Network image view server using efficient client-server, tiling and caching architecture

• US 6,510,459 B2
• Filed: 01/29/2001
• Issued: 01/21/2003
• Est. Priority Date: 02/12/1997
• Status: Expired due to Term

• Current Assignee: ePlus Capital, Inc. (ePlus Incorporated)
• Original Assignee: Digital Paper Corp. (ePlus Incorporated)
• Inventors: Hornbaker, Cecil V. III, Cronin, John C III
• Primary Examiner(s): Sheikh, Ayaz
• Assistant Examiner(s): Zia, Syed
• Application Number:
  US09/770,392
• Publication Number:
  US 20010032238A1
• Time in Patent Office: 722 Days
• Field of Search: 709/203, 709/219, 709/200, 707/10, 707/2, 707/102
• 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: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface

Abstract

A computer network server using HTTP (Web) server software combined with foreground view composer software, background view composer software, a view tile cache, view tile cache garbage collector software, and image files provides image view data to client workstations using graphical Web browsers to display the view of an image from the server. Problems with specialized client workstation image view software are eliminated by using the Internet and industry standards-based graphical Web browsers for the client software. Network and system performance problems that previously existed when accessing large image files from a network file server are eliminated by tiling the image view so that computation and transmission of the view data can be done in an incremental fashion. The view tiles are cached on the client workstation to further reduce network traffic. View tiles are cached on the server to reduce the amount of view tile computation and to increase responsiveness of the image view server.

Claims

1. A method of identifying and delivering a graphical image from a computer network file server, the network file server adapted to store at least one digital document image file and adapted to receive a request for a view from a computer in Uniform Resource Locator (URL) code, the method comprising:

identifying an image file and format selection from a requested view, the format comprising an operation code for selecting an updated view and view template for determining the presentation of the view;

in response to receiving the view request and identifying the image file and format selection, retrieving the digital document image file and composing the requested view into a grid of view tiles corresponding to the requested view of the image; and

computing and transmitting HTML code for the grid of view tiles to the requesting computer.

2. The method as claimed in claim 1 wherein the view request identifies the image file, tile number within the image file, format comprising one or more of position, scale, rotation angle, x mirror, y mirror, inversion, region, operation code to select an updated view, and view template to determine the presentation of the view.

3. The method as claimed in claim 2 wherein the transmitted HTML code for the view tiles causes the requesting computer to display the requested view of the requested graphical image in the requested format.

4. The method as claimed in claim 2 wherein an array of view tiles selected from the grid of view tiles to fulfill the view request is computed by the network file server and transmitted over the network to the requesting computer in HTML and an image file format.

5. The method as claimed in claim 4 wherein the network file server creates an HTML output file listing the size, position, and hyperlink for each view tile to be displayed.

6. The method as claimed in claim 4 wherein the view tiles are stored in an image file format for each view tile for display by the requesting computer.

7. The method as claimed in claim 6 wherein the image file format is at least one of GIF, JPEG, PNG, and TIFF format.

8. The method as claimed claim 1 wherein at least one view tile adjacent to the array of view tiles transmitted to the requesting computer is computed by the network file server during a time period subsequent to the transmission of the array of view tiles, and the adjacent view tile is stored on the network file server.

9. The method as claimed in claim 8 wherein in response to a view request for a view tile adjacent to a previously transmitted array of view tiles, the network file server transmits the subsequently computed adjacent view tile.

10. The method as claimed in claim 2 wherein the requesting computer is adapted to cache received view tiles, and in response to generation of a view request including one or more cached view tiles, retrieving one or more cached view tiles.

11. The method as claimed in claim 2 wherein the view tiles are 128 pixel by 128 pixel image files.

12. The method as claimed in claim 2 wherein the view tiles are 256 pixel by 256 pixel image files.

13. The method as claimed in claim 2 wherein the view tiles are 512 pixel by 512 pixel image files.

14. The method as claimed in claim 2 wherein each view tile is identified by the server with a unique URL which includes storage location and view tile naming data.

15. The method as claimed in claim 2 wherein the position is at least one of absolute, relative, and implied.

16. The method as claimed in claim 14 wherein the view tile naming data includes a view scale.

17. The method as claimed in claim 1 wherein the network file server includes a Web server implemented with Web server Common Gateway Interface (CGI).

18. The method as claimed in claim 1 wherein the requesting computer is configured to run applets or scripts to improve communication with the network file server to reduce the amount of transmitted data.

19. The method as claimed in claim 1 wherein the requesting computer and network file server are adapted to minimize the amount of redundant data transmitted to the requesting computer from the network file server.

20. The method as claimed in claim 1 wherein higher resolution images are sampled by the network file server to transmit lower resolution images to the requesting computer.

21. The method as claimed in claim 1 wherein monochrome gray scale, or color image files are stored on the network file server and transmitted to the requesting computer.

22. The method as claimed in claim 1 wherein non-raster image files are rasterized by the network file server.

23. The method as claimed in claim 1 wherein image files are stored on a second server and retrieved and temporarily stored by the network file server when needed.

24. The method as claimed in claim 1 wherein the requesting computer includes at least one of a workstation, a notebook computer, a palm-top computer, a network computer, and a web television adapter.

25. The method as claimed in claim 1 wherein the image file includes at least one of a raster image format and a non-raster image format.

26. The method as claimed in claim 25 wherein the raster image format includes at least one of a monochrome raster image, a grayscale raster image, and a color raster image.

27. The method as claimed in claim 25 wherein the non-raster image format includes at least one of an Adobe Portable Document Format (PDF), an Adobe PostScript (PS) format, and a Hewlett-Packard Graphics Library (HPGL) format.

28. A method of identifying and delivering a graphical image from a computer network file server, the network file server storing digital document image files, the method comprising:

receiving requests from a Web browser in Uniform Resource Locator (URL) code;

identifying the image file and format selections being requested;

composing the requested view into an array of view tiles; and

transmitting HTML code for view tiles to the requesting Web browser;

wherein view tiles adjacent to the array of view tiles transmitted to the Web browser to fulfill the request described by the URL are computed by the server during a time period subsequent to the transmission of the array of view tiles, and the adjacent view tiles are stored in cache form on the server in anticipation of future requests from the Web browser; and

wherein the view tiles adjacent to the array of view tiles transmitted to the Web browser are computed by the server in a clockwise or counterclockwise spiral sequence outward from the array of view tiles transmitted.

29. A method of identifying and delivering a graphical image from a computer network file server comprising providing a network file server on which are stored digital document image files, said server adapted to receive requests from a Web browser in Uniform Resource Locator (URL) code, to identify the image file and format selections being requested, to compose the requested view into a grid of view tiles, and to transmit HTML code for view tiles to the requesting Web browser;

wherein the URL view request identifies the image file, tile number within the image file, formats comprising one or more of position, scale, rotation angle, x mirror, y mirror, inversion, region, opcode to select an updated view, and view template to determine the presentation of the view, and wherein the transmitted HTML code for the view tiles causes the requesting Web browser-to display the requested view of the requested graphical image in the requested format;

wherein each view tile is identified by the server with a unique URL which includes storage location and view tile naming data;

wherein the URL includes identification data for each scale of view through the file name for each view tile; and

wherein view tiles are named in the format V<

SCALE>

<

TILE_NUMBER>

.<

IFF>

wherein <

SCALE>

value is a 2 character string formed from the base 36 encoding of the view scale number as expressed parts per 256.

30. A method of identifying and delivering a graphical image from a computer network file server comprising providing a network file server on which are stored digital document image files, said server adapted to receive requests from a Web browser in Uniform Resource Locator (URL) code, to identify the image file and format selections being requested, to compose the requested view into a grid of view tiles, and to transmit HTML code for view tiles to the requesting Web browser;

wherein the URL view request identifies the image file, tile number within the image file, formats comprising one or more of position, scale, rotation angle, x mirror, y mirror, inversion, region, opcode to select an updated view, and view template to determine the presentation of the view, and wherein the transmitted HTML code for the view tiles causes the requesting Web browser to display the requested view of the requested graphical image in the requested format;

wherein each view tile is identified by the server with a unique URL which includes storage location and view tile naming data;

wherein the URL includes identification data for each scale of view in the file name for each view tile;

wherein the tile number is encoded in the file name for each view tile;

wherein the image file format is specified in the file name for each view tile;

and wherein view rotation angle, view x-mirror, view y-mirror and invert view information is encoded in the URL naming format in the form V<

SCALE>

<

TILE_NUMBER>

<

VIEW_ANGLE>

<

X_MIRROR>

<

Y_MIRROR>

<

INVERT>

.<

IFF>

wherein VIEW_ANGLE is of the form A<

ANGLE>

; and

X_MIRROR, Y_MIRROR, and INVERT are encoded by the single characters X, Y, and I, respectively.

31. Apparatus comprising:

a computer network server adapted to store digital document image files and programming to receive a view request in Uniform Resource Locator (URL) code, the URL specifying a view which identifies an image file and format selection, the format comprising operation codes for selecting an updated view and view template for determining the presentation of the view;

in response to receiving the view request and identifying the image file and format selection, to retrieve the digital document image file and compose the requested view into a grid of view tiles; and

to compute and transmit HTML code for the resultant grid of view tiles.

32. The apparatus as claimed in claim 31 wherein the server is programmed with Web server software and a foreground view composer adapted to interpret the view request, compute a grid of view tiles of the image, compute an array of view tiles needed for the requested view, to compose the array of view tiles needed for the requested view, and to create an HTML output file to describe the view composition.

33. The apparatus as claimed in claim 31 wherein the server is programmed with a background view composer adapted to compute and cache, during periods between view requests, view tiles surrounding the most recent view request in the same scale as the most recent view so that when a new, shifted view is subsequently requested, the server program computes which of the resultant cached surrounding view tiles are used in response to the request for a shifted view, and composes a view including or more of the cached view tiles.

34. An apparatus comprising:

a network computer for issuing view requests in URL code and displaying received HTML code in response to the view request issuance, wherein the URL specifies a view identifying an image file and format and the HTML code specifies an array of view tiles.

35. The apparatus as claimed in claim 34 wherein the network computer is programmed to cache view tiles received in response to a view request and to access the cached view tiles when included within an array of view tiles included in a subsequent view request.

36. The apparatus as claimed in claim 35 wherein the network computer is programmed with a view tile cache garbage collector for removing the least recently accessed view tiles when maximum storage allocation or minimum storage free space limits are reached.

37. An apparatus comprising:

a computer network server for storing digital document image files, programmed (a) to receive a request from a computer in URL code, the URL specifying a view identifying an image file and format, (b) to compose the requested view, and (c) to transmit HTML code for the composed view to the requesting computer;

and wherein the surrounding view tiles are computed by a background view composer in a clock-wise or counter-clockwise spiral out from the most recent composed view.