Patent Publication Number: US-2010121901-A1

Title: Moving-picture processing device and moving-picture processing method

Description:
This application is based upon and claims the benefit of priority from Japanese patent application No. 2008-287633, filed on Nov. 10, 2008, the disclosure of which is incorporated herein in its entirety by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a moving-picture processing device and a moving-picture processing method for distributing moving-picture data to an image-processing terminal. 
     2. Description of the Related Art 
     In recent years, portable telephones include functions for receiving the distribution of moving-picture data by way of radio communication and reproducing the received moving-picture data. Corresponding to these functions, a moving-picture distribution server that distributes moving-picture data converts moving-picture data to a format that can be reproduced on a portable telephone that is the distribution destination and distributes the result, as disclosed in Patent Document 1. The size and other attributes of moving-picture data that can be reproduced vary according to the type of portable telephone. As a result, a distribution server converts the format of the moving-picture data in accordance with the type of portable telephone. 
     Patent Document 1: JP-A-2004-222124 
     The moving-picture distribution server in the technology disclosed in the above-described Patent Document 1 fetches information about the portable telephone from the portable telephone and then converts moving-picture data such that appropriate reproduction is possible in that portable telephone. 
     This conversion of the moving-picture data takes time, and a delay is therefore produced from a request for the distribution of moving-picture data until the reproduction of the moving-picture data on the portable telephone. 
     This delay occurs not only when a portable telephone is used but can also occur in any information-processing terminal that receives the distribution of the moving-picture data. 
     This delay may cause a problem in which the user of an information-processing terminal will experience some dissatisfaction in viewing the moving-picture data that is distributed. 
     In addition, the radio communication state of the portable telephone may vary according to the state of movement or location of the user of the portable telephone. The problem therefore arises in which moving-picture data cannot be stably received and viewing of the moving-picture data is impeded. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a moving-picture processing device and a moving-picture processing method that can improve the degree of user satisfaction when viewing moving-picture data that are distributed. 
     To achieve the above-described object, the moving-picture processing device of the present invention includes: 
     a moving-picture processing unit subjecting moving-picture data to a distribution process for distributing the moving-picture data; 
     a distribution processing unit sequentially distributing, in portions of an arbitrary moving picture reproduction time to an information processing terminal that is connected by way of a network, the moving-picture data that have undergone the distribution process; and 
     a storage amount information acquisition unit acquiring from the information processing terminal storage amount information that indicates the storage amount of the pre-reproduction moving-picture data that have been stored in the information processing terminal; 
     wherein the moving-picture processing unit subjects the moving-picture data to the distribution process such that the reproduction quality of the moving-picture data changes according to a value indicated by the storage amount information. 
     In addition, the moving-picture processing method is a moving-picture processing method in a moving-picture processing device for distributing moving-picture data to an information processing terminal and includes: 
     a process of acquiring storage amount information that indicates the storage amount of the pre-reproduction moving-picture data that have been stored in the information processing terminal; 
     a moving-picture process of subjecting the moving-picture data to a distribution process for distributing the moving-picture data such that the reproduction quality of the moving-picture data changes according to a value indicated by the storage amount information; and 
     a process of sequentially distributing, in portions of an arbitrary moving picture reproduction time to an information processing terminal that is connected by way of a network, the moving-picture data that have undergone the distribution process. 
     According to the present invention, the moving-picture processing device includes: the moving-picture processing unit for subjecting moving-picture data to a distribution process for distributing the moving-picture data; the distribution processing unit for sequentially distributing, in portions of an arbitrary moving picture reproduction time to an information processing terminal that is connected by way of a network, the moving-picture data that have undergone the distribution process; and a storage amount information acquisition unit that acquires from the information processing terminal storage amount information that indicates the storage amount of pre-reproduction moving-picture data that have been stored in the information processing terminal. The moving-picture processing unit then subjects the moving-picture data to a distribution process such that the reproduction quality of the moving-picture data changes according to a value indicated by the storage amount information. 
     As a result, the degree of user satisfaction when viewing the distributed moving-picture data can be improved. 
     The above and other objects, features, and advantages of the present invention will become apparent from the following description with reference to the accompanying drawings, which illustrate examples of the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram for describing an outline of the moving-picture processing device of the present invention; 
         FIG. 2  is a block diagram showing an embodiment of the moving-picture distribution system in which the moving-picture processing device of the present invention is applied; 
         FIG. 3  is a block diagram showing an example of the configuration of portable telephone shown in  FIG. 2 ; 
         FIG. 4  is a block diagram showing an example of the configuration of the moving-picture distribution server shown in  FIG. 2 ; 
         FIG. 5  is a view for explaining the state of distribution of moving-picture data in the moving-picture distribution system shown in  FIG. 2 ; 
         FIG. 6  is a view for explaining the state of distribution of moving-picture data in the moving-picture distribution system shown in  FIG. 2 ; 
         FIG. 7  is a view for explaining the state of distribution of moving-picture data in the moving-picture distribution system shown in  FIG. 2 ; 
         FIG. 8  is a view for explaining the state of distribution of moving-picture data in the moving-picture distribution system shown in  FIG. 2 ; 
         FIG. 9  shows the relation between the reproduction quality of moving-picture data that portable telephone receives and the storage amount of pre-reproduction moving-picture data that are stored in portable telephone  10  shown in  FIGS. 2 and 3 ; and 
         FIG. 10  is a sequence chart for explaining the operations of the moving-picture distribution system shown in  FIGS. 2-9 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of the present invention are next described with reference to the accompanying figures. 
     An outline of the moving-picture processing device of the present invention is first described. 
       FIG. 1  is a block diagram for explaining an outline of the moving-picture processing device of the present invention. 
     As shown in  FIG. 1 , moving-picture processing device  1  is provided with: storage amount information acquisition unit  2 , moving-picture processing unit  3 , and distribution processing unit  4 . 
     Storage amount information acquisition unit  2  fetches from information processing terminal  6  storage amount information that indicates the amount of pre-reproduction moving-picture data that are stored in information processing terminal  6 . 
     Based on the storage amount information that was fetched by storage amount information acquisition unit  2 , moving-picture processing unit  3  subjects moving-picture data  5  to a distribution process such that the reproduction quality of moving-picture data  5  changes. The distribution process is a process for distributing moving-picture data and is a process implemented upon moving-picture data according to the distribution destination of the moving-picture data. 
     Distribution processing unit  4  sequentially distributes, in portions of an arbitrary moving picture reproduction time to information processing terminal  6  that is connected by way of network N, moving-picture data that have undergone the distribution process. 
     This completes the outline of the moving-picture processing device of the present invention. 
       FIG. 2  is a block diagram showing an embodiment of the moving-picture distribution system in which the moving-picture processing device of the present invention is applied. 
     In the present embodiment, a portable telephone is offered as an example of the information processing terminal that is the distribution destination of moving-picture data. However, the information processing terminal that is the distribution destination of moving-picture data is not limited to a portable telephone, and further, is not limited to an information processing terminal that receives the distribution of moving-picture data by way of a wireless communication network. Essentially, the information processing terminal that is the distribution destination may be any kind of information processing terminal, and may be, for example, a personal computer that is connected by way of a cable network. 
     (Overall Configuration) 
     As shown in  FIG. 2 , the moving-picture distribution system of the present embodiment is provided with: portable telephone  10  that is manipulated by a user that views moving-picture data; moving-picture distribution server  20  that is the moving-picture processing device; and content server  30  that stores moving-picture data. 
     Content server  30  and moving-picture distribution server  20  are each connected by way of network N 1  such as an Internet network. Portable telephone  10  is connected to moving-picture distribution server  20  by way of network N 1  such as an Internet network or a portable telephone network and wireless communication network N 2 . 
     (Configuration of Portable Telephone) 
       FIG. 3  is a block diagram showing an example of the configuration of portable telephone  10  shown in  FIG. 2 . 
     Portable telephone  10  in the present embodiment is a typical portable telephone that is provided with an arithmetic unit, a memory unit, a communication unit, a console unit and a display device; and the communication capability is of course provided with a data communication capability. Portable telephone  10  is provided with the capability to reproduce moving-picture data that are distributed from a server computer on a network. Explanation of the basic functions of portable telephone  10  is here omitted. 
     As shown in  FIG. 3 , portable telephone  10  shown in  FIG. 2  is provided with: distribution request unit  11 , moving-picture reception unit  12 , and moving-picture reproduction unit  13  that are created by the installation of a program in a CPU (not shown) that is the arithmetic unit; and with memory  14 . 
     Distribution request unit  11  transmits a distribution request to moving-picture distribution server  20 . The distribution request is a command for requesting the distribution of moving-picture data that the user wishes to view. The distribution request includes content-specifying information for identifying the content, i.e., moving-picture data. The content-specifying information is generated by, for example, accessing a website that is established by moving-picture distribution server  20  from portable telephone  10  and then selecting the content that is to be viewed from among a list of content that is displayed on the website. The distribution request further includes terminal information. The terminal information is information indicating the specifications of the portable telephone  10 , and for example, is model information indicating the model of portable telephone  10  or format information that indicates the format of moving-picture data that can be reproduced on portable telephone  10 . The terminal information is stored in advance in memory  14 . Distribution request unit  11  reads the terminal information that is stored in memory  14 , includes the terminal information that has been read together with the content-specifying information in a distribution request and transmits it to moving-picture distribution server  20 . Distribution request unit  11  further transmits to moving-picture distribution server  20  storage amount information that indicates the amount of pre-reproduction moving-picture data that are stored in memory  14  of portable telephone  10 . This storage amount information is, for example, transmitted when transmitting a distribution request or, as will be explained hereinbelow, at fixed time intervals or at a timing that is determined in advance during reproduction of moving-picture data. In addition, distribution request unit  11  further transmits to moving-picture distribution server  20  together with storage amount information state-of-use information, which indicates the state of use of resources that are provided in portable telephone  10  such as the memory or CPU, and resource information, which includes maximum values of the performance of resources such as the memory or CPU. Resource information is stored in advance in memory  14 . 
     Moving-picture reception unit  12  receives moving-picture data that are distributed from moving-picture distribution server  20  and stores the moving-picture data in memory  14 . At this time, moving-picture data of an arbitrary reproduction time are sequentially distributed from moving-picture distribution server  20 , and moving-picture reception unit  12  sequentially receives these data. 
     Moving-picture reproduction unit  13  reproduces moving-picture data that are stored in memory  14 , and the user of portable telephone  10  is thus able to view the moving-picture data. Moving-picture data for which reproduction has been completed are sequentially discarded. 
     (Configuration of the Moving-Picture Distribution Server) 
       FIG. 4  is a block diagram showing an example of the configuration of moving-picture distribution server  20  shown in  FIG. 2 . Moving-picture distribution server  20  is a typical server computer that is provided with an arithmetic unit, a memory unit, and a communication unit. 
     As shown in  FIG. 4 , moving-picture distribution server  20  shown in  FIG. 2  is provided with: distribution request acceptance unit  21  that is the storage amount information acquisition unit and resource information acquisition unit; content acquisition unit  22 , moving-picture processing unit  23 , and distribution processing unit  24  that are created by installation of a program in a CPU, i.e., the arithmetic unit. 
     Distribution request acceptance unit  21  receives a distribution request that is transmitted from portable telephone  10 . Distribution request acceptance unit  21  then issues a request to content server  30  for content that is specified by the content-specifying information contained in the distribution request that was received. At this time, distribution request acceptance unit  21  receives the above-described storage amount information and resource information together with the distribution request that was transmitted from portable telephone  10  and supplies the storage amount information and resource information to moving-picture processing unit  23  and distribution processing unit  24 . Distribution request acceptance unit  21  further receives storage amount information and resource information that were transmitted from portable telephone  10  at times other than when receiving a distribution request, and supplies the storage amount information and resource information that were received to moving-picture processing unit  23  and distribution processing unit  24 . In this way, moving-picture distribution server  20  is always able to recognize the current state of portable telephone  10 . 
     Content acquisition unit  22  receives moving-picture data that are the content transmitted from content server  30 . Content server  30  stores, for example, moving-picture data having a predetermined data amount at the time of reproduction. These moving-picture data are stored in any format. Of the moving-picture data that are stored, content server  30  transmits the moving-picture data that correspond to the requested content to moving-picture distribution server  20  in accordance with the time sequence of the reproduction time of the moving-picture data. Content acquisition unit  22  then sequentially supplies the moving-picture data that were received to moving-picture processing unit  23 . 
     Moving-picture processing unit  23  subjects the moving-picture data that were supplied from content acquisition unit  22  to the distribution process. As an example of the distribution process at this time, moving-picture processing unit  23  converts the moving-picture data to a format that corresponds to portable telephone  10  based on model information or format information of moving pictures that can be reproduced that was transmitted from portable telephone  10 . Alternatively, moving-picture processing unit  23  subjects the moving-picture data to a distribution process such that the reproduction quality of the moving-picture data varies according to the storage amount information or resource information that was supplied from distribution request acceptance unit  21 . Moving-picture processing unit  23  then supplies the moving-picture data that have undergone the distribution process to distribution processing unit  24 . 
     Distribution processing unit  24  receives the moving-picture data that have undergone the distribution process and that were supplied from moving-picture processing unit  23 . Distribution processing unit  24  then distributes the moving-picture data that were received to portable telephone  10 . Distribution processing unit  24  sequentially distributes moving-picture data in portions of an arbitrary moving picture reproduction time, and the data volume that is distributed each time may be a fixed value that was determined in advance, or may vary according to storage amount information or resource information that was supplied from distribution request acceptance unit  21 . 
     The operations of moving-picture processing unit  23  and distribution processing unit  24  will next be described in detail. 
     First, moving-picture processing unit  23  changes the reproduction quality of the moving-picture data by changing the data amount per unit time during reproduction of the moving-picture data according to the size of the value indicated by the storage amount information. For example, the smaller the value indicated by the storage amount information (the smaller the storage amount), the lower moving-picture processing unit  23  sets the reproduction quality of the moving-picture data with the aim of enabling continuous reproduction of moving-picture data in portable telephone  10 . In this way, moving-picture data for distribution that have a small data amount are generated. Then, when the value indicated by the storage amount information is no greater than a minimum value that was determined in advance, distribution processing unit  24  distributes the moving-picture data in bursts of a short reproduction time. In other words, moving-picture data of a small data amount are distributed. However, when the value indicated by the storage amount information is small but exceeds a minimum value that was determined in advance, distribution processing unit  24  distributes the moving-picture data in bursts of a longer reproduction time. 
     On the other hand, the larger the value indicated by the storage amount information (the greater the storage amount), the higher the moving-picture processing unit  23  sets the reproduction quality to generate moving-picture data. Accordingly, distribution processing unit  24  distributes moving-picture data in bursts of a short reproduction time such that the time period of receiving moving-picture data by portable telephone  10  does not become excessively long. 
       FIGS. 5-8  are figures for explaining the state of distribution of moving-picture data in the moving-picture distribution system shown in  FIG. 2 , (a) and (b) both indicating pre-reproduction moving-picture data that are stored in memory  14  provided in portable telephone  10 . 
       FIG. 9  is a view showing the relation between the storage amount of pre-reproduction moving-picture data that are stored in portable telephone  10  shown in  FIGS. 2 and 3  and the reproduction quality of the moving-picture data that are received by portable telephone  10 . 
     First,  FIG. 5(   a ) shows the state of memory  14  at the time of the start of distribution of moving-picture data by moving-picture distribution server  20 . At this point in time, moving-picture data are not stored in memory  14 , and portable telephone  10  transmits to moving-picture distribution server  20  storage amount information that indicates that the storage amount is “0” together with a distribution request. 
     In this case, as shown in  FIG. 5(   b ), moving-picture processing unit  23  of moving-picture distribution server  20  generates low-bit-rate (low image quality) moving-picture data  50  that are moving-picture data of the minimum bit rate that allows viewing of the moving-picture data when the moving-picture data are reproduced in portable telephone  10 . Distribution processing unit  24  then distributes to portable telephone  10  low-bit-rate moving-picture data  50  having the minimum reproduction time required for reproduction of the moving-picture data on portable telephone  10 . In  FIG. 5  and in the zone shown by “initial state” in  FIG. 9 , the image quality of distributed moving-picture data  51  that are distributed is of the minimum image quality, and for example, moving-picture data in portions of a two-second reproduction time are sequentially distributed to portable telephone  10 . In this case, moving-picture data having a small data amount that are of low image quality and short reproduction time portions are sequentially distributed and stored in portable telephone  10 . As a result, reproduction can begin quickly. 
       FIG. 5(   b ) shows the state in which moving-picture data are steadily stored in memory  14  and reproduction is continued. In  FIG. 5(   b ), data amount  40  indicates the amount of data of moving-picture data that are stored in memory  14 . In addition, output data  55  indicates, from among the moving-picture data that are stored in memory  14 , the moving-picture data that are supplied for reproduction. During this period as well, distribution request acceptance unit  21  of moving-picture distribution server  20  periodically receives storage amount information that is transmitted from portable telephone  10 . 
     When the storage amount information transmitted from portable telephone  10  subsequently surpasses the minimum value that was determined in advance, the “buffer-priority state” shown in  FIG. 9  results. In this case, although the image quality is low, moving-picture processing unit  23  and distribution processing unit  24  carry out distribution that prioritizes storage of the moving-picture data in memory  14 . 
       FIG. 6(   a ) shows the state when moving-picture data of minimum value  41  that was determined in advance are stored in memory  14 . Because there is a certain storage amount, moving-picture processing unit  23  generates low-bit-rate moving-picture data  50  in which the reproduction quality is slightly increased. Distribution processing unit  24  then distributes distributed moving-picture data  51  in portions of reproduction time that are somewhat longer time than in the initial state. Thus, as shown in  FIG. 6(   b ), although there are output data  55  supplied for reproduction from memory  14 , moving-picture data having a data amount that exceeds this are distributed to portable telephone  10 . As a result, the storage amount of moving-picture data in memory  14  increases. In addition, the image quality of the moving-picture data can be raised, although only by a slight degree. 
     When the storage amount information reported from portable telephone  10  exceeds an intermediate value that has been determined in advance, the “intermediate state” shown in  FIG. 9  results, and moving-picture processing unit  23  and distribution processing unit  24  implement distribution of moving-picture data that takes into consideration the increase of the storage amount of the moving-picture data in memory  14  while raising the image quality. 
       FIG. 7(   a ) shows the state when moving-picture data of intermediate value  42  that is determined in advance are stored in memory  14 . Due to this storage amount, moving-picture processing unit  23  generates medium-bit-rate moving-picture data  52  which are moving-picture data of medium image quality in which the reproduction quality is further increased over the previous image quality. Distribution processing unit  24  then distributes distributed moving-picture data  51  in bursts of a reproduction time that is shorter time than during the buffer-priority state but that is equivalent to or longer than the actual reproduction time. In this way, as shown in  FIG. 7(   b ), although there are output data  55  that are supplied by reproduction from memory  14 , moving-picture data having an equal or greater data amount are distributed to portable telephone  10 . As a result, the storage amount of moving-picture data in memory  14  further increases, although only by small degrees. In addition, the image quality of the moving-picture data can be further increased. 
     When the storage amount information reported from portable telephone  10  surpasses a high storage value that is determined in advance, the “semi-steady state” or “steady state” shown in  FIG. 9  results, and moving-picture processing unit  23  and distribution processing unit  24  distribute moving-picture data such that the storage amount of moving-picture data to memory  14  does not decrease while further increasing the image quality. 
       FIG. 8(   a ) shows the state when moving-picture data having high storage value  43  that is determined in advance are stored in memory  14 . Due to this ample storage amount, moving-picture processing unit  23  generates high-bit-rate moving-picture data  53  that are moving-picture data of high quality in which the reproduction quality has been further increased over previous image quality. Distribution processing unit  24  distributes distributed moving-picture data  51  in bursts of reproduction time that is shorter time than the intermediate state but that is equivalent to or longer than the actual reproduction time. In this way, as shown in  FIG. 8(   b ), although there are output data  55  that are supplied as output due to reproduction from memory  14 , moving-picture data having an equivalent or greater data amount are distributed to portable telephone  10 . As a result, the storage amount of moving-picture data in memory  14  is uniformly maintained without reduction. In addition, the image quality of the moving-picture data can be further increased. 
     In addition, moving-picture processing unit  23  and distribution processing unit  24  change the data amount that is distributed or the distribution process of moving-picture data according to, in addition to the storage amount information to memory  14  of portable telephone  10 , resource information that is reported from portable telephone  10 . For example, when the state of use of the CPU is close to the maximum, moving-picture processing unit  23  implements a distribution process that instead of setting the quality of moving-picture data to still higher quality, keeps the quality of moving-picture data uniform or reduces the quality such that the state of use of the CPU due to moving-picture data that are delivered does not reach the maximum. In addition, even when the state of use of memory  14  approaches a maximum, moving-picture processing unit  23  implements the distribution process such that, instead of setting the quality of moving-picture data to still higher quality, keeps the quality uniform or reduces the quality such that the state of use of memory  14  does not reach the maximum. Alternatively, distribution processing unit  24  limits the data amount that is distributed or vacates the spacing of distributing moving-picture data to distribute moving-picture data in portions of a short reproduction time. In this way, the load at portable telephone  10  can be limited and the reproduction of moving-picture data optimized. As a result, the degree of user satisfaction when viewing moving-picture data that have been distributed can be improved. 
     (Operation) 
     The operations of the moving-picture distribution system that is configured as described above are next described. 
       FIG. 10  is a sequence chart for explaining the operations of the moving-picture distribution system shown in  FIGS. 2-9 . 
     The user of portable telephone  10  first, by manipulating portable telephone  10 , accesses a website that is established by moving-picture distribution server  20  and selects content on the website that the user wishes to view. 
     In Step  51 , distribution request unit  11  of portable telephone  10  next transmits to moving-picture distribution server  20  a distribution request that includes content-specifying information and, for example, model information or format information. At this time, distribution request unit  11  transmits to moving-picture distribution server  20  storage amount information and resource information together with the distribution request. 
     Distribution request acceptance unit  21  of moving-picture distribution server  20  receives the storage amount information and resource information together with the distribution request that was transmitted from portable telephone  10 . 
     In Step S 2 , distribution request acceptance unit  21  next issues a request to content server  30  for the content that is specified by the content-specifying information that was contained in the received distribution request. 
     Distribution request acceptance unit  21  supplies the received storage amount information and resource information to moving-picture processing unit  23  and distribution processing unit  24 . 
     In Step S 3 , content server  30  next, in accordance with the request from moving-picture distribution server  20 , reads the moving-picture data that are the requested content from the database that stores various content and transmits the moving-picture data to moving-picture distribution server  20 . 
     In Step S 4 , content acquisition unit  22  of moving-picture distribution server  20  receives the moving-picture data that were sequentially transmitted from content server  30   
     Content acquisition unit  22  then supplies the received moving-picture data to moving-picture processing unit  23 . 
     Moving-picture processing unit  23  receives the moving-picture data that were supplied from content acquisition unit  22  and the storage amount information and resource information that were supplied from distribution request acceptance unit  21 . 
     In Step S 5 , moving-picture processing unit  23  next subjects the received moving-picture data to the distribution process. Here, moving-picture processing unit  23  converts the moving-picture data to a format based on, for example, the model information or format information that was contained in the distribution request transmitted from portable telephone  10 . Moving-picture processing unit  23  further changes the reproduction quality of the moving-picture data according to the storage amount information or resource information that was supplied from distribution request acceptance unit  21 . 
     More specifically, at the time of starting distribution of moving-picture data, the storage amount of moving-picture data that are stored in memory  14  of portable telephone  10  is “0.” As a result, moving-picture processing unit  23  generates low-bit-rate moving-picture data  50  that is the minimum that can be viewed when reproduced on portable telephone  10 . 
     Moving-picture processing unit  23  then supplies moving-picture data  50  that have been generated to distribution processing unit  24 . 
     Distribution processing unit  24  receives moving-picture data  50  that were supplied from moving-picture processing unit  23 . 
     In Step S 6 , distribution processing unit  24  distributes to portable telephone  10 , of moving-picture data  50  that were received, moving-picture data of reproduction time that is equal to or greater than the minimum time necessary for reproduction on portable telephone  10 . For example, moving-picture data that are of the minimum low-image quality, and moreover, that are arranged in portions on the order of one- or two-second reproduction time are sequentially distributed to portable telephone  10 . 
     Moving-picture reception unit  12  of portable telephone  10  receives the moving-picture data that were distributed from moving-picture distribution server  20  and supplies the received moving-picture data to memory  14 . 
     In Step S 7 , moving-picture reproduction unit  13  reproduces the moving-picture data that were stored in memory  14 , thus allowing the user of portable telephone  10  to view moving-picture data of the requested content. 
     In this way, moving-picture data that are of the minimum low-image quality, and moreover, that are in portions of a short reproduction time are distributed to portable telephone  10  in the initial state shown in  FIG. 9 . As a result, moving-picture data of low image quality are quickly stored in portable telephone  10 . As a result, moving pictures can be viewed without delay. 
     Subsequently, while the reception and reproduction of moving-picture data is continued, distribution request unit  11  of portable telephone  10  in Step S 8  transmits to moving-picture distribution server  20  storage amount information at fixed time intervals or at a timing that is determined in advance. At this time, distribution request unit  11  also transmits resource information together with the storage amount information to moving-picture distribution server  20 . 
     Distribution request acceptance unit  21  of moving-picture distribution server  20  receives the storage amount information and resource information that were transmitted from portable telephone  10 . 
     Distribution request acceptance unit  21  next supplies the storage amount information and resource information that were received to moving-picture processing unit  23  and distribution processing unit  24 . 
     Moving-picture processing unit  23  receives the storage amount information and resource information that were supplied from distribution request acceptance unit  21 , and in Step S 9 , generates moving-picture data in which the image quality is changed according to the received storage amount information and resource information. 
     Moving-picture processing unit  23  supplies the moving-picture data that were generated to distribution processing unit  24 . 
     Distribution processing unit  24  that has received the storage amount information and resource information that were supplied from distribution request acceptance unit  21  and the moving-picture data that were supplied from moving-picture processing unit  23  changes the data amount according to the received storage amount information and resource information and distributes moving-picture data to portable telephone  10  in Step S 10 . 
     The above-described operations from Step S 8  to Step S 11  are repeated. More specifically, when the storage amount information that was reported from portable telephone  10  surpasses minimum value  41  that was determined in advance, the “buffer-priority state” shown in  FIG. 9  results. In this case, moving-picture distribution server  20  distributes moving-picture data while prioritizing storage of moving-picture data to memory  14 , although the moving-picture data are of low image quality. For example, moving-picture distribution server  20  generates moving-picture data that, while of low image quality, have reproduction quality that is slightly increased over that of the above-described initial state. In addition, moving-picture data are distributed in bursts of a reproduction time that is even longer than the initial state. As a result, not only can the image quality of the moving-picture data be raised, but the storage amount of moving-picture data in memory  14  can also be increased. 
     When the storage amount information reported from portable telephone  10  surpasses intermediate value  42  that is determined in advance, the “intermediate state” shown in  FIG. 9  results. In this case, moving-picture distribution server  20  distributes moving-picture data while taking into consideration increase of the storage amount of moving-picture data to memory  14  while also raising the image quality. For example, when there is a certain storage amount, moving-picture data of the intermediate image quality in which the reproduction quality is further increased are generated. Moving-picture data are distributed in bursts of a reproduction time that is shorter than in the buffer-priority state but that is equal to or greater than the actual reproduction time. In this way, the storage amount of moving-picture data in memory  14  can be increased a little at a time while the image quality of moving-picture data is increased. 
     When the value indicated by the storage amount information that is transmitted from portable telephone  10  subsequently surpasses high storage value  43  that is determined in advance, the “semi-steady state” or “steady state” shown in  FIG. 9  results. In this case, moving-picture distribution server  20 , while raising the image quality, distributes moving-picture data such that the storage amount of moving-picture data to memory  14  does not diminish. For example, when the storage amount is ample, moving-picture distribution server  20  generates moving-picture data of high image quality in which the reproduction quality is increased over previous levels. Moving-picture data are then distributed in bursts of a reproduction time that, although shorter than during the intermediate state, is equivalent or greater than the actual reproduction time. In this way, moving-picture distribution server  20  can suppress a decrease of the storage amount of moving-picture data in memory  14  to keep the storage amount uniform while further raising the image quality of moving-picture data. 
     In this way, moving-picture distribution server  20  in the present embodiment includes: moving-picture processing unit  23  for subjecting moving-picture data to a distribution process for distributing the moving-picture data; distribution processing unit  24  for sequentially distributing, in portions of an arbitrary moving picture reproduction time to portable telephone  10  that is connected by way of a network, the moving-picture data that have undergone the distribution process; and distribution request acceptance unit  21  for fetching from portable telephone  10  storage amount information that indicates a storage amount of pre-reproduction moving-picture data that have been stored in portable telephone  10 . Moving-picture processing unit  23  then subjects the moving-picture data to the distribution process such that the reproduction quality of the moving-picture data changes according to the value that is indicated by the storage amount information. 
     For example, when the value indicated by the storage amount information is “0,” moving-picture data of low image quality and of a small data amount are distributed in portions of a reproduction time of short duration to enable a quick start of reproduction. When moving-picture data that have not been reproduced are stored in portable telephone  10 , moving-picture data are generated for distribution in which the image quality is low and the data amount is limited to distribute moving-picture data in bursts of a longer reproduction time. In other words, moving-picture processing unit  23  subjects the moving-picture data to a distribution process such that the smaller the value indicated by the storage amount information (the lower the storage amount), the lower the reproduction quality of the moving-picture data. In this way, the storage amount of moving-picture data can be increased while ensuring continuous reproduction in portable telephone  10 . 
     On the other hand, when the value indicated by the storage amount information becomes large (ample storage amount), moving-picture data of even higher image quality are generated to distribute moving-picture data in bursts of a short reproduction time. In other words, moving-picture processing unit  23  subjects moving-picture data to a distribution process such that the greater the value indicated by the storage amount information (the greater the storage amount), the higher the reproduction quality of the moving-picture data. In this way, higher picture quality can be achieved in portable telephone  10  while limiting a decrease in the storage amount of moving-picture data to ensure continuous reproduction. 
     Accordingly, according to the state of portable telephone  10 , higher image quality of moving-picture data can be achieved while ensuring continuous reproduction. As a result, the degree of user satisfaction when viewing moving-picture data that are distributed can be improved. 
     Finally, moving-picture distribution server  20  in the present embodiment is not necessarily made up from a single information processing device, and each of the functions provided in moving-picture distribution server  20  may be provided by being dispersed among a multiplicity of information processing devices. 
     While the invention has been particularly shown and described with reference to exemplary embodiments thereof, the invention is not limited to these embodiments. It will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined in the claims.