JPWO2008108379A1 - MEDIA DISTRIBUTION SYSTEM, DISTRIBUTION SERVER DEVICE, MEDIA DISTRIBUTION METHOD USED FOR THEM, AND PROGRAM THEREOF - Google Patents

Abstract

In the distribution server 1, the terminal information acquisition unit 11 acquires the terminal information of the receiving terminal 5, and the terminal performance determination unit 13 compares the terminal information with the terminal database 12 to determine the terminal performance of the receiving terminal 5. The connection environment discriminating means 15 discriminates the connection environment of the receiving terminal 5, and the band fluctuation predicting means 17 predicts future band fluctuation for a certain period from the connection environment and the current band obtained by the band measuring means 16. The bit rate determining means 18 determines the optimum bit rate of high-quality media to be delivered to the receiving terminal 5 based on the predicted bandwidth fluctuation and the resources available to the receiving terminal 5 obtained by the terminal resource acquiring means 14. Then, the encoding means 19 selects an optimal encoding method.

Description

  The present invention relates to a media distribution system, a distribution server device, a media distribution method used therefor, and a program thereof, and more particularly to a system for distributing media such as video and music to a personal computer or a portable information terminal.

In recent years, with the above-mentioned systems, the need for browsing large-capacity video and music over the network has increased along with the broadband network and the high performance of personal computers (hereinafter referred to as personal computers) and personal digital assistants. Services that distribute video and music to meet these needs have begun. As this service, there are a file download format and a streaming format for sequential distribution. Here, a streaming format that does not require a large-capacity storage for storing the downloaded media on the receiving side is targeted.
Many services that deliver media in streaming format provide data with different bit rates in accordance with the user's communication environment. On the other hand, in an open network environment such as the Internet or in an environment where there is a large change in the physical environment such as a wireless LAN (Local Area Network), the communication band varies, so the average bandwidth exceeds the bit rate specified by the user. However, depending on the timing, the bit rate specified by the user may be significantly lower.
In such a case, many services require extra time to receive media, so the user may wait until the required amount of media has been downloaded, or some media may be lost and interrupted. To do. In some cases, the connection may need to be restarted from the beginning.
As a method for changing the bit rate by controlling the quality of the media in accordance with such a band variation, JP 2002-204278 A, JP 2002-209554 A, JP 2002-325095 A, JP JP 2004-015429 A, JP 2004-214755 A, JP 2004-222044 A, JP 2004-272563 A, JP 2004-357226 A, JP 2005-286978 A, JP 2005-2005 A. A method described in Japanese Patent No. 318057 (hereinafter referred to as documents 1 to 10 in order) has been proposed. Further, as a method for predicting not only the current bandwidth but also the future bandwidth, a method described in Japanese Patent Laid-Open No. 2005-151352 (hereinafter referred to as Literature 11) has been proposed. Further, although tracking of bandwidth fluctuation is not mentioned, a method described in Japanese Patent Laid-Open No. 2001-128132 (hereinafter referred to as Document 12) has been proposed as a method for reducing the amount of image data.
In addition to these, as a method for controlling a communication session in accordance with a band, a method described in Japanese Patent Application Laid-Open No. 2005-157323 (hereinafter referred to as Document 13) has been proposed. This is a circuit that controls line allocation so that bandwidth is allocated as evenly as possible regardless of the communication contents of each communication terminal when there is a terminal. The field of application and purpose differ from the invention.
In addition to the above, as a method for deferring data when there is a margin in the bandwidth, a method described in Japanese Patent Laid-Open No. 2003-209593 (hereinafter referred to as Document 14) has been proposed. The purpose of the present invention differs from the present invention in which media is transmitted at an optimum bit rate in accordance with the variation of the communication band.
In addition to the above, as a method for adjusting the capacity of a moving image, a method described in Japanese Patent Laid-Open No. 11-136673 (hereinafter referred to as Document 15) has been proposed. For example, the present invention for transmitting media at an optimum bit rate in accordance with fluctuations in the communication band also has an application field. The purpose is also different.

In the conventional techniques described above, the communication bandwidths are measured in the methods described in the above documents 1 to 10, but it is only possible to know the bandwidth before the portion is distributed for a specific portion of the media. It is. Therefore, these methods cannot cope with a case where the band fluctuates between the band measurement and the actual transmission. In particular, in the case of mobile communication, since the band fluctuation is significant, the measured band may be greatly different from the band at the time of actual data transmission.
Further, according to the methods described in these documents 1 to 10, the bit rate is adjusted so as to fit the band at the time of measurement, or an appropriate bit rate is estimated from the average of the band over a certain period. However, when the bit rate is adjusted so as to fit the measured bandwidth, if the bandwidth changes frequently and the media quality frequently changes, viewing will be disturbed. Since the average of the band for a certain period is only the average of the past, the divergence may increase when applied to the future.
For example, in Document 1, the future bandwidth prediction is not performed, only the current bandwidth is used, and the bit rate is changed after jitter or packet loss once occurs. May be significantly reduced. In addition, it is a technique that depends on a specific communication protocol called RTP (Real Time Transport Protocol), and it may be difficult to apply to other protocols.
Also in image coding, the specific description of the bit rate change is simply a change of the GOP (Group Of Pictures) interval of the moving image, and there are narrow trade-off options for media quality and bit rate, and low bit rate. It is difficult to achieve high quality at a rate. Further, in the above-mentioned document 1, since the GOP interval is used, it cannot be applied to audio-only media.
In Reference 12, the same amount of video data is reduced by omitting key frames corresponding to GOP. However, it is difficult to achieve high quality at a low bit rate. It is invalid.
Reference 15 also provides a specific example of adjusting the amount of data, which is GOP interval adjustment. Like the above, it is difficult to achieve high quality at a low bit rate, and is invalid for audio-only data. It is.
Similarly, for example, even in Document 4, since the future bandwidth prediction is not performed, only the current bandwidth is used, and the packet rate may change once the packet loss occurs. There is a possibility of a significant temporary decrease. Further, even if packet loss does not occur, Document 4 does not assume a case where the bandwidth fluctuates rapidly. Therefore, the bit rate suddenly fluctuates when the bandwidth fluctuates rapidly, resulting in a decrease in media quality. There is a case. In addition, as a feature of this method, in the band search mode, the transmission bit rate is changed without changing the content bit rate, but the media length (length) does not match the transmission time, so it is frequently optimal. If an attempt is made to find a suitable bit rate, the reproduction will be delayed and the quality of the media will deteriorate.
Similarly, for example, also in Document 5, future band prediction is not performed, and only the current band is used. Document 5 aims at continuous reproduction, and when the bandwidth changes rapidly, the quality of the media also changes rapidly.
Further, for example, in Literature 3, the average of the past band is used as the predicted value, but the deviation from the actual fluctuation may be large.
Further, in Document 3, since the band is changed after the jitter is measured, if the delay is large and abrupt band fluctuation occurs, the bit rate cannot be changed and the quality of the media may be significantly lowered. In addition, Document 3 assumes a specific communication protocol called RTP, which may be difficult to apply to other protocols.
In the above method, if it takes time to convert media, it can be made in time if it is converted in advance. However, these proposed methods only know the current bandwidth. It is necessary to prepare bit rate media. Therefore, a large-capacity storage is required, and the conversion time becomes long.
On the other hand, in Reference 11, the band at a certain point in the future is predicted, but the position of the vehicle at a certain point in the future is estimated from the position and speed of the vehicle assumed as the receiving terminal. Because the band is only predicted from the reception status at that location, it is not possible to cope with changes in physical conditions such as weather conditions and electromagnetic environment, bandwidth occupancy due to use by other users, etc. .
Reference 11 aims to reduce the interruption of the media, but does not assume a case where the bandwidth fluctuates rapidly. Therefore, when the bandwidth fluctuates rapidly, the quality of the media also fluctuates abruptly. End up.
When changing the bit rate of a moving image by the method described in the above-mentioned documents 1 to 12, it is assumed that encoding is performed simply by specifying the bit rate. If the bit rate is small, block noise, etc. It may become low quality that is hard to watch.
In addition, none of these methods change the bit rate assuming the usage status of the receiving terminal and the capability of the receiving terminal, and the specifications vary depending on the model, such as a mobile phone or PDA (Personal Digital Assistant). If this is a receiving terminal, media that cannot be reproduced may be transmitted to the receiving terminal.
Therefore, the object of the present invention is to solve the above-mentioned problems, and even in an environment where the band frequently fluctuates, it is possible to stably distribute the media quality as long as the user does not feel uncomfortable or unnatural. It is to provide a media distribution system, a distribution server device, a media distribution method used for them, and a program thereof.

A media distribution system according to an aspect of the present invention includes a distribution server that distributes media including at least video and music, and a receiving terminal that receives and reproduces the media from the distribution server via a network. Because
The distribution server includes a terminal information acquisition unit that acquires terminal information indicating a model of the receiving terminal, a terminal database that stores the terminal information in advance, terminal information acquired by the terminal information acquisition unit, and a terminal of the terminal database Terminal performance discrimination means for collating information to determine the processing capability of the receiving terminal and the corresponding media format as terminal performance, the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity. A terminal resource acquisition unit that acquires at least a resource that includes the resource as an available resource, a connection environment determination unit that determines an environment type to which the receiving terminal is connected, as a connection environment, a band measurement unit that measures a current band, and a connection Predicts future bandwidth fluctuations for a predetermined period of time based on the type of environment used and the current available bandwidth The bandwidth fluctuation prediction means for making the future bandwidth fluctuation, the terminal performance, the available resources, and the future bandwidth fluctuation, even if the bandwidth suddenly fluctuates, the receiving terminal does not interrupt the media and the quality of the media is high. A bit rate determining means for determining an optimum bit rate of the media that does not change rapidly in the future while maintaining quality, and an optimum encoding method for achieving the optimum bit rate is selected and Encoding means for encoding media, and distribution means for distributing the encoded media to the receiving terminal,
The receiving terminal uses a buffering means for storing the media in a buffer for a predetermined time, a playback means for playing back the stored media, and resources currently available from the buffering means and the playback means. Terminal resource notifying means for acquiring as a possible resource and notifying the distribution server.
A distribution server device according to another aspect of the present invention is a distribution server device that distributes media including at least video and music to a receiving terminal via a network.
A terminal information acquisition unit that acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, a terminal information acquired by the terminal information acquisition unit, and a terminal information in the terminal database are collated. Terminal performance determining means for determining the processing capability and corresponding media format of the receiving terminal as terminal performance, and using resources including at least the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity A terminal resource acquisition unit that acquires as a possible resource, a connection environment determination unit that determines an environment type to which the receiving terminal is connected, as a connection environment, a band measurement unit that measures a current band, and a connected environment type Predicts future bandwidth fluctuations for a predetermined period from the current available bandwidth and The bandwidth fluctuation prediction means, the terminal performance, the available resources, and the future bandwidth fluctuation, even if the bandwidth suddenly fluctuates, the media is not interrupted at the receiving terminal and the quality of the media is maintained high. A bit rate determining means for determining an optimal bit rate of the medium that does not change rapidly in the future, and an optimal encoding method for achieving the optimal bit rate is selected to encode the medium. An encoding unit; and a distribution unit that distributes the encoded medium to the receiving terminal.
A media distribution method according to another aspect of the present invention includes a distribution server that distributes media including at least video and music, and a receiving terminal that receives and reproduces the media from the distribution server via a network. A media distribution method used for
A terminal information acquisition process in which the distribution server acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, terminal information acquired in the terminal information acquisition process, and a terminal in the terminal database Terminal performance discrimination processing for collating information to determine the processing capability and corresponding media format of the receiving terminal as terminal performance, memory capacity currently available from the receiving terminal, free state of the central processing unit, and disk capacity A terminal resource acquisition process that acquires at least a resource that includes the resource as an available resource, a connection environment determination process that determines an environment type to which the receiving terminal is connected as a connection environment, a band measurement process that measures a current band, and a connection Predicts future bandwidth fluctuations for a predetermined period of time based on the type of environment used and the current available bandwidth Even if the bandwidth fluctuates abruptly from the bandwidth fluctuation prediction processing for future bandwidth fluctuation, the terminal performance, the available resources, and the future bandwidth fluctuation, the receiving terminal does not interrupt the media and the quality of the media is high. A bit rate determination process for determining an optimum bit rate of the media that does not change rapidly in the future while maintaining quality, and an optimal encoding method for achieving the optimal bit rate is selected and An encoding process for encoding the medium and a distribution process for distributing the encoded medium to the receiving terminal;
The receiving terminal uses currently available resources from a buffering process for storing the media in a buffer for a predetermined time, a playback process for playing back the stored media, and the buffering process and the playback process. A terminal resource notification process is performed for acquiring as a possible resource and notifying the distribution server.
A program according to another aspect of the present invention is a program executed by a computer in a distribution server device that distributes media including at least video and music to a receiving terminal via a network.
A terminal information acquisition process that acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, a terminal information acquired in the terminal information acquisition process, and a terminal information in the terminal database are collated. A terminal performance determination process for determining the processing capability and corresponding media format of the receiving terminal as terminal performance, and a resource including at least the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity. Terminal resource acquisition processing to be acquired as a possible resource, connection environment determination processing to determine the environment type to which the receiving terminal is connected as a connection environment, bandwidth measurement processing to measure the current bandwidth, and connected environment type Predicts future bandwidth fluctuations for a predetermined period from the current available bandwidth and Even if the bandwidth suddenly fluctuates due to the bandwidth fluctuation prediction processing, the terminal performance, the available resources, and the future bandwidth fluctuation, the media is not interrupted at the receiving terminal and the quality of the media is maintained high. A bit rate determination process for determining an optimum bit rate of the medium that does not fluctuate rapidly in the future, and an optimum encoding method for selecting the optimum bit rate is selected to encode the medium. An encoding process and a distribution process for distributing the encoded media to the receiving terminal.

  The present invention is configured and operated as described above, so that even in an environment where the band frequently fluctuates, the quality of the media can be stably distributed as long as the user does not feel uncomfortable or unnatural. The effect that it can be obtained.

FIG. 1 is a block diagram showing the configuration of a media distribution system according to a first embodiment of the present invention.
FIG. 2 is a sequence chart showing the operation of the media distribution system according to the first embodiment of the present invention.
FIG. 3 is a diagram showing a setting example of the first bit rate according to the first embodiment of the present invention.
FIG. 4 is a diagram showing an example of setting the second bit rate according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a third bit rate setting example according to the first embodiment of the present invention.
FIG. 6 is a diagram showing an example of setting the fourth bit rate according to the first embodiment of the present invention.
FIG. 7 is a block diagram showing the configuration of a media distribution system according to the second embodiment of the present invention.
FIG. 8 is a block diagram showing the configuration of a media distribution system according to the third embodiment of the present invention.
FIG. 9 is a block diagram showing the configuration of a media distribution system according to the fourth embodiment of the present invention.
FIG. 10 is a block diagram showing the configuration of a media distribution system according to the fifth embodiment of the present invention.
FIG. 11 is a block diagram showing the configuration of a media distribution system according to the sixth embodiment of the present invention.
FIG. 12 is a block diagram showing the configuration of a media distribution system according to the seventh embodiment of the present invention.
FIG. 13 is a block diagram showing the configuration of a media distribution system according to the eighth embodiment of the present invention.
FIG. 14 is a block diagram showing the configuration of a media distribution system according to the ninth embodiment of the present invention.
FIG. 15 is a block diagram showing the configuration of a media distribution system according to the tenth embodiment of the present invention.
FIG. 16 is a block diagram showing the configuration of a media distribution system according to the eleventh embodiment of the present invention.
FIG. 17 is a block diagram showing the configuration of a media distribution system according to the twelfth embodiment of the present invention.
FIG. 18 is a block diagram showing the configuration of a media distribution system according to the thirteenth embodiment of the present invention.
FIG. 19 is a block diagram showing the configuration of a media distribution system according to the fourteenth embodiment of the present invention.
FIG. 20 is a block diagram showing the configuration of a media distribution system according to the fifteenth embodiment of the present invention.
FIG. 21 is a block diagram showing the configuration of a media distribution system according to the sixteenth embodiment of the present invention.
FIG. 22 is a block diagram showing the configuration of a media distribution system according to the seventeenth embodiment of the present invention.
FIG. 23 is a block diagram showing the configuration of a media distribution system according to the eighteenth embodiment of the present invention.
FIG. 24 is a block diagram showing the configuration of a media distribution system according to the nineteenth embodiment of the present invention.
FIG. 25 is a block diagram showing the configuration of a media distribution system according to the twentieth embodiment of the present invention.
FIG. 26 is a block diagram showing the configuration of a media distribution system according to the twenty-first embodiment of the present invention.
FIG. 27 is a block diagram showing the configuration of a media distribution system according to the twenty-second embodiment of the present invention.
FIG. 28 is a block diagram showing the configuration of a media distribution system according to the twenty-third embodiment of the present invention.
FIG. 29 is a block diagram showing the configuration of a media distribution system according to the twenty-fourth embodiment of the present invention.
FIG. 30 is a block diagram showing the configuration of a media distribution system according to the twenty-fifth embodiment of the present invention.
FIG. 31 is a block diagram showing the configuration of a media distribution system according to the twenty-sixth embodiment of the present invention.

  Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a media distribution system according to a first embodiment of the present invention. In FIG. 1, the media distribution system according to the first embodiment of the present invention includes a distribution server 1 that distributes media such as video and music, and a receiving terminal 5 that receives and reproduces media via a network 100. ing.
The distribution server 1 is composed of, for example, a personal computer (hereinafter referred to as a personal computer) or a workstation. The receiving terminal 5 includes, for example, a personal computer, a portable information terminal, a mobile phone, a portable music terminal, and an information home appliance, but may be a set top box or a television or radio having a network function. The network 100 includes, for example, the Internet or a LAN (Local Area Network). In addition to a wired LAN, a wireless LAN including Bluetooth (registered trademark), infrared communication, visible light communication, and ultrasonic communication may be used. .
The distribution server 1 includes a terminal information acquisition unit 11, a terminal database 12, a terminal performance determination unit 13, a terminal resource acquisition unit 14, a connection environment determination unit 15, a bandwidth measurement unit 16, and a bandwidth fluctuation prediction unit 17. , Bit rate determining means 18, encoding means 19, and distribution means 20.
The terminal information acquisition unit 11 acquires terminal information indicating the model of the receiving terminal 5 on the receiver side. The terminal performance discriminating means 13 compares the acquired terminal information with the terminal database 12 stored in advance by the system administrator, and discriminates the processing capability of the receiving terminal 5 and the corresponding media format as the terminal performance. The terminal resource acquisition unit 14 acquires from the receiving terminal 5 resources such as a currently available memory capacity, a CPU (central processing unit) (not shown) free space, a disk capacity, and the like as available resources.
The connection environment determination unit 15 determines whether the reception terminal 5 is connected via a broadband environment, a wireless LAN, or a mobile phone network, or the environment type to which the reception terminal 5 is connected as the connection environment. The band measuring unit 16 measures the current band.
The band fluctuation prediction means 17 predicts a future band fluctuation for a certain period of time predetermined by the system administrator from the connected environment type and the current band, and sets it as a future band fluctuation. Based on the above-mentioned terminal performance and future bandwidth fluctuation, the bit rate determining means 18 does not interrupt the media at the receiving terminal 5 even if the bandwidth suddenly fluctuates, and the media quality remains high while maintaining the high quality. The optimum media bit rate that does not fluctuate is determined. The encoding means 19 selects an optimal encoding method in order to achieve an optimal bit rate, and encodes the media. The distribution unit 20 distributes the media to the receiving terminal 5.
The receiving terminal 5 includes a buffering means 51 for storing media in a buffer (not shown) for a time specified in advance by a server administrator or a browsing user, a playback means 52 for playing back the stored media, and buffering. A terminal resource notifying unit 53 for acquiring a resource such as a currently available memory capacity, a CPU (not shown) free space or a disk capacity from the unit 51 and the reproducing unit 52 as an available resource and notifying the distribution server 1; I have.
FIG. 2 is a sequence chart showing the operation of the media distribution system according to the first embodiment of the present invention. FIG. 3 is a diagram showing an example of setting the first bit rate according to the first embodiment of the present invention. FIG. 4 is a diagram showing a second bit rate setting example according to the first embodiment of the present invention, and FIG. 5 is a diagram showing a third bit rate setting example according to the first embodiment of the present invention. FIG. 6 is a diagram showing a fourth bit rate setting example according to the first embodiment of the present invention. The operation of the media distribution system according to the first embodiment of the present invention will be described with reference to FIGS. Note that the processing operations shown in FIG. 2 (the operation of each means of the distribution server 1 and the operation of each means of the receiving terminal 5) are also realized by each CPU executing a program.
The distribution server 1 distributes media such as video and music to the receiving terminal according to a request from the receiving terminal 5. The media may include still images, text files, document files, and various computer application data files.
The receiving terminal 5 receives the media distributed from the distribution server 1 and reproduces it according to a user instruction. In addition to playback, user instructions may include, for example, rewind, fast forward, frame advance, double speed, skip for each scene, pause, and stop. The user instruction input method may be, for example, keyboard input, touch panel input, input using voice recognition or character recognition.
In the distribution server 1, when a distribution request is sent from the receiving terminal 5 (processing a1 in FIG. 2), the terminal information acquisition unit 11 acquires terminal information indicating the model of the receiving terminal 5 on the receiver side. (Processing a2 in FIG. 2). For example, the terminal information acquisition unit 11 reads information of a Web browser such as a user agent transmitted from the Web browser and determines the model of the receiving terminal 5.
The terminal performance determination means 13 connects the terminal information acquired from the receiving terminal 5 by the terminal information acquisition means 11 with the specifications and performance of the terminals registered in the terminal database 12 and requests current distribution. The processing capability of the receiving terminal 5 and the corresponding media format are determined as terminal performance (processing a3 in FIG. 2).
Here, the terminal database 12 stores the processing capability and the corresponding media format for each model of the receiving terminal 5 in a list format. The processing capacity includes, for example, CPU performance, memory capacity, storage capacity, screen size, screen display response, number of colors and contrast, network speed, supported network protocol, etc. It may be included.
Supported media formats include, for example, video and audio codecs, video frame size and frame rate, compression rate, number of colors, number of gradations, audio sampling rate, number of bits per sample, number of channels, and the like.
For registration in the terminal database 12, for example, a system administrator may input manually, or a printed specification table may be input after character recognition, or a specification by an electronic file from a receiving terminal manufacturer. You may register automatically based on a table.
The terminal resource acquisition unit 14 acquires resources such as the currently available memory capacity, CPU free space, and disk capacity acquired from the receiving terminal 5 as available resources (process a4 in FIG. 2).
The connection environment determining unit 15 determines whether the receiving terminal 5 is connected via a broadband environment, a wireless LAN, or a mobile phone network, or the environment type to which the receiving terminal 5 is connected as the connection environment (process a5 in FIG. 2). For example, the connection environment determining unit 15 may determine the network route by determining the network route based on the IP (Internet Protocol) address of the receiving terminal 5, or may estimate the speed by transmitting data to the receiving terminal 5 on a trial basis. May be. In the case of a mobile phone, since the IP address of the gateway with the Internet installed in each carrier is determined, it is easy to determine whether it is via a mobile phone network or from which carrier's mobile phone. Can be determined.
The band measuring unit 16 measures the current band (process a6 in FIG. 2). As a method for measuring the bandwidth, for example, data of a known size may be transmitted to the receiving terminal 5 on a trial basis and estimated from the speed.
The bandwidth fluctuation prediction means 17 calculates the future bandwidth fluctuation for a certain period of time that is determined in advance by the system administrator from the type of connection environment determined by the connection environment determination means 15 and the current bandwidth measured by the bandwidth measurement means 16. Prediction is performed, and the prediction result is set as future band fluctuation (process a7 in FIG. 2).
As a method of predicting the band fluctuation, for example, there is a method of constructing a model by regression analysis and obtaining the band fluctuation as a function from the model. At this time, the environment such as time zone and season may be taken into consideration. For example, in the morning on weekdays, there are many network users in contact with work, and the available bandwidth may be narrow, and the bandwidth can be estimated based on a model that incorporates the tendency.
In addition, it is possible to calculate the average of the bandwidth for each time zone in units of days and estimate that the bandwidth after a certain period is a value between the current bandwidth and the average value obtained in advance. Furthermore, the future band variation may be obtained simply by extrapolating a polynomial function to the past band variation.
The bit rate determination means 18 receives the reception terminal 5 from the terminal performance determined by the terminal performance determination means 13 and the bandwidth fluctuation predicted by the bandwidth fluctuation prediction means 17 so that the media quality does not change suddenly at the reception terminal 5. The optimum bit rate of the high-quality media to be distributed to is determined (process a8 in FIG. 2).
If the bit rate is made to accurately follow the band, for example, when the band fluctuates abruptly in communication with a mobile object such as a mobile phone, the image quality and sound quality change frequently, making it very difficult to view. In addition, when the bandwidth cannot be secured, it is impossible to view immediately. Therefore, in this embodiment, a bit rate having a certain margin from the band is set so that the bit rate does not change frequently even if the band fluctuates.
For example, as shown in FIG. 3, there is a method in which a certain time interval is set and the bit rate is set to be constant in accordance with the minimum band during the time as a method for gradual change of the bit rate. As a result, the media is distributed at a bit rate smaller than the average bandwidth, so that it is more resistant to unexpected variations in bandwidth. As a result, the bit rate can be prevented from changing abruptly even if the bandwidth drops more rapidly than expected.
Further, as a method of gradually changing the bit rate, as shown in FIG. 4, there is a method of setting a certain time interval and making the bit rate constant according to the average band within the time. By adopting this method, high-quality media can be distributed at a higher bit rate.
Further, as a method of slowing the change in the bit rate, as shown in FIG. 5, in the band fluctuation graph with the horizontal axis representing time and the vertical axis representing band, the bit rate is obtained by connecting the minimum points with a straight line. There are a method of setting and a method of converting a band fluctuation smoothed into a bit rate in a band fluctuation graph.
In addition to these, when the bandwidth fluctuation is rapid and the reliability of the future bandwidth is low, in order to ensure the stability of the quality of the media, as shown in FIG. Another method is to reduce the media bit rate.
The encoding means 19 selects an optimal encoding method and encodes the media in order to achieve the optimal bit rate determined by the bit rate determination means 18 (process a9 in FIG. 2). As an encoding method, for example, there is a method of selecting one of many video and audio codecs and adjusting the parameters.
The distribution unit 20 distributes the media encoded by the encoding unit 19 to the receiving terminal 5 (process a10 in FIG. 2). As described above, the receiving terminal 5 receives the media distributed from the distribution server 1 and reproduces it according to the user's instruction (process a11 in FIG. 2).
In the receiving terminal 5, the buffering means 51 stores the media for the time specified in advance by the server administrator or the browsing user in the buffer. The buffer may be a memory or a disk.
The reproduction unit 52 reproduces the media stored in the buffer by the buffering unit 51 in accordance with a user instruction. As the reproducing means 52, for example, a reproduction application program already installed in the receiving terminal 5 is used. Further, as the reproduction means 52, a dedicated application program that differs for each type of media may be downloaded from the distribution server 1 and reproduced.
The terminal resource notification unit 53 acquires resources such as the currently available memory capacity, CPU free space, and disk capacity from the buffering unit 51 and the reproduction unit 52 as available resources, and notifies the distribution server 1 of them. As a method for obtaining the resource, for example, a monitoring function such as a system monitor provided as standard in many OSs (operating systems) is used. As a method for obtaining the resource, software for obtaining the resource may be newly installed in the receiving terminal 5.
Thus, in this embodiment, the future bandwidth fluctuation can be predicted by the bandwidth fluctuation prediction means 17, and the current performance of the receiving terminal 5 is estimated by the terminal performance determination means 13 and the terminal resource acquisition means 14. be able to.
Further, in this embodiment, the bit rate determining means 18 determines the optimum bit rate for the current performance of the receiving terminal 5 so that the media quality does not change suddenly at the receiving terminal 5 based on the band fluctuation. In the receiving terminal 5, even if there is an abrupt band fluctuation, there is no abrupt bit rate fluctuation, and high quality media can be viewed without a sense of incongruity or unnaturalness.

FIG. 7 is a block diagram showing the configuration of a media distribution system according to the second embodiment of the present invention. 7, the media distribution system according to the second embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1, except that the time interval holding means 21 is added to the distribution server 1a. The same elements are denoted by the same reference numerals.
The time interval holding unit 21 holds a plurality of time intervals predetermined by the system administrator, and the terminal information acquisition unit 11, the terminal performance determination unit 13, the terminal resource acquisition unit 14, and the connection environment determination are performed based on these time intervals. The data are supplied to the means 15, the band fluctuation prediction means 17, and the bit rate determination means 18, respectively.
The terminal information acquisition unit 11 acquires terminal information indicating the model of the receiving terminal 5 on the receiver side at the time interval from the time interval holding unit 21. The terminal performance discriminating unit 13 compares the terminal information acquired by the terminal information acquiring unit 11 with the time interval from the time interval holding unit 21 with the terminal database 12 stored in advance by the system administrator, and receives the receiving terminal 5. Is determined as the terminal performance.
The terminal resource acquisition unit 14 acquires resources such as the memory capacity currently available, CPU free space, and disk capacity from the reception terminal 5 as available resources at the time interval from the time interval holding unit 21. The connection environment determination unit 15 determines whether the receiving terminal 5 is connected by a broadband environment, a wireless LAN, or a mobile phone network at the time interval from the time interval holding unit 21 or the environment type to which the receiving terminal 5 is connected. It is determined as
The bandwidth fluctuation predicting means 17 is a time interval from the time interval holding means 21, and is determined in advance by the system administrator from the environment type determined by the connection environment determining means 15 and the current bandwidth measured by the bandwidth measuring means 16. Estimate future bandwidth fluctuations for a certain period of time, and assume future bandwidth fluctuations. The bit rate determination means 18 is a time interval from the time interval holding means 21, even if the band fluctuates rapidly from the terminal performance determined by the terminal performance determination means 13 and the band fluctuation predicted by the band fluctuation prediction means 17. The receiving terminal 5 determines an optimal bit rate so that the media is not interrupted and the quality of the media is maintained high and does not change rapidly in the future.
The operation of the media distribution system according to the second embodiment of the present invention will be described with reference to FIG.
This embodiment is different from the above-described first embodiment of the present invention in that it has time interval holding means 21 for holding a plurality of time intervals predetermined by the system administrator. The time interval held in the time interval holding means 21 may be one, may be different depending on the means to be referred to, and varies in time series according to a predetermined rule. Also good.
The terminal information acquisition unit 11 acquires terminal information according to the time interval held in the time interval holding unit 21. Accordingly, in this embodiment, for example, even if the user changes the model of the receiving terminal 5 while viewing the media, it can be detected. It is possible to immediately detect the switching from a mobile phone to a large-screen TV in a situation where the user browses with a mobile terminal when going out and views media on a large-screen TV when returning home. Further, in this embodiment, for example, in the case of a receiving terminal that degrades due to performance or function being cut off due to running out of battery, the degeneration status can be detected sequentially.
The terminal performance discrimination means 13 re-extracts the terminal performance using the terminal database 12 as the terminal information changes. The terminal resource acquisition unit 14 acquires resources such as the currently available memory capacity, CPU free space, and disk capacity acquired from the receiving terminal 5 as available resources.
The connection environment determining unit 15 determines whether the receiving terminal 5 is connected in a broadband environment, a wireless LAN, or a mobile phone network according to the time interval held in the time interval holding unit 21 or the environment in which the receiving terminal 5 is connected. The type is determined as the connection environment. Thus, in this embodiment, for example, when the receiving terminal 5 is a mobile phone having a wireless LAN function, it can be immediately detected that the connection environment has been switched from the mobile phone network to the wireless LAN.
For example, the band fluctuation prediction unit 17 grasps the current band from the band measurement unit 16 for each time interval held in the time interval holding unit 21 and changes the band fluctuation prediction based on the current band. Thereby, in the present embodiment, the difference between the predicted bandwidth fluctuation and the actual bandwidth can be reduced.
The bit rate determining unit 18 determines the bit rate based on the predicted band fluctuation at each time point according to the time interval held in the time interval holding unit 21. As a result, in this embodiment, the optimum bit rate for the actual band can be sequentially determined.
Therefore, in this embodiment, the bandwidth fluctuation prediction means 17 can predict future bandwidth fluctuations at a time interval predetermined by the system administrator, and the terminal performance determination means 13 and the terminal resource acquisition means 14 can receive the receiving terminal. The current performance of 5 can be estimated.
In this embodiment, the bit rate determining means 18 manages the system based on the band fluctuation so that the media quality at the receiving terminal 5 does not fluctuate abruptly and is optimal for the current performance of the receiving terminal 5. The receiving terminal 5 can watch high-quality media without any sense of incongruity or unnaturalness, even if there is a sudden band fluctuation, and there is no sudden bit rate fluctuation. can do.

FIG. 8 is a block diagram showing the configuration of a media distribution system according to the third embodiment of the present invention. In FIG. 8, the media distribution system according to the third embodiment of the present invention is such that the advancement means 22 and the bandwidth fluctuation monitoring means 23 are added to the distribution server 1b, and the buffer size changing means 54 is added to the receiving terminal 5a. The configuration is the same as that of the first embodiment of the present invention shown in FIG. 1, and the same elements are denoted by the same reference numerals. This embodiment can also be applied to the second embodiment of the present invention described above.
In the distribution server 1b of the media distribution system, the bandwidth fluctuation monitoring means 23 is the bandwidth obtained by the bandwidth fluctuation prediction means 17 in the future predetermined by the system administrator. Whether or not the threshold value is smaller than the threshold value is monitored, and if it is predicted that the threshold value will be smaller than the threshold value, a warning message is sent to the advance means 22.
When receiving the warning message from the bandwidth fluctuation monitoring means 23, the advance sending means 22 has a threshold within a range predetermined by the system administrator and not exceeding the current bandwidth obtained from the bandwidth measuring means 16. The distribution means 20 is instructed to distribute media data of a future period that is smaller to the receiving terminal 5 in advance, and the receiving terminal 5b is instructed to change the buffer size and store the previously distributed media.
The buffer size changing means 54 instructs the buffering means 51 to change the buffer size when the receiving terminal 5b receives an instruction from the advance sending means 22.
The bandwidth fluctuation monitoring means 23 may be, for example, a constant predetermined by the system administrator as the threshold value, may adopt the bit rate determined by the bit rate determination means 18, A value multiplied by a constant may be used as the threshold value.
The advance sending means 22 delivers the future media in advance when there is a margin in the band. The situation where the bandwidth is sufficient is a situation where the media is delivered to the receiving terminal 5 as scheduled and the bit rate of the media delivered from the delivery means 20 is smaller than the current bandwidth.
At this time, for example, media of a predetermined future period are delivered to the receiving terminal 5 as a post-transmission in parallel with the media that is immediately played back by the receiving terminal 5a. If there is a margin in the bandwidth, it is possible to always postpone, or the user of the receiving terminal 5a may specify the timing of postponement. If a message for requesting to stop the forwarding is received from the receiving terminal 5a side, the forwarding may be stopped.
As for the amount of data to be postponed, for example, it may be postponed so that the bandwidth is exhausted so that there is no margin at all, or the amount of data to be postponed is determined by leaving a margin in the bandwidth as determined by the system administrator in advance. Also good.
The buffer size changing means 54 instructs the buffering means 51 to change the buffer size within the range allowed by the memory capacity of the receiving terminal 5a. If the receiving terminal 5a has no margin even if the designation of the advance is from the distribution server 1b, a message requesting the distribution server 1b to stop the advance may be transmitted.
Thus, in this embodiment, when the bandwidth fluctuation monitoring means 23 predicts that the bandwidth will be smaller than the threshold value, a warning message can be sent to the advance sending means 22.
In this embodiment, when the warning message is received by the advance sending means 22, the delivery means 20 is instructed to deliver to the receiving terminal 5a in advance the media data for the future period in which the bandwidth is smaller than the threshold value. It is possible to instruct the terminal 5a to change the buffer size and store the media distributed in advance.
In addition, in this embodiment, the buffer size can be changed by the buffer size changing means 54 when an instruction is received from the advance sending means 22. In the present embodiment, by these means, even when the communication band is remarkably reduced and the media cannot be distributed, the receiving terminal 5a can continue to play the media.

FIG. 9 is a block diagram showing the configuration of a media distribution system according to the fourth embodiment of the present invention. In FIG. 9, the media distribution system according to the fourth embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1, except that the moving image coding determination means 24 is added to the distribution server 1c. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second and third embodiments of the present invention described above.
The moving image coding determination unit 24 changes the frame size, frame rate, compression rate, number of colors, and number of gradations of the moving image with the optimal bit rate determined by the bit rate determining unit 18 as a target. The encoding means 19 is instructed to change the bit rate which is the size.
The moving image encoding determination unit 24 instructs the encoding unit 19 to change the size of the moving image, for example, by enlarging or reducing the vertical and horizontal size of one frame of the moving image. In this case, in the present embodiment, the aspect ratio that is the size ratio of the vertical and horizontal directions may be changed. Further, in this embodiment, even if the vertical and horizontal sizes of the moving image change, the playback means 52 may enlarge during playback so that the vertical and horizontal sizes do not change in the display. Furthermore, in the present embodiment, bi-linear or bicubic interpolation may be used as the inter-pixel interpolation for the enlargement / reduction of the frame, or the area average method may be used. Furthermore, in this embodiment, pixel values may be modeled and interpolated in a function form predetermined by the system administrator.
In addition, the moving image encoding determination unit 24 instructs the encoding unit 19 to change the size of the moving image, for example, by increasing or decreasing the frame rate. When reducing the frame rate, it may be simply thinned out. You may reduce by interpolating the frame between frames. When increasing the frame rate, the existing frame may be copied and increased as it is, or the frame between frames may be interpolated and increased.
As a method of interpolating frames between frames, pixel values may be interpolated by bilinear or bicubic, and pixel values may be modeled and interpolated by a function system predetermined by a system administrator. In this embodiment, an object such as a person in a frame may be cut out, and a change such as movement may be predicted for each object and may be interpolated.
In addition, the moving image encoding determination unit 24 instructs the encoding unit 19 to change the size of the moving image, for example, by changing the compression rate. The relationship between compression ratio and media size is generally not a linear relationship, but the relationship may be obtained by a system administrator preliminarily experimenting with test media. . Alternatively, in this embodiment, the system administrator may specify after searching for an optimal compression rate by repeating trial and error according to a predetermined procedure.
In addition, the moving image encoding determination unit 24 instructs the encoding unit 19 to change the size of the moving image, for example, by changing the number of colors. As a method for changing the number of colors, for example, a dither method may be used, or an image processing method such as a median cut method may be used.
In addition, the moving image encoding determination unit 24 instructs the encoding unit 19 to change the size of the moving image, for example, by changing the number of gradations. As a method of changing the number of gradations, for example, a dither method may be used, and a system administrator defines a function in advance for the original gradation and the gradation after the change, and conversion is performed according to the function. Good.
The moving image coding determination means 24 may further change the size of the moving image by selecting a plurality of frame rates, compression rates, the number of colors, and the number of gradations and changing them.
Thus, in the present embodiment, the moving image encoding determining means 24 can adjust the size of the media by changing the moving image frame size, the frame rate, the compression rate, the number of colors, and the number of gradations.

FIG. 10 is a block diagram showing the configuration of a media distribution system according to the fifth embodiment of the present invention. 10, the media distribution system according to the fifth embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1 except that the image processing means 25 is added to the distribution server 1d. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to fourth embodiments of the present invention described above.
The image processing means 25 smoothes the entire moving image frame with a uniform intensity with the optimum bit rate determined by the bit rate determining means 18 as a target, or changes the smoothing intensity at a portion of the frame. The encoding means 19 is instructed to change the bit rate, which is the media size, while suppressing the remarkable deterioration in image quality such as block noise by changing the smoothing intensity according to the intensity of motion.
For example, the image processing means 25 subdivides the image into rectangular blocks, smoothes the rectangular blocks included in a range predetermined by the system administrator, reduces the high-frequency region, increases the compression rate, and reduces the size of the moving image. To do. Alternatively, the image processing unit 25 reduces the size of the moving image by reducing the number of colors and the number of gradations.
For example, since the peripheral area of the image is not noticeable even when the image quality is lowered, the smoothing intensity may be increased only in the peripheral area, or the number of colors and the number of gradations may be reduced only in the peripheral area. Alternatively, by extracting an object such as a person and reducing the video size by increasing the compression rate or reducing the number of colors and gradations for the part other than the object, and a frame with intense motion The strength of smoothing may be increased or decreased with respect to the region or the time region.
Thus, in this embodiment, the entire frame of the moving image is smoothed with a uniform intensity by the image processing means 25, or the smoothing intensity is changed at a part of the frame, or is smoothed according to the intensity of the motion. By changing the intensity of the media size, it is possible to adjust the media size while suppressing a remarkable deterioration in image quality such as block noise.

FIG. 11 is a block diagram showing the configuration of a media distribution system according to the sixth embodiment of the present invention. In FIG. 11, the media distribution system according to the sixth embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1 except that a speech encoding determination means 26 is added to the distribution server 1e. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to fifth embodiments of the present invention described above.
The audio coding discrimination means 26 changes the audio sampling rate, the number of bits per sample, the frequency band, the number of channels such as stereo, etc., with the optimum bit rate determined by the bit rate determination means 18 as a target. The encoding means 19 is instructed to change the bit rate, which is the size of.
For example, the audio encoding determination unit 26 changes the size of the audio by increasing or decreasing the audio sampling rate. As a sampling rate conversion method, for example, samples may be interpolated by bilinear, bicubic, or polynomial functions, and a speech waveform may be modeled and interpolated according to the model.
In addition to this, the speech encoding determination means 26 changes the size of speech by increasing or decreasing the number of bits per sample, for example. As a method of increasing the number of bits, for example, the audio bit for each sample may be simply multiplied by a constant, or after the constant multiplication, the audio waveform may be modeled and the bit adjusted according to the model. Good. As a method for reducing the number of bits, for example, it may be simply divided by a constant.
In addition, the speech encoding determination means 26 changes the size of speech by changing the frequency band, for example. In this case, for example, the audio data may be reduced by cutting the high frequency without leaving a large difference in sound quality. As a method of changing the frequency band, for example, a FIR (Finite-Duration Impulse Response) filter or an IIR (Infinite-Duration Impulse Response) filter may be used, and by partially selecting the frequency band in Fourier space. The frequency band may be changed.
In addition, the audio encoding determination unit 26 may increase / decrease the size of the audio data by increasing / decreasing the number of channels, for example, when stereo is monaural.
The audio coding determination means 26 may further change the size of the audio by selecting a plurality of sampling rates, the number of bits per sample, the frequency band, the number of channels such as stereo, and changing each.
Thus, in this embodiment, the audio encoding determination means 26 can adjust the size of the media by changing the audio sampling rate, the number of bits per sample, the frequency band, the number of channels such as stereo, and the like. .

FIG. 12 is a block diagram showing the configuration of a media distribution system according to the seventh embodiment of the present invention. 12, the media distribution system according to the seventh embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1, except that the encoding selection means 27 is added to the distribution server 1f. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to sixth embodiments of the present invention described above.
The encoding selection unit 27 instructs the encoding unit 19 to change the bit rate, which is the size of the medium, by changing the codec itself of the medium with the optimum bit rate determined by the bit rate determining unit 18 as a target. .
For example, when the bit rate of the video distributed by MPEG2 (Moving Picture Experts Group 2) is lowered, the encoding selection unit 27 is more efficient H.264. The bit rate is changed by changing the codec, such as switching to H.264. For example, when the bit rate is increased or decreased, there is a method in which a system administrator determines in advance which codec to switch to depending on whether the bit rate is increased or decreased with respect to the original codec.
Thereby, in the present embodiment, the encoding selection means 27 can change the codec itself of the media to adjust the size of the media.

FIG. 13 is a block diagram showing the configuration of a media distribution system according to the eighth embodiment of the present invention. In FIG. 13, the media distribution system according to the eighth embodiment of the present invention is the first embodiment of the present invention shown in FIG. 1 except that the matrix holding means 28 and the combination selection means 29 are added to the distribution server 1g. The same components are denoted by the same reference numerals. This embodiment can also be applied to the second to seventh embodiments of the present invention.
The matrix holding means 28 is the frame size of the moving image, the frame rate, the compression rate, the number of colors, the number of gradations, the smoothing strength, the distribution of the smoothing strength on the frame, the audio sampling rate and the number of bits per sample. A matrix describing the bit rate achieved for each combination of frequency band, number of channels, and media codec.
The combination selection unit 29 selects an optimum encoding method for media to be delivered to the receiving terminal 5 from the matrix held in the matrix holding unit 28 based on the terminal performance and the band variation, and the combination selection unit 29 returns to the encoding unit 19. Instruct.
The matrix holding means 28 may be composed of, for example, commercially available database software. In this case, the frame size of the moving image stored in the matrix, the frame rate, the compression rate, the number of colors, the number of gradations, the smoothing strength, the distribution of the smoothing strength on the frame, the audio sampling rate, The number of bits per sample, frequency band, number of channels, and media codec are used as encoding parameters.
When a specific bit rate is specified, there may be a plurality of encoding parameters. The combination selection means 29 is determined by the bit rate determination means 18 with reference to the matrix held by the matrix holding means 28 described above. The optimum combination of encoding parameters for the selected bit rate is selected. The optimum combination of encoding parameters may be determined in advance by the system administrator or may be determined by the user of the receiving terminal 5, for example.
Thus, in this embodiment, the matrix holding means 28 causes the frame size of the moving image, the frame rate, the compression rate, the number of colors, the number of gradations, the smoothing strength, the distribution of the smoothing strength on the frame, It is possible to hold a matrix that describes the sampling rate, the number of bits per sample, the frequency band, the number of channels, and the bit rate achieved for each combination of media codecs.
In this embodiment, the combination selection unit 29 can select an optimal encoding method for media to be distributed from the matrix to the receiving terminal 5 based on the terminal performance and the band fluctuation.

FIG. 14 is a block diagram showing the configuration of a media distribution system according to the ninth embodiment of the present invention. 14, the media distribution system according to the ninth embodiment of the present invention is the same as the eighth embodiment of the present invention shown in FIG. 13 except that a scene discriminating means 30 is provided instead of the combination selecting means 29. The same symbols are attached to the same elements.
The scene discriminating unit 30 targets the optimum bit rate determined by the bit rate determining unit 18, the intensity of motion of a person or an object in the scene that affects compression efficiency, the complexity of an image in a frame, or a sports program Based on the content type as described above, the optimum encoding method of the media to be distributed to the receiving terminal 5 is selected from the matrix held by the matrix holding means 28, and the encoding means 19 is instructed.
For the content type, for example, it is possible to determine whether or not the scene has a strong motion from the magnitude of the motion vector. There are many methods for calculating the complexity of an image. For example, a fractal dimension may be used as proposed in Japanese Patent Application Laid-Open No. 09-016754.
Also, when a broadcast program is distributed as a medium, for example, if the classification of the program type can be made on a program basis by the electronic program guide, it can be determined in advance whether the movement is large. If it can be determined whether or not the motion is intense, for example, in a scene where the motion is small in MPEG, the error of inter-frame compression is reduced. can do. For scenes with large motion, the error of inter-frame compression becomes large, so high image quality can be realized by reducing the frequency of frames that include only difference information between frames.
Thus, in this embodiment, the scene discriminating unit 30 uses the intensity of the movement of the person or object in the scene that affects the compression efficiency, the complexity of the image in the frame, or the content type such as a sports program, It is possible to select an optimal encoding method for media to be distributed to the receiving terminal 5 from the matrix held by the matrix holding means 28. In the present embodiment, this means can automatically select an optimal combination from a large number of combinations of encoding parameters.

FIG. 15 is a block diagram showing the configuration of a media distribution system according to the tenth embodiment of the present invention. In FIG. 15, the media distribution system according to the tenth embodiment of the present invention is provided with a combination recommendation unit 31 instead of the combination selection unit 29, and an encoding candidate selection unit 55 is added to the receiving terminal 5b. The configuration is the same as that of the eighth embodiment of the present invention shown in FIG. 13, and the same elements have the same reference numerals.
The combination recommendation unit 31 is held in the matrix holding unit 28 based on the content type such as a sports program and the movement of a person or an object in the scene, with the optimum bit rate determined by the bit rate determining unit 18 as a target. A plurality of methods are selected as encoding method candidates from among the optimal encoding methods of media to be distributed from the existing matrix to the receiving terminal 5b, and the server administrator prepares a predetermined number and distributes the list to the receiving terminal 5b. Then, the encoding means 19 is instructed according to the encoding method instructed from the receiving terminal 5b.
In the receiving terminal 5b, the encoding candidate selection means 55 displays the encoding method candidate and makes the user select it, and sends the encoding method selected by the user to the distribution server 1i.
For example, the combination recommendation unit 31 may classify combinations of encoding parameters based on characteristics such as image quality priority and motion priority and send the classification to the receiving terminal 5b. The encoding candidate selection means 55 displays, for example, encoding parameter combinations and classifications such as image quality priority and motion priority on the screen of the receiving terminal 5b, and the combination selected by the user with the keyboard or mouse is sent to the distribution server 1i. Send.
Thus, in the present embodiment, the combination recommendation unit 31 delivers to the receiving terminal 5b from the matrix held in the matrix holding unit 28 based on the content type such as a sports program and the movement of a person or object in the scene. A plurality of methods can be selected as encoding method candidates from among the optimal media encoding methods, and a server administrator can prepare a predetermined number and distribute the list to the receiving terminal 5b.
Further, in this embodiment, the combination recommendation unit 31 can instruct the encoding unit 19 about the encoding method according to the encoding method instructed from the receiving terminal 5b.
In addition, in this embodiment, the encoding candidate selection means 55 displays the encoding scheme candidates on the receiving terminal 5b, causes the user to select, and sends the encoding scheme selected by the user to the distribution server 1i. be able to. By these means, in this embodiment, the user can select a combination of encoding parameters.

FIG. 16 is a block diagram showing the configuration of a media distribution system according to the eleventh embodiment of the present invention. In FIG. 16, the media distribution system according to the eleventh embodiment of the present invention is the same as the first embodiment of the present invention shown in FIG. 1 except that an error correction coding determination means 32 is added to the distribution server 1j. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to tenth embodiments of the present invention described above.
The error correction coding determination means 32 instructs the coding means 19 to add an error correction signal to the medium when distributing the medium from the distribution server 1j to the receiving terminal 5, and changes the strength of the error correction signal. Thus, the media size is changed with the optimum bit rate determined by the bit rate determining means 18 as a target.
Many methods have been proposed as error correction codes, but the system administrator selects them in advance. For example, a Hamming code or a Reed-Solomon code may be applied as the error correction code.
In this embodiment, for example, by increasing the number of redundant bits in the error correction code, the data size increases, but the error tolerance can be increased. Further, in this embodiment, for example, when the error occurrence probability is low on the transmission line, the number of redundant bits can be reduced to reduce the data size. Furthermore, in this embodiment, since the data size generated by the error correction code method is different, the size may be adjusted by selecting and switching the method.
Thus, in this embodiment, when the error correction encoding determination unit 32 distributes from the distribution server 1j to the receiving terminal 5, the encoding unit 19 is instructed to add an error correction signal to the media, and error correction is performed. By changing the signal strength, the size of the media can be adjusted.

FIG. 17 is a block diagram showing the configuration of a media distribution system according to the twelfth embodiment of the present invention. 17, the media distribution system according to the twelfth embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1 except that the encryption determination means 33 is added to the distribution server 1k. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to eleventh embodiments of the present invention described above.
The encryption determination unit 33 instructs the encoding unit 19 to encrypt the media when distributing the media from the distribution server 1k to the receiving terminal 5, and changes the encryption strength and the encryption algorithm itself. Thus, the media size is changed with the optimum bit rate determined by the bit rate determining means 18 as a target.
Many methods have been proposed as encryption algorithms, but the system administrator selects them in advance. For example, as an encryption algorithm, DES (Data Encryption Standard) or RSA (Rivest Shamir Adleman) may be applied.
In this embodiment, for example, the data size is increased by increasing the number of bits of the key, but it is possible to improve the difficulty in decrypting the code. Furthermore, in this embodiment, for example, when the communication path is confirmed to be safe, the data size can be reduced by reducing the number of bits of the key. In this embodiment, since the data size generated by the encryption algorithm is different, the algorithm may be selected to adjust the size.
Thus, in this embodiment, when the encryption determination unit 33 distributes from the distribution server 1k to the receiving terminal 5, the encoding unit 19 is instructed to encrypt the medium, and the encryption strength and encryption are determined. The size of the media can be adjusted by changing the algorithm itself.

FIG. 18 is a block diagram showing the configuration of a media distribution system according to the thirteenth embodiment of the present invention. 18, the media distribution system according to the thirteenth embodiment of the present invention is the same as that shown in FIG. 1, except that the terminal performance evaluation unit 34 is added to the distribution server 11 and the test media playback unit 56 is added to the receiving terminal 5c. The configuration is the same as that of the first embodiment of the present invention shown, and the same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to twelfth embodiments of the present invention described above.
The terminal performance evaluation means 34 holds the test medium in the distribution server 11 to check the performance of the receiving terminal 5c, distributes the test medium to the receiving terminal 5c, and receives an error message from the receiving terminal 5c. Is stored in the terminal database 12 as media that cannot be reproduced for each terminal.
The test media playback means 56 plays back the test media acquired via the buffering means 51 in the receiving terminal 5c, and sends an error message to the distribution server 11 if the test media cannot be played back normally. In this case, as a test medium, for example, a music or video medium having a short reproduction time is used.
The terminal performance evaluation means 34 may distribute the test medium when the receiving terminal 5c accesses the distribution server 11 for the first time, and always distributes the test medium before distribution every time the type of the distribution medium changes. May be. In addition, the terminal performance evaluation unit 34 may specify that the user of the receiving terminal 5c distributes the test media.
The test media playback means 56 may not only return an error message to the distribution server 11 when the test media cannot be played back, but also return a message to that effect when the test media can be played back normally. . Thereby, even if a failure occurs in the receiving terminal 5c due to the media and an error message cannot be transmitted to the distribution server 11, the distribution server 11 can detect the error.
Therefore, in this embodiment, the terminal performance evaluation unit 34 holds the test medium for examining the performance of the receiving terminal 5c, distributes the test medium to the receiving terminal 5c, and receives the test medium from the receiving terminal 5c. The error message can be stored in the terminal database 12 as a medium that cannot be reproduced for each terminal.
Also, in this embodiment, the test media playback means 56 plays back the test media acquired via the buffering means 51 in the receiving terminal 5c, and if it cannot be played back normally, an error message is sent to the distribution server 1l. Can be sent to. By these means, in this embodiment, the optimum media can be distributed even to a new model receiving terminal 5c whose type of viewable media is unknown.

FIG. 19 is a block diagram showing the configuration of a media distribution system according to the fourteenth embodiment of the present invention. 19, the media distribution system according to the fourteenth embodiment of the present invention has the same configuration as that of the first embodiment of the present invention shown in FIG. 1, except that the media dividing means 35 is added to the distribution server 1m. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to thirteenth embodiments of the present invention described above.
The media dividing unit 35 divides the media by obtaining a dividing point for dividing the media according to a rule predetermined by the system administrator. The bandwidth fluctuation prediction means 17 calculates the future bandwidth fluctuation for a certain period of time determined by the system administrator based on the connection environment obtained by the connection environment discrimination means 15 and the current bandwidth obtained by the bandwidth measurement means 16. The prediction is performed for each division point divided by the media dividing unit 35.
As a rule predetermined by the system administrator applied by the media dividing means 35, for example, there is a method of dividing at regular intervals. In the case of a broadcast program, there are a method of dividing each program and a method of dividing at the timing of CM (commercial) broadcasting.
Furthermore, as the above-mentioned rule, there is a method in which specific image processing and sound processing are performed, and a division point is determined based on a feature amount obtained as a result. For example, there are cases in which the opening or ending video and music of a program are determined in a broadcast program, and there is a method of registering them in advance and identifying and separating the opening and ending based on the degree of coincidence of images and sounds.
Furthermore, as the above-mentioned rule, there is a method in which video and music are determined for CMs, which are registered in advance, and the CMs are identified and separated based on the degree of matching of images and sounds.
Thus, in the present embodiment, the media dividing means 35 can divide the media according to a specific rule. Further, in this embodiment, the band fluctuation prediction means 17 can make predictions for each division point that is a segment of media.

FIG. 20 is a block diagram showing the configuration of a media distribution system according to the fifteenth embodiment of the present invention. 20, the media distribution system according to the fifteenth embodiment of the present invention is the same as the fourteenth embodiment of the present invention shown in FIG. 19 except that an audio dividing means 36 is provided instead of the media dividing means 35. The same symbols are attached to the same elements.
The voice dividing unit 36 divides the voice at a timing such as a voice silence area, speaker switching, music switching, and the like, and notifies the band fluctuation prediction unit 17 of the voice. Here, with respect to the detection of the silent area, for example, there is a method of considering the case where the sound volume is lower than a threshold predetermined by the system administrator as the silent area. As for detection of the silent area, for example, even if BGM (Back Ground Music) is sounding, there is a method of determining whether there is a person's speech and considering it as a silent area.
Many methods have been proposed for whether or not there is a person's utterance. For example, a spectrum analysis is performed, and if there is a characteristic unique to the person's voice, there is a utterance, and if it is not, there is no utterance. There is. The switching of speakers can be realized by using many proposed speaker identification techniques. The speaker identification method can also be applied to the switching of music.
Thus, in this embodiment, the voice dividing means 36 can divide the voice at a timing such as a voice silence area, speaker switching, music switching, and the like. By this means, in this embodiment, even if the quality of the sound is changed, the user's uncomfortable feeling at the moment when the quality changes can be minimized.

FIG. 21 is a block diagram showing the configuration of a media distribution system according to the sixteenth embodiment of the present invention. In FIG. 21, the media distribution system according to the sixteenth embodiment of the present invention is the same as the fourteenth embodiment of the present invention shown in FIG. 19 except that a moving image dividing means 37 is provided instead of the media dividing means 35. The same symbols are attached to the same elements. This embodiment can also be applied to the fifteenth embodiment of the present invention.
The moving image dividing unit 37 divides a moving image at a timing such as moving image cut or scene switching, and notifies the band fluctuation prediction unit 17 of the divided moving image. Many methods have been proposed for detecting video cuts and scene switching. For example, when the difference between frames is calculated at any time, and the difference exceeds a threshold set by the system administrator in advance. There is a method to consider that there was a switch.
Thereby, in this embodiment, the moving image dividing means 37 can divide the moving image at the timing of moving image cut or scene switching. By this means, in this embodiment, even if the quality of the moving image is changed, it is possible to minimize the user's uncomfortable feeling at the moment when the quality changes.

FIG. 22 is a block diagram showing the configuration of a media distribution system according to the seventeenth embodiment of the present invention. 22, the media distribution system according to the seventeenth embodiment of the present invention is the same as the fourteenth embodiment of the present invention shown in FIG. 19 except that a moving image / audio dividing means 38 is provided instead of the media dividing means 35. It has the same structure, and the same code | symbol is attached | subjected to the same element. This embodiment can also be applied to the fifteenth and sixteenth embodiments of the present invention described above.
The moving image / audio dividing means 38 compares the timing of the silent region of the sound, switching of the speaker, switching of the music, and the like with the timing of cutting of the moving image, switching of the scene, etc., and adopts either timing as a dividing point of the media. Whether to use either timing or both timings, or to divide audio and video at different timings is determined according to the rules established by the server administrator in advance, and the media is divided at a timing that does not make the user feel uncomfortable. The bandwidth fluctuation prediction means 17 is notified.
As the media division point, for example, there is a method of designating both the audio division and the moving picture division as division points. Also, as media division points, there are a method of selecting only an audio segment and a method of selecting only a video segment. Furthermore, as a media division point, for example, after there is an audio segmentation, wait for the video segmentation, and then use the video segmentation as the segmentation point. There is a method of waiting for a break of the voice and using the voice break as a dividing point.
Furthermore, for example, even when there is no video segmentation and only audio segmentation is detected, when it is determined that the user will not notice even if the screen is blurred or dark and the quality varies slightly There is a method in which the division of the voice is used as a dividing point. Similarly, for example, even when there is no audio segmentation and only video segmentation is detected, if it is determined that the user is not noticed even if the audio contains a lot of noise components and the quality varies slightly, There is a method that uses a video break as a dividing point.
Thus, in this embodiment, the moving image audio dividing means 38 compares the timing of the silent region of the sound, the switching of the speaker, the switching of the music, and the timing of the cutting of the moving image, the switching of the scene, etc. Decide whether to use either timing as a point, or both timings, or whether to divide audio and video at different timings according to the rules established by the server administrator in advance, Media can be separated at a timing that does not make the user feel uncomfortable. By this means, in this embodiment, even if the quality of the media is changed, it is possible to minimize the user's uncomfortable feeling at the moment when the quality changes.

FIG. 23 is a block diagram showing the configuration of a media distribution system according to the eighteenth embodiment of the present invention. In FIG. 23, the media distribution system according to the eighteenth embodiment of the present invention adds a reproduction status storage unit 39 and a retransmission control unit 40 to the distribution server 1q, and adds a reproduction location notification unit 57 to the receiving terminal 5d. Has the same configuration as that of the first embodiment of the present invention shown in FIG. 1, and the same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to seventeenth embodiments of the present invention described above.
The reproduction status saving means 39 receives the reproduction location of the medium being reproduced from the receiving terminal 5d, saves the reproduction location and the ID for identifying the medium, and when the user designates stop at the receiving terminal 5d, If the media could not be normally distributed to the receiving terminal 5d, the last location that was normally distributed is stored as an interruption location.
The retransmission control means 40 can start distribution from the interrupted point of the media to the receiving terminal 5d at the stage when the user instructs playback again on the receiving terminal 5d side, or can play from any point specified by the user on the receiving terminal 5d. In this way, the distribution unit 20 is instructed to start distribution from the location designated by the user to the receiving terminal 5d.
The playback location notifying means 57 acquires the media playback location from the playback means 52 and notifies the delivery server 1q of the media playback location.
As a method of designating the last part of the media to be stored by the reproduction status storage unit 39, for example, there is a method of indicating the time from the start of the media or a method of indicating the accumulated data size from the start of the media. For moving images, there are a method indicated by a frame number from the start of the media, a method of dividing the media into scenes, and numbering each scene to indicate the number.
Thus, in this embodiment, the playback status storage means 39 receives the playback location of the media being played back from the receiving terminal 5d, stores the playback location, the title of the media, and the ID for identifying the content, and the user receives it. When the stop is designated at the terminal 5d, or when the media cannot be normally distributed to the receiving terminal 5d due to a communication failure, the last part that has been normally distributed can be stored as the interruption part.
In the present embodiment, the distribution server 1q can grasp how far the receiving terminal 5d has successfully played back the media by the playback location notifying means 57 in the receiving terminal 5d.
Further, in this embodiment, when the user instructs reproduction again on the receiving terminal 5d side by the retransmission control means 40, distribution starts from the media interruption point to the receiving terminal 5d, or the user designates at the receiving terminal 5d. Thus, distribution can be started from the location designated by the user to the receiving terminal 5d so as to reproduce from the arbitrary location.
By these means, in this embodiment, even if the delivery cannot be received due to a communication failure or the like, the communication can be resumed from the point of time when the communication failure is recovered and can be normally viewed. Can play.

FIG. 24 is a block diagram showing the configuration of a media distribution system according to the nineteenth embodiment of the present invention. 24, the media distribution system according to the nineteenth embodiment of the present invention is the eighteenth embodiment of the present invention shown in FIG. 23 except that terminal registration means 41 and terminal identification means 42 are added to the distribution server 1r. The same elements are denoted by the same reference numerals.
The terminal registration means 41 registers a plurality of receiving terminals that the system administrator permits in advance to receive. The terminal identification unit 42 suspends the reproduction at the receiving terminal 5d, and then registers the receiving terminal in the terminal registration unit 41 at the stage of instructing reproduction again at a receiving terminal different from the receiving terminal 5d that has been reproduced so far. If it has been registered, the distribution means 20 is instructed to resume distribution from the interrupted point of the media to the receiving terminal. To display a message of disapproval.
As a method for registering a receiving terminal, for example, in the case of a mobile phone, it can be registered by a terminal ID. As a method for registering the receiving terminal, there is a method for registering based on the accessed IP address. Furthermore, as a method for registering a receiving terminal, for example, in the case of a personal computer or PDA, there are a method using a MAC (Media Access Control) address of a network interface as a terminal ID, and a method using an ID of a built-in disk as a terminal ID.
When an unauthorized terminal is accessed, there are, for example, a method of displaying a message of disapproval on the screen of the receiving terminal and a method of playing back specific media. There is also a method that allows an unregistered receiving terminal to play back only for a certain period of time. Further, in the case of an unregistered receiving terminal, there are methods for distributing media whose image quality is degraded by reducing the image size or media whose sound quality is degraded by narrowing the band.
As described above, in the case of an unregistered receiving terminal, an unregistered user can be obtained by partially exposing the media so that only a part of the scene can be viewed or only a part of the frame can be viewed. Can be registered.
Accordingly, in this embodiment, the terminal registration unit 41 can register a plurality of receiving terminals that are permitted to receive in advance. Further, in this embodiment, after the terminal identifying means 42 interrupts the reproduction at the receiving terminal 5d, the receiving terminal instructs the reproduction at a receiving terminal different from the receiving terminal that has been reproduced so far. It is checked whether the receiving terminal is registered in the terminal registration means 41. If it is registered, distribution to the receiving terminal is resumed from the interruption point of the media or an arbitrary point designated by the user. A message such as disapproval can be displayed to the receiving terminal.
By these means, in the present embodiment, even when the user changes the display device from, for example, a mobile phone to a PC (personal computer) or the like, the same content can be continuously viewed. Furthermore, in the present embodiment, by generating in advance optimum media for each terminal from previously registered terminal information, it can be provided immediately when requested by the user.

FIG. 25 is a block diagram showing the configuration of a media distribution system according to the twentieth embodiment of the present invention. 25, the media distribution system according to the twentieth embodiment of the present invention is the same as that shown in FIG. 1 except that the failure handling rule storage means 43 is added to the delivery server 1s and the failure handling playback means 58 is added to the receiving terminal 5e. The configuration is the same as that of the first embodiment of the present invention, and the same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to nineteenth embodiments of the present invention described above.
The failure handling rule storage unit 43 prepares a rule determined in advance by the server administrator as a failure handling rule for what to display on the receiving terminal 5e when media cannot be delivered due to communication failure or the like. The failure handling rule is stored and transmitted to the receiving terminal 5e, and the delivery means 20 is instructed to stop delivery when a failure occurs.
The failure handling playback means 58 instructs the playback means 52 to play back the media received so far or the media dedicated to the failure at the time of the failure according to the failure handling rules from the distribution server 1s. The failure handling playback unit 58 plays, for example, media that has been received so far and remains in the buffering unit 51 in the event of a failure, or is stored in advance in the receiving terminal by the system administrator or the receiving terminal user. The reproduction means 52 is instructed to reproduce the medium dedicated to the failure.
As a method of acquiring the media dedicated to the failure, for example, a method of acquiring via the network interface of the receiving terminal 5e, or saving in the external memory by a personal computer or the like different from the receiving terminal 5e, and the external memory is stored in the receiving terminal 5e. There is a way to get by wearing it. In the case of reproducing media at the time of failure, for example, when there are a plurality of media, there are a method of reproducing in a saved order, a designated order, and a method of reproducing in a random order. In addition, when there are a plurality of media, there is a method of playing back another media during the playback of each media.
Thus, in this embodiment, the server administrator determines in advance what to display on the receiving terminal 5e when the failure cannot be distributed by the failure handling rule storage means 43 in case the media cannot be distributed due to a communication failure or the like. The failure handling rule can be used as a failure handling rule, and this failure handling rule can be transmitted to the receiving terminal 5e to instruct the delivery means 20 to stop delivery when a failure occurs.
Further, in this embodiment, the failure handling playback means 58 can play back media received so far at the time of failure or media dedicated to failure according to the failure handling rules.

FIG. 26 is a block diagram showing the configuration of a media distribution system according to the twenty-first embodiment of the present invention. In FIG. 26, in the media distribution system according to the twenty-first embodiment of the present invention, the backup media distribution means 44 is added to the distribution server 1t, and the failure handling reproducing means 58 and the backup media storage means 59 are added to the receiving terminal 5f. Except for this, the configuration is the same as that of the first embodiment of the present invention shown in FIG. 1, and the same elements are denoted by the same reference numerals. This embodiment can also be applied to the second to twentieth embodiments of the present invention described above.
In the distribution server 1t, the spare media distribution unit 44 prepares a medium to be displayed on the receiving terminal 5f as a spare medium in case the medium cannot be distributed due to a communication failure or the like. Delivered to the receiving terminal 5f.
In the receiving terminal 5f, the spare media storage means 59 receives the spare media from the distribution server 1t and stores it in a dedicated buffer (not shown). The failure handling playback unit 58 instructs the playback unit 52 to display the spare media in accordance with the failure handling rule when a failure occurs.
As the spare media, there are, for example, trailers for movies and TV programs, and methods using CMs. The spare media may be distributed, for example, in a time zone determined by the system administrator, or may be distributed in a time zone specified by the user of the receiving terminal 5f. The spare media may be distributed simultaneously with the media that the user of the receiving terminal 5f is viewing, for example, when there is a sufficient bandwidth. Further, for example, when the user starts viewing on the receiving terminal 5f, the spare media may be distributed immediately before playback of the media to be viewed.
Thus, in the present embodiment, in preparation for a case where the media cannot be distributed due to a communication failure or the like by the backup media distribution unit 44, a media to be displayed on the receiving terminal 5f when the media cannot be distributed is prepared as a backup media. Media can be distributed to the receiving terminal 5f.
Further, in this embodiment, the spare medium can be saved in a dedicated buffer by receiving the spare medium at the receiving terminal 5f by the spare medium saving means 59. In addition to this, in the present embodiment, the spare media can be displayed by the failure handling reproducing means 58 according to the failure handling rules at the time of failure.
By these means, in this embodiment, even when the media distribution from the distribution server 1t is interrupted due to a communication failure and all the media in the buffer of the receiving terminal 5f have been reproduced, for example, a trailer, a premier video or an advertisement is used as a spare medium. By displaying, it is possible to prompt the user to continue viewing.

FIG. 27 is a block diagram showing the configuration of a media distribution system according to the twenty-second embodiment of the present invention. 27, the media distribution system according to the twenty-second embodiment of the present invention is the same as that shown in FIG. 1, except that presence acquisition means 45 is added to distribution server 1u and presence notification means 60 is added to receiving terminal 5g. The same components as those in the first embodiment are denoted by the same reference numerals. This embodiment can also be applied to the second to twenty-first embodiments of the present invention.
In the distribution server 1u, the presence acquisition unit 45 acquires the position and movement of the receiving terminal 5g from the receiving terminal 5g as presence. The bandwidth fluctuation prediction means 17 also uses the presence acquired by the presence acquisition means 45 when predicting future bandwidth fluctuation for a certain period.
In the receiving terminal 5g, the presence notification means 60 notifies the distribution server 1u of the position of the receiving terminal 5g and the degree of movement.
As a method for acquiring the presence, for example, there is a method in which a GPS (global positioning system) receiver is mounted on the receiving terminal 5g and a position is acquired from a GPS signal received by the receiver. Further, as a method of acquiring presence, it can be obtained from the radio wave intensity for each base station as in the case of a mobile phone, for example.
In addition, as a method of acquiring presence, for example, when using a hot spot which is a wireless LAN connection providing service, the position of the receiving terminal 5g can be estimated from the position of the hot spot.
The degree of movement of the receiving terminal 5g can be acquired by using, for example, an acceleration sensor or a gyro.
Thus, in the present embodiment, the presence acquisition unit 45 and the presence notification unit 60 can improve the prediction accuracy of future band fluctuations based on the position of the receiving terminal 5g and how it moves.

FIG. 28 is a block diagram showing the configuration of a media distribution system according to the twenty-third embodiment of the present invention. In FIG. 28, the media distribution system according to the twenty-third embodiment of the present invention adds a reception environment acquisition unit 46 to the distribution server 1v and adds a sensor 61 and a reception environment notification unit 62 to the reception terminal 5h. The configuration is the same as that of the first embodiment of the present invention shown in FIG. 1, and the same elements are given the same reference numerals. This embodiment can also be applied to the second to twenty-second embodiments of the present invention described above.
In the distribution server 1v, the reception environment acquisition means 46 acquires the physical environment such as the weather condition and electromagnetic environment around the reception terminal 5h as the reception environment from the reception terminal 5h. The band fluctuation prediction means 17 also uses the reception environment acquired by the reception environment acquisition means 46 when predicting future band fluctuation for a certain period.
In the receiving terminal 5h, the sensor 61 measures the physical environment such as ambient weather conditions and electromagnetic environment. The reception environment notification means 62 notifies the distribution server 1v of the physical environment measured by the sensor 61 as the reception environment.
For example, radio waves are strongly attenuated when rainfall is heavy. Depending on the activity of the ionosphere, wireless communication may be difficult. There are many types of sensors for measuring such physical environments, such as a rain gauge, a rain radar, an anemometer, a barometer, a geomagnetic meter, and an ionosphere measuring radar. For measurement of the physical environment, observation data from an earth observation satellite such as a meteorological satellite may be acquired and used.
Thus, in this embodiment, the reception environment acquisition unit 46 and the reception environment notification unit 62 can improve the prediction accuracy of future band fluctuations from the weather conditions and electromagnetic environment around the reception terminal 5h.

FIG. 29 is a block diagram showing the configuration of a media distribution system according to the twenty-fourth embodiment of the present invention. In FIG. 29, the media distribution system according to the twenty-fourth embodiment of the present invention adds a task acquisition unit 47 and a terminal resource prediction unit 48 to the distribution server 1w, and adds a task notification unit 63 to the receiving terminal 5i. The configuration is the same as that of the first embodiment of the present invention shown in FIG. This embodiment can also be applied to the second to twenty-third embodiments of the present invention described above.
In the distribution server 1w, the task acquisition unit 47 acquires the currently executed program type and execution history from the receiving terminal 5i. The terminal resource prediction unit 48 uses the average execution time of the program type designated by the system administrator in advance, the currently executing program type, the execution history, and the available resources obtained from the terminal resource acquisition unit 14. The resource that can be used in the future for a certain period is predicted as the future resource. The bit rate determining means 18 uses future resources instead of available resources when determining the bit rate.
In the receiving terminal 5i, the task notification unit 63 notifies the distribution server 1w of the currently executed program type and the execution history.
As a method for obtaining the type of program currently being executed and the execution history, for example, a monitoring function such as a system monitor or a task monitor that is normally provided in many OSs (operating systems) is used. As another method, software for obtaining the type of program being executed and the execution history may be newly installed in the receiving terminal 5i.
Thus, in the present embodiment, the task acquisition unit 47, the task notification unit 63, and the terminal resource prediction unit 48, based on resources such as memory capacity that can be used in the receiving terminal 5i in the future, CPU free space, disk capacity, and the like. Media that is more optimal for the receiving terminal 5i can be distributed.

FIG. 30 is a block diagram showing the configuration of a media distribution system according to the twenty-fifth embodiment of the present invention. 30, the media distribution system according to the twenty-fifth embodiment of the present invention has the same configuration as that of the twenty-second embodiment of the present invention shown in FIG. 27 except that presence prediction means 49 is added to the distribution server 1x. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the above-described twenty-third and twenty-fourth embodiments of the present invention.
In the distribution server 1x, the presence prediction means 49 predicts the future position and movement status for a certain period from the current position and movement status of the receiving terminal 5g obtained from the presence acquisition means 45, and sets it as the future presence. The bandwidth fluctuation prediction means 17 uses the future presence instead of the presence when predicting the future bandwidth fluctuation for a certain period.
As a method for predicting the presence, for example, there is a method in which a model is constructed by performing regression analysis on the existing presence and a band variation is obtained from the model as a function. In this method, the environment such as the time zone and season and the geography around the receiving terminal may be taken into consideration.
In the above-described method for predicting presence, for example, if there is a presence on a railroad track, a future position can be estimated by referring to a schedule. In the above-described method for predicting presence, for example, if it is a weekday morning, the route and time are fixed to some extent for commuting, and the presence can be easily estimated. Furthermore, in the above-described method for predicting presence, a polynomial function may be simply extrapolated to past presence.
Thus, in the present embodiment, the presence prediction means 49 can predict the future position and the state of movement of the receiving terminal 5g, and can improve the prediction accuracy of future band fluctuations.

FIG. 31 is a block diagram showing the configuration of a media distribution system according to the twenty-sixth embodiment of the present invention. 31, the media distribution system according to the twenty-sixth embodiment of the present invention has the same configuration as that of the twenty-third embodiment of the present invention shown in FIG. 28 except that a reception environment predicting means 50 is added to the distribution server 1y. The same elements are denoted by the same reference numerals. This embodiment can also be applied to the above-described twenty-second, twenty-fourth and twenty-fifth embodiments of the present invention.
In the distribution server 1y, the reception environment prediction unit 50 predicts future weather conditions and electromagnetic environment for a certain period from the current weather conditions and electromagnetic environment around the reception terminal 5h obtained from the reception environment acquisition unit 46, and receives the future reception environment. And The bandwidth fluctuation prediction means 17 uses the future reception environment instead of the reception environment when predicting future bandwidth fluctuation for a certain period.
As a method for predicting the weather conditions and the electromagnetic environment, various forecasting methods proposed so far may be used, or a weather forecast or the like that has been publicly disclosed may be used.
Thus, in this embodiment, the future weather conditions and electromagnetic environment around the receiving terminal 5h can be predicted by the reception environment predicting means 50, and the prediction accuracy of the future band fluctuation can be improved.
Although the present invention has been described with reference to the embodiments and examples, the present invention is not limited to these embodiments and examples. Those skilled in the art can make various modifications to the above-described embodiments and examples within the technical scope of the present invention.
In other words, the media distribution system of the present invention realizes high efficiency by changing the quality according to the bandwidth variation of communication, and enables browsing of media with stable quality by predicting the bandwidth variation. Thus, in the media distribution system of the present invention, even in an environment where the band fluctuates frequently, it is possible to distribute the media with a stable quality as long as the user does not feel uncomfortable or unnatural.
Furthermore, in the media distribution system of the present invention, it is possible to distribute optimal media to various receiving terminals without any delay even if the receiving terminal performance or communication environment varies.
A first media distribution system according to the present invention is a system that includes a distribution server that distributes media such as video and music, and a receiving terminal that receives and plays back media via a network. Terminal performance determining means for determining the processing capacity and corresponding media format, terminal resource acquiring means for acquiring resources such as the currently available memory capacity, CPU (central processing unit) free space and disk capacity from the receiving terminal, and reception Bandwidth prediction means for predicting future bandwidth fluctuations for a certain period of time determined in advance by the system administrator from the type of environment to which the terminal is connected and the current bandwidth, and the future performance predicted by the performance and available resources of the receiving terminal Optimum for high-quality media delivered to the receiving terminal so that the media quality at the receiving terminal does not fluctuate rapidly due to bandwidth fluctuations A bit rate determining means for determining a Bit Rate, and a coding means for coding the media by selecting an optimal encoding method to achieve the optimal bit rate.
In the first media distribution system of the present invention, the receiving terminal has terminal resource notification means for notifying the distribution server of resources such as the currently available memory capacity, CPU free space and disk capacity.
As a result, in the first media distribution system of the present invention, it becomes possible to predict future bandwidth fluctuation by the bandwidth fluctuation prediction means, and the terminal performance determination means and the terminal resource acquisition means can improve the current performance of the terminal. It becomes possible to guess.
Further, in the first media distribution system of the present invention, the bit rate determining means uses the bit that is optimal for the current performance of the receiving terminal so that the quality of the media does not change suddenly at the receiving terminal based on the band fluctuation. It is possible to determine the rate, and it is possible to view high-quality media without a sense of incongruity or unnaturalness even if there is a sudden band fluctuation at the receiving terminal, without a sudden bit rate fluctuation. .
A second media distribution system according to the present invention is a system composed of a distribution server that distributes media such as video and music, and a receiving terminal that receives and plays back media via a network. The terminal performance determination means for determining the processing capacity and the corresponding media format, the terminal resource acquisition means for acquiring resources such as the currently available memory capacity, CPU free space, and disk capacity from the receiving terminal, and the system administrator in advance A time interval holding means for holding a plurality of predetermined time intervals, an environment type to which the receiving terminal is connected, and a current bandwidth to predict future bandwidth fluctuations for a certain period of time determined by the system administrator in advance. Based on the bandwidth fluctuation prediction means and the performance and available resources of the receiving terminal and the predicted future bandwidth fluctuation, Bit rate determining means for determining an optimum bit rate of high-quality media to be delivered to a receiving terminal so as not to fluctuate rapidly, and an optimum code for achieving the optimum bit rate Encoding means for selecting the encoding method and encoding the media.
In the second media distribution system of the present invention, the receiving terminal has terminal resource notification means for notifying the distribution server of resources such as the currently available memory capacity, CPU vacancy and disk capacity.
As a result, in the second media distribution system of the present invention, it becomes possible to predict future bandwidth fluctuations at a time interval predetermined by the system administrator by means of the bandwidth fluctuation forecasting means. Depending on the means, it is possible to estimate the current performance of the terminal.
In the second media distribution system of the present invention, the bit rate is determined by the bit rate determining means so that the media quality at the receiving terminal does not fluctuate rapidly and the current performance of the receiving terminal is optimized. The system administrator can make a decision at predetermined time intervals, and even if there is a sudden change in bandwidth at the receiving terminal, there is no sudden change in the bit rate, and there is no sense of incongruity or unnaturalness. Media can be viewed.
In the third media distribution system of the present invention, in addition to the configuration of any of the first and second media distribution systems of the present invention described above, in the future predetermined by the system administrator, the above band fluctuation prediction Monitors whether the bandwidth obtained by the means is smaller than the threshold value determined by the system administrator, and sends a warning message to the advance means if it is predicted to be smaller than the threshold value. When receiving the message and the warning message, the media administrator receives the media data in the future period in which the bandwidth is less than the threshold within the range predetermined by the system administrator and not exceeding the current bandwidth obtained from the bandwidth measuring means. Instruct the delivery means to deliver to the terminal in advance, change the buffer size to the receiving terminal and save the media that was delivered in advance And a postponement means for instructing urchin.
The third media distribution system of the present invention further includes buffer size changing means for instructing the buffering means to change the buffer size when the receiving terminal receives an instruction from the advance sending means.
Thereby, in the third media distribution system of the present invention, when the bandwidth fluctuation monitoring means predicts that the bandwidth is smaller than the threshold value, it is possible to send a warning message to the advance sending means.
In the third media delivery system of the present invention, when the warning message is received by the advance means, the delivery means is instructed to deliver the media data in the future period in which the bandwidth is smaller than the threshold value to the receiving terminal in advance. Then, it is possible to instruct the receiving terminal to change the buffer size and store the media distributed in advance.
In addition, in the third media distribution system of the present invention, the buffer size can be changed by the buffer size changing means when receiving an instruction from the advance sending means. In the third media distribution system of the present invention, the media can be continuously played back by the receiving terminal by these means even in a state where the communication band becomes extremely small and the media cannot be distributed.
The fourth media distribution system according to the present invention includes a frame size, a frame rate, a compression rate, the number of colors, a floor of a moving image, in addition to the configuration of any of the first to third media distribution systems according to the present invention. It has a moving image coding discrimination means for instructing the coding means to change the size of the media by changing the logarithm.
Thus, in the fourth media distribution system of the present invention, the size of the media is adjusted by changing the frame size, frame rate, compression rate, number of colors, and number of gradations of the moving image by the moving image coding determining means. It becomes possible to do.
The fifth media distribution system according to the present invention smoothes the entire frame of a moving image with uniform intensity in addition to any one of the configurations of the first to fourth media distribution systems according to the present invention. The bit rate that is the media size can be reduced while suppressing the noticeable deterioration of image quality like block noise by changing the smoothing strength in the part of the image or by changing the smoothing strength according to the intensity of motion. Image processing means for instructing the encoding means to change is provided.
Thus, in the fifth media distribution system of the present invention, the entire frame of the moving image is smoothed with a uniform strength by the image processing means, or the smoothing strength is changed at a portion of the frame, By changing the level of smoothing according to the intensity, it is possible to adjust the media size while suppressing a noticeable deterioration in image quality such as block noise.
The sixth media distribution system of the present invention has a sampling rate of audio, the number of bits per sample, a frequency band, stereo, etc. in addition to the configuration of any of the first to fifth media distribution systems of the present invention described above. And a voice encoding discriminating unit for instructing the encoding unit to change the size of the media by changing the number of channels.
Thus, in the sixth media distribution system of the present invention, the size of the media is adjusted by changing the audio sampling rate, the number of bits per sample, the frequency band, the number of channels such as stereo, etc. It becomes possible to adjust.
In the seventh media distribution system of the present invention, in addition to the configuration of any of the first to sixth media distribution systems of the present invention described above, the media codec itself is changed to change the media size. It has a coding selection means for instructing the coding means.
As a result, in the seventh media distribution system of the present invention, it is possible to adjust the media size by changing the codec itself of the media by the encoding selection means.
The eighth media distribution system of the present invention has a frame size, a frame rate, a compression rate, the number of colors, a floor of a moving image, in addition to the configuration of any of the first to seventh media distribution systems of the present invention described above. Describes the bit rate achieved for each combination of logarithm, smoothing strength, distribution of smoothing strength on the frame, audio sampling rate and number of bits per sample, frequency band, number of channels, and media codec Matrix holding means for holding the matrix, and combination selection means for selecting an optimal encoding method for media to be distributed from the matrix to the receiving terminal based on terminal performance and bandwidth fluctuation.
Thus, in the eighth media distribution system of the present invention, the matrix holding means causes the frame size, the frame rate, the compression rate, the number of colors, the number of gradations, the smoothing strength, and the smoothing strength on the frame. It is possible to hold a matrix that describes the distribution of data, the sampling rate of audio, the number of bits per sample, the frequency band, the number of channels, and the bit rate achieved for each combination of media codecs.
In the eighth media distribution system of the present invention, it is possible to select an optimum encoding method of media to be distributed from the matrix to the receiving terminal based on the terminal performance and the band fluctuation by the combination selection unit. .
In addition to the configuration of the eighth media distribution system of the present invention described above, the ninth media distribution system of the present invention is a person in a scene that affects compression efficiency, the intensity of movement, and the complexity of an image in a frame. A scene discriminating unit that selects an optimal encoding method of media to be distributed from the matrix to the receiving terminal based on the content type such as the degree or the sports program is provided.
Thus, in the ninth media distribution system of the present invention, the scene discriminating means uses the intensity of the movement of the person or object in the scene that affects the compression efficiency, the complexity of the image in the frame, and the content such as the sports program. Based on the type, it is possible to select an optimal encoding method for media distributed from the matrix to the receiving terminal. In the ninth media distribution system of the present invention, it is possible to automatically select an optimum combination from a large number of combinations of encoding parameters by this means.
In addition to the configuration of the eighth media distribution system of the present invention described above, the tenth media distribution system of the present invention receives from a matrix based on the content type such as a sports program and the movement of a person or object in a scene. A plurality of methods are selected as encoding method candidates from among the optimal encoding methods for media to be delivered to the terminal, and the server administrator prepares a predetermined number of media, distributes the list to the receiving terminal, and receives instructions from the receiving terminal. And a combination recommendation unit for instructing the encoding method to the encoding unit according to the encoding method.
In the tenth media distribution system of the present invention, the encoding method candidates are displayed on the receiving terminal, the user selects them, and the media encoded by the encoding method selected by the user is sent to the distribution server. A candidate selection means.
Thus, in the tenth media distribution system of the present invention, the optimum code of the medium to be distributed from the matrix to the receiving terminal based on the content type such as a sports program and the movement of a person or object in the scene by the combination recommendation unit. It is possible to select a plurality of methods as encoding method candidates from among the encoding methods, prepare a predetermined number for the server administrator, and distribute the list to the receiving terminal.
In the tenth media distribution system of the present invention, the combination recommendation unit can instruct the encoding unit according to the encoding method instructed from the receiving terminal.
In addition, in the tenth media distribution system of the present invention, the encoding candidate selection means displays the encoding scheme candidates at the receiving terminal and allows the user to select the encoding scheme selected by the user. Can be sent to. By these means, in the tenth media distribution system of the present invention, the user can select a combination of encoding parameters.
When the eleventh media distribution system of the present invention distributes from the distribution server to the receiving terminal in addition to any one of the first to tenth media distribution systems of the present invention described above, Error correction coding determining means for changing the size of the medium by instructing to add an error correction signal to the medium and changing the strength of the error correction signal is provided.
Thus, in the eleventh media distribution system of the present invention, when distributing from the distribution server to the receiving terminal by the error correction encoding determination unit, the encoding unit is instructed to add an error correction signal to the medium. By changing the strength of the error correction signal, the size of the medium can be adjusted.
In the twelfth media distribution system of the present invention, in addition to any one of the first to eleventh media distribution systems of the present invention described above, when distributing from the distribution server to the receiving terminal, It has an encryption discrimination means for instructing to encrypt the media and changing the size of the media by changing the encryption strength and the encryption algorithm itself.
Thus, in the twelfth media distribution system of the present invention, when the encryption determination unit distributes from the distribution server to the receiving terminal, the encoding unit is instructed to encrypt the medium, The media size can be adjusted by changing the encryption algorithm itself.
A thirteenth media distribution system according to the present invention, in addition to any one of the first to twelfth media distribution systems according to the present invention described above, holds a test medium for examining the performance of the receiving terminal, Terminal performance evaluation means is provided for distributing the test medium to the receiving terminal, receiving an error message from the receiving terminal, and storing the medium in the terminal database as a non-reproducible medium for each terminal.
In the thirteenth media distribution system of the present invention, a test is performed in which the test media acquired through the buffering means is reproduced at the receiving terminal, and an error message is sent to the distribution server when the test media cannot be reproduced normally. Media playback means.
Accordingly, in the thirteenth media distribution system of the present invention, the terminal performance evaluation unit holds the test medium for examining the performance of the receiving terminal, distributes the test medium to the receiving terminal, and receives the test medium. An error message from the terminal can be described and stored in the terminal database as a non-reproducible medium for each terminal.
In the thirteenth media distribution system of the present invention, the test media playback means plays back the test media acquired through the buffering means at the receiving terminal by the test media playback means. Can be sent to the distribution server. In the thirteenth media distribution system of the present invention, these means can distribute optimal media even to a new model receiving terminal whose type of media that can be viewed is unknown.
A fourteenth media distribution system according to the present invention includes, in addition to any one of the first to thirteenth media distribution systems according to the present invention described above, a division point for dividing a medium according to a rule predetermined by a system administrator. Media dividing means for dividing the media by the time axis and band fluctuation predicting means for predicting future band fluctuation for each division point for a predetermined period determined in advance by a system administrator.
Thus, in the fourteenth media distribution system of the present invention, the media can be divided by a specific rule by the media dividing means. Further, in the fourteenth media distribution system of the present invention, it is possible to predict for each division point that is a delimiter of media by the band fluctuation prediction means.
In addition to the configuration of the fourteenth media distribution system of the present invention described above, the fifteenth media distribution system of the present invention includes a voice dividing means for dividing the voice at a timing such as a silent area of the voice, speaker switching, or music switching. Have.
Thus, in the fifteenth media distribution system of the present invention, the voice can be divided by the voice dividing means at the timing of the voice silence area, speaker switching, music switching, and the like. In the fifteenth media distribution system of the present invention, this means can minimize the user's uncomfortable feeling at the moment when the quality changes even if the quality of the voice is changed.
The sixteenth media distribution system of the present invention has a moving image dividing means for dividing a moving image at the timing of moving image cut or scene change in addition to the configuration of the fourteenth or fifteenth media distribution system of the present invention. ing.
Thus, in the sixteenth media distribution system of the present invention, the moving image dividing means can divide the moving image at the timing of moving image cut or scene change. In the sixteenth media distribution system of the present invention, even if the quality of the moving image is changed, it is possible to minimize the user's uncomfortable feeling at the moment when the quality changes.
The seventeenth media distribution system of the present invention, in addition to any of the configurations of the fourteenth to sixteenth media distribution systems of the present invention described above, is the timing of voice silence area, speaker switching, music switching, etc. Compare the timing of video cuts, scene changes, etc., and adopt either timing as the media division point, or both timings, or split audio and video at different timings Is determined according to a rule determined in advance by the server administrator, and has a moving image / sound dividing means for dividing the media at a timing at which the user does not feel uncomfortable.
Thus, in the seventeenth media distribution system of the present invention, the moving picture / voice dividing means compares the timing of the silent area of the voice, the switching of the speaker, the switching of the music, etc. with the timing of the cutting of the moving picture, the switching of the scene, etc. The server administrator decides in advance whether to use either timing, or both timings, or to divide audio and video at different timings. It is possible to divide the media at a timing that does not make the user feel uncomfortable.
In the seventeenth media distribution system of the present invention, even if the quality of the media is changed by this means, it is possible to minimize the user's uncomfortable feeling at the moment when the quality changes.
According to an eighteenth media distribution system of the present invention, in addition to the configuration of any one of the first to seventeenth media distribution systems of the present invention described above, a playback location of media being played back is received from a receiving terminal, and the playback location And the ID for identifying the media title and contents, and if the user specified stop at the receiving terminal, or if the media could not be successfully delivered to the receiving terminal due to a communication failure, the last location that was successfully delivered Is stored as an interrupted location, and when the user instructs playback again on the receiving terminal side, distribution of the media from the interrupted location to the receiving terminal is started, or any user specified at the receiving terminal In order to be able to reproduce from the location, it has retransmission control means for instructing the delivery means to start delivery from the location designated by the user to the receiving terminal.
In the eighteenth media distribution system of the present invention, the receiving terminal has a reproduction location notification means for acquiring a media reproduction location from the reproduction means and notifying the distribution server.
Thus, in the eighteenth media distribution system of the present invention, the playback status storage means receives the playback location of the media being played back from the receiving terminal, and stores the playback location, the title of the media, and the ID for identifying the content. When the user designates stop at the receiving terminal, or when media cannot be normally distributed to the receiving terminal due to a communication failure, the last part that has been normally distributed can be stored as an interrupted part.
In the eighteenth media distribution system of the present invention, it is possible for the distribution server to grasp how far the media can be normally reproduced at the receiving terminal by the reproduction location notifying means at the receiving terminal.
Furthermore, in the eighteenth media distribution system of the present invention, when the user instructs reproduction again on the receiving terminal side by the retransmission control means, distribution starts from the interrupted point of the medium to the receiving terminal or the user receives It is possible to start distribution from the location designated by the user to the receiving terminal so as to reproduce from any location designated by the terminal.
In the eighteenth media distribution system of the present invention, even when distribution cannot be received due to a communication failure or the like by these means, it is possible to resume from the point of time when normal viewing was possible after recovery from the communication failure. Playback from any specified location is possible.
In addition to the configuration of the eighteenth media distribution system of the present invention, the nineteenth media distribution system of the present invention is a terminal registration means for registering a plurality of receiving terminals that the system administrator permits in advance. Whether or not the receiving terminal is a receiving terminal registered in the terminal registration means at the stage where playback is instructed again at a receiving terminal different from the receiving terminal that has been played so far after the playback is interrupted at the receiving terminal If it has been registered, the distribution means is instructed to resume distribution to the receiving terminal from where the media was interrupted. If not registered, a message such as disapproval is displayed for the requested receiving terminal. Terminal identification means.
Thus, in the nineteenth media distribution system of the present invention, a plurality of receiving terminals permitted to receive in advance can be registered by the terminal registration means. In the nineteenth media distribution system of the present invention, after the reproduction is interrupted by the receiving terminal by the terminal identification unit, the reproduction is instructed to be reproduced again by the receiving terminal different from the receiving terminal that has been reproduced so far. Check if the receiving terminal is a receiving terminal registered in the terminal registration means, and if registered, resume delivery to the receiving terminal from the media interruption point or any point specified by the user, and unregistered In this case, it is possible to display a message such as disapproval for the requested receiving terminal.
In the nineteenth media distribution system of the present invention, by these means, even when the user changes the display device from, for example, a mobile phone to a PC (personal computer) or the like, the same content can be continuously viewed. It becomes. Furthermore, according to the nineteenth media distribution system of the present invention, an optimum medium is generated in advance for each terminal from previously registered terminal information, so that it is immediately provided when requested by the user. Is possible.
The twentieth media distribution system of the present invention cannot be distributed in case the medium cannot be distributed due to a communication failure or the like in addition to any one of the first to nineteenth media distribution systems of the present invention described above. In this case, what is displayed on the receiving terminal, a rule determined by the server administrator is stored as a failure handling rule, the failure handling rule is transmitted to the receiving terminal, and the delivery means is configured to stop the delivery when a failure occurs. Fault handling rule storage means for instructing
Further, the twentieth media distribution system of the present invention provides a failure handling that instructs the receiving terminal to play the media received so far or the media dedicated to the failure at the time of failure according to the failure handling rules. Reproduction means are provided.
Thus, in the twentieth media distribution system of the present invention, what is displayed on the receiving terminal in the case where the media cannot be distributed due to a communication failure or the like by the failure handling rule storage means, and the server management The rule determined by the person as a failure handling rule is transmitted to the receiving terminal, and the delivery means can be instructed to stop delivery when a failure occurs.
Further, in the twentieth media distribution system of the present invention, the failure handling playback means can play back the media received so far at the time of failure or the dedicated media at the time of failure according to the failure handling rules.
The twenty-first media distribution system of the present invention cannot be distributed in case the medium cannot be distributed due to a communication failure or the like in addition to any one of the first to twentieth media distribution systems of the present invention. In this case, a media to be displayed on the receiving terminal is prepared as a spare media, and spare media distribution means for distributing the media to the receiving terminal is provided.
Further, the twenty-first media distribution system of the present invention provides a spare media storage means for receiving spare media at a receiving terminal and storing the spare media in a dedicated buffer, and failure handling playback for displaying the spare media according to a fault handling rule when a fault occurs. Means.
Thus, in the twenty-first media distribution system of the present invention, the media to be displayed on the receiving terminal is prepared as a spare medium when the media cannot be delivered by the spare media delivery means due to a communication failure or the like. It becomes possible to deliver to the receiving terminal.
In the twenty-first media distribution system of the present invention, the backup media can be received at the receiving terminal by the backup media storage means and stored in a dedicated buffer. In addition, in the twenty-first media distribution system of the present invention, it is possible to display the spare media according to the failure handling rules at the time of failure by the failure handling playback means.
In the twenty-first media distribution system of the present invention, even when the media distribution from the distribution server is interrupted due to a communication failure and all the media in the buffer of the receiving terminal has been reproduced by these means, for example, a trailer or a premier is used as a spare medium. By displaying video and advertisements, the user can be encouraged to continue viewing.
According to a twenty-second media distribution system of the present invention, in addition to the configuration of any of the first to twenty-first media distribution systems of the present invention described above, the position and movement of the receiving terminal are indicated in the distribution server. Presence obtaining means for obtaining presence as a presence, and band fluctuation prediction means for using presence also when predicting future band fluctuation for a certain period of time. In addition, the twenty-second media distribution system of the present invention has presence notification means for notifying the distribution server of the position and movement in the receiving terminal.
Thus, in the twenty-second media distribution system of the present invention, the presence acquisition means and presence notification means can improve the prediction accuracy of future band fluctuations based on the position and movement of the receiving terminal.
The twenty-third media distribution system of the present invention includes, in addition to any one of the first to twenty-third media distribution systems of the present invention described above, the distribution server, such as weather conditions around the receiving terminal and electromagnetic environment. A receiving environment acquiring unit that acquires a physical environment as a receiving environment from a receiving terminal, and a band variation predicting unit that also uses the receiving environment when predicting a future band variation for a certain period.
The twenty-third media distribution system of the present invention includes a sensor for measuring a physical environment such as ambient weather conditions and electromagnetic environment in a receiving terminal, and a reception environment notification for notifying the distribution server of the physical environment as a reception environment. Means.
Thus, in the twenty-third media distribution system of the present invention, the reception environment acquisition means and the reception environment notification means can improve the prediction accuracy of future band fluctuations from the weather conditions and electromagnetic environment around the reception terminal. Become.
The twenty-fourth media distribution system of the present invention includes, in addition to the configuration of any of the first to twenty-third media distribution systems of the present invention described above, the program type currently being executed from the receiving terminal and execution in the distribution server. Using task acquisition means for acquiring history, average execution time and program type being executed in advance specified by the system administrator, execution history, and available resources obtained from terminal resource acquisition means It has terminal resource prediction means that predicts resources that can be used in the future for a certain period of time and uses them as future resources, and bit rate determination means that uses future resources instead of available resources when determining the bit rate. ing. The twenty-fourth media distribution system of the present invention has task notification means for notifying the distribution server of the currently executed program type and execution history in the receiving terminal.
Thus, in the twenty-fourth media distribution system of the present invention, the task acquisition means, task notification means, and terminal resource prediction means are used to obtain resources such as memory capacity, CPU free space, and disk capacity that can be used in the receiving terminal in the future. In addition, it is possible to distribute media more optimal for the receiving terminal.
According to a twenty-fifth media distribution system of the present invention, in addition to any of the configurations of the twenty-second to twenty-third media distribution systems of the present invention described above, the distribution server includes a current location of the receiving terminal and a condition of movement. Presence prediction means for predicting future positions and movements for a certain period of time to make future presence, and band fluctuation prediction means for using future presence instead of presence when predicting future band fluctuations for a certain period of time is doing.
As a result, in the twenty-fifth media distribution system of the present invention, it is possible to predict the future position and the state of movement of the receiving terminal by the presence prediction means, and it is possible to improve the prediction accuracy of future band fluctuations. Become.
The twenty-sixth media distribution system of the present invention includes, in addition to any of the configurations of the twenty-third to twenty-fifth media distribution systems of the present invention described above, current weather conditions and electromagnetic environment around the receiving terminal in the distribution server. A reception environment prediction means that predicts future weather conditions and electromagnetic environment for a certain period from the future and makes it a future reception environment, and band fluctuation prediction that uses the future reception environment instead of the reception environment when predicting future band fluctuations for a certain period Means.
Accordingly, in the twenty-sixth media distribution system of the present invention, it becomes possible to predict the future weather conditions and electromagnetic environment around the receiving terminal by the reception environment predicting means, and to improve the prediction accuracy of the future band fluctuation. It becomes possible.
This application is based on Japanese Patent Application No. 2007-048271 filed on Feb. 28, 2007, the entire disclosure of which is incorporated herein.

Claims (29)

A media distribution system comprising a distribution server that distributes media including at least video and music, and a receiving terminal that receives and reproduces the media from the distribution server via a network,
The distribution server includes a terminal information acquisition unit that acquires terminal information indicating a model of the receiving terminal, a terminal database that stores the terminal information in advance, terminal information acquired by the terminal information acquisition unit, and a terminal of the terminal database Terminal performance discrimination means for collating information to determine the processing capability of the receiving terminal and the corresponding media format as terminal performance, the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity. A terminal resource acquisition unit that acquires at least a resource that includes the resource as an available resource, a connection environment determination unit that determines an environment type to which the receiving terminal is connected, as a connection environment, a band measurement unit that measures a current band, and a connection Predicts future bandwidth fluctuations for a predetermined period of time based on the type of environment used and the current available bandwidth The bandwidth fluctuation prediction means for making the future bandwidth fluctuation, the terminal performance, the available resources, and the future bandwidth fluctuation, even if the bandwidth suddenly fluctuates, the receiving terminal does not interrupt the media and the quality of the media is high. A bit rate determining means for determining an optimum bit rate of the media that does not change rapidly in the future while maintaining quality, and an optimum encoding method for achieving the optimum bit rate is selected and Encoding means for encoding media, and distribution means for distributing the encoded media to the receiving terminal,
The receiving terminal uses a buffering means for storing the media in a buffer for a predetermined time, a playback means for playing back the stored media, and resources currently available from the buffering means and the playback means. A media distribution system comprising terminal resource notification means for acquiring as a possible resource and notifying the distribution server. The distribution server includes time interval holding means for holding a plurality of predetermined time intervals,
The terminal information acquisition means acquires the terminal information at time intervals from the time interval holding means;
The terminal performance determining means determines the terminal performance at a time interval from the time interval holding means;
The terminal resource acquisition unit acquires the available resource at a time interval from the time interval holding unit;
The connection environment determining means determines the connection environment at a time interval from the time interval holding means;
The band fluctuation prediction means predicts the future band fluctuation at a time interval from the time interval holding means;
2. The media distribution system according to claim 1, wherein the bit rate determination means determines the optimum bit rate of the media at a time interval from the time interval holding means. The distribution server monitors whether the bandwidth obtained by the bandwidth fluctuation prediction means is smaller than a predetermined bandwidth threshold and sends a warning message when it is predicted to be smaller than the threshold. The fluctuation monitoring means, and media data for a future period in which the bandwidth is smaller than the threshold within a range not exceeding the current bandwidth obtained from the bandwidth measurement means in a predetermined range when the warning message is received. Forward means for instructing the delivery means to deliver to the receiving terminal in advance and instructing the receiving terminal to change the buffer size and store the previously delivered media;
3. The medium according to claim 1, wherein the receiving terminal includes a buffer size changing unit that instructs the buffering unit to change a buffer size when receiving an instruction from the advance sending unit. Distribution system. The distribution server changes the bit rate by changing the frame size, the frame rate, the compression rate, the number of colors, and the number of gradations of the moving image with the optimal bit rate determined by the bit rate determining means as a target. The media distribution system according to any one of claims 1 to 3, further comprising a moving image encoding determination unit that instructs the encoding unit. The distribution server smoothes the entire frame of the moving image with uniform intensity, changes the intensity of smoothing at a portion of the frame, and moves the motion intensely with the optimal bit rate determined by the bit rate determining means as a target. Image processing means for instructing the encoding means to change the bit rate while suppressing a noticeable deterioration in image quality in the media by performing any one of the smoothing intensity changes depending on the length. The media distribution system according to any one of claims 1 to 4. The distribution server changes the bit rate by changing the audio sampling rate, the number of bits per sample, the frequency band, and the number of stereo channels with the optimum bit rate determined by the bit rate determining means as a target. The media distribution system according to claim 1, further comprising: a voice encoding determination unit that instructs the encoding unit. The distribution server includes encoding selection means for instructing the encoding means to change the code rate of the media by changing the codec itself of the medium with the optimum bit rate determined by the bit rate determination means as a target. The media distribution system according to any one of claims 1 to 6, wherein The distribution server includes a frame size, a frame rate, a compression rate, a color number, a gradation number, a smoothing strength, a smoothing strength distribution on a frame, a sound sampling rate, a number of bits per sample, Matrix holding means for holding a matrix describing a frequency band, the number of channels, and a bit rate achieved for each combination of the media codec, an optimum bit rate determined by the bit rate determining means, the terminal performance, and the 2. A combination selection unit that selects an optimal encoding method of media to be distributed from the matrix holding unit to the receiving terminal based on a band variation and instructs the encoding unit. The media distribution system according to claim 7. The distribution server targets the optimum bit rate determined by the bit rate determination means, and the intensity of motion of a person and an object in a scene that affects compression efficiency, the complexity of an image in the frame, and at least a sports program A scene discriminating unit for selecting an optimal encoding method for media to be distributed from the matrix holding unit to the receiving terminal based on a content type indicating the content of a program including The media distribution system according to claim 8. The distribution server uses the matrix holding unit based on a content type indicating the content of a program including at least a sports program with the optimal bit rate determined by the bit rate determining unit as a target, and movements of persons and objects in a scene. A plurality of methods are selected as encoding method candidates from optimal encoding methods of media to be distributed to the receiving terminal, and a list of a predetermined number of encoding method candidates is distributed to the receiving terminal, and the reception A combination recommendation unit that instructs the encoding unit according to an encoding method instructed by a terminal;
9. The receiving terminal includes encoding candidate selection means for displaying the encoding method candidates and sending media encoded by an encoding method selected by a user to the distribution server. Media distribution system. The distribution server instructs the encoding means to add an error correction signal to the medium when distributing the medium to the receiving terminal, and changes the strength of the error correction signal to determine the bit rate. The media distribution system according to any one of claims 1 to 10, further comprising error correction coding determination means for changing the size of the medium with the optimum bit rate determined by the means as a target. The distribution server instructs the encoding means to encrypt the medium when distributing the medium to the receiving terminal, and changes either the encryption strength or the encryption algorithm itself 12. The method according to claim 1, further comprising: an encryption determination unit that changes the size of the medium with the optimum bit rate determined by the bit rate determination unit as a target. Media distribution system. The distribution server holds test media having a plurality of codecs, a plurality of frame sizes, and a plurality of frame rates in order to check the performance of the receiving terminal, and distributes the test media to the receiving terminal. A terminal performance evaluation means for receiving an error message from the receiving terminal and describing it as a media format that cannot be played back for each terminal and storing it in the terminal database;
The receiving terminal has test media playback means for playing back the test media acquired via the buffering means and sending an error message to the distribution server when the test media cannot be played back normally. The media distribution system according to any one of claims 1 to 12, further comprising: The distribution server includes media dividing means for obtaining a dividing point for dividing the media according to a predetermined rule and dividing the media on a time axis,
The bandwidth fluctuation prediction means determines the future bandwidth fluctuation for a predetermined period of time for each division point based on the connection environment obtained by the connection environment discrimination means and the current bandwidth obtained by the bandwidth measurement means. The media distribution system according to any one of claims 1 to 13, wherein the media distribution system predicts and notifies the bit rate determination means. 15. The distribution server includes voice dividing means for dividing a voice at a timing including at least a silent area of a voice, speaker switching, and music switching and notifying the band fluctuation prediction means. Media distribution system. 16. The distribution server according to claim 14, further comprising a moving image dividing unit that divides the moving image at a timing including at least a cut of a moving image and a scene change and notifies the band fluctuation prediction unit. Media distribution system. The distribution server collates a first timing including at least a silent region of voice, speaker switching, and music switching with a second timing including at least moving image cut and scene switching. By dividing at least one of the first timing and the second timing according to a predetermined rule and dividing the media so as to change the bit rate at a timing that does not give the user a sense of incongruity in quality The media distribution system according to any one of claims 14 to 16, further comprising a moving image / sound dividing unit that notifies the band variation prediction unit. The distribution server receives the playback location of the media being played from the receiving terminal, stores the playback location and the identification information for identifying the title of the media and the contents thereof, and successfully distributes to the receiving terminal Reproduction status saving means for saving the last location as an interruption location, and instructions to the distribution means to start delivery from the location designated by the user to the receiving terminal when reproduction is instructed again on the receiving terminal side Resending control means for
The said receiving terminal includes the reproduction | regeneration location notification means which acquires the reproduction | regeneration location of the said media from the said reproduction | regeneration means, and notifies with respect to the said delivery server, The any one of Claims 1-17 characterized by the above-mentioned. Media distribution system. The distribution server is different from terminal registration means for registering a plurality of receiving terminals that are permitted to receive in advance, and a first receiving terminal that has been played back after interrupting playback of the media at the receiving terminal. It is checked whether the second receiving terminal is a receiving terminal registered in the terminal registering means when the second receiving terminal instructs reproduction again, and if the second receiving terminal has already been registered in the terminal registering means, Instructs the delivery means to resume delivery from the interrupted location to the second receiving terminal in the previous period, and at least for the receiving terminal that has requested reproduction of the media when not registered in the terminal registration means 19. The media distribution system according to claim 18, further comprising terminal identification means for transmitting an unauthorized message. The distribution server stores, as a failure handling rule, a predetermined rule indicating whether or not to display the predetermined media on the receiving terminal when the media cannot be delivered, and transmits the failure handling rule to the receiving terminal A failure handling rule storage means for instructing the delivery means to stop delivery of the media when a failure occurs,
20. The reception terminal includes a failure handling playback unit that instructs the playback unit to play the predetermined media according to the failure handling rule when the failure occurs. A media distribution system according to any one of the above. The distribution server uses the media to be displayed on the receiving terminal when the medium cannot be distributed as a backup medium, and distributes the media to the receiving terminal in advance before the band estimated by the band predicting unit becomes insufficient. Including spare media distribution means to
The receiving terminal includes a spare medium storage unit that receives the spare medium and stores it in a dedicated buffer, and a failure handling reproducing unit that instructs the reproducing unit to display the spare medium when a failure occurs. The media distribution system according to any one of claims 1 to 20, wherein the media distribution system is characterized in that: The distribution server includes presence acquisition means for acquiring the position of the receiving terminal and the degree of movement as presence from the receiving terminal;
The receiving terminal includes presence notification means for notifying the distribution server of the position and the state of movement,
The media distribution system according to any one of claims 1 to 21, wherein the bandwidth fluctuation prediction means uses the presence when predicting future bandwidth fluctuation for a certain period of time. The distribution server includes reception environment acquisition means for acquiring a physical environment including at least a weather condition and an electromagnetic environment around the reception terminal as a reception environment from the reception terminal,
The receiving terminal includes a sensor that measures the physical environment, and a reception environment notification unit that notifies the distribution server of the physical environment as the reception environment,
The media distribution system according to any one of claims 1 to 22, wherein the bandwidth variation prediction unit uses the reception environment when predicting future bandwidth variation for a certain period. The distribution server includes a task acquisition unit that acquires a currently executed program type and an execution history from the receiving terminal, an average execution time of a previously specified program type, the currently executed program type, and the execution history. Including a terminal resource prediction unit that predicts a resource that can be used in the future for a certain period of time using the available resource obtained by the terminal resource acquisition unit;
The receiving terminal includes task notification means for notifying the distribution server of the currently executing program type and the execution history,
The media distribution system according to any one of claims 1 to 23, wherein the bit rate determination means uses the future resource instead of the available resource when determining the bit rate. . The distribution server includes presence prediction means for predicting a future position and a state of movement for a certain period from a current position and a state of movement of the receiving terminal to be a future presence,
The media according to any one of claims 22 to 24, wherein the bandwidth fluctuation prediction means uses the future presence instead of the presence when predicting a future bandwidth fluctuation for a certain period of time. Distribution system. The distribution server includes reception environment prediction means for predicting a future physical environment for a certain period from the physical environment and setting it as a future reception environment,
The said bandwidth fluctuation | variation prediction means uses the said future reception environment instead of the said reception environment, when predicting the future band fluctuation | variation for a fixed period, The any one of Claims 23-25 characterized by the above-mentioned. Media distribution system. A distribution server device that distributes media including at least video and music to a receiving terminal via a network,
A terminal information acquisition unit that acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, a terminal information acquired by the terminal information acquisition unit, and a terminal information in the terminal database are collated. Terminal performance determining means for determining the processing capability and corresponding media format of the receiving terminal as terminal performance, and using resources including at least the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity A terminal resource acquisition unit that acquires as a possible resource, a connection environment determination unit that determines an environment type to which the receiving terminal is connected, as a connection environment, a band measurement unit that measures a current band, and a connected environment type Predicts future bandwidth fluctuations for a predetermined period from the current available bandwidth and The bandwidth fluctuation prediction means, the terminal performance, the available resources, and the future bandwidth fluctuation, even if the bandwidth suddenly fluctuates, the media is not interrupted at the receiving terminal and the quality of the media is maintained high. A bit rate determining means for determining an optimal bit rate of the medium that does not change rapidly in the future, and an optimal encoding method for achieving the optimal bit rate is selected to encode the medium. A distribution server device comprising encoding means and distribution means for distributing the encoded media to the receiving terminal. A media delivery method used in a system comprising a delivery server that delivers media including at least video and music, and a receiving terminal that receives and plays back the media from the delivery server via a network,
A terminal information acquisition process in which the distribution server acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, terminal information acquired in the terminal information acquisition process, and a terminal in the terminal database Terminal performance discrimination processing for collating information to determine the processing capability and corresponding media format of the receiving terminal as terminal performance, memory capacity currently available from the receiving terminal, free state of the central processing unit, and disk capacity A terminal resource acquisition process that acquires at least a resource that includes the resource as an available resource, a connection environment determination process that determines an environment type to which the receiving terminal is connected as a connection environment, a band measurement process that measures a current band, and a connection Predicts future bandwidth fluctuations for a predetermined period of time based on the type of environment used and the current available bandwidth Even if the bandwidth fluctuates abruptly from the bandwidth fluctuation prediction processing for future bandwidth fluctuation, the terminal performance, the available resources, and the future bandwidth fluctuation, the receiving terminal does not interrupt the media and the quality of the media is high. A bit rate determination process that determines the optimal bit rate of the media so that it does not fluctuate rapidly in the future while maintaining the quality,
An encoding process for selecting the optimal encoding method to achieve the optimal bit rate and encoding the media; and a distribution process for distributing the encoded media to the receiving terminal;
The receiving terminal uses currently available resources from a buffering process for storing the media in a buffer for a predetermined time, a playback process for playing back the stored media, and the buffering process and the playback process. A media distribution method, comprising: performing a terminal resource notification process of acquiring as a possible resource and notifying the distribution server. A program executed by a computer in a distribution server device that distributes media including at least video and music to a receiving terminal via a network,
A terminal information acquisition process that acquires terminal information indicating the model of the receiving terminal, a terminal database that stores the terminal information in advance, a terminal information acquired in the terminal information acquisition process, and a terminal information in the terminal database are collated. A terminal performance determination process for determining the processing capability and corresponding media format of the receiving terminal as terminal performance, and a resource including at least the memory capacity currently available from the receiving terminal, the free state of the central processing unit, and the disk capacity. Terminal resource acquisition processing to be acquired as a possible resource, connection environment determination processing to determine the environment type to which the receiving terminal is connected as a connection environment, bandwidth measurement processing to measure the current bandwidth, and connected environment type Predicts future bandwidth fluctuations for a predetermined period from the current available bandwidth and Even if the bandwidth fluctuates rapidly due to the bandwidth fluctuation prediction processing, the terminal performance, the available resources, and the future bandwidth fluctuation, the media is not interrupted at the receiving terminal, and the quality of the media is maintained high. A bit rate determination process for determining an optimal bit rate of the medium that does not change rapidly in the future, and an optimal encoding method for selecting the optimal bit rate is selected to encode the medium. A program comprising: an encoding process; and a distribution process for distributing the encoded media to the receiving terminal.

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