Explicit server control of transcoding representation conversion at a proxy or client location

• US 20040221063A1
• Filed: 02/13/2004
• Published: 11/04/2004
• Est. Priority Date: 02/08/2000
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Mogul, Jeffrey Clifford
• Granted Patent: US 7,287,094 B2
• Time in Patent Office: Days
• US Class Current: 709/246
• CPC Class Codes: H04L 67/565 Conversion or adaptation of application format or content adding application control or application functional data H04L67/561
• CPC Class Codes: H04L 67/5651 Reducing the amount or size of exchanged application data
• CPC Class Codes: H04L 67/75 Indicating network or usage conditions on the user display

Abstract

Information returned by a server to a client includes instructions, executable by either a proxy server or the client, for converting the returned information from a first representation to a second representation. The representation conversion may be made by a proxy server, for example, to make transmission of the returned information to the client more efficient, and/or to render the returned information in a format suitable for display by the client. By having the server embed representation conversion information in the query response, the representation conversion can take into account the type and other characteristics of information being returned, as well as the computational and display characteristics of the client.

Claims

1. A method for converting data from a first representation to a second representation in a network environment, comprising:

receiving a request from at least one client;

specifying a representation conversion program in a response to said request; and

sending said response to a destination;

wherein said specified representation conversion program is configured for execution by a computer at said destination to convert said response from a first representation thereof to a second representation thereof.

2. The method of claim 1, wherein said response includes data having an associated content type and said specifying a representation conversion program comprises selecting one of a set of representation conversion programs based on said content type.

3. A method for converting data from a first representation to a second representation in a network environment, comprising:

receiving a request from at least one client;

specifying at least one directive statement in a response to said request; and

sending said response to a destination;

wherein said response can be converted by a computer at said destination from a first representation thereof to a second representation thereof in accordance with said at least one directive statement.

4. The method of claim 3 wherein the directive statement is provided in a header of the response.

5. The method of claim 3 wherein the directive statement comprises information associated with an amount of information removable from an image.

6. The method of claim 5 wherein the directive statement comprises information associated with a size of the image.

7. The method of claim 3 wherein the directive statement comprises information associated with a time required to convert the response from the first representation to the second representation.

8. A method for converting data from a first representation to a second representation in a network environment, comprising:

receiving from a server a response to a request, said request having been sent by at least one client to said server;

determining at least one directive statement from said response; and

executing said at least one directive statement to convert said response from a first representation to a second representation.

9. The method of claim 8 wherein the at least one directive statement comprises information in a transcode-info header line.

10. The method of claim 8 wherein the at least one directive statement specifies reducable portions of an image.

11. The method of claim 8 wherein the at least one directive statement specifies unreducable portions of an image.

12. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism for converting data from a first representation to a second representation in a network environment, comprising:

logic code for receiving from a server a response to a request, said request having been sent by at least one client to said server;

logic code for retrieving a representation conversion program, the representation conversion program having been specified in said response; and

logic code for applying the representation conversion program to convert said response from a first representation thereof to a second representation thereof.

13. The computer program product of claim 12, wherein the representation conversion program is specified in a header portion of said response from said server.

14. The computer program product of claim 13, wherein the representation conversion program includes a first subprocedure for determining whether or not to apply the representation conversion program to said response, and the logic code for applying the representation conversion program includes logic code for executing the subprocedure to determine whether or not to apply the representation conversion program to said response.

15. The computer program product of claim 13, wherein the representation conversion program includes a subprocedure for determining one or more conversion control parameters that correspond to a maximum acceptable amount of data degradation to be caused by applying the representation conversion program to said response, and the logic code for applying the representation conversion program includes logic code for applying the representation conversion program to said response using the determined one or more conversion control parameters.

16. The computer program product of claim 13, wherein said logic code for retrieving includes logic code for retrieving said specified program from a local cache in said computer system.

17. The computer program product of claim 13, wherein said logic code for retrieving includes logic code for downloading said specified program from a location remote from said proxy server.

18. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism for converting data from a first representation to a second representation in a network environment, comprising:

logic code for receiving a request from at least one client;

logic code for specifying a representation conversion program in a response to said request; and

logic code for sending said response to a destination;

wherein said specified representation conversion program is configured for execution by a computer at said destination to convert said response from a first representation thereof to a second representation thereof.

19. The computer program product of claim 18 wherein the representation conversion program is stored at a location identified in a header of the response.

20. The computer program product of claim 19 wherein the header uses a message-digest value of an applet to uniquely identify a representation conversion program.

21. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism for converting data from a first representation to a second representation in a network environment, comprising:

logic code for receiving a request from at least one client;

logic code for specifying at least one directive statement in a response to said request; and

logic code for sending said response to a destination;

wherein said response can be converted by a computer at said destination from a first representation thereof to a second representation thereof in accordance with said at least one directive statement.

22. The computer program product of claim 21 wherein the at least one directive statement provides the computer with information related to at least one of foreground portions of an image and background portions of an image.

23. A computer program product for use in conjunction with a computer system, the computer program product comprising a computer readable storage medium and a computer program mechanism embedded therein, the computer program mechanism for converting data from a first representation to a second representation in a network environment, comprising:

logic code for receiving a response to a request from a server, said request having been sent by at least one client to said server;

logic code for determining at least one directive statement from said response; and

logic code for executing said at least one directive statement to convert said response from a first representation thereof to a second representation thereof.

24. The computer program product of claim 23 further comprising logic code that defines policies to decide when to convert the response from the first representation to the second representation.

25. The computer program product of claim 24 wherein the policies are based at least one factor selector from the group consisting of capabilities of a display device and computation time to convert the response from the first representation to the second representation.