Abstract:
Access to an electronic version of a physical work is provided to a user. The electronic version of the physical work comprises images of the physical work that, when visually displayed, appear the same as the physical work. Access to the electronic version of the physical work is based on user ownership of the physical work. Access to a portion or all of the physical work may be provided in accordance with one or more access rules. A user may own a physical work by virtue of purchasing the physical work or purchasing an item that the physical work normally accompanies. A flag may be set for later reference to indicate user ownership of the physical work.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of application Ser. No. 10/750,166, titled METHOD AND SYSTEM FOR ACCESS TO ELECTRONIC IMAGES OF TEXT BASED ON USER OWNERSHIP OF CORRESPONDING PHYSICAL TEXT, filed Dec. 31, 2003, which is a continuation of application Ser. No. 10/669,088, titled PERSONALIZED SEARCHABLE LIBRARY WITH HIGHLIGHTING CAPABILITIES, filed Sep. 23, 2003, and application Ser. No. 10/668,690, titled METHOD AND SYSTEM FOR SUPPRESSION OF FEATURES IN DIGITAL IMAGES OF CONTENT, filed Sep. 23, 2003 (now U.S. Pat. No. 7,149,353), and incorporated herein by reference. 
    
    
     BACKGROUND 
     The information age has produced an explosion of content for people to read. This content includes traditional media such as books, magazines, newspapers, newsletters, manuals, guides, references, articles, reports, documents, etc. that exist in print, as well as electronic media in which the aforesaid works are provided in digital form. The Internet has further enabled an even wider publication of content in the form of document downloads, such as portable document files and e-books. 
     Given the vast sea of content that people encounter, it is not uncommon for a person to read something and later recall a memorable phrase or subject, but not remember the exact source of the phrase or subject. The person may attempt to obtain recently read items in an effort to find the phrase or subject, but searching these items in this manner can be tedious, time consuming, and unfruitful. A person may also simply wish to research a particular subject in a set of books or other content that the person owns, has read, or is otherwise aware of. 
     Separately, various search engines have attempted to catalogue Web pages available on the Internet. However, given the enormous amount of content published electronically on the Internet, searching the entire Internet for a phrase or subject in a particular source the reader recently read can be similar to finding a needle in a haystack. The reader may have to wade through pages and pages of search results provided by search engines, and in the end, may still be unable to locate the desired source. Moreover, the desired source may not have been published on the Internet in the first place, and thus would not be included in this type of search. 
     Electronic searching of public library catalogs is also known, but such searching is limited to bibliographic information and other meta-information that describe the library content. Full text searching of public library content is not available, and even if it were, the search may produce results from sources that are not of interest to the user. 
     Moreover, a user owning a physical work may wish to have access to an electronic version of the physical work (e.g., via a networked computer system), wherein the electronic version of the physical work appears the same as the physical work. Existing systems have not provided users with the ability to access such electronic versions of physical works based on the users&#39; ownership of the physical works. U.S. Pat. No. 6,609,105 describes a system designed specifically to allow users to listen to electronic versions of music stored on compact discs, DVD&#39;s, cassette tapes, or records. However, provision of electronic music (e.g., via data streaming) presents a different set of challenges, and hence a different set of solutions, than providing a user with access to electronic versions of physical works that are visually displayed. What is needed, in at least one aspect, is a method and apparatus that can process a user&#39;s request to access an electronic version of a physical work, determine the user&#39;s ownership of the physical work, and provide access to the electronic version of the physical work based on the user&#39;s ownership of the physical work. 
     BRIEF SUMMARY 
     The following description briefly summarizes certain aspects of the disclosure herein. This summary is not intended to identify all features or embodiments disclosed herein, nor is it intended to identify key features or otherwise be used to define the scope of the invention claimed hereafter. 
     A user may be provided access to an electronic version of a physical work based on ownership of the physical work. In one aspect, a computer-implemented method is provided in which a user request for access to an electronic version of a physical work is processed. Electronic versions of physical works are stored in a data storage. The electronic versions of the physical works comprise images of the physical works that, when visually displayed to the user, appear the same as the physical works. The method determines whether the user owns the physical work, and if the user is determined to own the physical work, the user is then provided with access to the electronic version of the physical work. 
     User ownership of a physical work may be determined based on purchase information pertaining to the user indicative of whether the user has purchased the physical work. In that regard, the method may further include communication with a third party regarding the purchase information of the user. Alternatively, user ownership may be confirmed by receiving a receipt from the user evidencing purchase of the physical work. In yet another alternative, the user may provide an image of a portion of the physical work to confirm ownership of the work. Access rules consulted as part of the method may permit user access to an electronic version of the entire physical work when ownership of the work is confirmed. 
     Another embodiment is directed to a computer system that includes a data storage, a communications component, and a processing component. The data storage contains electronic versions of physical works that, when visually displayed, appear the same as the physical works. The communications component is configured to communicate with a user. The processing component is configured to process a request received from the user via the communications component to access an electronic version of a physical work stored in the data storage. The processing component determines whether the user owns the physical work, and if so, then provides the user with access to the electronic version of the physical work. 
     In yet another embodiment, a computer-readable medium containing executable program instructions may be provided for execution by a computing apparatus. The program instructions, when executed, are configured to provide user access to an electronic version of a physical work based on user ownership of the physical work. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a pictorial diagram showing an environment for implementing one exemplary embodiment of the invention; 
         FIG. 2  is a block diagram depicting an arrangement of certain computing components for implementing the embodiment shown in  FIG. 1 ; 
         FIG. 3  is a flow diagram describing one embodiment of a process for preparing images of content and storing the images in a page image database, along with preparing and storing text of the content in a text searchable database; 
         FIG. 4  is an example illustration of a page of content with text and a picture; 
         FIG. 5  illustrates the page shown in  FIG. 4  with identified text shown in boxes; 
         FIG. 6  illustrates a substitute page in which images of the text identified in  FIG. 5  are copied and placed in the substitute page, thus effectively suppressing the picture in the original page shown in  FIG. 4 ; 
         FIG. 7  is a flow diagram describing one embodiment of a process that enables a user to select and add content to be included in the user&#39;s personalized library; 
         FIG. 8  is a flow diagram describing one embodiment of a process for searching and displaying content in the user&#39;s personalized library; 
         FIG. 9  depicts a browser program with an example Web page presenting a search input field to a user; 
         FIG. 10  depicts a browser program with an example Web page presenting results of a sample search; 
         FIG. 11  depicts a browser program with an example Web page showing an image of a page from a selected search result; and 
         FIG. 12  depicts a browser program with a Web page as shown in  FIG. 11  in which the search result is highlighted in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  illustrates one environment for implementing an embodiment of the present invention. The environment shown includes a library content search system  100  with an electronically-searchable library of content that can be personalized by multiple individual users. The environment also includes various electronic user devices, such as a computer system  102  and a PDA  104 , that individual users can use to communicate with the search system  100 . In the environment shown in  FIG. 1 , the user devices  102 ,  104  communicate with the search system  100  via one or more computer networks, such as the Internet  106 . Protocols and components for communicating via the Internet are well known to those of ordinary skill in the art of computer network communications. Communication between user devices  102 ,  104  and the search system  100  may also be enabled by local wired or wireless computer network connections. 
     The search system  100  depicted in  FIG. 1  operates in a distributed computing environment comprising several computer systems that are interconnected via communication links, e.g., using one or more computer networks or direct connections. However, it will be appreciated by those of ordinary skill in the art that the system  100  could equally operate in a computer system having fewer or greater number of components than are illustrated in  FIG. 1 . Thus, the depiction of the search system  100  in  FIG. 1  should be taken as exemplary, and not limiting to the scope of the invention. 
     The search system  100  as illustrated includes a search server  108 , a database server  110 , and a back-end interface  112 . Each of the servers  108  and  110  are described below in more detail. The back-end interface  112  allows an operator of the search system  100  to monitor and adjust the operation of the servers  108  and  110  as needed. 
     In brief, the search server  108  is generally responsible for providing front-end user communication with various user devices, such as devices  102  and  104 , and back-end searching services in cooperation with the database server  110 . The front-end communication provided by the search server  108  may include generating text and/or graphics, possibly organized as a Web page using hypertext transfer protocols, in response to information and search queries received from the various user devices  102 ,  104 . The search server  108  also is generally responsible for conducting searches of the databases in the database server  110 . The database server  110 , as described below, maintains the databases that the search server  108  uses to respond to user search queries. 
     In one suitable implementation provided herein to illustrate an embodiment of the invention, the search system  100  enables a user to review an index that catalogs the general library of content in the databases stored in the database server  110 . This general library of content may include various forms of publications, including (but not limited to) books, magazines, newspapers, newsletters, manuals, guides, references, articles, reports, documents, etc. To facilitate user review and selection of content from the general library, various metadata may be associated with the content in the general library. This metadata may include internal attributes, such as title, author, subject, abstract publisher, publication date and place, publication type, characters, etc. External attributes may also be associated with the content, such as sales popularity, user reviews, publisher promotion, related media, events, etc. The index that catalogs the general library may be organized and presented to the user according to one or more of these attributes. 
     In this embodiment of the invention, the user may select the content from this general index of content to be included or otherwise associated in a personalized library for the user. The content in the user&#39;s personalized library, or “personal library,” is electronically-searchable in all respects, thus enabling the user to search the full text of the content for specified terms (e.g., words, phrases, graphics, charts, pictures, or other text or non-text objects). Depending on access rights and permissions granted to the user, the results of a search may include some, all, or none of the full-text content in which the specified terms are found. Images of one or more pages of content that include the search terms are delivered by the search server  108  to the user device  102 ,  104  for display to the user, e.g., in the form of a Web page, a portable document image, a raster-based image, a vector-based image, etc. Images of content may be stored and delivered in .jpg, .gif, and/or .tif formats, for example. The search terms as found in the image display may also be highlighted by the user device  102 ,  104  in accordance with the present invention, as described later herein. 
     Selection of content to include in a user&#39;s personal library can be accomplished in a variety of ways. For example, a user may manually select content from a general library of content in a manner that specifically identifies the content that the user desires to include in his or her personal library. Automated selection of content based on other user actions may also be provided. For example, each time the user selects particular content for review or for purchase, that content may be added automatically to the user&#39;s personal library. Similarly, a content review or purchase history received from one or more sources may be used to automatically add content to the user&#39;s personal library. 
     As will be discussed below, a personal library enables a user to define and search a particular set of content. Preferably, the user establishes a personal library prior to executing a search so that the search algorithm has a limited universe of content on which to act. In other circumstances, a personal library may be established in real time with the submission or execution of a search query or after the search has been executed on some broader library to define the scope of search results that are presented to the user. 
       FIG. 2  illustrates certain exemplary computing components that are responsible for the operation of the library content search system  100  shown in  FIG. 1 . The search server  108 , for example, is shown including an operating system  114  that provides executable program instructions for the general administration and operation of the search server  108 . The search server  108  further includes computer program instructions for implementing a search engine  115  that operates in cooperation with the database server  110  to respond to user search queries. Suitable implementations for the operating system  114  and algorithms for the search engine  115  are known or commercially available, and are readily implemented by persons having ordinary skill in the art, particularly in light of the disclosure herein. 
     The database server  110 , as illustrated in  FIG. 2 , includes a page image database  116 , a text searchable database  118 , and an access rights database  120 . The database server  110  is configured to receive search instructions from the search engine  115  and return search results from the page image database  116  and/or text searchable database  118 . The access rights database  120  enables the search server  108  to control the scope and nature of the content that can be displayed to the user as a result of a search. For example, a user may be permitted to view an entire image of a page of content, such as a book, that the user already owns. For content not owned by the user, the user may be permitted to view only a selected portion of the page image located by the search, with the remaining portions of the page image being suppressed. Those of ordinary skill in the art will recognize that the search server  108  and database server  110  will typically employ a memory and main processor in which program instructions are stored and executed for operation of the servers. The database server  110  further includes executable program instructions for maintaining and updating the databases  116 ,  118 , and  120 , and responding to search instructions received from the search engine  115 . 
     For the sake of convenience, much of the description herein is provided in the context of searching the content of books, but it should be well understood that the present invention is applicable to searching a library containing other forms of content that can be read and displayed to a user. References herein to specific types of content, such as books, magazines, newspapers, etc., are only illustrative and do not serve to limit the general application of the invention. 
     In one aspect, the present invention is directed to searching a library of content that is personalized by a user. A user&#39;s personalized library, or “personal library,” includes only such content as selected by the user, either manually or automatically as a result of one or more user actions. In order to provide content that the user can select to include in his or her personal library, it is appropriate (though not required) to first create a general library of content. In one implementation of the invention discussed herein, libraries of content include both images of pages of content, as well as text searchable forms of the content. Page images are stored in the page image database  116 , while searchable text corresponding to the page images is stored in the text searchable database  118 . Further embodiments of the invention may allow a user to upload and store page images that are specific to the user&#39;s personal library. When permissible, the user may also add the uploaded content to the general library of content for selection by other users. 
     One embodiment of a process  122  by which pages of content can be prepared and stored in the databases  116  and  118  is shown in  FIG. 3 . For each page of content to be included in the general library (from which different users&#39; personal libraries may be defined) or in a user&#39;s personal library, images of each page of the content are acquired, as indicated at block  123 . Image acquisition can be performed using methods known in the art, such as scanning printed pages, converting electronic text to document images, retrieving page images from memory, etc. 
     For each page of content, a recognition routine, such as an optical character recognition (OCR), may be performed on the page image as necessary to identify the text, position, and size of each word on the page, as indicated in block  124 . It should also be understood that a “word” encompasses any grouping of one or more characters, numbers, or symbols. Moreover, a word may stand alone or be associated with a non-text object, such as a picture or graphic. OCR routines are well known in the art of electronic document processing and do not require further discussion herein. As indicated at block  125 , the resulting text, position, and size information obtained from each page image is preferably stored in the text searchable database  118 . 
     The text searchable database  118  may be organized as desired, preferably using data structures optimized for full text searching. In one suitable embodiment, each word in the text searchable database  118  has associated therewith content identification numbers (e.g., SKU numbers) and page numbers corresponding to images in the page image database  116  where the particular word is found. Furthermore, in association with each page image number, the text searchable database  118  preferably includes information that identifies the position and size of the text (and possibly non-text objects associated with the text) as found on the respective page image. In one implementation, the position and size information is recorded as “quads,” which include four numbers representing the X and Y position and the width and height of the text as it appears on a particular page image. All of this information may be heavily encoded in the text searchable database  118  to reduce the storage space required. 
     A general library of content or personal library of content may be configured to include only that content for which the library owner has obtained valid rights to store, reproduce and distribute the content. Situations may arise in which a publisher of a book, for example, grants rights to a library owner to store and reproduce certain features as found in a book, but restricts the reproduction of one or more other features in the book, e.g., for copyright or contractual reasons. Such features may include, for example, photographs, graphics, charts, names, numbers, dates, formulae, equations, pictures, and other text or non-text objects, or portions thereof. Features may also be characterized by size, font, and/or location on a page image. For whatever reason the case may be, a process is provided in which features in a page image can be suppressed so that when the page image is displayed to a user (e.g., as a result of a search), only the non-suppressed features of the page image are displayed. 
     At decision block  126  in  FIG. 3 , the process  122  determines for a page image whether the page has one or more features to be suppressed. If no features need to be suppressed, the originally-acquired page image is stored in the page image database  116 , as indicated at block  127 , for later retrieval. 
     On the other hand, if one or more features in a page image are to be suppressed, the process  122  proceeds to extract the non-suppressed features in the page image, as indicated at block  128 , in order to prepare a substitute image that omits the features to be suppressed. One example of feature extraction in this regard is described in reference to  FIGS. 4-6 . The resulting substitute page image is then stored in the page image database  116  in place of the originally-acquired page image, as indicated at block  127 . In some circumstances, it may be permitted to separately store the original page image in anticipation of later receiving rights to reproduce more or all of the original page, including previously suppressed features. Alternatively, it may be permitted to store a “negative” version of the page image in which the non-suppressed features are removed, but all else (including the suppressed feature) remains. The original page image can be restored in this alternative case by combining both the “positive” and “negative” versions of the page image. 
       FIGS. 4-6  illustrate one exemplary process by which a feature (here, a picture) in a page image can be suppressed.  FIG. 4  depicts a page image  136  that includes both text  138  and a picture  140 . A first task in this process is to identify each word on the page image  136 , as well as the location and size of each word. Conveniently, this can be achieved as part of the OCR process described earlier with respect to block  124  in  FIG. 3 . OCR approximation can also be used in this regard, which is often faster and can be conducted in real time as opposed to typical OCR where each character of each word is independently and correctly recognized. OCR approximation returns the location and size of words, but does not necessarily recognize each individual character correctly.  FIG. 5  illustrates the page image  136  in which each of the words on the page have been located and identified, as represented by the boxes surrounding each word indicated by reference numeral  142 . The word indicated at numeral  144  has also been located and identified, but the word  144  is separately noted herein because the background of the word includes a small portion of the picture  140 . 
     Turning to  FIG. 6 , a substitute image  145  for the page image  136  is prepared by generating a blank image and then copying information for each identified word, such as pixel information, from the original page image  136  to the substitute image  145 , as indicated generally by reference numeral  146 . The words are placed on the substitute image  145  at the respective location that each word is found in the original image  136 . By “cutting” only the pixel information for each word as contained in the boxes surrounding the words in  FIG. 5 , and “pasting” the pixel information in the substitute image  145 , the picture  140  in the original image  136  is effectively suppressed. When the pixel information for the word image  144  is copied into the substitute image  145 , as shown at reference numeral  148 , the small part of the picture behind the word  148  may remain visible in the substitute image  145 , though the picture  140  as a whole cannot be recognized. If desired, algorithms known in the art may be applied to the word image  144  to eliminate the background behind the letters. In any case, the amount of the picture  140  behind the word  148  represents only a small fraction of the original picture  140 . In an alternative embodiment, a substitute image that suppresses a picture may be prepared by first identifying words in the original page image  136 , e.g., as shown in  FIG. 5 , and then “erasing,” or removing, all the pixel information in the page image outside the “boxes” that surround the identified words. The effect is the same as cutting and pasting the word images into a new (substitute) page image. 
     In some cases, the original page image  136  may have a background texture or color that is desired to be reproduced in the substitute image  145 . One suitable method for preparing a substitute image  145  with a background similar to that of the original image  136  is to inspect one or more pixels in one or more corners of the original image  136  and reproduce the color and intensity of those pixels in the respective corners of the substitute page  145 . The color and intensity from each corner may then be interpolated inward to the center of the page to complete a background for the substitute page  145  that simulates the background of the original image  136 . In the alternate embodiment above, where pixel information outside the “boxes” is “erased,” the pixel information may be differentiated between foreground pixel information and background pixel information with only the foreground pixel information being erased, leaving the background information in its place. 
     Feature suppression can vary depending on the type of content involved and the restrictions imposed. For example, a publisher of a recipe book may allow an ingredient list for a recipe to be shown to a user but not the amount of ingredients. Using OCR techniques, numbers such as “5” and “five,” for example, can be identified and suppressed, as well as fractions, using one of the feature suppression methods described above. Allowing a user to see an ingredient list (and perhaps the cooking instructions) allows the user to identify desirable recipes. The user may then seek to acquire the entire recipe, e.g., by electronic download or printed recipe book purchase. Similar procedures may be used by publishers of technical treatises or texts where numbers and/or equations are central operative features of the texts. Although the numbers and equations may be suppressed, the user is afforded an opportunity to view surrounding text and at the same time may be invited to purchase the text to view the operative numbers or equations. Different classes of information may thus be suppressed from the page images that are stored in the page image data base  116  and/or shown to the user. Suppression of a picture, as illustrated in  FIGS. 4-6 , is just one example of a class of information capable of suppression. Feature suppression may be performed prior to storing a (substitute) page image in the page image database or after retrieval of a page image from the database but before the page image is displayed to the user. 
     Turning now to  FIG. 7 , a process  150  is described by which a user may establish or update a personal library of content that is selected from a general library of content, as stored in a page image database  116  and text searchable database  118 . As a first step  152  in the process  150 , the user selects content from the general library and includes this content (or electronic link thereto) in the user&#39;s personal library. By way of example only, the content described in  FIG. 7  is in the form of a book, though the invention applies to other forms of content. As discussed earlier, in one embodiment, user-selection of content for a personal library may be accomplished by permitting the user to review an index of the content in the general library and manually select particular content (in this example, a book) to include in the user&#39;s personal library. For each selection at block  152 , the process  150  determines at a decision block  154  whether the user owns the book. If the user does not own the book, the particular book is identified as non-owned by the user, as indicated at block  156 , and added to the user&#39;s personal library, as indicated at block  158 . Non-ownership of a book in a user&#39;s personal library may be indicated by an electronic flag associated with the book in the personal library. 
     Returning to decision block  154 , if the user indicates that he or she owns the book, the process  150  attempts to confirm the user&#39;s ownership. In circumstances where the personal library searching service is provided by an entity that sells books, the entity may review its purchase information for the user to confirm that, in fact, the user owns the book, as indicated at reference numeral  160 . The personal library searching service may also have partner agreements with other booksellers that can confirm purchase records for a user. Reviewing the user&#39;s purchase records may further be done automatically for books selected by the user in block  152 , without querying the user whether he or she owns the book. Alternatively, a user&#39;s selection of a book for purchase may act to automatically add the book to the user&#39;s personal library. In any regard, if the user&#39;s purchase of the book is confirmed, the process  150  proceeds to add the book to the user&#39;s personal library, as indicated at block  158 . A flag may be associated with the book in the personal library to indicate that ownership of the book has been confirmed. After a book (or other content) has been added to the user&#39;s personal library, the user may choose to store the personal library in a computer memory for later retrieval. If desired, the search system  100  may be configured to allow a user to establish and/or update multiple personal libraries in the computer memory. 
     If ownership of the book cannot be confirmed by reference to a purchase record or other data source for validation of ownership, the process  150  may ask the user to undergo additional steps to validate ownership of the book, as indicated at block  162 . The user, for example, may be asked to submit copies of receipts evidencing purchase of the selected book. Alternatively, or in addition, the user may be asked to provide an image of one or more pages from the selected book to validate ownership of the book. In some circumstances, it may be sufficient for the user to indicate the party from whom the book was purchased, and the provider of the personal library searching service can independently confirm with the identified seller that in fact a purchase of the book had been made. A determination of ownership of content selected for a personal library is not critical or necessary to the invention, but is helpful in circumstances where the amount and scope of content displayed to a user in a search is restricted in accordance with established ownership of the content. 
     As noted earlier, the database server  110  may include an access rights database  120  that controls the scope and nature of the content that is displayed to a user as a result of a search. The access rights database  120  includes access rules that, when determined to be applicable, act to limit the content in the page images that are shown to the user. Limitations on viewing content may be established for each individual user (or groups or types of users), and may include, but are not limited to, one or more of the following: limits on the amount (e.g., percentage) of content that can be shown to the user for any given page, title, or collection of content, limits on the total number of pages that can be shown for any given title or collection of content, limits on the amount of content based on type of content, limits on the total number of pages that can be shown to a user independent of content-specific limitations, and limits on the total number of pages that can be shown to the user for any given search result. These limits may be imposed on a per search basis or in the aggregate for all of the searches conducted by the user. These limits may also be imposed for specified time periods. For example, access rules may be written such that a user may not see more than a specified percentage of a given page of content in a specified time frame, such as a 30-day time period, or 10 days in a 30-day cycle, or over the lifetime of the user. 
     Access rules may also serve to define the amount of content that can be provided to the user based on an identification of the user. A log in or registration routine may be employed to identify a user. The library content search system  100  may implement user verification procedures to inhibit users from establishing multiple accounts to circumvent access limitations in the access rights database  120 . For example, entry of a valid credit card number may be required for verification of user identification. The search system  100  may further be set up to permit users to view content that is located only as a result of a search. In other words, the user is not permitted to access and view arbitrary pages, for example, in a browse mode (though the user may be able to browse one or more pages adjacent a page located in a search to give context to the located page). To carry out limitations such as these, the search system  100  may be configured to track user activity for each user, including the identity of the page images (or portions thereof) that the user has viewed and the time frame in which the user has viewed the page images. 
     Access rules in the access rights database  120  may further be configured to apply differently for each individual user (or groups of users) depending on content-specific information, such as the type of content at issue. For example, access rules may be written to permit unlimited viewing of tables of content and indexes of content but impose stricter limitations on viewing the body of the content itself. 
     User location can also act as a factor that determines which access rules govern a user&#39;s access to content at the time the content is produced for display to the user. For instance, different access rules may be written to enable a student in a classroom to access an entire body of content that is being used in the class, while the same student, at home, is only able to view a limited portion of the content. The domain of computer connection, for example, may be used to determine user location. Access rules may be written to apply differently based on the time the content is to be provided to the user, e.g., on different days or at different times of day, as well. Access rules may also be prepared and stored in the access rights database  120  so that once a portion of a page image has been displayed to a user, the user can always come back to view that portion, without impacting other limits on viewing new page images. In any event, the access rules may be written in programming code that a computer can interpret and execute to implement the access rules. Systems for writing and executing such code are known in the art of computer programming. 
     The personal libraries of users need not duplicate the actual content stored in the general library. Rather, each user&#39;s personal library may be comprised of a listing of the content that the user has selected from the general library to include in his or her personal library. This personal listing of content may link to the actual content stored in the database server  110 . By limiting the number of actual copies of the content in the database server  110 , and allowing users&#39; personal libraries to link to that content, the amount of storage space required for implementing a personal library searching service is reduced. Furthermore, providing a general library of content that is publicly accessible to users for defining personal libraries reduces or removes from users the burden of scanning content and creating searchable electronic copies of content for their personal libraries, not to mention obtaining legal clearance to produce copies of content, where such is necessary. 
     A user that has established and/or updated a personal library is able to electronically search the personal library, e.g., for content having text that matches one or more search terms provided by the user. A search conducted in this manner has significant advantages including (1) limiting the user&#39;s search to the particular content in the user&#39;s personal library; (2) conducting a full text search that encompasses the entire body of content in the user&#39;s personal library which is more comprehensive than a search encompassing only bibliographic and abstract data or metadata associated with the content; and (3) producing for immediate review by the user the actual images or portions of images of content resulting from the search. Additional advantages are evident from the description herein. 
     One embodiment of a process  170  for searching and viewing content in a personal library is described in reference to  FIG. 8 , with further reference to  FIGS. 9-12 . In  FIG. 8 , at block  172 , a user initiates a search for specified text in the content in the user&#39;s personal library. In a Web-based implementation, one example of a Web page provided to the user for searching a personal library is illustrated in  FIG. 9 . 
       FIG. 9  illustrates a browser program  200  displaying a Web page in which the user is able to enter one or more search terms in a search entry box  202 . The Web page may be generated by the search server  108  and delivered to the user&#39;s computing device  102 ,  104  via the Internet. The user enters the desired search terms in the box  202  and uses a pointing device, keyboard, or other input device to initiate the search, e.g., by clicking on the button “GO” identified at reference numeral  204 . The Web page in  FIG. 9  may include other hypertext links, such as an “Index” link  206  and “Frequently Accessed Titles” link  208 , both providing additional information that can be assembled into one or more additional Web pages not illustrated. Clicking on the Index link  206  for example, may produce a Web page for the user that lists bibliographic data for all of the content presently included in the user&#39;s personal library. The Frequently Accessed Titles link  208  may produce, for example, a listing of the content most frequently accessed by the user. 
     Log in and log out routines may be employed by the search server  108  to provide users with secure access to their personal libraries. Suitable routines for verifying a user requesting access to a personal library (e.g., using a password) are well known in the art. In  FIGS. 9-12 , it is assumed the user has already logged in. A Log Out link  210  is illustrated and, when initiated, enables the user to discontinue the user&#39;s current session and log out of his or her account. 
     Returning to  FIG. 8 , at block  174 , the search server  108  receives the user&#39;s specified search terms and initiates a search of the text searchable database  118  to identify the pages of content in the user&#39;s personal library that include the text of the search query. As noted earlier, the text searchable database  118  is preferably constructed to include information that identifies the corresponding images in the page image database  116  where the search terms can be found. Thus, when conducting a user search for specified terms, the text searchable database  118  not only identifies the particular content in the user&#39;s personal library that contains the specified text, but also identifies the corresponding page images in the page image database  116 . 
     The results of the user&#39;s search performed in block  174  are displayed to the user, as indicated at block  176 .  FIG. 10  illustrates the browser program  200  displaying a Web page in which search results for a sample phrase “riddle of the sphinx” are shown at reference numeral  212 . The search results  212  may be displayed in a variety of different formats. By way of example only, the search results  212  in  FIG. 10  include a listing of title and author, as indicated at reference numeral  214 , along with thumbnail images of the content, or portion thereof (such as a book cover), as indicated at reference numeral  216 . Again, the search results  212  are generated from a search of the content selected by the user to be included in the user&#39;s personal library. In cases where there are numerous search “hits” in the user&#39;s personal library, the search server  108  may execute program instructions that analyze the hits and rank the “best” pages for display to the user according to a predetermined criterion, such as which pages are most relevant. Measures of relevance, for example, may include which pages have the most hits, which pages have hits in their title, which pages are drawn from best selling texts, etc. 
     Returning to  FIG. 8 , at block  178 , the user may select particular content in the search results, e.g., identified by title and/or page number, for additional review. The search server  108  may immediately display images of the user-selected content to the user. However, in the embodiment shown in  FIG. 8 , the search server  108  at block  180  first reviews the access rights database  120  in the database server  110  to determine whether there are any access rules governing how much of, or even if, the content listed in the search results can be displayed to the user. As previously discussed, the access rights database  120  is a repository for rules that control the ability of users to access and view the actual content in the library, e.g., beyond standard bibliographic information. 
     For instance, as noted earlier, different rules may be written to govern a user&#39;s access to content that is already owned by the user, as opposed to content not owned by the user. For user-owned content that is identified in the search results, the user may be permitted to access the entire body of that content including page images that precede or follow the pages on which the user&#39;s search terms are located. This includes, for example, operating manuals for products that the user has purchased. 
     For content that the user does not own, one or more rules in the access rights database  120  may act to limit the amount of content surrounding the located search terms that may be displayed to the user. For example,  FIG. 11  illustrates a browser program  200  displaying a Web page for a particular title in the search results previously communicated to the user, such as shown in  FIG. 10 . The title of the search result, indicated at reference numeral  220 , may be any of those in the search results  212 , for example. 
     A sample page image  222  from the selected result title  220  is depicted in  FIG. 11 . The page image  222 , in this instance, is an image of “page 17” from the result title  220  but does not include all of the content of the original page image. This redaction, or suppression, of content can be the result of a circumstance in which a user has limited access rights to the actual content of the result title  220 . In this example, based on a search for the phrase “riddle of the sphinx” as shown in  FIG. 10 , the resulting page image  222  shows the actual page where the phrase “riddle of the Sphinx” is found, along with a limited number of words preceding and following the search terms. All other words and features on the page image  222 , except for the page number, are suppressed. The number of words preceding and following the located search terms may vary according to user preferences and the access rules governing the particular content for the user. In this illustration, nine words are shown preceding and following the phrase “riddle of the Sphinx.” In other circumstances, the access rules in the access rights database  120  may permit the user to view a greater portion or even the entire image of “Page 17” (i.e., page image  222 ) in  FIG. 11 . Methods for feature suppression described earlier may be used to suppress content in the page image to be displayed in accordance with the access rules in the access rights database. 
     In short, returning to  FIG. 8 , after a user has selected particular content from the search results  212  (block  178 ) and the access rights to the content have been considered (block  180 ), the image of one or more pages with text corresponding to the search terms are retrieved from the page image database (block  182 ). Based on the access rights granted to the user, a portion or all of a retrieved page image is displayed to the user (block  184 ). 
     Optionally, search terms specified by a user may be highlighted in the page images displayed to the user, as indicated at block  186 . The present invention provides a process by which search terms may be highlighted in a manner that reduces the time and resources required for delivering the page image to the user for display. 
     Rather than formatting a page image  222  with highlighting of search terms at the search server  108  and then delivering the highlighted page  222  to the user, an embodiment of the present invention may proceed to immediately deliver the page image  222  to the user. In the meantime, the search server  108  determines the position and size of the search terms on the page image  222  (information that may be available in the text searchable database  118  as discussed earlier) and delivers that information to the user. The user device  102 ,  104  may then locally execute program instructions to place a visual indicator on the page image  222  to highlight the location of the search terms. The visual indicator may be an icon placed next to or an underline placed under the search terms. Alternatively, the visual indicator may be a change of font of the search terms as displayed. In a preferred embodiment, the visual indictor is provided by one or more blocks of transparent color that overlay the search terms, thus creating the effect of a colored highlight  224  ( FIG. 12 ) when the page image  222  is displayed. In the latter preferred embodiment, the user device  102 ,  104  may be instructed to use DHTML layering or Java script technology to cause the user device  102 ,  104  to produce the highlight  224  on the page image  222 . By having the user device  102 ,  104  prepare and overlay the color highlight on the search terms, the only information that the search server  108  needs to communicate to the user device  102 ,  104  (as to highlighting) are the numeric “quads” for each word to be highlighted. As noted earlier, a quad is a set of four numbers that describes the X and Y position as well as width and height of a word on a particular page image. In another embodiment, only the X and Y position of search terms is communicated and a highlight of a standard thickness is layered over the search terms. Minimizing the amount of information that the search server  108  needs to communicate to the user device  102 ,  104  will reduce the amount of time that it takes to communicate from the search server  108  to the user device  102 ,  104 . 
     A user&#39;s personal library can also be divided as desired into classes of works, such as fiction and nonfiction works, and within such classes, subdivided into subclasses such as mystery, adventure, history, reference, etc. Classes and subclasses of works may be predefined or customized by the user. By restricting searches to particular classes or subclasses of books in the user&#39;s personal library, the searches performed by a user may be more focused and helpful to the user. For example, a medical student may define a personal “medical” library in which full text searches of medical texts in the student&#39;s personal library are conducted. Furthermore, an algorithm that identifies “related” text may also be used to aid a user&#39;s selection of content for the personal library to include content that may not be strictly classified in a particular class but nonetheless be related to a class that the user desires to search. “Related text” algorithms are known in the art and may use dictionary definitions and synonyms of certain words, for example, to identify related content to include in the personalized library that is searched. 
     While preferred embodiments of the invention have been illustrated and described above, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. For example, the notion of a personal library may be extended from a single person to a small group of persons (constituting a “user”), that know each other and choose to pool the content that they own. A small group of this type may be comprised of family members or persons living in the same apartment or in the same fraternity, etc. Each person in the group can determine the content to be included in the group&#39;s personal library. A single searchable set of content is provided to the group. The search results may also be configured to report who in the group owns the book and who currently is in possession of the book. 
     The description of searching “text” herein can be extended to include searching non-text objects as well, such as pictures, graphs, etc. Searching non-text objects can be accomplished by searching data, such as visible text (e.g., legends or labels), hidden text, and/or metadata, that is associated with or otherwise describes the object at issue. The text searchable database  118  can be constructed to include such visible or hidden text or metadata, with position and size information pointing to the object in the page image at issue. 
     It should also be understood that providing to the user an image of a page of content does not necessarily imply providing an image having the same dimensions as the original page content. An image of a page of content can be any size and may be adjusted in size to more closely conform to the particular portion of content that the access rules (if any) permit for display. Accordingly, depending on the search terms and the pages of content at issue, a user may receive an image that is only half of the original page, or one paragraph from the page, etc., with the page image being displayed having dimensions that match the portion of the page that is shown. 
     The scope of the present invention should thus be determined, not from the specific examples described herein, but from the following claims and equivalents thereto.