AU765488B2 - Multiple document layout - Google Patents

Description

S&F Ref: 529024

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT

ORIGINAL

Name and Address of Applicant: Actual Inventor(s): Address for Service: Canon Kabushiki Kaisha 30-2, Shimomaruko 3-chome, Ohta-ku Tokyo 146 Japan Lena Qian and Julian Benjamin Kelsey Spruson Ferguson St Martins Tower 31 Market Street Sydney NSW 2000 Multiple Document Layout Invention Title: ASSOCIATED PROVISIONAL APPLICATION DETAILS [33] Country [31] Applic. No(s) AU PQ4800 [32] Application Date 22 Dec 1999 The following statement is a full description of this invention, including the best method of performing it known to me/us:- 5815c MULTIPLE DOCUMENT LAYOUT Technical Field of the Invention The present invention relates to printable documents and, in particular, to the creation and layout of printable documents including source material obtained from a number of electronic document sources.

Background Most word processor applications, desktop publishing software and Internet browser applications are configured to handle one document at a time. In most cases where it is possible for the application to open multiple documents simultaneously, for example in Microsoft Word (trade mark) manufactured by Microsoft Corporation, it is only possible to print the multiple documents one at a time. The desktop publishing package FrameMaker (trade mark) manufactured by Adobe Systems Inc. has the facility to print multiple documents consecutively in the single print job by compiling those documents together. This is similar to a traditional batch print job, well know in some operating systems such as UNIX. However, FrameMaker and other batch processes provide no print preview of the multiple document layout.

WebRecord (trade mark) is an Internet printing and management software ::::*application marketed by Canon Inc. having the capacity to source multiple documents from the Internet and then layout those multiple documents as a single printable document described by a print list, in which each source document forms a print item within the print list. The printable document is typically an electronic document configured for printing. The order in which documents are presented in the print list is the order in which those documents are reproduced in the printable document derived therefrom.

WebRecord provides a facility to interactivity alter the order and number of print documents in the print list.

529024.doc -2- Typically, each source document, or print item as used herein, is laid out into the printable document individually thereby retaining zone structural render command references isolated from other source documents within the printable document. The layout structure is retained ready for rendering. Such layout structure maintains an array of sub-pages or columns containing rendering commands.

In Fig. 1, a display pipeline 100 used in prior art arrangements for generating printable documents is outlined. The pipeline 100 includes a first parsing step 102 where the content of the items to be printed are reviewed to identify various components thereof and operators acting upon those components. This for example, may include information regarding placement of images, formatting and the stylising of text. Other processes performed by parsing include the correction of erroneous HTML mark-up, particularly in those instances where a source document is obtained from the Internet, the integration of cascading style sheets, and the like. The information returned by parsing is used by layout step 104 that determines the locations on the printable pages of the various components to be printed. The layout step 104 is typically the most computationally intense component of the pipeline 100. The layout step 104 creates the render commands for a rendering step 106 which actively places the specific visible components of the items into the printable pages. The render step 106 thus forms a series of commands that enable the direct printing of the document or of the page as laid out or alternatively the display of the document on a video display in, for example, a print preview format.

Traditional arrangements for implementing the pipeline 100 require that each time an alteration is made to any aspect of a printable document it is necessary for the entirety of the pipeline 100 to be re-performed, this entailing each of parsing, layout and render. This can be time consuming and computationally intensive, particularly since the layout step is performed on each occasion.

529024.doc -3- It is an object of the present invention to substantially overcome, or at least ameliorate, one or more of the above mentioned difficulties.

Summary of the Invention The difficulties associated with the prior art arrangements are addressed through assessing the type of alteration being made to the document and using such assessment to determine how far back along the display pipeline processing must be taken in order to implement the alteration to the printable document.

According to a first aspect of the present disclosure, there is provided a method of rendering a single printable document comprising at least plural source print items, the method comprising the steps of: parsing a print list to determine a content of said printable document derived from said plural source print items; (ii) laying out said content according to a result of said parsing said print list; 15 (iii) rendering said content into said printable document according to said layout; receiving a request for modifying at least one of said print list, or one of said source documents; examining said modification to determine which of steps (ii) or (iii) 0, 20 needs be performed; and repeating at least those steps in order up to and including step (iii).

0 According to a second aspect of the present disclosure, there is provided a *method of processing a print list for the reproduction of a printable document, said printable document being formed by parsing, laying out, and rendering individual print items that collectively form said printable document, said method comprising the steps of: 529024.doc -4identifying at least one of said individual print items from said list requiring alteration; (ii) examining a type of alteration being proposed to said at least one individual print item to determine a consequential alteration to said printable document; (iii) determining a minimum set of processes of said laying-out and rendering required to give effect to said alteration, said minimum set of processes comprising one or more of parsing, laying out and rendering; and (iv) implementing said minimum set of processes to provide said altered document.

According to another aspect of the present disclosure, there is provided an apparatus for implementing any one of the aforementioned methods.

According to another aspect of the present disclosure there is provided a computer program product including a computer readable medium having recorded thereon a comput er program for implementing any one of the methods described above.

Brief Description of the Drawings One or more embodiments of the present invention will now be described with reference to the drawings, in which: Fig. I schematically depicts a display pipeline used in document reproduction systems; Fig. 2 shows a print list for the creation of a printable document; Fig. 3 schematically illustrates a number of pages of two electronic documents intended to form a single printable document; Fig. 4A is a representation of a printable document formed from the sources of Fig. 3; and 25 Fig. 4B is a representation of part of another printable document formed from the sources of Fig. 3; 529024.doc Fig. 5 is a schematic block diagram of a general purpose computer upon which the arrangements described herein can be practiced; Fig. 6 depicts the various options available for the selecting the type of layout change; Fig. 7 depicts the actions consequential to Fig. 6; Figs. 8A to 8C depict the maintenance of a layout structure for two-column page formatting; and Fig. 9 is a flowchart of preferred processing of a document to account for changes in content and/or presentation.

Detailed Description including Best Mode The principles of the methods described herein have general applicability to computerised document generation. However, for ease of explanation, the steps of the preferred method are described with reference to Web printing applications configured for operation on the World Wide Web (WWW). However, it is not intended that the present invention be limited to the described methods.

The preferred embodiment provided a modified implementation of the layout manager 120 which, as seen in Fig. 1, operates in concert with each of the members of the display pipeline 100 so as to maintain track of the layout structure of the printable document and to calculate the position of each render command on the printing page at rendering time.

Fig. 2 shows a display list of a preferred printable document to be rendered in accordance with one embodiment of the present invention. The display list includes a table of contents 202 listing the contents of a printable source items, those being Item #1 204 and Item #2 206, also seen in the print list 200. As seen from Fig. 3, Item #1 comprises three sub-pages within the printable document, the first two of which are fully 529024.doc -6occupied by content, and a third sub-page (sub-page 2) having content occupying approximately three quarters of the page. Item #2 is also seen in Fig. 3 and spans two sub-pages one of which is fully occupied and the second of which is one quarter full.

Fig. 4A shows one arrangement of printable pages 400 formed from the print list 200 in which content of the print list is reproduced in two columns 402 and 404 spread amongst each of three individual pages 406, 408 and 410. The printable pages 400 can also include page decoration items such as header 412 and footer 414 which are permanently prescribed for each page to be produced and which are laid out and rendered during the render phase 106. As seen from Fig. 4A, the table of contents occupies the first column 402 of the first printable page 406 and the contents of Item #1 follow thereafter filling the next two and three quarter columns and ending on printable page 408. Item #2 directly follows Item#l and occupies the next one and a quarter columns, ending at the end of the first column 402 of the third printable page 410.

The layout manager 120 also controls re-laying out and re-render of the print 15 items within the print list 200. The layout manager 120 operates in the following way.

Where a new item is to be laid out individually without affecting other items in the print list 200, the new item is merely added to the print list whereupon a parse step 102 and layout 104 of that new item need be performed and its rendering added to the render list.

As a consequence, for those items already existing in the print list, is not necessary to re- 20 parse, re-layout or re-render those items, since the addition of the new item does not influence their reproduction.

Further, where items within the print list 200 are rearranged, it is not necessary for any of those items to be re-laid out if the internal organisation of each item is remains unchanged. This may occur where, for example, Item #2 is to precede Item In such a 529024.doc -7situation, only the rendering step of the print pipeline 100 need be re-performed in order to provide the revised reproduction according to the altered print list.

The fuill parse/layout pipeline of the documents is required only when the content of the individual items is changed. This occurs for example when items within a component source document are altered thereby affecting the manner in which that document is laid out internally and hence the manner in which other documents are laid in association with the document which has been altered. An example of where such a re-laying out is necessary is where the layout of a Web page, previously visited by a user, has changed between visits.

An example of alteration where re-layout is not required is that shown in Fig. 4B with pages 422 and 424 of document 420 corresponding to pages 408 and 410 of Fig. 4A.

In Fig. 4B3, it is desired for Item #2 to commence the new column of the printable document 420. This is achieved merely by forcing Item #2 to start at the next column thereby leaving vacant space at the end of the column in which Item #1 terminates, as seen on revised printable pages 422 and 424. Such a re-arrangement does not involve a re-laying out of Item but rather merely the re-rendering of those pages from the document 400.

When a document is merely created, at rendering time, the layout manager 120 20 initially performs a full rendering for all printable items by processing through each layout structure. When a new item is appended to the print list 200, only the new layout 6% structure needs to be rendered. If there are any changes for an item, as numbered n in the list, rendering is only required from the last page of item number through to the remainder of the list. In some implementations, only the page decorations are required during the partial rendering. For instance, if an item is deleted from the print list, the rest of the pages can remain unchanged excepting that the page numbers need to be re- 529024.doc -8rendered. For example, if an item occupies pages 4, 5 and 6 of a document (ie. 3 pages), and the item is then deleted, all pages in the document after page 6 must be re-rendered with the original page number minus 3.

It follows from the above that a number of optimised processes within the pipeline are available to be performed depending on the type of document editing that occurs in order for the desired document to be reproduced. Fig. 6 shows the variations available for a particular layout type, those being no change, partial layout, partial render, full layout and full render. Figs. 7 illustrates the operation of layout manager 120 where a group of one or more changes 122 being made to the printable document are received and a check 124 is performed as to the type of re-layout or re-render to be performed. This is seen in the method 900 of Fig. 9 where the method 900 commences at step 902 and the user selects at step 904 a change to the document to be reproduced. Step 906 then performs a check of the change. Returning to Fig. 7, where the check 124 results in either a partial re-render 128 or a partial re-layout 126, each is processed only for those items in 15 the printable document affected by the change. Alternatively, a full re-render 130 or a full re-layout 132 is performed. There are three types of changes.

A first type of change as seen in Fig. 9 at step 908 comprises attribute changes on print items, the selection of the which are summarised in Table 1 below, which 20 implements to operations of step 910.

TABLE 1 0000 0 Layout Type Changes One or a Set of Items All Items set text to black partial render full render -set background on/off partial render full render set image plane holder on/off partial render full render item header/footer on/off partial layout partial full layout and full 529024.doc render render change font size partial layout and partial fuill layout and full render render The output of Table 1 (step 910) is a layout type that is provided at step 912.

The second type are attribute changes on printable pages and are depicted as step 914 in Fig. 9. Such changes include colun number, page orientation, page header and footer, and some of which necessitate a full layout and full render, and others need a partial render, as shown in Table 2 below with respect to step 915. Again the output of this step is a layout type provided at step 912.

TABLE 2 Changes Layout Type .:*Column Number Full Render Page Orientation Full Layout and Render :Page Header Partial Render Page Footer Partial Render Initial Page Number Partial Render 10 The third type of changes occur when items are deleted from or added to the printable document, this being seen as step 916 in Fig. 9. A test is performed at step 918 to determine the change to be implemented. If items are started from the beginning of a sub-page (ie. Fig. 4B), the rules for processing such changes are: Step 920: Append an Item partial layout of Item and partial render of Item 529024.doc 10 Step 922: Insert an Item -+partial layout of Item and partial render of Items Step 924: Delete an Item ->partial render of Items Again the output of these changes are a layout type at step 912. The layout structure is based on the dimensions of the printable page but is independent of any content of the page, this being represented in Fig. 8. Thus, the layout structure may used to render either on-screen, or to a printer, of any desired resolution. Different scaling factors are used to scale the rendering command on the device upon which rendering is to take place. Such a partial layout and rendering approach can improve the performance of printable generation, particularly in cases where there are many print items, most particularly when those items involve numerous data types such as text, images and formatting changes and the like.

As seen from Fig. 9, the method 900 concludes with step 926 where a check for re-layout or re-render is performed again according to Fig.7.

6 e 1 Figs. 8A to 8C depict a method of maintaining the layout structure of an :**tooelectronic document 800 having three pages 802, 804 and 806 appropriately numbered in &Sootheir respective lower right hand corner, and each having information formatted into two columns on each page. Each item within the printable document 800 is formed with a corresponding layout structure seen in Fig. 8B. During the rendering step, additional information may be described using the notation shown in Fig. 8C and summarised 0 0 6below, which describes where various parts of an item have been positioned within a sets document.

Logical Page Physical Page sub-page lID P n r 1 ci 529024.doc -1lwhere 0 i m, m pages for the item, ni= page number o <ri <ROWNUM 0 ci COLNUM ni, ri, and ci show the position of the sub-page in the document.

Given: Initial-Subpage ID (ISID) (no x ROWNUM x COLNUM) for Pni (ro x COLNUM) co r i c i The subsequent position of a sub-page can be calculated for sub-page as: ni (ISID i) (ROWNUM x COLNUM) ri =(ISID i) /COLNUM Ci (ISID i) COLNUM.

With the initial sub-page position, the remainder of the sub-pages can be located accordingly, for a partial render.

The layout manager of the preferred embodiment offers a variety of document :editing functions that permit accelerating the rendering of the desired results, and thus the editing process. For example, where it is desired to create a single printable document having inputs from, say, twelve source items, those source items may be merged linearly, one after the other, into the printable document. If it were desired to create a summary of 20 the entire printable document, a first column of each of the source items may be extracted 0: from the first component of the printable document, and be followed by the remaining columns of each of the twelve items in turn. In accordance with the preferred embodiments, once the original document is laid out, each of the first columns of the source items may be accessed and re-rendered without a need to perform a re-laying out of each of those components. Re-rendering of those components of the source items 529024.doc -12results in the simple placement of those components into pages of the printable document as opposed to the re-organisation of the content thereof.

The printable document layout methods described above are preferably practiced using a conventional general-purpose computer system 500, such as that shown in Fig. wherein the methods may be implemented as software, such as an application program executing within the computer system 500. In particular, the laying out steps of the method are effected by instructions in the software that are carried out by the computer.

The software may be divided into two separate parts; one part for carrying out the restructuring methods, and another part to manage the user interface between the latter and the user. The software may be stored in a computer readable medium, including the storage devices described below, for example. The software is loaded into the computer from the computer readable medium, and then executed by the computer. A computer readable medium having such software or computer program recorded on it is a computer program product. The use of the computer program product in the computer preferably 15 effects an advantageous apparatus for restructuring HTML documents sourced from the Internet in accordance with the embodiments of the invention.

.i The computer system 500 comprises a computer module 501, input devices such as a keyboard 502 and mouse 503, output devices including a printer 515 and a display •o device 514. A Modulator-Demodulator (Modem) transceiver device 516 is used by the computer module 501 for communicating to and from a communications network 520, for example connectable via a telephone line 521 or other functional medium. The modem 516 can be used to obtain access to the Internet, and other network systems, such as a Local Area Network (LAN) or a Wide Area Network (WAN).

The computer module 501 typically includes at least one processor unit 505, a memory unit 506, for example formed from semiconductor random access memory 529024.doc 13 (RAM) and read only memory (ROM), input/output (110) interfaces including a video interface 507, and an 1/0 interface 513 for the keyboard 502 and mouse 503 and optionally a joystick (not illustrated), and an interface 5 08 for the modem 5 16. A storage device 509 is provided and typically includes a hard disk drive 510 and a floppy disk drive 511. A magnetic tape drive (not illustrated) may also be used. A CD-ROM drive 512 is typically provided as a non-volatile source of data. The components 505 to 513 of the computer module 501, typically communicate via an interconnected bus 504 and in a manner which results in a conventional mode of operation of the computer system 500 known to those in the relevant art. Examples of computers on which the embodiments can be practised include IBM-PC' s and compatibles, Sun Sparcstations or alike computer systems evolved therefrom.

Typically, the application program of the preferred embodiment is resident on the hard disk drive 510 and read and controlled in its execution by the processor 505.

Intermediate storage of the program and any data fetched from the network 520 may be accomplished using the semiconductor memory 506, possibly in concert with the hard :disk drive 5 10. In some instances, the application program may be supplied to the user encoded on a CD-ROM or floppy disk and read via the corresponding drive 512 or 511, or alternatively may be read by the user from the network 520 via the modem device 516.

Still further, the software can also be loaded into the computer system 500 from other computer readable medium including magnetic tape, a ROM or integrated circuit, a magneto-optical disk, a radio or infra-red transmission channel between the computer module 501 and another device, a computer readable card such as a PCMCIA card, and the Internet and Intranets including e-mail transmissions and information recorded on Websites and the like. The foregoing is merely exemplary of relevant computer readable 529024.doc 14 media. Other computer readable media may be practiced without departing from the scope and spirit of the invention.

Industrial Applicability It is apparent from the above that the embodiment(s) of the invention are applicable to the computer and data processing industries, and in particular to computer network browsing software applications having a printing capability.

The foregoing describes only one embodiment of the present invention, and modifications and/or changes can be made thereto without departing from the scope and spirit of the invention, the embodiments being illustrative and not restrictive.

In the context of this specification, the word "comprising" means "including principally but not necessarily solely" or "having" or "including" and not "consisting only of'. Variations of the word comprising, such as "comprise" and "comprises" have corresponding meanings.

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Claims (3)

1. 2. A method according to claim 1, wherein when step (iv) comprises receiving a request for adding an item to an end of said print list, step causes step (ii) to be performed only on said item and step (iii) on said item and an immediately preceding item in said list.
2. 3. A method according to claim 1, wherein when step (iv) comprises receiving a request for modifying one of said source print items and step comprises re-laying out said one source print item, said re-rendering comprises re-rendering said one source print item and each subsequent said source print item in said print list.
3. 529024.doc -16- 4. A method of processing a print list for the reproduction of a printable document, said printable document being formed by parsing, laying out, and rendering individual print items that collectively form said printable document, said method comprising the steps of: identifying at least one of said individual print items from said list requiring alteration; (ii) examining a type of alteration being proposed to said at least one individual print item to determine a consequential alteration to said printable document; (iii) determining a mimimum set of processes required to give effect to said consequential alteration, said minimum set of processes comprising one or more of parsing, laying out and rendering; and (iv) implementing said minimum set of processes to provide said altered document. oO.o oooo 5. A method according to claim 4 wherein a re-laying out of at least part of said printable document necessitates re-rendering said part and remaining parts of said document. 6. A method according to any one of the preceding claims wherein a modification and consequential processing of said printable document is determined according to a plurality of types of change, wherein: a first type of change comprises attribute changes on print items, the selection of which is summarised in the Table 1 below; 529024.doc -17- TABLE I Items Changes One or a Set of Items All Items set text to black partial render full render -set background on/off partial render full render set image plane holder on/off partial render full render item header/footer on/off partial layout partial full layout and full render render change font size partial layout and partial full layout and full render render a second type of change comprises attribute changes on printable pages, said attribute changes including changes to column number, page orientation, page header and footer, summarised in Table 2 below; TABLE2 r Changes Layout Type Column Number Full Render Page Orientation Full Layout and Render Page Header Partial Render Page Footer Partial Render Initial Page Number Partial Render r a third type of type of change which occurs when items are deleted from or added to said printable document, each said item starting at a beginning of a sub-page, in 10 which said third type of changes are defined by: append content to an item requiring a partial layout of item and a partial render of item 529024.doc -18- (ii) insert an item requiring a partial layout of item and a partial render of items and (iii) delete an item requiring a partial render of items 7. A method according to any one of the preceding claims wherein at least one of said print items is sourced from an electronic communication network, such as the Internet. 8. A method according to any one of the preceding claims wherein at least one of said print items is formed according to Hypertext Mark-up Language (HTML). 9. A method according to claim 8 wherein said one print item comprises hyperlinks. 15 10. A method of processing a print list substantially as described herein with reference to Figs. 1 to 7 of the drawings. 11. Apparatus for performing the method of any one of the preceding claims. 12. A computer system for performing the method of any one of claims 1 to 13. A computer readable medium comprising a computer program product incorporating a plurality of instructions for performing the method of any one of claims 1 to r 529024.doc -19- 14. A computer readable medium comprising a computer program product incorporating a plurality of instructions for rendering a single printable document comprising at least plural source print items, said computer program product comprising: code for parsing a print list to determine a content of said printable document derived from said plural source print items; code for laying out said content according to a result of said parsing said print list; code for rendering said content into said printable document according to said layout; code for receiving a request for modifying at least one of said print list, or one of said source print items; code for examining said modification to determine which of said parsing, laying out or rendering needs be further performed. 15. A computer readable medium according to claim 14, wherein when said o "receiving a request for modifying comprises receiving a request for adding an item to an V. end of said print list, said examining causing said laying out to be performed only on said item and said rendering on said item and an immediately preceding item in said list. 16. A computer readable medium according to claim 14, wherein when said S receiving a request for modifying comprises receiving a request for modifying one of said source print items and said examining comprises re-laying out said one source print item, i: said re-rendering comprises re-rendering said one source print item and each subsequent said source print item in said print list. 529024.doc w^ ^i,-3iA^ *l lax 20 17. A computer readable medium comprising a computer program product incorporating a plurality of instructions for processing a print list for the reproduction of a printable document, said printable document being formed by parsing, laying out, and rendering individual print items that collectively form said printable document, said computer program product comprising: code for identifying at least one of said individual print items from said list requiring alteration; code for examining a type of alteration being proposed to said at least one individual print item to determine a consequential alteration to said printable document; code for determining a minimum set of processes required to give effect to said alteration, said minimum set of processes comprising one or more of parsing, laying out and rendering; and code for implementing said minimum set of processes to provide said altered document. A computer readable medium according to claim 17 wherein a re-laying out of at least part of said printable document necessitates re-rendering said part and remaining parts of said document. 20 19. A computer readable medium according to any one of claims 14 to 18 wherein a modification and consequential processing of said printable document is determined according to a plurality of types of change, wherein: a first type of change comprises attribute changes on print items, the selection of which is summarised in Table 1 below; 529024.doc -21- TABLE 1 Items Changes One or a Set of Items All Items set text to black partial render full render -set background on/off partial render full render set image plane holder on/off partial render full render item header/footer on/off partial layout partial full layout and full render render change font size partial layout and partial full layout and full render render a second type of change comprises attribute changes on printable pages, said attribute changes including changes to column number, page orientation, page header and footer, a selection of which is summarised in Table 2 below TABLE 2 .00. Changes Layout Type Column Number Full Render Page Orientation Full Layout and Render Page Header Partial Render Page Footer Partial Render Initial Page Number Partial Render ;and a third type of type of change which occurs when items are deleted from or added to said printable document, each said item starting fr~om a beginning of a sub-page, 10 in which said third type of changes are defined by: append content to an item requiring a partial layout of item and a partial render of item 529024.doc -22- (ii) insert an item requiring a partial layout of item and a partial render of items and (iii) delete an item requiring a partial render of items 20. A computer readable medium according to any one of claims 14 to 19 wherein at least one of said print items is sourced from an electronic communication network, such as the Internet. 21. A computer readable medium according to any one of claims 14 to 20 wherein at least one of said print items is formed according to Hypertext Mark-up Language (HTML). 22. A computer readable medium according to claim 21 wherein said one print item comprises hyperlinks. .23. A computerised system for rendering a single printable document comprising at least plural source print items, said system comprising: means for parsing a print list to determine a content of said printable document derived from said plural source print items; means for laying out said content according to a result of said parsing said print list; **means for rendering said content into said printable document according to said layout; means for receiving a request formodifying at least one of said print list, or one of said source print items; 529024.doc -23- means for examining said modification' to determine which of said parsing, laying out or rendering needs be further performed. 24. A system according to claim 23, wherein when said means for receiving a request for modifying adds an item to an end of said print list, thereby causing said laying out to be performed only on said item and said rendering on said item and an immediately preceding item in said list. A system according to claim 23, wherein when said means for receiving a request for modifying modifies one of said source print items and said means for examining comprises re-laying out said one source print item, said re-rendering comprises re-rendering said one source print item and each subsequent said source print item in said print list. too. i1 26. A computerised system for processing a print list for the reproduction of a U. printable document, said printable document being formed by parsing, laying out, and rendering individual print items that collectively form said printable document, said system comprising: means for identifying at least one of said individual print items from said list requiring alteration; veto means for examining a type of alteration being proposed to said at least one individual print item to determine a consequential alteration to said printable document; to.. :660 means for determining a minimum set of processes required to give effect to said alteration, said minimum set of processes comprising one or more of parsing, laying out and rendering; and 529024.doc 24 means for implementing said minimum set of processes to provide said altered document. 27. A system according to claim 26 wherein a re-laying out of at least part of said printable document necessitates re-rendering said part and remaining parts of said document. 28. A system according to any one of claims 23 to 27 wherein a modification and consequential processing of said printable document is determined according to a plurality of types of change, wherein: a first type of change comprises attribute changes on print items, the selection of which is summarised in Table 1 below; 000. **so. 000 0 0 0 @0 *0000 a Osets TABLE 1 Items Changes One or a Set of Items All Items set text to black partial render full render -set background on/off partial render full render set image plane holder on/off partial render full render item header/footer on/off partial layout partial full layout and full render render change font size partial layout and partial full layout and full render render 529024.doc a second type of change comprises attribute changes on printable pages, said attribute changes including changes to column number, page orientation, page header and footer, a selection of which is summarised in Table 2 below, TABLE 2 I Changes Layout Type Column Number Full Render Page Orientation Full Layout and Render Page Header Partial Render Page Footer Partial Render Initial Page Number Partial Render and a third type of type of change which occurs when items are deleted from or added to said printable document, each said item starting from a beginning of a sub-page, in which said third type of changes are defined by: append content to an item requiring a partial layout of item and a 10 partial render of item (ii) insert an item requiring a partial layout of item and a partial render of items and (iii) delete an item requiring a partial render of items 29. A system according to any one of claims 23 to 28 wherein at least one of said print items is sourced from an electronic communication network, such as the Internet. A system according to any one of claims 23 to 29 wherein at least one of said print items is formed according to Hypertext Mark-up Language (HTML). 529024.doc I I r^r.*l I YI ~C i -26- 31. A system according to claim 30 wherein said one print item comprises hyperlinks. DATED this second Day of July, 2003 CANON KABUSHIKI KAISHA Patent Attorneys for the Applicant SPRUSON&FERGUSON 529024.doc ~;r*r~rixEir~:i rjir~.l'r~i~ ir~-rrilirrr~i~ iv~iii=ily