Video server for video distribution system

• US 7,467,221 B2
• Filed: 04/19/2006
• Issued: 12/16/2008
• Est. Priority Date: 02/24/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Igawa, Masaru, Shibata, Koichi, Morita, Koichi, Sakamoto, Shuichi
• Primary Examiner(s): Dalencourt; Yves
• Application Number:
  US11/406,394
• Publication Number:
  US 20060195602A1
• Time in Patent Office: 972 Days
• Field of Search: 709/203, 709/219, 709/223, 709/226, 709/230, 709/231, 725/91, 725/93, 725/94, 725/114
• US Class Current: 709/231
• CPC Class Codes: H04N 21/21 Server components or server architectures
• CPC Class Codes: H04N 21/23 Processing of content or additional data; Elementary server operations; Server middleware

Abstract

A video server for distributing a digitized video content includes a unit for determining whether or not a video content requested from a terminal is stored in the video server, a unit for issuing a transmission request to another server for transmitting the video thereto in accordance with the HTTP protocol when the video content requested from the terminal is not stored in the video server, and a unit for receiving the video content transmitted from the other video server in accordance with the HTTP protocol, and transmitting the video content to the terminal in accordance with IP multicast or HTTP protocol.

Claims

1. A method of transferring image information in an asynchronous communication network, comprising the steps of:

detecting a random access point in image information to be transferred and storing the image information up to the next random access point in one of a plurality of buffers;

selecting image information which has not been transmitted and has a time stamp equal to or smaller than a reference time from among said plurality of buffers, transmitting the selected image information, and deleting the image information from the buffer after transmission; and

deleting image information which has not been transmitted and has a time stamp larger than the reference time from among said plurality of buffers,

wherein said image information transferring method further comprises the steps of;

receiving a request of the image information;

determining whether or not the requested image information is stored in a storage;

reading the image information from the storage for transmission when the requested image information is stored, and

requesting a video content provider to send the image information and receiving the image information for transmission when the requested image information is not stored in the storage.

2. The image information transferring method in accordance with claim 1, further comprising the step of:

storing the image information received from the video content provider in the storage.

3. The image information transferring method in accordance with claim 1, further comprising the steps of:

establishing a plurality of logical transmission paths to a destination of the image information; and

transmitting the image information read from the buffers to the destination using the plurality of logical transmission paths.

4. A video server for distributing a digitized video content via an asynchronous communication network, comprising:

a handler for detecting a random access point in the image information corresponding to the digitized video content and storing the image information up to the next random access point as one piece of information in one of a plurality of buffers which store pieces of image information;

a buffer controller for selecting one of the plurality of buffers to which the one piece of image information is stored and from which the one piece of image information is read;

a reference time generator for generating a reference time; and

a file reader for reading the one piece of image information from the buffers for transmission via the asynchronous communication network,

wherein the buffer controller selects, from among the plurality of buffers, the one piece of image information which has not been transmitted and has a time stamp equal to or smaller than a reference time generated by the reference time generator, and indicates the selected one piece of image information to the transmitter;

wherein said video server further comprises;

a video content storage for storing video contents, each video content consisting of pieces of image information, and

a video manager for determining whether or not a requested video content is stored in the video content storage,

wherein the video manager instructs the handler to read the video content from the video content storage for transmission when the requested video content is stored in the video content storage, and

wherein the video manager requests a video content provider to send the video content and instructs the handler to receive the video content for transmission when the requested video content is not stored in the video content storage.

5. The video server in accordance with claim 4, wherein the handler stores the video content received from the video content provider to the video content storage.

6. The video server in accordance with claim 4, wherein the transmitter establishes a plurality of logical transmission paths to a destination of the image information and transmits the pieces of image information from the buffers to the destination using the plurality of logical transmission paths.

7. The video server in accordance with claim 4, further comprising:

at least one additional transmitter for transmitting the same pieces of image information to at least one other destination in parallel with the transmitter.

8. An image transmission system for transmitting image information from a transmission side to a reception side via a network, comprising:

a plurality of logical transmission paths,

wherein said logical transmission paths are established in accordance with the HTTP protocol between a plurality of transmitters of the transmission side and a plurality of receivers of the reception side,

wherein the reception side includes a time stamp memory for storing a time stamp of reproduced image information,

wherein the transmission side transmits pieces of image information to the reception side from the transmitters through said plurality of logical transmission paths, each piece of image information including the time stamp, and

wherein the reception side receives the pieces of image information and compares the time stamp of the received piece of image information with the time stamp stored in the time stamp memory to reproduce only image information piece having a time stamp more recent than the stored time stamp.