Stream distribution system, stream server device, cache server device, stream record/playback device, related methods and computer programs

A stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, a plurality of terminal device that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, comprising:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding from height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from the cache server device, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream transmitting unit transmitting the stream from which control information has been removed to the cache server device before the preset distribution time indicated by the distribution request information, and to transmit the stream of control information to the cache device when the preset distribution time is reached.

A cache server device in a stream distribution system having a stream server device that stores streams which include contents and control information necessary for image playback of the contents, a plurality of terminal devices that playback received streams, and one or more of the cache server devices, each of which mediates between the stream server device and the terminal devices via a network, comprising:

• a time notifying unit transmitting to the stream server device a distribution request information indicating a preset distribution time at which the contents are permitted to be played;
• a receiving unit receiving a stream from which control information has been removed and a stream of control information, wherein the stream cannot be played without the control information, the control including information regarding frame height, time period different from prior VOP, and number of macroblocks;
• a storage unit storing the received stream from which control information has been removed;
• a combining unit combining the received stream of control information with the stream stored by the storage unit;
• and
• a stream transmitting unit transmitting a stream that results from the combining by the combining unit to one or more of the terminal devices.

A stream distribution system comprising a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices that are connected via a network, the stream server device including:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, form the cache server device, distribution request information including a preset distribution time at which the stream starts being distributed;
• and
• a stream transmitting unit transmitting the stream from which control information has been removed to one or more of the stream record/playback devices before the present distribution time, and to transmit the stream of control information to the one or more stream record/playback devices when the preset distribution time is reached, and
• the stream record/playback devices each including:
• a receiving unit receiving the stream from which control information has been removed and the stream of control information;
• a storage unit storing the received stream from which control information has been removed;
• a combining unit combining the received stream of control information with the stream stored by the storage unit;
• and
• a stream playback unit playing back a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.

A stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices that are connected via a network, comprising:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from the cache server device, distribution request information including a preset distribution time at which the stream starts being distributed;
• and
• a stream transmitting unit transmitting the stream from which control information has been removed to one or more of the stream record/playback devices before the present distribution time, and to transmit the stream of control information to the one or more stream record/playback devices when the preset distribution time is reached.

A stream record/playback device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of the stream record/playback devices, which are connected via a network, comprising:

• a receiving unit receiving a stream from which control information has been removed and a stream of control information, wherein the stream cannot be played without the control information, the control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a storage unit storing the received stream from which control information has been removed;
• a combining unit combining the received stream of control information with the stream stored by the storage unit;
• and
• a stream playback unit playing back a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.

A stream distribution method of a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, comprising:

• a separating step in the stream server device of separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition step in the stream server device of acquiring from the cache server device, distribution request information including a preset distribution time at which the stream starts being distributed;
• a first stream transmitting step in the stream server device of transmitting the stream from which control information has been removed to the cache server device before the the preset distribution time indicated by the distribution request information, and transmitting the stream of control information to the cache server device when the preset distribution time is reached;
• a time notifying step in the cache server device of transmitting to the stream server device the distribution request information;
• a receiving step in the cache server device of receiving the stream from which control information has been removed and the stream of control information;
• a storage step in the cache server device of storing the received stream from which control information has been removed;
• a combining step in the cache server device of combining the received stream of control information with the stream stored in the storage step;
• and
• a second stream transmitting step in the cache server device of transmitting a stream that results from the combining in the combining step to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A stream distribution method of a stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, comprising:

• a separating step of separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition step of acquiring from the cache server device, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream transmitting step of transmitting the stream from which control information has been removed to the cache server device before the preset distribution time indicated by the distribution request information, and transmitting the stream of control information to the cache server device when the preset distribution time is reached.

A stream transmit/receive method of a cache server device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and one or more of the cache server devices, each of which mediates between the stream server device and the terminal devices via a network, comprising:

• a time notifying step of transmitting to the stream server device a distribution request information including a preset distribution time at which the content starts being distributed;
• a receiving step of receiving a stream from which control information has been removed and a stream of control information, wherein the stream cannot be played without the stream of control information, the stream of control information including information regarding height, time period differential from prior VOP, and number of macroblocks;
• a storage step of storing the received stream from which control information has been removed;
• a combining step of combining the received stream of control information with the stream stored in the storage step;
• and
• a stream transmitting step of transmitting a stream that results from the combining in the combining step to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A stream distribution method of a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices that are connected via a network, comprising:

• a separating step in the stream server device of separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition step in the stream server device of acquiring from at least one of the plurality of stream record/playback devices, distribution request information including a preset distribution time at which the content starts being distributed;
• a stream transmitting step in the stream server device of transmitting the stream from which control information has been removed to one or more of the stream record/playback devices before preset distribution time, and transmitting the stream of control information to the one or more stream record/playback devices when the preset distribution time is reached;
• a time notifying step in the least one of the plurality of stream record/playback devices of transmitting to the stream server device the distribution request information;
• a receiving step in each stream record/playback device of receiving the stream from which control information has been removed and the stream of control information;
• a storage step in each stream record/playback device of storing the received stream from which control information has been removed;
• a combining step in each stream record/playback device of combining the received stream of control information with the stream stored in the storage step;
• and
• a stream playback step in each stream record/playback device of playing a stream that results from the combining in the combining step, the played stream being the same as the stream stored by the stream server device.

A stream distribution method of a stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices that are connected via a network, comprising:

• a separating step of separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition step of acquiring form the cache server device, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream transmitting step of transmitting the stream from which control information has been removed to one or more of the stream record/playback devices before the start time, and transmitting the stream of control information to the one or more stream record/playback devices when the preset distribution time is reached.

A stream record/playback method of a stream record/playback device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of the stream record/playback devices, which are connected via a network, comprising:

• a time notifying step of transmitting to the stream server device a distribution request information including a preset distribution time at which the content starts being distributed;
• a receiving step of receiving a stream from which control information has been removed and a stream of control information, wherein the stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a storage step of storing the received stream from which control information has been removed;
• a combining step of combining the received stream of control information with the stream stored in the storage step;
• and
• a stream playback step of playing a stream that results from the combining in the combining step, the played stream being the same as the stream stored by the stream server device.

A stream distribution system comprising a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, the stream server device including:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from the cache server device, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream record/transmit unit recording the stream from which control information has been removed onto a portable recording medium in advance, and to transmit the stream of control information to the cache server device when the preset distribution time is reached, and
• the cache server device including:
• a time notifying unit transmitting the distribution request information to the stream server device;
• a receiving unit receiving the stream of control information;
• an acquiring unit operable to acquire the stream, recorded onto the recording medium, from which control information has been removed;
• a combining unit combining the received stream of control information with the acquired stream;
• and
• a stream transmitting unit transmitting a stream that results from the combining by the combining unit to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, comprising:

• a separating unit separating a stream of control information from the stored stream;
• wherein the stored stream cannot be played back without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from the cache server device, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream record/transmit unit recording the stream from which control information has been removed onto a portable recording medium in advance, and to transmit the stream of control information to the cache server device when the preset distribution time is reached.

A cache server device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and the cache server device, which mediates between the stream server device and the terminal devices via a network, comprising:

• a time notifying unit transmitting distribution request information including a preset distribution time at which the content starts being distribute;
• a receiving unit receiving a stream of control information;
• an acquiring unit acquiring a stream, recorded onto a recording medium, from which control information has been removed, wherein the stream cannot be played back without the control information, the control information including information regarding frame height, time period differential form prior VOP, and number of macroblocks;
• a combining unit combining the received stream of control information with the acquired stream;
• and
• a stream transmitting unit transmitting a stream that results from the combining by the combining unit to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A stream distribution system comprising a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices, the stream server device including:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played back without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from at least one of the plurality of stream record/playback devices, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream record/transmit recording the stream from which control information has been removed onto a portable recording medium in advance, and to transmit the stream of control information to one or more of the stream record/playback devices via a network when the start time is reached, and
• the stream record/playback devices each including:
• a time notifying unit transmitting the distribution request information to the stream server device;
• a receiving unit receiving the stream of control information via the network;
• an acquiring unit acquiring the stream, recorded onto the recording medium, from which control information has been removed;
• a combining unit combining the received stream of control information with the acquired stream;
• and
• a stream playback unit playing back a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.

A stream server device in a stream distribution system having the stream server device, which stores a stream that includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices, comprising:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played back without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a time acquisition unit acquiring, from at least one of the plurality of stream record/playback devices, distribution request information including a preset distribution time at which the content starts being distributed;
• and
• a stream record/transmit unit recording the stream from which control information has been removed onto a portable recording medium in advance, and to transmit the stream of control information to one or more of the stream record/playback devices via a network when the preset distribution time is reached.

A stream record/playback device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of the stream record/playback devices, comprising:

• a receiving unit receiving a stream of control information via the network the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• an acquiring unit acquiring a stream, recorded onto a recording medium, from which control information has been removed, wherein the stream cannot be played back without the control information;
• a combining unit combining the received stream of control information with the acquired stream;
• and
• a stream playback unit playing back a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.

A stream distribution system comprising a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and a cache server device that mediates between the stream server device and the terminal devices via a network, the stream server device including:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played back without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• and
• a stream recording unit recording the stream from which control information has been removed onto a portable first recording medium, and to record the stream of control information onto a portable second recording medium, and
• the cache server device including:
• an acquiring unit acquiring the stream, recorded onto the first recording medium, from which control information has been removed, and the stream of control information recorded onto the second recording medium,
• a combining unit combining the stream of control information acquired from the second recording medium with the stream acquired from the first recording medium;
• and
• a stream transmitting unit transmitting a stream that results from the combining by the combining unit to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A cache server device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, a plurality of terminal devices that playback a received stream, and the cache server device, which mediates between the stream server device and the terminal devices via a network, comprising:

• an acquiring unit acquiring a stream, recorded onto a portable first recording medium, from which control information has been removed, and a stream of control information recorded onto a portable second recording medium, wherein the stream cannot be played back without the control information, the control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a combining unit combining the stream of control information acquired from the second recording medium with the stream acquired from the first recording medium;
• and
• a stream transmitting unit transmitting a stream that results from the combining by the combining unit to one or more of the terminal devices, the transmitted stream being the same as the stream stored by the stream server device.

A stream distribution system comprising a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of stream record/playback devices, the stream server device including:

• a separating unit separating a stream of control information from the stored stream, wherein the stored stream cannot be played back without the stream of control information, the stream of control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• and
• a stream recording unit operable to record the stream from which control information has been removed onto a portable first recording medium, and to record the stream of control information onto a portable second recording medium, and
• the stream record/playback devices each including:
• an acquiring unit acquiring the stream, recorded onto the first recording medium, from which control information has been removed, and the stream of control information recorded onto the second recording medium;
• a combining unit combining the stream of control information acquired from the second recording medium with the stream acquired from the first recording medium;
• and
• a stream playback unit operable to playback a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.

A stream record/playback device in a stream distribution system having a stream server device that stores a stream which includes a content and control information necessary for image playback of the content, and a plurality of the stream record/playback devices, comprising:

• an acquiring unit acquiring a stream, recorded onto a portable first recording medium, from which control information has been removed, and a stream of control information recorded onto a portable second recording information medium, wherein the stream cannot be played back without the control information, the control information including information regarding frame height, time period differential from prior VOP, and number of macroblocks;
• a combining unit combining the stream of control information acquired from the second recording medium with the stream acquired from the first recording medium;
• and
• a stream playback unit operable to playback a stream that results from the combining by the combining unit, the played stream being the same as the stream stored by the stream server device.