WO2002075593A1

WO2002075593A1 - Digital library for georeferenced maps

Info

Publication number: WO2002075593A1
Application number: PCT/GB2002/001286
Authority: WO
Inventors: Robert James Watts
Original assignee: Digi-Data Technologies Limited
Priority date: 2001-03-17
Filing date: 2002-03-15
Publication date: 2002-09-26
Also published as: GB0106655D0

Abstract

A computer program product is provided for installation into the memory of an individual computer or a network for storage and retrieval of information concerning spatially related articles, and in particular for cataloguing collections of maps and other spatially related articles. The program comprises: computer-readable instructions for causing the computer to maintain a relational database (95) comprising a plurality of records for articles catalogued in the database, each record having a first field set (102) for identity data for the article, a second field (104) set for data defining a storage location for the article and a third field set (not shown) for coordinates within a predefined projection defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system; computer-readable instructions for causing the computer to enter records into the database; and computer-readable instructions for interrogating the database using X and Y coordinates within the geographic location system.

Description

DIGITAL LIBRARY FOR GEOREFERENCED MAPS

FIELD OF THE INVENTION

This invention relates to a computer program product loadable into the memory of a computer for storage and retrieval of information concerning spatially related articles, to a method for creating a database for storage and retrieval of information concerning spatially related articles, to a relational database for use in the storage and retrieval of information concerning spatially related articles, to a method for interrogating the above database to retrieve records relating to a place or area, to a record structure for the database and to a computer or computer network on which a computer program product as aforesaid is installed. The computer program product is particularly, but not exclusively, concerned with the cataloguing or indexing of maps held in collections by libraries, museums, universities or other bodies. It also relates to a method of retrieving an article on the basis of a spatial relationship, the article being a physical article such as a map, photograph or artifact or being an electronically recorded article.

BACKGROUND TO THE INVENTION

The literature on classifying and cataloguing library collections is extensive, and catalogues or indexes for library collections are now routinely held on computer. However, no satisfactory method has yet been proposed for incorporating into a computer-assisted indexing or cataloguing system data relating to a collection of maps and the places where individual maps are to be found. The provision of such a system for maps and other spatially related information is becoming increasingly necessary because of increasing use of library collections by researchers and the general public and because of increasing use of computer networks to exchange information between libraries. US-A-5843373 (De Lorme) discloses a computer aided map location system that provides correlation and coordination of spatially related data between a computer and a set of printed maps. Although various databases are described, they are applied to user location systems, for example GPS.

SUMMARY OF THE INVENTION

In one aspect, the invention provides a computer program product loadable into the memory of a computer for storage and retrieval of information concerning spatially related articles, said program product comprising: computer-readable instructions for causing the computer to maintain a relational database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system; computer-readable instructions for causing the computer to enter records into the database; and computer-readable instructions for interrogating the database using X and

Y coordinates within the geographic location system.

The invention further provides a method for creating a database for storage and retrieval of information concerning spatially related articles, said method comprising entering records into the above database.

In a further aspect, the invention provides a relational database for use in the storage and retrieval of information concerning spatially related articles, said database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system.

The invention yet further provides a method for interrogating the above database to retrieve records relating to a place or area, said method comprising supplying to the database a query that includes at least one pair of X and Y coordinates within the geographic location system. The user may go on to retrieve the article either from a physical location within a collection in the case of a real article or from an electronic address in the case of an article that is recorded electronically e.g. on a magnetic or optical disk of a computer or at an address in a computer network.

The invention further provides a record for a relational database concerning spatially related articles, said record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system.

The invention further provides a computer program product loadable into the memory of a computer for storage and retrieval of information concerning spatially related articles or objects, wherein the program includes instructions for display during storage and retrieval of information of a base map in a predetermined projection, and instructions for cataloguing the articles or objects in a database on the basis of one or more stored X-Y coordinates within the projection and coordinate system of the base map.

The invention further provides a method of retrieving an article on the basis of a spatial relationship, which comprises: providing a relational database which stores and permits and retrieval of information concerning spatially related articles, said database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for coordinates within a geographic location system; displaying a base map; generating a query by selecting at least one point on the base map and supplying to the database a query that includes at least one pair of X and Y coordinates within the geographic location system corresponding to said at least one point; generating a report of articles and their storage locations on the basis of said at least one pair of coordinates; and retrieving at least one article on the basis of its storage location.

Storing information about spatially related objects or articles in a database on the basis of coordinates registered within a geographic location system having e.g. the attributes of projection and a standard grid, and specifying searche queries by means of coordinates within the geographic location system provides a database in which objects are simple to classify and queries are simple and rapid to execute. Furthermore the display in storage and retrieval mode of a so-called base map having the projection and coordinate system in which objects are registered provides a user interface which is intuitive for users and which facilitates rapid and accurate entry of data and queries. It also enables maps in different projections and for different periods to be catalogued in a single database.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention will now be described, by way of example, with reference to the accompanying drawings in which: Fig. 1 shows an opening screen for a cataloguing program according to the invention;

Figs. 2 - 7 show successive screens in a data entry mode of the program; Fig. 8 shows the structure of a record within a database created using the data entry mode of the screens of Figs. 2-7;

Figs. 9 - 19 show successive screens in a database query mode of the program; Fig 20 shows a report produced using the database query mode of the screens of Figs. 9 -19;

Fig. 21 shows a screen of an image viewer facility enabled by the present program

Fig. 22 shows a report produced using the image viewer mode of the screen of Fig 21 ; and

Fig. 23-24 shows a map return dialog screens used to enable the user to locate the correct return point for a particular map.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Nature of the program and hardware requirements

As previously described, the invention relates to a cataloguing program for articles that are related to places on the surface of a planet, most usually the Earth. The articles for which the program can be used will most typically be maps, but they may also include still or moving images related to a particular place, for example paintings, photographs or films related to a particular place, plans of buildings at a particular place, sound recordings related to that place and articles located at or associated with that place. For example, a library or museum located elsewhere in the world but concerned with ships and shipping might have in its collection for Greenwich physical and topological maps of Greenwich, geological and street maps of Greenwich, aerial photographs, copies of historical documents related to Greenwich, plans of the National Maritime Museum at Greenwich, paintings of the museum, a catalogue for the museum, and photographs of the state barges that form part of the collection of that museum. Maps, photographs and other images may be held in the collection as hard copy or as digital cartographic or other data. A user wishing to know what is held in the library or museum collection about Greenwich might be interested in any of these articles, and the present program provides a common means of classifying them by location. The program may be used by anyone such as a librarian or curator who has to maintain a catalogue for a collection of spatially related articles or who wishes to query what is held in the catalogue for a particular place or area, including libraries and museums, public record offices, local authorities, public utilities, companies concerned with the exploitation of oil or mineral resources, and members of the public who are users of the collection to gain access to information held in the collection e.g. for research purposes.

The program can be installed on a single computer, but it will typically be installed on a network server e.g. on an Online Public Access Catalogue (OP AC) server of a library, museum or university, on a file server of e.g. a local authority or on a file server of a company and will be accessible by clients through a local network or through the Internet. Versions of the program may be written for installation under a variety of conventional operating systems including successive versions of Windows, Unix, Linux, and of Apple Macintosh, the version described below being designed to run under Windows 98. The server or other computer on which the present program runs will normally also have installed on it a geographic desktop mapping program, for example Maplnfo Professional 5.5 available from Maplnfo Corporation, One Global View, Troy, New York 12180-8399 USA. That program handles data files in the form of tables and permits data for a graphic objects to be entered once X and Y coordinates have been assigned to them, the table then containing an identity that provides a cross-link to the object. Graphics images, e.g. raster images registered by map coordinates can be displayed as conventional images in a map; alternatively data may be displayed as a tabular list or as a graph.

A further useful facility provided by Maplnfo and other geographic desktop mapping programs is that of geocoding i.e. converting a street address or a post-code into X and Y coordinates within a global or local coordinate system e.g. the National Grid (UK), longitude and latitude (France) or Universal Transverse Mercator (UTM; USA). Geocoding is described, for example, in US- A-6047236 (Hancock et al; GO2 Software Inc) and US-A-6101496 (Esposito; Maplnfo Corporation). Geographers commonly refer to such coordinates as "earth coordinates". Astronomers may wish to catalogue maps of lunar or planetary surfaces; the term "earth coordinates" as used herein covers coordinates on the surfaces of these bodies.

Also normally installed on the server or other computer will be a programming language associated with the geographic desktop mapping program (in the present case MapBasic from Maplnfo Corporation) for writing programs that work in conjunction with it and which will provide database access tools e.g. in a language modeled on the SQL query language for querying a database, applying a filter to screen out unwanted records, sorting the results of a query and carrying out arithmetical and logical operations. MapBasic has the advantage that applications written in that language are portable and can be supplied generally without modification to e.g. Macintosh and Windows users.

Where the present program is installed on a network server, then a program group will need to be installed at each user to enable that user to send queries to the network server and to receive reports. Users querying the program via the Internet will similarly have to have permanent or temporary files for sending queries and receiving reports.

Record structures

The present program is intended to work with one or more relational databases in which the individual records relate to maps or other spatially related articles within a collection. Each record will normally contain at least: • A first field set for identity data for the article and containing least one field. The first field set may, for example contain a first field for an object identifier which may for example be an accession number, a second field for the name of the object and a third field for a class of the object within a classification scheme. The number and purpose of the fields within the first set is, of course, at the discretion of the librarian or curator.

• A second field set for data defining a storage location for the article within the collection and also containing at least one field. In the case of a hard copy map within a map collection, identifiers e.g. numbers or other characters within the field or fields may define a physical storage location, e.g. a press and a bar where the map is held. In the case of a map that is held as a digital record, then a directory path and a file name or a meta-tag may define an electronic storage location.

• A third field set for coordinates that define a place or area of or associated with the article and that include at least one pair of fields for X and Y coordinates within a geographic location system. The number of coordinates for each record varies depending on record type. Where the record concerns a place whose extent within the geographical location system is negligible, e.g. a single building, then for a single pair of X and Y coordinates is sufficient to define its position. Many maps are rectangular and aligned with a coordinate system or grid forming part of the geographic location system, in which case it suffices to provide two pairs of fields for the location of opposite corners of the map. Other maps may be represented by polygons defined by three or more pair of fields. For example, aerial photographs are usually rectangular but are unlikely to be aligned with the geographical location system, in which case the coverage will be defined by the coordinates of the four corners. Older maps may be of irregular shape, e.g. county maps whose boundary traditionally follows that of the county to which they relate and which may be approximated by means of a more complex polygon or may be represented more accurately by means of a shape defined using a drawing tool, the shape then being stored e.g. as coordinates defining a set of adjoining rectangles.

It will be appreciated that each record may contain additional sets of fields depending upon the requirements of particular collections, for example in the case of maps defining the scale and type of the map and the date when it was produced or published. Some or all of such fields may be used to allocate the record to purposely-constructed geographic information system (GIS) catalogue layers, which can be interrogated and viewed separately so that a user can choose which layer or combination of layers to interrogate depending upon the particular demands of an individual search. A layer is distinguished as a separate sub- catalogue that may be stored as an individual file by traditional cartographic variables such as format, scale, series number etc. For example the OS 1 :25,000 Outdoor Leisure Series of maps provides a logical self-contained catalogue layer both from the standpoint of the user and from the standpoint of the custodian. A satisfactory description of the maps held in the map collection of a university library might typically employ about 60 such layers. Employment of a system of separate catalogue layers rather than a single all-inclusive database file enables individual database files to be constructed for each layer and these individual files can be placed on-line and taken off-line for updating when necessary without making other files inaccessible. Once it has been completed or updated, a catalogue layer can be brought on-line, enabling a database search engine to include it in any future enquiry. The search engine acts as a filter, sieving through the individual catalogue layers in order to extract those maps and other articles that match search criteria specified by the user. A typical catalogue layer may defined by:

• A file name, e.g. W. Dorset Ecology, Channel Islands, Postcodes or One Inch Tourist.

• A type, e.g. Administrative, Geological, Hydrological, Physical, Land Use or Special Collections. • A scale

• A series, e.g. NG series, Street Maps, Touring Maps.

• Date last amended.

The data entry mode and its user interface

Referring to Fig. 1, an opening screen 10 presents four options: to enter a data entry mode by clicking on button 12, to enter a catalogue interrogation mode by clicking on button 14, to enter a map return mode by clicking on button 17 or to quit the program by clicking on button 16.

On selection of the data entry mode Fig 2 is displayed which permits entry of new records into the catalogue. Screen 18 has a space 20 for entry of an authorization code, which is submitted by entering a return case on the keyboard. Assuming that the correct code has been entered, the program then displays the screens of Figs 3-7, which provide a user interface permitting the entry of new records. The user interface is designed for non-expert data entry once the interface for a particular collection has been defined and catalogue layers have been constructed.

The first screen 24 provides for selection of a new record for storage within an area or set of layers which is specific to a particular continent, or within additional classifications "World" or "Part of World" which are included to enable data to be entered for world or regional maps. Selection is by scrolling up or down a list that appears in menu space 26 and entering a selection by clicking on a Next button 27. The process of selecting a continent prompts the system to highlight the corresponding continent on the map 29 along with an information panel providing statistics relating to the particular continent.

Figure 4, screen 28, appears and prompts selection of an individual country from within the selected continent by scrolling up or down menu space 30. Again as with the choice of continent, the choice of country prompts the system to highlight the corresponding country on the map 37 along with an information panel providing statistics relating to the particular country. In the same screen, clicking on one of a row of buttons 32 indicates the format of the spatial information required. The window 28 provides buttons for topographic/physical, geology, soil survey, land use, political/administrative, oceanographic, street maps, thematic, aerial photography and special collections, which may give access to a further list or lists (not shown). When the selections have been made, clicking on NEXT button 34 brings about display of screen 36, figure 5, which has a menu space for indication in which of the available scales the data is to be recorded (which correspond to catalogue layers), selection being by scrolling up or down the displayed list and clicking on NEXT button 40. The user can return to any screen by clicking on return buttons 31, 33 and 35 so as to make alterations in his entry criteria.

Figure 6 shows the selected layer on the backdrop of a so-called base map

50 of the whole of the selected country which is shown in a particular projection, e.g. in the UK the National Grid, and which provides a basis for inputting spatial information in the form of X-Y coordinates within that projection. The base map is linked to the objects catalogued in the database because it has the same projection and scale as the spatial information used for cataloging the objects within the database. It makes the present cataloging program easier to use because it enables the user to visualize the information the information that he is entering and also the information that is returned to him in the search mode to be described below. The base map also shows existing maps within the layer for which data has already been entered. To assist navigation, zoom in and zoom out buttons 44, 46 are provided together with a grabber button 48 for repositioning the map 50 in the window. Clicking on any of the tools 52, 54, 88, 90 on the command line opens data entry screen 42, figure 7 in which there is a panel 56 appropriate for the tool selected. A select button 54 is for selection of an object within the window and acts as a default pointer/cursor tool. Four methods are provided for data entry: • Button 52 enables the user to enter known coordinates as characters. Where the corner coordinates of a map to be entered are known, e.g. for ordinance survey maps, a data entry panel 56 has fields 58,60 for the X - Y coordinates of the top left comer of the map and fields 62,64 for the X - Y coordinates of the bottom right corner. When these coordinates have been entered, the computer superimposes marks the position entered (for a single point) or draws an outline of the new map for which data is to be entered so that the user can see whether or not the entry that he has made is what he intended to input. The appropriate coordinates can be entered unto these fields using a computer keyboard. The data entry panel has a field 66 for an identifier which is linked to map type, a field 67 for the name of the map or other article, a field 68 for a code which may be a serial or an accession number, and fields 69 and 70 which display the scale and type which have already been entered at screens 28,36. Further fields for data entry include a date field 72 for the date of making or publication of the map, fields 74,76 for the physical location of the map (assumed to be a hard copy) in terms of the number of the press and the number of the bar where it is stored, and fields 78,80 for entry of the number of copies of the map in the collection and the physical condition of the map for which a record is being entered. Clicking on button 82 enables a user to enter information on any associated digital images that may exist of the original hardcopy map into fields on panel 83. Operation of key 86 cancels the entry and operation of key 84 causes the entry to be recorded in the database.

• Button 88 enables the user to enter coordinates for the map to be recorded by using a rectangle drawing tool on the displayed national map. By graphically defining the locational coordinates of the map to be recorded in this way causes the data entry fields 58-64 to be unavailable. The computer automatically generates the X-Y coordinates of the top left and bottom right corners of the rectangle which has been drawn on the screen, and these coordinates are used to define the objedt that is recorded into the database and to permit it to be re-created.

• Coordinates for the map to be recorded may also be drawn on the displayed national map using a drawing tool for irregular shapes that may be brought into operation by clicking on a key 90. Defining the locational coordinates for the map to be recorded using the irregular drawing tool also causes the data entry fields 58-64 to be unavailable. The computer stores the object as a polygon whose nodes are defined by the X-Y points that have been input using the mouse or other pointing device, and displays a graphical image of the polygon on the base map for checking that what has been input coincides with the intentions of the user.

• An existing entry may be copied and its attributes then appear in the panel 56. An entry for a duplicate map can then be added to the database without having to enter the entire attribute data set.

Fig 8 provides a classification of the resulting data structure. The data structure enables the individual catalogue layers 95 to relate to both spatially referenced objects 96 (points, lines or areas) and associated digital image files 98, through an image metadata database 97. The individual databases for each catalogue layer 95, can be further subdivided. The identifier field, name field and code field provide fields of an identity field set 102. The scale field and type field provide fields of a layer allocation field set 100. The press field and bar field provide fields of a physical storage location set. The date, "one of ..." and condition fields provide fields of an ancillary searchable field set 105. Not shown in Fig 8 because it is not seen by the user, but important to the operation of the present system is the X-Y coordinate field set which will store X-Y coordinates within the given projection. A single point is defined by a single pair of coordinates, a rectangle for a modern map is defined by a pair of coordinates giving minimum X, minimum Y and maximum X, maximum Y, and a polygon is stored as a series of X-Y points or nodes in the given projection, the nodes being linked by line vectors in a given order (e.g. A>B.C.D.E.A). The number of polygons and their complexity is limited only by the storage capacity of the computer hard drive and is virtually limitless. Optional additional fields for digital image metadata and file addresses 97 provide relational links to digital image files 98. As is apparent from Fig 8, the objects in the metadata database 97 are linked to the objects in the catalogue layers 95 by sharing the same reference code.

The catalogue interrogation mode and its user interface

Clicking on the button 14 of Fig 1 causes the program to enter a database interrogation mode whose user interface is shown in Figs. 9-19. The screens of Figs 9-11 correspond closely to the corresponding screens in data entry mode. Thus the screen 120 provides a selection of continent and screen 122 provides selections of country and format. Figure 11, screen 124 aids the user in his selection of scales by virtue of a graphical display of sample thumbnails 127. Panel 125 provides for selection of scales. Scales can be selected in any number of combinations. An 'ALL' check box enables the user to select all available scales. Fields 126 and 128 provide for input of a search time span criterion based on the information in the date field. Such a criterion could be used to sort, for example, for maps held in the collection for an area around Dorchester and made in the period 1750 - 1850. If no data is entered in these fields, the search engine reports records for all years

Reaching Fig 12 causes a base map of the selected country 130 to be displayed together with a panel 132 showing the search criteria and a results summary e.g. the number of hits. The results, i.e. the individual hits are displayed as points, points or rectangles on the base map as shown, The use of zoom buttons and map pan buttons (44,46&48) enables the user to define the spatial extent of the base map shown on the screen at any one time. As the user zooms in on the base map, figure 13, greater detail is revealed to further aid the accuracy of catalogue interrogation. Spatial definition of the search criteria can be achieved in one of six ways; 'Click on a point' button 168, 'Gazateer' button 140, 'Known Coordinates' button 154, 'Rectangular area marquee' button 170, 'Irregular area marquee' button 171 and 'Radius area marquee' button 172.

• Clicking on a desired location 168 using a mouse causes the selected location to be highlighted as in figure 14 and an overlay 166 to appear giving a cross hair to specify the location chosen and the corresponding coordinates.

• Clicking on a gazetteer search button 140, figure 15, displays a panel 142 that activates a gazetteer search tool. Entry of a character string for a named location in search field 144 and clicking on search button 146 invokes a separate geocoded database which searches for the inputted named location and returns a corresponding point coordinate. The system checks with the user that this does indeed correspond to the correct location by displaying the match in panel 148. Clicking on the "go there" button 150 returns to the map display figure 16, but with a highlighted portion 152 corresponding to the named location selected and with an overlay showing the name of the place selected.

• Clicking on a point specific search button 154, figure 17, for displaying a panel 156 activates a point specific search tool. Direct input into search fields 158, 160 of character strings for the X and Y coordinates specified followed by clicking on the "go-there" button 162 returns to the map but with a highlighted portion 164 corresponding to the selected coordinates and with an overlay showing the coordinates.

• Clicking on an area search buttons 170, 171 & 172 activates an area search tool by which a user can define an area to be searched using a drag-and drop tool. This is particularly useful when the spatial information catalogue layers involve point location data such as slides taken from a defined point. For area objects selection is achieved when more than 25% of the area is selected (included within) the area defined by the tool. The Rectangular search tool, 170, defines areas of a rectangular shape. Once defined the area is shown on the base map, figure 18, along with the top left and bottom right coordinates. The irregular polygon tool, 171, enables the user to 'trace' irregular shapes such as the outlines of islands and so be more specific in defining an area search. The radius tool, 172, searches a circular area centered on a given point (selected by clicking with the mouse on the base map) of a given radius (measured in kilometers) chosen by the user.

The selections made using screens 120-124 provide coarse resolution filtering and the selected spatial definition provides the final filter. The panel 132 then provides a report of the selected search criteria in terms of the layers selected by the layer allocation fields 100, the coordinates selected by the place or area fields 96 and any additional search criteria amongst the ancillary field set 105. Clicking on button 190 causes a tabulated report figure 19 to be displayed, which includes identifier information and location information for the maps or other articles that have been retrieved by the report. The report is generated by finding those objects within the relevant database layers whose X-Y coordinates match the query that has been input. For a point, the computer returns those objects whose stored X and Y coordinates match or cover the X and Y coordinates of the selected point. For a rectangle, the search tool returns the objects that fall at least 25% by area within the selected range of minimum X, minimum Y, maximum X, maximum Y. For a polygon, the computer retrieves those objects that fall within the area of the polygon, the Infotool function of Maplnfo being adaptable to provide the required report. When the user is satisfied with his search criteria, he can cause full details of the relevant holdings of spatial information to be printed out along with metadata on the search criteria, time and date (figure 20). Image viewer facility

The present program can be used to give access both to maps and other spatial information that is originated in digital form as well as digital information that has been created by scanning hard copy images. Maps selected through the interrogation process may be used to provide a link to a separate database 97 containing metadata and addresses that the present program can search to find an associated digital image 98. A geographic desktop mapping program, for example Maplnfo whose facilities are used by the present program can open all major image format types (.jpg, .tiff, .wmf etc) as well as images compressed using compression algorithms such as ECW. Adopting a relational database design has several advantages over an integration of addresses into the main catalogue layers. Chief amongst these is the capacity to update the digital records and bring them on- and off-line without affecting the main indexing functionality of the present program.

Once an image has been selected for viewing by the present program, it is opened into a geographic information system (GIS) environment, with a display figure 21 of a digital image of the selected map which can be controlled by zoom and pan tools and can be printed as a whole or as a part at a selected magnification. The display includes a panel 178 that displays image meta-data. A selector dialog box has a panel 182 with fields for displaying a menu of identifiers for maps or other images that have been found as a result of a database search, in the case of a map the scale of the map and the availability of a digital image. The user can scroll up or down the menu to select an image for display and then click on view button 184. When the user is satisfied with the scale and coverage of his screen image, he can cause the image on the screen to be printed out along with image metadata, time and date (figure 22). Map Return facility

A Map Return facility is provided by the program to aid the user in identifying and locating the correct archive point for a particular hardcopy map or object. The button 17, screen 10, figure 1, opens a data entry window 200, figure 23 into which the user can type the unique code number of an object. The user can then search the entire catalogue by virtue of the search button 202 or return to the opening screen via the exit button 201. The search results are viewed via a second information panel figure 24. This panel reveals to the user the press and bar number where the object is held along with other textual information that may be held by the catalogue (panel 204). In addition, a locator map is provided to the user (205), so as to aid a less familiar user with the layout of the particular archive area highlighting both where the user is currently positioned and the corresponding location of the appropriate press. The user can then go to the indicated location and retrieve the article that he requires.

A computer program as aforesaid may be provided in a variety of forms. It may be recorded onto a data carrier, for example a magnetic or optical disk or a tape. It may also be provided via a network in the form of an electronic signal that can be received by the computer where the program is intended to be installed, e.g. as a down-loadable file transmitted via the Internet.

The ability to provide a computer-based search using the above program brings with it a number of benefits.

Users of a museum or library can carry out their own searches for material held in the library either by using client computers on-site or by remote access using a network it the Internet, and unnecessary use of the time of curators or librarians is avoided.

Provision of an accurate "virtual' search for users with reference to a computer-held catalogue avoids unnecessary handling of originals which in the past has been an inherent feature of manual searches. This is particularly important for collections that hold historical or other irreplaceable maps where the operations of handling and sorting impose wear on the original, and the benefits of minimizing such operations are self-evident.

The catalogue entry can be linked to a digitally scanned image of the original map, which can then be viewed and used to provide copies. The user can be provided with the information stored on the original and with copies on demand, and the original can be moved to a controlled conservation archive where handling is minimized and priority can be given to conservation rather than physical access.

Claims

1. A computer program product loadable into the memory of a computer for storage and retrieval of information concerning spatially related articles, said program product comprising: computer-readable instructions for causing the computer to maintain a relational database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system; computer-readable instructions for causing the computer to enter records into the database; and computer-readable instructions for interrogating the database using X and

Y coordinates within the geographic location system.

2. The product of claim 1, having computer-readable instructions for entry and maintenance of records for articles associated with a place of negligible geographical extent and defined by a single pair of X and Y coordinates.

3. The product of claim 1 or 2, having computer-readable instructions for entry and maintenance of records for articles that are square or rectangular maps made within the geographic location system and whose area is defined by two pairs of X and Y coordinates defining the positions of a pair of opposite corners of the map.

4. The product of claim 1, 2 or 3, having computer-readable instructions for entry and maintenance of records for articles that are maps of irregular shape and whose area is defined by a multiplicity of pairs of X and Y coordinates.

5. The product of any preceding claim having computer-readable instructions for entry and maintenance of records having a fourth field set defining ancillary searchable fields.

6. The product of any preceding claim, having: computer-readable instructions for causing the computer to maintain a plurality of relational databases each comprising a plurality of records for articles in which each record has a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system; and wherein each record has a fourth field set containing at least part of the data for allocating the record to one of the relational databases.

7. The product of claim 6, wherein each record has part of the data for allocating itself to one of the relational databases, and the computer-readable instructions for causing the computer to enter the record include instructions for entry of the remainder of the data for allocating the record to one of the relational databases.

8. The product of any preceding claim, wherein the computer-readable instructions for causing the computer to enter the record include instructions for display of portions of a base map and drawing tools for drawing areas on the base map for indicating coordinates relating to records.

9. The product of claim 8, wherein the drawing tools include a rectangle drawing tool.

10. The product of claim 8 or 9, wherein the drawing tools include tools for drawing an irregular shape.

11. The product of any preceding claim, wherein the computer-readable instructions for interrogating the database include means for displaying a base map and means for entering the query by indicating a point or area of the base map.

12. The product of any preceding claim, further comprising an image viewer for viewing digital images found by interrogating the database.

13. The product of any preceding claim, when installed on a stand-alone computer.

14. The product of any preceding claim when installed on a computer network.

15. A relational database for use in the storage and retrieval of information concerning spatially related articles, said database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system.

16. The database of claim 15, wherein the articles are in a collection, and the second field set defines locations for the articles in the collection.

17. The database of claim 15, wherein the second field set contains data that defines locations for physical articles.

18. The database of claim 15 or 16, wherein the second field set contains data that defines addresses or links to digitally stored articles.

19. The database of any of claims 15-18, wherein at least some of the articles are maps.

20. A record for a relational database concerning spatially related articles, said record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system.

21. A method for creating a database for storage and retrieval of information concerning spatially related articles, said method comprising entering records into the database of any of claims 1-14.

22. The method of claim 21, wherein at least some of the records relate to maps.

23. A method of interrogating the database of any of claims 15-19, which comprises supplying to the database a query that includes at least one pair of X and Y coordinates within the geographic location system.

24. A computer program product loadable into the memory of a computer for storage and retrieval of information concerning spatially related articles, wherein the program includes instructions for display during storage and retrieval of information of a base map in a predetermined projection, and instructions for cataloguing the articles in a database on the basis of one or more stored X-Y coordinates in the projection.

25. A method of retrieving an article on the basis of a spatial relationship, which comprises: providing a relational database which stores and permits and retrieval of information concerning spatially related articles, said database comprising a plurality of records for articles catalogued in the database, each record having a first field set for identity data for the article, a second field set for data defining a storage location for the article and a third field set for coordinates defining a place or area of or associated with the article and that includes at least one pair of fields for X and Y coordinates within a geographic location system; displaying a base map; generating a query by selecting at least one point on the base map and supplying to the database a query that includes at least one pair of X and Y coordinates within the geographic location system corresponding to said at least one point; generating a report of articles and their storage locations on the basis of said at least one pair of X and Y coordinates; and retrieving at least one article on the basis of its storage location.

26. The method of claim 25, wherein the article is a physical article and the storage location is a physical location within a collection.

27. The method of claim 27, wherein the article is a map and the storage location is the press and bar where the map is held.

28. The method of claim 25, wherein the article is stored electronically and the storage location is an address on a computer or network, or a link to a said address.