the differential times Tz are deleted (step S 111 ). Then, the processing returns to step S 101 , and carries out the polling again.  
      (Frame Data Receiving Process in Audio Reproducer)  
      Next, as the operation of the reproduction system  100 , the reception processing of the frame data  50   n  in the audio reproducer set  400  will be described with reference to  FIG. 7 .  FIG. 7  is a flowchart showing the frame data receiving process in the audio reproducer.  
      As shown in  FIG. 7 , for example, when the audio reproducer  400 A recognizes that the ACK generator  431  has received ACK request information; i.e., a polling, which is transmitted from the data transmitting device  300  (step S 201 ), the audio reproducer  400 A generates an ACK. The generated ACK is transmitted to the data transmitting device  300  (step S 202 ). The audio reproducers  400 B,  400 C and  400 D also carry out the processing from step S 201  to step S 203 .  
      After that, when the communication unit  410  receives the frame data  501 ,  502 , . . . shown in  FIG. 3 , which are transmitted from the data transmitting device  300  (step S 203 ), the audio reproducers  400 A,  400 B,  400 C and  400 D cause the data storage  420  to store the received frame data  501 ,  502 , . . . so as to be read out timely (step S 204 ). As described above, the frame data  501 ,  502 , . . . are transmitted from the data transmitting device  300  at 1 msec intervals from the frame output time. Since the delay time Da is 4 msec; the delay times Db and Dd are 5 msec; and the delay time Dc is 3 msec, the audio reproducer  400 C receives the frame data  501 , 3 msec later from the frame output time; the audio reproducer  400 A receives the frame data  501 , 4 msec later from the frame output time; and the audio reproducers  400 B and  400 D receive the frame data  501 , 5 msec later from the frame output time. After that, the audio reproducers  400 A,  400 B,  400 C and  400 D receive the frame data  502 ,  503 , . . . sequentially every 1 msec.  
      And, for example, when the reproduction controller  433  recognizes that the frame data  501 ,  502 , . . . have been stored in the data storage  420 , the audio reproducer  400 A timely acquires the divided audio data SA 1 , SA 2 , . . . stored in the frame data  501 ,  502 , . . . and the delay time information (step S 205 ). The audio data SA are reproduced based on the acquired divided audio data SA 1 , SA 2 , . . . and the delay time information (step S 206 ).  
      Specifically, based on the receiver numbers  521 C,  522 C, . . . , the audio reproducer  400 A acquires the packet data  521 ,  522 , . . . timely from the frame data  501 ,  502 , . . . using the reproduction controller  433 . Additionally, the audio reproducer  400 A appropriately acquires the delay time information from the frame data  501 ,  502 , . . . . Then, the reproduction controller  433  acquires the divided audio data SA 1 , SA 2 , . . . based on the segment numbers  521 D,  522 D, . . . of the acquired packet data  521 ,  522 , . . . , and properly combines these divided audio data SA 1 , SA 2 , . . . with each other in accordance with the predetermined order. The reproduction controller  433  causes the data output section  432  to output the divided audio data Sa 1 , which is the header portion of the audio data SA, as sounds at the time written in the delay time information. In other words, the reproduction controller  433  starts the reproduction processing of the audio data SA. After that, the data output section  432  is made to output the divided audio data SA 2  combined with the tail position of the divided audio data SA 1 , the divided audio data SA 3  combined with the tail position of the divided audio data SA 2 , and the like successively. Owing to this, the audio data SA are output from the data output section  432 . Note that, information written in the delay time information is the one that requests to output the audio data SA at the time when the predetermined time U and 1 msec have passed from the time when the frame data  501  are acquired. Additionally, as described above, the audio reproducer  400 A has been acquired the frame data  501 , at the time when 5 msec has passed from the frame output time. Accordingly, the audio reproducer  400 A starts the reproduction processing of the audio data SA at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 .  
      The audio reproducers  400 B,  400 C and  400 D also carry out the processing step S 205  and step S 206 .  
      Specifically, the audio reproducer  400 B appropriately acquires the divided audio data SB 1 , SB 2 , . . . stored in the frame data  501 ,  502 , . . . and the delay time information, with the use of the reproduction controller  433 . Next, the reproduction controller  433  appropriately combines the divided audio data SB 1 , SB 2 , . . . with each other in accordance with the predetermined order. The audio reproducer  400 B causes the data output section  432  to output the divided audio data SB 1 , which is the header portion of the audio data SB, as sounds at the time written in the delay time information. In other words, the reproduction controller  433  starts the reproduction processing of the audio data SB. Note that, information written in the delay time information is the one that requests to output the audio data SB at the time when the predetermined time U has passed from the time when the frame data  501  are acquired. Additionally, as described above, the audio reproducer  400 B acquires the frame data  501 , at the time when 5 msec has elapsed from the frame output time. Accordingly, the audio reproducer  400 B starts the reproduction processing of the audio data SB at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 .  
      Further, the audio reproducer  400 C appropriately acquires the divided audio data SC 1 , SC 2 , . . . stored in the frame data  501 ,  502 , . . . and the delay time information, with the use of the reproduction controller  433 . Next, the reproduction controller  433  appropriately combines the divided audio data SC 1 , SC 2 , . . . with each other in accordance with the predetermined order. The audio reproducer  400 C then causes the data output section  432  to output the divided audio data SC 1 , which is the header portion of the audio data SC, as sounds at the time written in the delay time information. In other words, the reproduction controller  433  starts the reproduction processing of the audio data SC. Note that, information written in the delay time information is the one that requests to output the audio data SC at the time when the predetermined time U and 2 msec have passed from the time when the frame data  501  are acquired. Additionally, as described above, the audio reproducer  400 C acquires the frame data  501 , at the time when 3 msec has passed from the frame output time. Accordingly, the audio reproducer  400 C starts the reproduction processing of the audio data SC at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 .  
      Further, the audio reproducer  400 D appropriately acquires the divided audio data SD 1 , SD 2 , . . . stored in the frame data  501 ,  502 , . . . and the delay time information, with the use of the reproduction controller  433 . Next, the reproduction controller  433  appropriately combines the divided audio data SD 1 , SD 2 , . . . with each other in accordance with the predetermined order. The audio reproducer  400 D then causes the data output section  432  to output the divided audio data SD 1 , which is the header portion of the audio data SD, as sounds at the time written in the delay time information. In other words, the reproduction controller  433  starts the reproduction processing of the audio data SD. Note that, information written in the delay time information is the one that requests to output the audio data SD at the time when the predetermined time U has passed from the time when the frame data  501  are acquired. Additionally, as described above, the audio reproducer  400 D acquires the frame data  501 , at the time when 5 msec has elapsed from the frame output time. Accordingly, the audio reproducer  400 D starts the reproduction processing of the audio data SD at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 .  
      After that, for example, the audio reproducer  400 A timely deletes the frame data  501 ,  502 , . . . stored in the data storage  420  using the reproduction controller  433  (step S 207 ). And the audio reproducer  400 A determines whether or not the ACK generator  431  has received the polling again (step S 208 ).  
      In step S 208 , when it is determined that the polling has been received, the processing returns to step S 202  and an ACK is generated and transmitted to the data transmitting device  300 . And the processing from step S 203  to step S 208  is carried out.  
      On the other hand, in step S 208 , when it is determined that the polling has not been received, the processing returns to step S 203  and the audio reproducer  400 A receives the frame data  50   n  transmitted from the data transmitting device  300  using the communication unit  410 . And the processing from step S 204  to step S 208  is carried out.  
      The audio reproducers  400 B,  400 C and  400 D also carry out the processing step S 207  and step S 208 .  
      According to the above-described embodiment, the data transmitting device  300  in the reproduction system  100  calculates the delay time Da of the audio reproducer  400 A as, for example, 4 msec; the delay time Db and Dd of the audio reproducers  400 B and  400 D as, for example, 5 msec; and the delay time Dc of the audio reproducer  400 C as, for example, 3 msec using the delay amount determiner  330 . And based on the delay times Dz, the differential time Ta of the audio reproducer  400 A is calculated as 1 msec; the differential times Th and Td of the audio reproducers  400 B and  400 D are calculated as 0 msec; and the differential time Tc of the audio reproducer  400 C is calculated as 2 msec. After that, the delay information generator  350  generates the output request information based on the differential times Tz. More specifically, the delay information generator  350  generates such delay time information, including information that requests on the audio reproducer  400 A to output the divided audio data Sa 1  at the time when the predetermined time U and 1 msec, which is the differential time Ta, have passed from the time when the packet data  521  are acquired; information that request on the audio reproducers  400 B and  400 D to output the divided audio data SB 1  and SD 1  at the time when the predetermined time U and 0 msec, which is the differential times Th and Td, have passed from the time when the packet data  531  and  551  are acquired; and information that requests on the audio reproducer  400 C to output the divided audio data SC 1  at the time when the predetermined time U and 2 msec, which is the differential time Tc, have passed from the time when the packet data  541  are acquired. Then, the packet data  521 ,  531 ,  541  and  551  stored with the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , and the delay time information are transmitted to the audio reproducer set  400 .  
      Consequently, the audio reproducers  400 B and  400 D acquire the packet data  531  and  551 , and the delay time information at the time when only 5 msec, which is the delay time Db and Dd, has passed from the frame output time. Then, the audio reproducers  400 B and  400 D output the divided audio data SB 1  and SD 1  at the time when the predetermined time U has passed from the time when the packet data  531  and  551  are acquired based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 . Further, the audio reproducer  400 A receives the packet data  521  and the delay time information at the time when only 4 msec, which is the delay time Da, has passed from the frame output time. Then, the audio reproducer  400 A outputs the divided audio data Sa 1  at the time when the predetermined time U and 1 msec have passed from the time when the packet data  521  are acquired based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 . Further, the audio reproducer  400 C receives the packet data  541  and the delay time information at the time when 3 msec, which is the delay time Dc, has passed from the frame output time. Then, the audio reproducers  400 C outputs the divided audio data SC 1  at the time when the predetermined time U and 2 msec have passed from a time that the packet data  541  are acquired based on the delay time information, i.e., when the predetermined time U and 5 msec have passed from the frame output time, with the use of the reproduction controller  433 . Accordingly, the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , which are the header portions of the audio data SA, SB, SC and SD, at the same time.  
      Also, the data transmitting device  300  acquires audio data SA, SB, SC and SD, which are input from the AV data output equipment, using the audio data input unit  340 . And the packet generator  360  timely transmits the divided audio data SAn, SBn, SCn and SDn of the audio data SA, SB, SC and SD, which are acquired by the audio data input unit  340 , to the audio reproducer set  400 . Owing to this, since it is not necessary to provide any storage for storing the audio data SA, SB, SC and SD to the data transmitting device  300 , the configuration of the data transmitting device  300  can be simplified. Also, the cost of the data transmitting device  300  can be reduced as well as the data transmitting device  300  can be miniaturized.  
      The data transmitting device  300  is provided with the delay amount storage  320 , which stores the delay times Dz calculated by the delay amount determiner  330 . Then, the data transmitting device  300  generates the delay time information based on the differential times Tz calculated from the differential times Dz stored in the delay amount storage  320  with the use of the delay information generator  350 . Owing to this, for example, when transmitting the divided audio data SA 1 , SB 1 , SC 1  and SD 1  of the audio data SA, SB, SC and SD of a new music composition, the data transmitting device  300  can use the differential times Tz, which are calculated from the delay times Dz stored in the delay amount storage  320 , to generate the delay time information with the use of the delay information generator  350 ; and thus, it is possible to eliminate the processing to newly calculate the delay times Dz using the delay amount determiner  330 . Accordingly, the processing to transmit the divided audio data SA 1 , SB 1 , SC 1  and SD 1  can be carried out more swiftly.  
      The data transmitting device  300  calculates the delay times Dz first using the delay amount determiner  330 , and then, determines whether or not the preset times Ts are exceeded. And when it is determined as exceeded, the data transmitting device  300  calculates the delay times Dz again. Accordingly, the data transmitting device  300 , even when the differential times Dz are altered, can generates the delay time information based on the differential times Tz calculated from the corresponding recalculated delay times Dz, and appropriately transmits the information to the audio reproducer set  400 . Accordingly, the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to carry out the processing to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1  at the same time more appropriately. As for the cause why the delay times Dz alter, it is conceivable as one example. That is, for example, in such configuration that the network  200  includes a radio medium, between the data transmitting device  300  and, for example, the audio reproducer  400 A, a foreign object is disposed altering the transmission path of the frame data  50   n.    
      The data transmitting device  300 , with the use of the delay amount determiner  330 , generates the ACK request information and transmits the information to the audio reproducer set  400 . Besides, the delay times Dz are calculated based on the necessary time from a time when the ACK request information are transmitted to a time when the ACKs are acquired. And when the audio reproducers  400 A,  400 B,  400 C and  400 D acquire the ACK request information using the ACK generator  431 , the ACKs are made to generate and transmitted to the data transmitting device  300 . Owing to this, the delay amount determiner  330  can calculate the delay times Dz in such simple manner; i.e., by just recognizing that the necessary time from the time when the ACK request information is generated and transmitted to the audio reproducer set  400  to the time when the ACK is acquired. Accordingly, the processing to calculate the delay times Dz more swiftly. Also, the configuration of the delay amount determiner  330  can be simplified.  
      The data transmitting device  300 , with the use of the packet generator  360 , generates the packet data  52   n ,  53   n ,  54   n  and  55   n  stored with the divided audio data SAn, SBn, SCn and SDn, in which the audio data SA, SB, SC and SD are divided into a plurality of pieces of data, as well as the frame data  50   n ,  50 ( n + 1 ), . . . including the delay time information, and then transmits the data to the audio reproducer set  400 . And, for example, using the reproduction controller  433 , the audio reproducer  400 A acquires the frame data  50   n ,  50 ( n + 1 ), . . . transmitted from the data transmitting device  300 , and the packet data  52   n ,  52 ( n + 1 ), . . . are identified from the acquired frame data  50   n ,  50 ( n + 1 ), . . . , After that, the reproduction controller  433  acquires divided audio data SAn, SA(n+ 1 ), . . . , stored in the packet data  52   n ,  52 ( n + 1 ), . . . Further, the audio reproducers  400 B,  400 C and  400 D are also provided with the same function as that of the audio reproducer  400 A.  
      Owing to this, with one transmission of the frame data  50   n  using the packet generator  360 , the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to acquire the divided audio data SAn, SBn, SCn and SDn timely and simultaneously. Accordingly, compared to such configuration that the packet data  52   n ,  53   n ,  54   n  and  55   n  stored with the divided audio data SAn, SBn, SCn and SDn are transmitted independently, the number of the transmission of the data can be reduced; and thus, the processing load of the packet generator  360  can be reduced.  
      Further, the data transmitting device  300  transmits the frame data  50   n  including the divided audio data SAn, SBn, SCn and SDn, in which the audio data SA, SB, SC and SD are divided into a plurality of pieces, to the audio reproducer set  400 . And for example, the audio reproducer  400 A combines the divided audio data SAn, SA(n+ 1 ), . . . acquired from the frame data  50   n ,  50 ( n + 1 ), . . . , with each other, and outputs the data from the data output section  432  as the audio data SA. Further, the audio reproducers  400 B,  400 C and  400 D are also provided with the same function as that of the audio reproducer  400 A. Therefore, since the data transmitting device  300  transmits the audio data SA, SB, SC and SD to the audio reproducer set  400  by dividing these data into a plurality of pieces, the data amount per one transmission to the audio reproducer set  400  can be reduced. Accordingly, the data transmitting device  300  can swiftly transmits the audio data SA, SB, SC and SD to the audio reproducer set  400  even when the network  200  is, for example, in congestion.  
      For example, the audio reproducer  400 A recognizes the order of the divided audio data SAn in the audio data SA based on, for example, the segment number  52   n D of the packet data  52   n  using the reproduction controller  433 . The divided audio data SAn, SA(n+1), . . . are combined with each other in accordance with the recognized order to generate the audio data SA. Owing to this, the reproduction controller  433  can generate the audio data SA from the divided audio data SAn, SA(n+1), . . . in such a simple manner as just referring to the segment number  52   n D of the packet data  52   n . Accordingly, the processing to generate the audio data SA from the divided audio data SAn, SA (n+1) . . . can be carried out more swiftly.  
     MODIFICATION OF EMBODIMENT  
      The present invention is not limited to the above described embodiments, but the following modifications are included therein within a range where the object of the present invention can be achieved.  
      The following configuration has been exemplified; i.e., the audio data input unit  340  for acquiring the audio data SA, SB, SC and SD, which are input from the AV data output equipment, is provided to the data transmitting device  300 . However, for example, the following configuration may be employed. That is, in place of providing the audio data input unit  340 , such configuration that, for example, a storage for storing the AV data is provided, and the packet generator  360  transmits the audio data SA, SB, SC and SD of the AV data stored in the storage to the audio reproducer set  400 , may be employed. By adopting the configuration as described above, the process to connect between the AV data output equipment and the audio data input unit  340  can be eliminated resulting in an enhanced user-friendliness of the data transmitting device  300 .  
      The following configuration has been exemplified; i.e., in the packet generator  360  of the data transmitting device  300 , all of the frame data  50   n  include the delay packet data  56   n  stored with the delay time information. However, the configuration is not limited thereto, but, for example, following configuration can be adopted. That is, only the frame data  501  may include the delay packet data  56   n , while the frame data  502 ,  503 , . . . do not include the delay packet data  56   n . According to the above configuration, since the data amount of the frame data  502 ,  503 , . . . can be reduced, thus the frame data  502 ,  503 , . . . can swiftly be transmitted to the audio reproducer set  400  even when the network  200  is, for example, in congestion. Further, since the capacity of the data storage  420  in the audio reproducer set  400  for storing the frame data  50   n , can be reduced, the cost of the audio reproducer set  400  can be reduced.  
      The following configuration has been exemplified; i.e., the data transmitting device  300  is provided with the delay amount storage  320  for storing the delay times Dz. However, for example, the following configuration may be adopted. That is, in place of providing the delay amount storage  320 , each time when the packet generator  360  carries out the processing for transmitting, for instance, the audio data SA, SB, SC and SD of a new music composition, the delay amount determiner  330  can calculate the delay times Dz, and the delay information generator  350  can generate the delay time information based on the calculated delay times Dz. By adopting the configuration as described above, since it is not necessary to provide the delay amount storage  320  to the data transmitting device  300 , the configuration of the data transmitting device  300  can be simplified. Also, the cost of the data transmitting device  300  can be reduced as well as the data transmitting device  300  can be miniaturized. Further, since the data transmitting device  300  transmits the divided audio data SA 1 , SB 1 , SC 1  and SD 1  as well as the delay time information generated based on the latest delay times Dz, the processing to cause the audio reproducers  400 A,  400 B,  400 C and  400 D to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1  at the same time can be carried out more appropriately.  
      The following configuration has been exemplified; i.e., when the preset time Ts has elapsed after the delay times Dz are calculated, the delay amount determiner  330  in the data transmitting device  300  calculates the delay times Dz again. However, the configuration is not limited to the above, but, for example, the following configuration may be adopted. That is, such a configuration can be employed that the delay times Dz are calculated at each time when, for instance, the transmission of the audio data SA, SB, SC and SD of one or a plurality of music compositions is completed. By adopting such configuration, since the delay amount determiner  330  does not have to acquire the current time timely from the timer, the load of the delay amount determiner  330  can be reduced.  
      Further, the following configuration may be adopted; i.e., once the delay times Dz are calculated, the delay times Dz are not calculated until, for example, the power supply is turned OFF and ON again. By adopting such configuration, since the delay amount determiner  330  can reduce the number of times for calculating the delay times Dz, the processing load of the delay amount determiner can be reduced.  
      By adopting such configuration, since it is possible to reduce the number of times when the delay amount determiner  330  is made to calculate the delay times Dz, the load of the delay amount determiner  330  can be reduced. The following configuration has been exemplified; i.e., the delay amount determiner  330  in the data transmitting device  300  calculates the delay times Dz based on the necessary time from the time when ACK request information is transmitted to the time when the ACKs are received. However, the configuration is not limited to the above, but, for example, the following configuration may be adopted. Also, it is not necessary to provide the audio reproducer set  400  with the ACK generator  431 . Owing to this, the configuration of the data transmitting device  300  and the audio reproducer set  400  can be simplified.  
      The following configuration has been exemplified; i.e., for example, the reproduction controller  433  in the audio reproducer  400 A recognizes the order of the divided audio data SAn, SA(n+ 1 ), . . . based on, for example, the segment numbers  52   n D,  52 ( n + 1 )D . . . of the packet data  52   n ,  52 ( n + 1 ), . . . And the divided audio data SAn, SA(n+ 1 ), . . . may be combined with each other in accordance with the recognized order to generate the audio data SA. However, for example, such configuration may be adopted; i.e., for example, the divided audio data SAn, SA(n+ 1 ), . . . are combined with each other based on the order the packet data  52   n ,  52 ( n + 1 ), . . . stored in the data storage  420  to generate the audio data SA. By adopting such configuration, for example, since it is not necessary to store the segment number  52   n D in the packet data  52   n , the data amount of the packet data  52   n  can be reduced. Owing to this, the generating process and the transmitting process of the frame data  50   n  can be carried out more swiftly.  
      Further, the following configuration has been exemplified; i.e., the data transmitting device  300  divides the audio data SA, SB, SC and SD to a plurality of divided audio data SAn, SBn, SCn and SDn, and these divided audio data SAn, SBn, SCn and SDn etc. are transmitted to the audio reproducer set  400  stored with frame data  50   n . However, for example, the following configuration may be adopted.  
      That is, such a configuration is applicable that all of the audio data SA, SB, SC and SD as well as the delay time information are transmitted to the audio reproducers  400 A,  400 B,  400 C and  400 D without dividing the audio data SA, SB, SC and SD by the packet generator  360 . Further, such a configuration may also be applicable that the audio data SA, SB, SC and SD as well as the delay time information are respectively transmitted to the corresponding audio reproducers  400 A,  400 B,  400 C and  400 D. In such configuration also, owing to substantially the same effect as that in the above-described embodiment, the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to receive the audio data SA, SB, SC and SD at the substantially same time. Further, since there is no need to provide a function of generating the divided audio data SAn, SBn, SCn and SDn in the packet generator  360  of the data transmitting device  300 , the configuration of the packet generator  360  can be simplified. Furthermore, according to the configuration that the audio data SA, SB, SC and SD as well as the delay time information are respectively transmitted to the corresponding audio reproducers  400 A,  400 B,  400 C and  400 D, the data amount to be received by the audio reproducer set  400  can be reduced, compared to the configuration that all of the audio data SA, SB, SC and SD as well as the delay time information are transmitted thereto. Therefore, since the capacity of the data storage  420  in the audio reproducer set  400 , in which the audio data SA, SB, SC and SD respectively being corresponding to the audio reproducers  400 A,  400 B,  400 C and  400 D, etc. are stored, can be reduced, and thus the cost of the audio reproducer set  400  can be reduced.  
      In contrast, such a configuration is applicable that the packet data  52   n ,  53   n ,  54   n  and  55   n  as well as the delay time information are respectively transmitted to the corresponding audio reproducers  400 A,  400 B,  400 C and  400 D without the packet data  52   n ,  53   n ,  54   n  and  55   n  included in the frame data  50   n  by the packet generator  360 . With this configuration, according to the substantially same action as the above-described embodiment, the data transmitting device  300  still causes the audio reproducers  400 A,  400 B,  400 C and  400 D to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , which are the header portions of the audio data SA, SB, SC and SD at the same time. Also, compared to such configuration that the packet data  52   n ,  53   n ,  54   n  and  55   n  are transmitted as the frame data  50   n , the data amount to be received by the audio reproducer set  400  can be reduced. Therefore, since the capacity of the data storage  420  in the audio reproducer set  400 , in which the packet data  52   n ,  53   n ,  54   n  and  55   n  respectively being corresponding to the audio reproducers  400 A,  400 B,  400 C and  400 D, etc. are stored, can be reduced, and thus the cost of the audio reproducer set  400  can be reduced.  
      The following reproduction system  100  has been exemplified; i.e., the audio data SA, SB, SC and SD are output from each of the audio reproducers  400 A,  400 B,  400 C and  400 D at the same time. However, the configuration is not limited to the above, but, for example, the following configuration may be adopted. That is, in addition to the delay times Dz of the audio reproducers  400 A,  400 B,  400 C and  400 D, the delay amount determiner  330  in the data transmitting device  300  calculates the delay time De of the image reproducer. Then, the delay information generator  350  generates the delay time information based on the delay time De and the delay times Dz. Then, the packet generator  360  generates the packet data  52   n ,  53   n ,  54   n  and  55   n , which is the packet data stored with the divided image data with the image data divided into a plurality of pieces, as well as the frame data  50   n  including the delay time information. After that, the generated frame data  50   n  may be transmitted to the audio reproducers  400 A,  400 B,  400 C and  400 D and the image reproducer. By adopting such configuration, the audio data SA, SB, SC and SD, and the image data can be output from the audio reproducers  400 A,  400 B,  400 C the  400 D and the image reproducer at the same time. Owing to this, the versatility of the reproduction system  100  can be further increased.  
      Further, the present invention may be applied to such configuration that control signals as data, which are transmitted from a control signal transmitting device as data transmitting device, are output from the controller as the plurality of data output devices at the same time.  
      Each of the above-described functions is achieved as the programs. However, for example, the functions may be built in a piece of hardware such as a circuit board, or in one device such as IC (Integrated Circuit). Any mode of the configuration is available. When such configuration that the functions are read out from a programs or a separate recording medium is adopted, since they are easy to handle, the usage range thereof can be expanded easily.  
      Particular structures and steps for carrying out the present invention may be appropriately modified to another structure and the like within a range that the object of the present invention is achieved.  
     EFFECT OF EMBODIMENT  
      As described above, according to the above described embodiment, using the delay amount determiner  330 , the data transmitting device  300  in the reproduction system  100  performs the calculation as described below. That is, the delay time Da of the audio reproducer  400 A is calculated as, for example, 4 msec; the delay times Db and Dd of the audio reproducers  400 B and  400 D are calculated as, for example, 5 msec; and the delay time Dc of the audio reproducer  400 C is calculated as, for example, 3 msec. Then, the delay time information is generated at the delay information generator  350  based on the differential times Tz calculated from the delay times Dz. More specifically, the delay information generator  350  generates such delay time information, including information that requests on the audio reproducer  400 A to output the divided audio data SA 1  at the time when the predetermined time U and 1 msec, which is the differential time Ta, have passed from the time when the divided audio data SA 1  are acquired; information that request on the audio reproducers  400 B and  400 D to output the divided audio data SB 1  and SD 1  at the time when the predetermined time U and 0 msec, which is the differential times Th and Td, have passed from the time when the divided audio data SB 1  and SD 1  are acquired, i.e., at the time when the predetermined time U has passed from the time when the divided audio data SB 1  and SD 1  are acquired; and information that requests on the audio reproducer  400 C to output the divided audio data SC 1  at the time when the predetermined time U and 2 msec, which is the differential time Tc, have passed from the time when the divided audio data SC 1  are acquired. Then, the packet data  521 ,  531 ,  541  and  551  stored with the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , and the delay time information are transmitted to the audio reproducer set  400 .  
      Consequently, the audio reproducers  400 B and  400 D receive the packet data  531  and  551 , and the delay time information at the time when only 5 msec, which is the delay time Db and Dd, have passed from the frame output time. Then, the reproduction controller  433  outputs the divided audio data SB 1  and SD 1  from the data output section  432  at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Further, the audio reproducer  400 A receives the packet data  521  and the delay time information at the time when 4 msec, which is the delay time Da, has passed from the frame output time. Then, the reproduction controller  433  outputs the divided audio data SA 1  from the data output section  432  at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Further, the audio reproducer  400 C receives the packet data  541  and the delay time information at the time when 3 msec, which is the delay time Dc, has passed from the frame output time. Then, the reproduction controller  433  outputs the divided audio data SC 1  from the data output section  432  at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Accordingly, the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , which are the header portions of the audio data SA, SB, SC and SD, at the same time.  
      Further, the data transmitting device  300  can cause the audio reproducers  400 B and  400 D to receive the packet data  531  and  551 , and the delay time information at the time when only 5 msec, which is the delay time Db and Dd, have passed from the frame output time. Then, the divided audio data SB 1  and SD 1  can be transmitted to the audio reproducers  400 B and  400 D at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Further, the data transmitting device  300  can cause the audio reproducer  400 A to receive the packet data  521  and the delay time information at the time when only 4 msec, which is the delay time Da, has passed from the frame output time. Then, the divided audio data SA 1  can be transmitted to the audio reproducer  400 A at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Further, the data transmitting device  300  can cause the audio reproducer  400 C to receive the packet data  541  and the delay time information at the time when only 4 msec, which is the delay time Dc, has passed from the frame output time. Then, the divided audio data SC 1  can be output to the audio reproducer  400 C at the time based on the delay time information, i.e., at the time when the predetermined time U and 5 msec have elapsed from the frame output time. Accordingly, the data transmitting device  300  can cause the audio reproducers  400 A,  400 B,  400 C and  400 D to output the divided audio data SA 1 , SB 1 , SC 1  and SD 1 , which are the header portions of the audio data SA, SB, SC and SD, at the same time.  
      The priority application Number JP2003-367043 upon which this patent application is based is hereby incorporated by reference.