United States Patent (19)
`Backman et al.
`
`54 HAND-HELD GPS-MAPPING DEVICE
`
`75 Inventors: Douglas J. Backman, Southbourough,
`Mass., Gene V. Roe, Henniker, N.H.,
`Frank D. Defalco, Worcester; William
`R. Michallson, Charlton, both of Mass.
`
`73 ASSignee: American Navigation Systems, Inc.,
`Millbury, Mass.
`
`56)
`
`21 Appl. No.: 08/835,037
`22 Filed:
`Mar 27, 1997
`Related U.S. Application Data
`60 Provisional application No. 60/031,655, Nov. 19, 1996.
`(51) Int. Cl. .................................................. G06F 9/00
`52 U.S. Cl. ............................................. 701/200, 701/208
`58 Field of Search ..................................... 701/200, 207
`701/208: 382/113, 173, 180.232.256.
`276, 305; 353/25, 39
`References Cited
`U.S. PATENT DOCUMENTS
`6/1972 Meilander .
`3.668,403
`5/1985 Schwab et al. .
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`4.550,317 10/1985 Moriyama et al. ..................... 340/995
`4,598.372 7/1986 McRoberts.
`4,633,506 12/1986 Kato.
`4,660,037 4/1987 Nakamura.
`4,661,811
`4/1987 Gray et al..
`4,815,012 3/1989 Feintuch .................................. 364/521
`4,827,418 5/1989 Gerstenfeld.
`4,888,698 12/1989 Driessen et al. ........................ 364443
`4,890.233 12/1989 Ando et al..
`4,896,154
`1/1990 Factor et al..
`4,949,089 8/1990 Ruszkowski, Jr..
`4,949,267 8/1990 Gerstenfeld et al..
`4,975,696 12/1990 Salter, Jr. et al..
`4,979,137 12/1990 Gerstenfeld et al..
`4,994,794 2/1991 Price et al..
`5,025,382
`6/1991 Artz.
`5,129,011
`7/1992 Nishikawa et al..
`5,168,384 12/1992 Genba ....................................... 359/83
`5,281,957
`1/1994 Schoolman.
`
`USOO5902347A
`Patent Number:
`11
`(45) Date of Patent:
`
`5,902,347
`May 11, 1999
`
`5,315,298 5/1994 Morita ..................................... 340/995
`5,381.338
`1/1995 Wysocki et al. ........................ 364/449
`5,412,573 5/1995 Barnea et al..
`5,422,814 6/1995 Sprague et al..
`5,504,684 4/1996 Lau et al..
`5,528.248 6/1996 Steiner et al..
`5,550,743 8/1996 Kyrtsos.
`5,552,989 9/1996 Bertrand.
`5,568,152 10/1996 Janky et al. .
`5,699,115 12/1997 Hiraki et al. ............................ 348/333
`5,699,244 12/1997 Clark, Jr et al. ....................... 364/420
`OTHER PUBLICATIONS
`Polytronix product brochure for GPS Displays. (Jun. 1998).
`InterVision product brochure for System 6 Wearable Com
`puter. (Feb. 10, 1998).
`Microslate product brochure for pen computer. (Jun. 1997).
`Advertisement for Eagle map guide, SkyMall magazine.
`(undated).
`James Associates, brochure “Garmin GPS Receivers
`Handheld", pp. 1-8, (No Date).
`Primary Examiner William A. Cuchlinski, Jr.
`Assistant Examiner Edward Pipala
`57
`ABSTRACT
`A hand-held navigation, mapping and positioning device
`contains a GPS receiver, a database capable of Storing vector
`or bit mapped graphics, a viewing port, an embedded
`processor, a simplified user interface, a data compression
`algorithm, and other Supporting electronics. The viewpoint
`is configured Such that the data presented in the viewport is
`clearly visible in any ambient light condition. The database
`Stores compressed image data which might include topo
`graphical map data, user annotations, building plans, or any
`other image. The System includes an interface to a personal
`computer which may be used to annotate or edit graphic
`information externally to the device for later upload. In
`addition, the device contains a simple menu-driven user
`interface which allows panning and Zooming the image data,
`marking locations of interest, and other Such functions. The
`device may be operated from an internal rechargeable
`battery, or powered externally.
`
`18 Claims, 8 Drawing Sheets
`
`y
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`
`Optical
`Viewport
`
`Color
`Display
`
`Display
`Electronics
`
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`
`12
`- - - - - - - -->
`Non-Volatile
`Embedded :
`Storage
`ProCeSSO
`14
`15
`in-l
`6
`Host
`Keypad
`| Interface
`Interface
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`GPS
`Receiver
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`User
`PC
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`User
`Commands
`
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`U.S. Patent
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`May 11, 1999
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`Sheet 1 of 8
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`5,902,347
`
`---4.----------------------
`
`O
`
`Optical
`Viewport
`
`Color
`Display
`
`Display
`Electronics
`12
`Embeddéd
`PrOCeSSO?
`
`Non-Volatile
`Storage
`
`14
`
`HOSt
`Interface
`
`USer
`PC
`
`S
`
`Keypad
`Interface
`
`User
`Commands
`
`GPS
`ReCeiver
`
`FIG
`
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`U.S. Patent
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`Sheet 2 of 8
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`5,902,347
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`1.
`
`16
`
`FIG2a
`
`
`
`FIG 2c
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`U.S. Patent
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`May 11, 1999
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`Sheet 3 of 8
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`5,902,347
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`FIG 3
`
`
`
`FIG 4
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`U.S. Patent
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`May 11, 1999
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`Sheet 4 of 8
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`5,902,347
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`9,6
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`S OIH
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`+
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`May 11,1999
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`Sheet 5 0f 8
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`5,902,347
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`24
`
`
`PixelLine1 PixelLanN
`
`
`Decompress
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`FIG6
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`23 ImageData
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`
`21
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`
`
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`
`|PR2020-01192
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`U.S. Patent
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`May 11, 1999
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`Sheet 6 of 8
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`5,902,347
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`US. Patent
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`May 11,1999
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`Sheet 7 0f 8
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`5,902,347
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`U.S. Patent
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`May 11, 1999
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`Sheet 8 of 8
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`5,902,347
`
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`

`1
`HAND-HELD GPS-MAPPING DEVICE
`
`This application is a continuation of U.S. Provisional
`application Ser. No. 60/031,655, filed Nov. 19, 1996.
`FIELD OF THE INTENTION
`This invention relates generally to navigation and tracking
`and Specifically to providing real-time positioning on a map
`image.
`
`BACKGROUND OF THE INVENTION
`Most personal navigation Systems exist as hand-held
`devices which report position interns of latitude, longitude,
`and altitude. Primitive mapping functions are usually pro
`vided that display the path that a user has followed or
`provide a simple Steering indication to facilitate taking a
`Straight line path towards a desired coordinate. More Sophis
`ticated Systems may include low resolution map information
`upon which the users coordinates are overlaid.
`There are Several problems with these existing Systems.
`First, the use of LCD-type displays makes these devices
`Virtually unusable in direct Sunlight because of insufficient
`display contrast. Second, because the Storage of detailed
`images requires large amounts of data Storage, map resolu
`tion is limited. Third, because of these Storage limitations
`and because of the difficulty of obtaining accurate map data,
`the Selection of maps for users to exploit is very Small.
`Addressing these issues requires a device which makes
`improvements in two fundamental areas. First, a new display
`System is needed which will allow the user to See presented
`images clearly in all lighting conditions. Second, improve
`ments in data storage must be made to allow the user to store
`a meaningful amount of high accuracy data.
`BRIEF DESCRIPTION OF THE DRAWINGS
`The elements of the device described in the following
`paragraphs which constitute the invention are established in
`the appended claims. However, understanding the nature of
`the invention is aided by fully disclosing the characteristics
`of the device. The following diagrams and illustrations are
`provided to aid in this understanding:
`FIG. 1 is a block diagram representation of the entire
`System.
`FIGS. 2a, 2b and 2c illustrate the mechanical concept,
`showing a likeness of tile anticipated packaging of the
`hand-held portion of the System.
`FIG. 3 illustrates the mechanical concept of the optical
`viewport which shows how the optics are oriented relative to
`the display and electronic cabling.
`FIG. 4 illustrates the arrangement of lenses relative to the
`display and details aspects important to Shielding the display
`from ambient light.
`FIG. 5 illustrates the basic concept behind the organiza
`tion of a TIFF format data file.
`FIG. 6 is a flow diagram of the encoding/decoding proceSS
`for georeferenced data Storage.
`FIG. 7 describes the approach used to attach geographic
`Significance to the Stored data file.
`FIG. 8 is a flow diagram of a tile-based compression
`proceSS embodying the principles of the present invention.
`FIG. 9 portrays an approach to providing geographical
`referencing for each image tile within an image.
`FIG. 10 illustrates the concept of a tile-based image data
`file embodying the principles of the present invention.
`
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`DETAILED DESCRIPTION OF THE
`INVENTION
`A block diagram of the system is provided in FIG. 1. As
`illustrated in the figure, the System 10 contains an optical
`viewport 11 which takes a small (nominally 18 mm
`diagonal) LCD or equivalent display and expands the image
`Such that it appears to the user as a full-size size computer
`display. The image is controlled by an embedded processor
`12 which retrieves georeferenced map data from a non
`Volatile Storage System. The processor uses position infor
`mation received from the GPS receiver 13 and creates an
`image showing the user's position on the color display. The
`host interface 14 is used to load map data into the handheld
`unit and the user interface 15 contains pushbuttons for the
`user to pan and Zoom and which allow Setting up and
`configuring the unit.
`The purpose of this device is to allow a user to Store maps
`and other information in a Small portable device that also
`provides position information using a GPS receiver. When
`using this device, a user would typically obtain raster-format
`digitized maps which would be edited using companion
`Software on a personal computer. Edits might include the
`addition of points of interest, waypoints, trails, or other
`pertinent data. This information would then be uploaded to
`the device, which would store it in non-volatile memory.
`Non-volatile Storage may also reside on removable memory
`cards which the user inserts into the handheld unit.
`In operation, the device then becomes Self-contained,
`housing a GPS receiver, internal rechargable batteries, map
`data, and a user display. Using a menu driven interface, the
`user can see where they are on the map and perform other
`functions Such as calculating the distance to a particular
`point, or panning and Zooming the image to investigate map
`details. To Support users without access to a personal
`computer, the design shall also allow the user to purchase
`memory, cards that are pre-programmed with map data
`covering Specific geographical regions to which the user can
`add waypoints, trails and other information using the
`devices user interface.
`In this device there are two areas which required the
`development of new technology: the optical viewport and
`the georeferenced data Storage/access.
`FIG. 2 illustrates the anticipated mechanical configuration
`of the device. The device will be housed in a high-impact
`plastic case 16 that is Sufficiently conductive internally to
`shield the internal electronics. On the left side (as viewed
`from the top) is an optical viewing port 11 that allows the
`user to See an internal display. In general, the Viewport
`housing may be movable to allow the user additional flex
`ibility when operating the device.
`Along the top of the device are user interface buttons. A
`hexagonal pad dominates the user interface and provides the
`user the ability to Scroll the display right, left, up, down, or
`along a diagonal. Additional buttons are provided to allow
`the user to Zoom in or out, turn the unit on or off, and to
`provide additional functions. The front of the unit will hold
`jacks for communications with an external PC, memory
`cards, and power for using an external battery and recharg
`ing the internal batteries. The antenna for the GPS receiver
`will be contained internally. Sand, and other environmental
`hazards.
`A mechanical Overview of the optical viewport is illus
`trated in FIG. 3. At the front end of the device, a rubber
`bellows Similar in nature to a camera light Shield reduces the
`amount of external light which enters the Viewport. A System
`of plastic, polycarbonate, or glass lenses gives the user the
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`illusion that they are viewing a much larger Screen than
`physically exists in the device. The goal is to have the image
`appear to be approximately 22x30 centimeters as viewed
`from a distance of about 40-60 centimeters. The display
`interfaces to the electronics using a flexible cable which
`passes from the viewpoint housing into the electronics area
`of the main housing.
`To prevent the entry of contaminants, the viewpoint
`housing halves may include a compression gasket. Similarly,
`the mechanical Supports for the optical components may be
`designed to provide a gas proof Seal. Nothing in the design
`shall prohibit using techniqueS Such as filling the optical area
`with an inert gas to inhibit the formation of condensation if
`the device is Subjected to temperature and humidity
`eXtremeS.
`The details of the actual imaging System are provided in
`FIG. 4. Novel characteristics of the viewport include a lack
`of movable components and Sufficient Shielding of ambient
`light that the display becomes uSable in direct Sunlight.
`Conversely, provision for backlighting the display allows
`use of the device in low ambient light conditions. If a focus
`control proves necessary, it would be integrated between the
`eyepiece bellows and the first lens of the imaging System.
`Data Storage and retrieval is a major problem when
`handling geographic data. A typical USGS quad sheet may
`require as much as 40-60 Mbytes of Storage in uncom
`pressed format. With compression, the data Storage require
`ment drops to approximately 10-15 Mbytes.
`In most graphical applications, a 10-15 Mbyte com
`pressed image is decompressed into Virtual memory to its
`original Size at which point it can be accessed as if it was a
`Single large array. Since the total memory available in the
`handheld device will generally be far less than the uncom
`pressed image requires, a more novel data compression,
`retrieval, and Storage Scheme is required.
`It Is essential that the device be able to decompress tif (or
`equivalent) images and do pan/Zoom in real-time without
`having to load the entire (decompressed) image in memory.
`The problem with TIFF, GEOTIFF, and other standard
`image Storage formats is twofold. First, these file formats
`generally allow Storing information randomly in memory.
`Second, the data in the files is compressed into variable
`length records using a technique Such as Bit Packing, LZW
`or Huffman coding. This results in a file that is encoded in
`45
`a manner that makes it difficult to directly access an arbitrary
`portion of the compressed image (as would be common
`when doing pan and Zoom).
`As an example, FIG. 5 illustrates the manner in which a
`TIFF file stores image data. Each TIFF file begins with a
`predefined header which describes certain essential charac
`teristics of the file such as the byte order, the number of
`images in the file, and So on. At the end of the header there
`is a pointer to the first of possibly many directory entries,
`each of which contains information describing where the
`data for the component images is Stored in the file. These
`directories contain pointers to the file locations where lines
`of image data are Stored. Since each line of image data is
`compressed, each record may be of different length.
`The decompression process works in a manner Similar to
`that shown in FIG. 6. The decompression algorithm uses the
`TIFF header information to determine how many data
`pointers exist in the file, how long each image data line
`should be, and the Start address of the data pointers. Next,
`each line is decompressed in Sequence to construct the
`uncompressed image. Only when the image is fully decom
`pressed is the Spatial relationship between pixels fully
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`known since the compression algorithm terminates only
`when it has decompressed a full line of pixels.
`As illustrated in FIG. 7, once the image is fully
`decompressed, precise Spatial relationships can be deter
`mined. This is accomplished by georeferencing the image
`data by correlating pixel locations with land features. By
`knowing the geographic location of one or more reference
`pixels, die orientation of the pixel image, and distance
`represented by adjacent pixels (dx and dy) good conrespon
`dence between the image and the mapped features is
`obtained.
`The proposed solution to this problem is outlined in FIG.
`8. AS shown in the figure, there are two main Steps required
`to process the original TIFF (or other) format image data.
`The first Step involves recovering the original Scanned image
`by decoding it from its original Storage format into a
`complete, uncompressed pixel image. The Second Step
`involves postprocessing the image by dividing it into more
`useful Square arrays, or tiles, of georeferenced pixel data. An
`output file is created which contains header information
`describing Size and geographical location of each tile, point
`ers to the tile data, and compressed tile data.
`AS Shown in FIG. 8, the major Steps required to post
`process the data begin with georeferencing the original
`image followed by tiling. This georeferencing is done by
`appending geographical coordinates (latitude, longitude, and
`altitude) to one or more pixels in the uncompressed image
`and by providing a Suitable mathematical expression to
`relate pixel Spacing to geographical spacing. This math
`ematical expression may be as Simple as a Scaling factor
`Such as 1 pixel=50 feet, or it may be a more complicated
`expression which accounts for Spherical corrections.
`A typical 1:25,000 Scale topographic map spans an area of
`approximately 15x20 kilometers. Since a land user is typi
`cally concerned with only a Small portion of this data at any
`given time, the full image is divided into tiles, each of which
`contains the data for a significantly Smaller region (for
`example 1 Square kilometer). The size of the tiles is gov
`erned by a tradeoff between the number of tiles which must
`be stored uncompressed in memory and the Speed of decom
`pression. In general, it is expected that a land user will
`require at least 4 active tiles in memory to allow SeamleSS
`paining in the event that the user is located at the interSection
`of four tiles.
`Providing geographical referencing for each tile is
`accomplished, as illustrated in FIG. 9, by computing the
`geographic location of each tile. Knowing this information,
`along with the orientation of the tile relative to the full
`image geographical reference point and the Size of the tile,
`allows directly determining which tile contains any possible
`location on the map.
`To facilitate efficient use of the tiled data, a file structure
`such as the one illustrated in FIG. 10 is proposed. A header
`field contains information about the file Structure Such as the
`number of tiles, tile size, number of pixels, aspect ratio, and
`the required geographic interpolation parameters to calcu
`late position. Following the header, is a variable length field
`consisting of fixed length records which include a pointer to
`the Stall of the image data in each tile and the geographical
`reference for the tile. The remaining fields are variable
`length fields which contain compressed image data for each
`tile.
`Given this format, both the location of the tile data in the
`file and the geographic location of the tile reference are both
`known. Because this is true, variable length data fields no
`longer pose a problem, Since each tile covers a minimum
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`acceptable geographic region. Thus, given a user location,
`the tiles needed by the user can be directly identified. Since
`the Starting location of the data is known both geographi
`cally and in terms of data Storage only the desired tile need
`be decompressed. This format also facilitates caching
`uncompressed tiles based on user movement to facilitate
`Smooth pan and Zoom without requiring that the entire
`image be decompressed in memory.
`What is claimed is:
`1. A device for personal, portable mapping and
`navigation, by a user, and adapted to display a map image to
`the user and to display to the user, the user's location, on the
`map image, comprising:
`a) a case;
`b) a digital computer mounted in the case;
`c) a location receiver unit associated with the case and
`adapted to provide user location information to the
`computer,
`d) an image storage unit adapted to Store image data and
`to provide the image data to the computer;
`e) a display unit adapted to receive data from the com
`puter and display the data as an image to the user, the
`display unit having an optical viewport assembly ,
`including a light excluding barrel, a Solid-States Video
`display chip, at one end of the barrel and adapted to
`form an image, a viewing aperture at the other at the
`other end of the barrel, and a lens System mounted in
`the barrel and adapted to present an enlarged version of
`the image to the viewing aperture, and
`f) a computer program adapted to control the computer,
`and to cause the computer to present the user location
`information and the image data to the display unit So
`that the display unit displays, to the user, a map image
`and the user location, on the map image.
`2. A device, as recited in claim 1, wherein Said image data
`includes a plurality of tile data which tiles, taken together,
`represent a map image, Said image data including;
`i) header data describing the size and geographical loca
`tion of each tile,
`ii) pointers to the location, in the Storage unit, of the data
`for each tile,
`iii) compressed tile data for each tile.
`3. A device as recited in claim 2, wherein Said program
`includes;
`i) an associating routine for associating the user location
`with one of the tiles,
`ii) a decompressing routine for decompressing the tile
`data for the Said one of Said tiles into a tile image for
`the Said one of Said tiles, and
`iii) a locating routine for locating the user's location on
`Said tile image.
`4. A device as recited in claim 1, wherein the location
`receiver is a G.P.S. receiver.
`5. A device for personal, portable mapping and
`navigation, by a user, and adapted to display a map image to
`the user and to display, to the user, the user's actual location,
`on the map image, comprising:
`a) a case
`b) a digital computer mounted in the case,
`c) a location receiver unit associated with the case and
`adapted to provide user location information to the
`computer,
`d) an image storage unit adapted to Store image data and
`to provide the image data to the computer, Said image
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`data including a plurality of tile data which tiles, taken
`together, represent a map image, Said image data
`including,
`i) header data describing the size and geographical
`location of each tile,
`ii) pointers to the location, in the Storage unit, of the
`data for each tile,
`iii) compressed tile data for each tile,
`e) a display unit adapted to receive data from the com
`puter and display the data as an image to the user,
`f) a computer program adapted to control the computer,
`and to cause the computer to present the user location
`information and the image data to the display unit So
`that the display unit displays, to the user, a map image
`and the user's actual location, on the map image, Said
`program including,
`i) an associating routine for associating the user loca
`tion with one of the tiles,
`ii) a decompressing routine for decompressing the tile
`data for the Said one of Said tiles into a tile image for
`the Said one of Said tiles, and
`iii) a locating routine for locating the user's location on
`Said tile image.
`6. A device as recited in claim 5, wherein the program
`includes a peripheral routine which identifies and decom
`presses a peripheral tile which is adjacent to the Said one of
`Said tile, So that the decompressed image of Said peripheral
`tile is available to the computer for visual effects.
`7. A device as recited in claim 6, wherein the program
`includes a projection routine which projects the movement
`trend of the user's location and identifies and decompresses
`the Successor tile which is adjacent the Said one of Said tile
`and in the path of movement of the user's location, So that
`the decompressed image of Said Successor tile is available to
`the computer as the user's location changes from the Said
`one of Said tiles to the Said Successor tile.
`8. A device as recited in claim 5, wherein the location
`receiver is a G.P.S. receiver.
`9. A device as recited in claim 5, wherein the header
`contains information about the file Structure including the
`number of tiles, tile size, number of pixels, aspect ratio, and
`the required geographic interpolation parameters to calcu
`late position.
`10. A device as recited in claim 5, wherein the pointer
`recites to the location, in the Storage unit, of the Start of the
`image of a tile and the geographic reference to the tile.
`11. A portable device for displaying map image data to a
`user, comprising
`a CaSC,
`a computer mounted in the case;
`a location receiver unit mounted in the case to provide
`location information to the computer,
`an image Storage unit adapted to Store map image data and
`to provide the map image data to the computer;
`a display unit adapted to receive data from the computer
`and display the data as an image to the user, the display
`unit including a light excluding barrel, a Solid-state
`Video display at one end of the barrel and adapted to
`display an image, a viewing aperture at the other end of
`the barrel, and a lens System mounted in the barrel and
`adapted to present an enlarged version of the image to
`the Viewing apertures, and
`a computer program adapted to control the computer and
`to cause the computer to associate the map image data
`to the location information and to present the user,
`through the display unit, Selected portions of the map
`image data.
`
`IPR2020-01192
`Apple EX1013 Page 12
`
`

`

`5,902,347
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`7
`12. A portable device according to claim 11, wherein Said
`image Storage unit comprises a computer memory having
`Storage for a digital raster map having information repre
`Sentative of pixel data for forming an image, whereby the
`display unit shows magnified Stored pixel data.
`13. A portable device according to claim 12 wherein Said
`computer memory comprises a pc-card.
`14. A portable device according to claim 12, wherein Said
`digital raster map includes information representative of
`topographical data.
`15. A portable device according to claim 11, wherein Said
`computer program includes an image processor capable of
`processing an image file to divide image data Stored in Said
`
`8
`image file into tiles representative of Subsets of the data in
`Said image file.
`16. A portable device according to claim 11, further
`including a cache memory for Storing portions of Said image
`data.
`17. A portable device according to claim 11, further
`including a backlit display.
`18. A portable device according to claim 11, further
`including a focus control for allowing the user to focus the
`image data provided by the display unit.
`
`k
`
`k
`
`k
`
`k
`
`k
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`IPR2020-01192
`Apple EX1013 Page 13
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