Method of transcoding documents in a network environment using a proxy server

• US 6,662,218 B2
• Filed: 09/20/2002
• Issued: 12/09/2003
• Est. Priority Date: 06/03/1996
• Status: Expired due to Term

• Current Assignee: Rovi Technologies Corporation (Adeia Inc.)
• Original Assignee: WebTV Networks Inc. (Microsoft Corporation)
• Inventors: Mighdoll, Lee S., Goldman, Phillip Y., Perlman, Stephen G., Leak, Bruce A.
• Primary Examiner(s): Barot, Bharat
• Application Number:
  US10/247,885
• Publication Number:
  US 20030014499A1
• Time in Patent Office: 445 Days
• Field of Search: 709/200-203, 709/217-219, 709/227-229, 709/231-232, 709/246-247
• US Class Current: 709/219
• CPC Class Codes: G06F 16/9577 Optimising the visualization of content, e.g. distillation of HTML documents
• CPC Class Codes: G06F 8/65 Updates security arrangements therefor G06F21/57
• CPC Class Codes: H04L 51/00 User-to-user messaging in packet-switching networks, transmitted according to store-and-forward or real-time protocols, e.g. e-mail
• CPC Class Codes: H04L 51/066 Format adaptation, e.g. format conversion or compression
• CPC Class Codes: H04L 51/224 providing notification on incoming messages, e.g. pushed notifications of received messages
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04M 2242/22 Automatic class or number identification arrangements
• CPC Class Codes: H04M 3/42059 Making use of the calling party identifier
• CPC Class Codes: H04N 19/40 using video transcoding, i.e. partial or full decoding of a coded input stream followed by re-encoding of the decoded output stream
• CPC Class Codes: H04N 19/46 Embedding additional information in the video signal during the compression process H04N19/517, H04N19/68, H04N19/70 take precedence
• CPC Class Codes: H04N 21/235 Processing of additional data, e.g. scrambling of additional data or processing content descriptors
• CPC Class Codes: H04N 21/2356 by altering the spatial resolution
• CPC Class Codes: H04N 21/2541 Rights Management protecting software against unauthorised usage in a vending or licensing environment G06F21/10; security in data switching network management H04L41/28; security management or policies for network security H04L63/20; access security in wireless networks H04W12/08
• CPC Class Codes: H04N 21/25808 Management of client data terminal profiles in network data switching protocols H04L67/303
• CPC Class Codes: H04N 21/25875 involving end-user authentication restricting access to computer systems by authenticating users using a predetermined code G06F21/33; arrangements for secret or secure communication including means for verifying the identity or authority of a user of the system H04L9/32; networks authentication protocols H04L63/08; authentication in wireless network security H04W12/06
• CPC Class Codes: H04N 21/25891 being end-user preferences retrieval of video data in a video database based on user preferences G06F16/739; arrangements for recognizing users' preferences H04H60/46; user profiles in network data switching protocols H04L67/306; processing of user preferences or user profiles in wireless networks H04W8/18
• CPC Class Codes: H04N 21/2662 Controlling the complexity of the video stream, e.g. by scaling the resolution or bitrate of the video stream based on the client capabilities
• CPC Class Codes: H04N 21/4331 Caching operations, e.g. of an advertisement for later insertion during playback
• CPC Class Codes: H04N 21/435 Processing of additional data, e.g. decrypting of additional data, reconstructing software from modules extracted from the transport stream
• CPC Class Codes: H04N 21/4622 : Retrieving content or additional data from different sources, e.g. from a broadcast channel and the Internet web site content organization and management for information retrieval from the Internet G06F16/958; transmission by internet of broadcast information H04H60/82; stock exchange data over packet-switching network H04L12/1804; push services including data channel over packet-switching network H04L12/1859
• CPC Class Codes: H04N 21/47 : End-user applications
• CPC Class Codes: H04N 21/478 : Supplemental services, e.g. displaying phone caller identification, shopping application
• CPC Class Codes: H04N 21/4782 : Web browsing , e.g. WebTV
• CPC Class Codes: H04N 21/4786 : e-mailing message switching systems, e.g. electronic mail systems H04L51/00
• CPC Class Codes: H04N 21/812 : involving advertisement data advertising per se G06Q30/02
• CPC Class Codes: H04N 21/8166 : involving executable data, e.g. software arrangements for executing specific programs G06F9/44; broadcasting computer programmes in broadcast systems H04H20/91; involving the movement of software or configuration parameters H04L67/34
• CPC Class Codes: H04N 5/602 : for digital sound signals
• CPC Class Codes: H04N 7/088 : the inserted signal being digital
• CPC Class Codes: Y10S 707/99939 : Privileged access
• CPC Class Codes: Y10S 707/99945 : Object-oriented database structure processing

Abstract

A method is described of providing a document to a client coupled to a server. The server functions as a proxy on behalf of the client for purposes of accessing a remote server. In the method, a document is retrieved from the remote server in response to a request from the client. The document includes data to be used by the client in generating a display. The proxying server alters (i.e., transcodes) the data in the document to form a transcoded document. The transcoded document is then transmitted to the client. The proxying server transcodes the data in the document in order to perform at least one of the following functions: (1) matching decompression requirements at the client; (2) converting the document into a format compatible for the client; (3) reducing latency experienced by the client; and (4) altering the document to fit into smaller memory space.

Claims

1. In a proxying server coupled to a client and to a remote server, the proxying server operating as a proxy on behalf of the client for accessing the remote server, a method of retrieving and transcoding a document requested by the client, the method comprising the steps of:

receiving, at the proxying server, a request for the document from the client, wherein the document resides at the remote server;

retrieving the document, the document including data for causing the client to generate a display of the document;

transcoding, at the proxying server, at least a portion of the document in order to perform at least one function selected from the following functions;

matching decompression requirements at the client;

converting the document into a format compatible for the client;

reducing latency experienced by the client; and

altering the document to fit into smaller memory space; and

transmitting the document to the client.

2. A method according to claim 1, wherein the request includes a URL (Uniform Resource Locator).

3. A method according to claim 1, wherein the step of transcoding is performed while the step of retrieving the document is performed.

4. A method according to claim 1, wherein the step of transcoding comprises the step of reading at least a portion of the document from a proxy cache located in the proxying server.

5. A method according to claim 1, wherein the step of transmitting the document to the client is performed prior to performing the step of transcoding, at the proxying server, the data in the document.

6. A method according to claim 1, wherein the step of transmitting the document to the client comprises the step of transmitting the transcoded document to the client, wherein the step of transmitting the document to the client is performed after the step of transcoding, at the proxying server, the data in the document.

7. A method according to claim 1, wherein the document includes a link to another document, the link including a retrieval address, and wherein the step of transcoding at the proxying server the data in the document comprises the step of updating the link.

8. A method according to claim 7, wherein the other document is an image, and wherein the step of updating the link comprises the step of adding information to the document indicating the size of the image.

9. A method according to claim 8, wherein the other document is inaccessible to the proxying server, and wherein the step of updating the link comprises the step of removing the link.

10. A method according to claim 7, wherein the other document has been relocated from the retrieval address to a redirect address, and wherein the step of updating the link comprises the step of updating the link to correspond to the redirect address.

11. A method according to claim 1, wherein the client includes a television display, wherein the document references an image, and wherein the step of transcoding, at the proxying server, the data in the document is conducted in order to perform at least the function of converting the document into a compatible format for the client, and comprises the step of revising the data such that the image is sized for display on the television display.

12. A method according to claim 1, wherein the document references an image having a first image format, and wherein the step of transcoding, at the proxying server, the document is conducted in order to perform at least the function of converting the document into a compatible format for the client, and includes the step of converting the first image format to a second image format.

13. A method according to claim 1, further comprising the steps of:

identifying an image referenced by the document;

determining whether the image has been previously retrieved by the proxying server; and

if the image has been previously retrieved by the proxying server, accessing information stored in the proxying server indicating the size of the image;

wherein the step of transcoding, at the proxying server, the data in the document is conducted in order to perform at least the function of reducing latency experienced by the client, and comprises the step of using the information indicating the size of the image to revise the data of the document to allow the document to be partially displayed by the client before the image is received by the client.

14. A method according to claim 13, wherein the step of transcoding, at the proxying server, the data in the document comprises the following step:

if the image has been previously retrieved by the proxying server, transcoding at the proxying server the data in the document without the image but providing a space for the image to be later inserted; and

wherein the step of transmitting the document to the client comprises the following steps;

transmitting the document to the client without the image but providing the space for the image to be later inserted; and

after transmitting the document to the client without the image, transmitting the image to the client.

15. In a proxying server coupled to a client and to a remote server, the proxying server operating as a proxy on behalf of the client for accessing the remote server, a method of retrieving and transcoding a document requested by the client, the method comprising the steps of:

providing a persistent database at the proxying server, the persistent database including information relating to the document;

receiving, at the proxying server, a request for the document from the client, wherein the document resides at the remote server;

retrieving the document, the document including data for causing the client to generate a display of the document;

transcoding, at the proxying server, at least a portion of the document using the information included in the persistent database in order to perform at least one function selected from the following functions;

matching decompression requirements at the client;

converting the document into a format compatible for the client;

reducing latency experienced by the client; and

altering the document to fit into smaller memory space; and

transmitting the document to the client.

16. A method according to claim 15, further comprising the step of storing in the persistent database validity information corresponding to the document.

17. A method according to claim 16, wherein the step of retrieving the document comprises the following steps:

retrieving the document from the persistent database if the validity information corresponding to the document indicates that the document is valid; and

retrieving the document from the remote server if the validity information corresponding to the document indicates that the document is not valid.

18. A method according to claim 16, wherein the step of storing in the persistent database validity information corresponding to the document comprises the step of observing a rate of change of the document.

19. A method according to claim 18, wherein the step of observing a frequency of change of the document comprises the step of periodically retrieving the document, wherein successive retrievals of the document are separated in time by at least a time interval.

20. A method according to claim 19, wherein the step of periodically retrieving the document comprises the following steps:

retrieving the document at a first time;

storing the document retrieved at the first time in a memory;

retrieving the document at a second time, the second time being at least the time interval after the first time;

determining whether the document retrieve at the second time has changed compared to the document retrieved at the first time;

if the document retrieved at the second time is different than the document retrieved at the first time, replacing the document retrieved at the first time with the document retrieved at the second time in the memory; and

if the document retrieved at the second time is the same as the document retrieved at the first time, extending the time interval.

21. A method according to claim 15, further comprising the step of storing in the persistent database performance information relating to performance of the remote server when accessing the document.

22. A method according to claim 21, wherein the performance information comprises a latency value.

23. A method according to claim 15, further comprising the step of storing in the persistent database information for optimizing memory usage by the client.

24. A method according to claim 15, wherein the step of retrieving the document comprises the following steps:

determining whether a redirect address corresponding to the document is stored in the persistent database;

if the redirect address corresponding to the document is stored in the persistent database, accessing the remote server using the redirect address, the remote server corresponding to the redirect address; and

if the redirect address corresponding to the document is not stored in the persistent database, the method further comprises the following steps;

accessing a previous remote server at which the document previously resided;

obtaining the redirect address from the previous remote server;

storing the redirect address in the persistent database; and

accessing the remote server using the redirect address.

25. A computer program product for implementing, in a proxying server coupled to a client and to a remote server, a method of retrieving and transcoding a document requested by the client, the computer program product comprising a computer-readable medium carrying computer-executable instructions for causing the proxying server to perform acts included in the method, said acts comprising:

receiving, at the proxying server, a request for the document from the client, wherein the document resides at the remote server;

retrieving the document, the document including data for causing the client to generate a display of the document;

transcoding, at the proxying server, at least a portion of the document in order to perform at least one function selected from the following functions;

matching decompression requirements at the client;

converting the document into a format compatible for the client;

reducing latency experienced by the client; and

altering the document to fit into smaller memory space; and

transmitting the document to the client.

26. A computer program product according to claim 25, wherein the computer-executable instructions comprise a plurality of program code means for transcoding at least a portion of the document, including:

program code means for transcoding at least a portion of the document so as to match decompression requirements at the client;

program code means for transcoding at least a portion of the document so as to convert the document into a format compatible with the client;

program code means for transcoding at least a portion of the document so as to reduce latency experienced by the client; and

program code means for transcoding at least a portion of the document so as to alter the document to fit into smaller memory space.

27. A computer program product according to claim 26, wherein the act of transcoding comprises selecting at least one of said plurality of program code means for transcoding for use in the act of transcoding.

28. A computer program product according to claim 25, wherein the act of transcoding is performed while the act of retrieving the document is performed.

29. A computer program product according to claim 25, wherein the act of transcoding comprises reading at least a portion of the document from a proxy cache located in the proxying server.

30. A computer program product according to claim 25, wherein the act of transmitting the document to the client is performed prior to performing the act of transcoding.

31. A computer program product according to claim 25, wherein the act of transmitting the document to the client comprises the act of transmitting the transcoded document to the client, wherein the act of transmitting the document to the client is performed after the act of transcoding.