WO2009080072A1

WO2009080072A1 - Navigation device and method of operation to process image files

Info

Publication number: WO2009080072A1
Application number: PCT/EP2007/011254
Authority: WO
Inventors: Michiel Salters
Original assignee: TomTom International BV
Current assignee: TomTom International BV
Priority date: 2007-12-20
Filing date: 2007-12-20
Publication date: 2009-07-02
Anticipated expiration: 2010-06-20

Abstract

Apparatus (typically a navigation apparatus) comprises a GPS signal receiver (250), a processor (210), memory (230), and a communication port (270). The apparatus further comprises a location data logging module (390), a file inspector module (392) and a location information generating module (395). The location data logging module (390) is configured to cause the processor to record in the memory a log of location data, date and time, the location data being derived from the GPS signal receiver, and the log representing variation of the location data at different instants in time. The file inspector module (392) is configured to cause the processor to inspect an image file accessible to the apparatus via the communication port. The location information generation module (395) is configured to cause the processor to generate, using the log, location information for the image file.

Description

NAVIGATION DEVICE & METHOD OF OPERATION TO PROCESS IMAGE FILES

Field of the Invention

This invention relates to Positioning System (PS)-equipped devices and methods of operation for processing images. Illustrative embodiments of the invention relate to portable navigation devices (so-called PNDs), in particular PNDs that include Global Positioning System (GPS) signal reception and processing functionality. Other embodiments relate, more generally, to any type of processing device that is configured to execute navigation software so as to provide route planning functionality.

Background to the Invention

Portable digital electronic devices including both (i) camera functionality for capturing still and/or moving images, and (ii) GPS signal reception and processing functionality are known. Such devices include, for example, devices that are principally cameras with GPS functionality, as well as certain portable communicators and/or processing devices (such as certain portable telephones, and certain PDAs (Portable Digital Assistants)) that include both PS functionality and camera functionality. GPS functionality is often married with navigation functionality to provide a PND (portable navigation device).

Such devices including both camera and GPS functionality enable PS data to be recorded at the same time as capture of the still and/or moving image, thereby providing PS metadata for the recorded image. GPS metadata may be useful for indexing, searching and associating images with real geographical locations. The GPS metadata can provide a uniform indexing scheme that may be more reliable than individual titles and place names chosen by individual users. For example, different users may choose very different titles and place names for the same location at which an image is captured.

However, GPS functionality remains a relatively expensive technology due to the receiver and processing requirements. There are many cameras that do not have GPS functionality for recording GPS data when capturing a recorded image. While it may be possible for a user manually to append GPS metadata at a later time, this is highly burdensome and very prone to error. For example, the user might not be aware of the important difference between decimal fractions and minutes, or the user may only have a street address and no GPS coordinates.

It is an aim of the present invention to address these problems. Summary of the Invention

In pursuit of this aim, a presently preferred embodiment of the present invention provides apparatus comprising a positioning system signal receiver, a processor, memory, and a communication port. The apparatus further comprises a location data logging module, a file inspector module and a location information generating module. The location data logging module is configured to cause the processor to record in the memory a log of location data, date and time, the location data being derived from the positioning system signal receiver, and the log representing variation of the location data at different instants in time. The file inspector module is configured to cause the processor to inspect an image file accessible to the apparatus via the communication port. The location information generation module is configured to cause the processor to generate, using the log, location information for the image file.

Features and advantages of the invention include one or more of: (i) the ability to generate location information for image files created by non-PS-equipped camera devices; (ii) the ability to append such location information automatically to image files lacking such information; and (iii) avoidance of the burden and risk of error of a user having manually to calculate and append such location information.

The preferred embodiment illustrates a PND implementing such functionality. The image files may be stored, for example, on a memory card connectable to the PND. The image files may be still images and/or moving images.

Brief Description of the Drawings

Various aspects of the teachings of the present invention, and arrangements embodying those teachings, will hereafter be described by way of illustrative example with reference to the accompanying drawings, in which:

Fig. 1 is a schematic illustration of a Global Positioning System (GPS); Fig. 2 is a schematic illustration of electronic components arranged to provide a navigation device;

Fig. 3 is a schematic illustration of the manner in which a navigation device may receive information over a wireless communication channel;

Figs. 4A and 4B are illustrative perspective views of an implementation of an embodiment of the navigation device;

Fig. 5 is a schematic block diagram of resources implementing functionality in the navigation device; Fig. 6 is a schematic block diagram illustrating a log of recorded location data, date and time information; Fig. 7 is a schematic block diagram illustrating connection of the navigation device to a camera, or to a memory card of the camera;

Fig. 8 is a schematic block diagram illustrating a process for generating location information for image files; and Fig. 9 is a schematic diagram illustrating interpolation to generate file location information for an image file.

Detailed Description of Preferred Embodiments

Preferred embodiments of the present invention will now be described with particular reference to a PND. It should be remembered, however, that the teachings of the present invention are not limited to PNDs but are instead universally applicable to navigation devices of all types. In particular it should be noted that by navigation device we mean any type of route planning device, irrespective of whether that device is embodied as a PND, a navigation device built into a vehicle, or indeed a computing resource (such as a desktop or portable personal computer (PC), mobile telephone or portable digital assistant (PDA)) executing route planning and navigation software.

As will be explained below, the preferred embodiment includes a function for generating location data that may be appended to a digital image file at some time after the digital image file has been captured. The term location data means any kind of information defining a location associated with the image. The location data may, for example, be GPS data or any positioning system or map coordinate data. The preferred embodiment enables location data to be appended for images captured by non-PS- equipped cameras.

Fig. 1 illustrates an example view of Global Positioning System (GPS), usable by navigation devices. GPS is described as an example PS, but the embodiment may use any other satellite or terrestrial signal source to derive location data. Such systems are known and are used for a variety of purposes. In general, GPS is a satellite-radio based navigation system capable of determining continuous position, velocity, time, and in some instances direction information for an unlimited number of users. Formerly known as NAVSTAR, the GPS incorporates a plurality of satellites which orbit the earth in extremely precise orbits. Based on these precise orbits, GPS satellites can relay their location to any number of receiving units. As used herein the term PS does not refer to any specific system, but is a generic term for systems that identifying position from satellite transmitted signals, or other triangulation sources. The GPS system is implemented when a device, specially equipped to receive

GPS data, begins scanning radio frequencies for GPS satellite signals. Upon receiving a radio signal from a GPS satellite, the device determines the precise location of that satellite via one of a plurality of different conventional methods. The device will continue scanning, in most instances, for signals until it has acquired at least three different satellite signals (noting that position is not normally, but can be determined, with only two signals using other triangulation techniques). Implementing geometric triangulation, the receiver utilizes the three known positions to determine its own two-dimensional position relative to the satellites. This can be done in a known manner. Additionally, acquiring a fourth satellite signal will allow the receiving device to calculate its three dimensional position by the same geometrical calculation in a known manner. The position and velocity data can be updated in real time on a continuous basis by an unlimited number of users.

As shown in Figure 1 , the GPS system is denoted generally by reference numeral 100. A plurality of satellites 120 are in orbit about the earth 124. The orbit of each satellite 120 is not necessarily synchronous with the orbits of other satellites 120 and, in fact, is likely asynchronous. A GPS receiver 140 is shown receiving spread spectrum GPS satellite signals 160 from the various satellites 120.

The spread spectrum signals 160, continuously transmitted from each satellite 120, utilize a highly accurate frequency standard accomplished with an extremely accurate atomic clock. Each satellite 120, as part of its data signal transmission 160, transmits a data stream indicative of that particular satellite 120. It is appreciated by those skilled in the relevant art that the GPS receiver device 140 generally acquires spread spectrum GPS satellite signals 160 from at least three satellites 120 for the GPS receiver device 140 to calculate its two-dimensional position by triangulation. Acquisition of an additional signal, resulting in signals 160 from a total of four satellites 120, permits the GPS receiver device 140 to calculate its three-dimensional position in a known manner.

Figure 2 is an illustrative representation of electronic components of a navigation device 200, in block component format. It should be noted that the block diagram of the navigation device 200 is not inclusive of all components of the navigation device, but is only representative of many example components.

The navigation device 200 is located within a housing (not shown). The housing includes a processor 210 connected to an input device 220 and a display screen 240. The input device 220 can include a keyboard device, voice input device, touch panel and/or any other known input device utilised to input information; and the display screen 240 can include any type of display screen such as an LCD display, for example. In a particularly preferred arrangement the input device 220 and display screen 240 are integrated into an integrated input and display device, including a touchpad or touchscreen input so that a user need only touch a portion of the display screen 240 to select one of a plurality of display choices or to activate one of a plurality of virtual buttons. The navigation device may include an output device 260, for example an audible output device (e.g. a loudspeaker). As output device 260 can produce audible information for a user of the navigation device 200, it is should equally be understood that input device 240 can include a microphone and software for receiving input voice commands as well. In the navigation device 200, processor 210 is operatively connected to and set to receive input information from input device 220 via a connection 225, and operatively connected to at least one of display screen 240 and output device 260, via output connections 245, to output information thereto. Further, the processor 210 is operatively connected to memory 230 via connection 235 and is further adapted to receive/send information from/to input/output (I/O) ports 270 via connection 275, wherein the I/O port 270 is connectible to an I/O device 280 external to the navigation device 200. The external I/O device 280 may include, but is not limited to an external listening device such as an earpiece for example. The connection to I/O device 280 can further be a wired or wireless connection to any other external device such as a car stereo unit for hands-free operation and/or for voice activated operation for example, for connection to an ear piece or head phones, and/or for connection to a mobile phone for example, wherein the mobile phone connection may be used to establish a data connection between the navigation device 200 and the internet or any other network for example, and/or to establish a connection to a server via the internet or some other network for example. The external device 280 may also include a digital camera or a digital storage device, the connection enabling the navigation device 200 to access files (especially image files) stored on the camera or storage device. For example, the image files may be displayed on the screen 240. The image files may include still image files (for example, stored in conventional JPEG or TIFF format) and/or moving image files (for example, stored in compressed form such as any MPEG coding). In one form, the I/O ports 270 include a memory card port 270a for establishing a connection to a removable memory card 280b. The memory card may, for example, be an SD memory card or any type of memory card that finds use in digital cameras.

Fig. 2 further illustrates an operative connection between the processor 210 and an antenna/receiver 250 via connection 255, wherein the antenna/receiver 250 can be a GPS antenna/receiver for example. It will be understood that the antenna and receiver designated by reference numeral 250 are combined schematically for illustration, but that the antenna and receiver may be separately located components, and that the antenna may be a GPS patch antenna or helical antenna for example.

Further, it will be understood by one of ordinary skill in the art that the electronic components shown in Fig. 2 are powered by power sources (not shown) in a conventional manner. As will be understood by one of ordinary skill in the art, different configurations of the components shown in Fig. 2 are considered to be within the scope of the present application. For example, the components shown in Fig. 2 may be in communication with one another via wired and/or wireless connections and the like. Thus, the scope of the navigation device 200 of the present application includes a portable or handheld navigation device 200.

In addition, the portable or handheld navigation device 200 of Fig. 2 can be connected or "docked" in a known manner to a vehicle such as a bicycle, a motorbike, a car or a boat for example. Such a navigation device 200 is then removable from the docked location for portable or handheld navigation use.

Referring now to Fig. 3, the navigation device 200 may establish a "mobile" or telecommunications network connection with a server 302 via a mobile device (not shown) (such as a mobile phone, PDA, and/or any device with mobile phone technology) establishing a digital connection (such as a digital connection via known Bluetooth technology for example). Thereafter, through its network service provider, the mobile device can establish a network connection (through the internet for example) with a server 302. As such, a "mobile" network connection is established between the navigation device 200 (which can be, and often times is mobile as it travels alone and/or in a vehicle) and the server 302 to provide a "real-time" or at least very "up to date" gateway for information.

The establishing of the network connection between the mobile device (via a service provider) and another device such as the server 302, using an internet (such as the World Wide Web) for example, can be done in a known manner. This can include use of TCP/IP layered protocol for example. The mobile device can utilize any number of communication standards such as CDMA, GSM, WAN, etc.

As such, an internet connection may be utilised which is achieved via data connection, via a mobile phone or mobile phone technology within the navigation device 200 for example. For this connection, an internet connection between the server 302 and the navigation device 200 is established. This can be done, for example, through a mobile phone or other mobile device and a GPRS (General Packet Radio Service)- connection (GPRS connection is a high-speed data connection for mobile devices provided by telecom operators; GPRS is a method to connect to the internet).

The navigation device 200 can further complete a data connection with the mobile device, and eventually with the internet and server 302, via existing Bluetooth technology for example, in a known manner, wherein the data protocol can utilize any number of standards, such as the GSRM, the Data Protocol Standard for the GSM standard, for example.

The navigation device 200 may include its own mobile phone technology within the navigation device 200 itself (including an antenna for example, or optionally using the internal antenna of the navigation device 200). The mobile phone technology within the navigation device 200 can include internal components as specified above, and/or can include an insertable card (e.g. Subscriber Identity Module or SIM card), complete with necessary mobile phone technology and/or an antenna for example. As such, mobile phone technology within the navigation device 200 can similarly establish a network connection between the navigation device 200 and the server 302, via the internet for example, in a manner similar to that of any mobile device.

For GRPS phone settings, a Bluetooth enabled navigation device may be used to correctly work with the ever changing spectrum of mobile phone models, manufacturers, etc., model/manufacturer specific settings may be stored on the navigation device 200 for example. The data stored for this information can be updated. In Fig. 3 the navigation device 200 is depicted as being in communication with the server 302 via a generic communications channel 318 that can be implemented by any of a number of different arrangements. The server 302 and a navigation device 200 can communicate when a connection via communications channel 318 is established between the server 302 and the navigation device 200 (noting that such a connection can be a data connection via mobile device, a direct connection via personal computer via the internet, etc.).

The server 302 includes, in addition to other components which may not be illustrated, a processor 304 operatively connected to a memory 306 and further operatively connected, via a wired or wireless connection 314, to a mass data storage device 312. The processor 304 is further operatively connected to transmitter 308 and receiver 310, to transmit and send information to and from navigation device 200 via communications channel 318. The signals sent and received may include data, communication, and/or other propagated signals. The transmitter 308 and receiver 310 may be selected or designed according to the communications requirement and communication technology used in the communication design for the navigation system 200. Further, it should be noted that the functions of transmitter 308 and receiver 310 may be combined into a signal transceiver.

Server 302 is further connected to (or includes) a mass storage device 312, noting that the mass storage device 312 may be coupled to the server 302 via communication link 314. The mass storage device 312 contains a store of navigation data and map information, and can again be a separate device from the server 302 or can be incorporated into the server 302.

The navigation device 200 is adapted to communicate with the server 302 through communications channel 318, and includes processor, memory, etc. as previously described with regard to Fig. 2, as well as transmitter 320 and receiver 322 to send and receive signals and/or data through the communications channel 318, noting that these devices can further be used to communicate with devices other than server 302. Further, the transmitter 320 and receiver 322 are selected or designed according to communication requirements and communication technology used in the communication design for the navigation device 200 and the functions of the transmitter 320 and receiver 322 may be combined into a single transceiver.

Software stored in server memory 306 provides instructions for the processor 304 and allows the server 302 to provide services to the navigation device 200. One service provided by the server 302 involves processing requests from the navigation device 200 and transmitting navigation data from the mass data storage 312 to the navigation device 200. Another service provided by the server 302 includes processing the navigation data using various algorithms for a desired application and sending the results of these calculations to the navigation device 200.

The communication channel 318 generically represents the propagating medium or path that connects the navigation device 200 and the server 302. Both the server 302 and navigation device 200 include a transmitter for transmitting data through the communication channel and a receiver for receiving data that has been transmitted through the communication channel.

The communication channel 318 is not limited to a particular communication technology. Additionally, the communication channel 318 is not limited to a single communication technology; that is, the channel 318 may include several communication links that use a variety of technology. For example, the communication channel 318 can be adapted to provide a path for electrical, optical, and/or electromagnetic communications, etc. As such, the communication channel 318 includes, but is not limited to, one or a combination of the following: electric circuits, electrical conductors such as wires and coaxial cables, fiber optic cables, converters, radio-frequency (rf) waves, the atmosphere, empty space, etc. Furthermore, the communication channel 318 can include intermediate devices such as routers, repeaters, buffers, transmitters, and receivers, for example.

In one illustrative arrangement, the communication channel 318 includes telephone and computer networks. Furthermore, the communication channel 318 may be capable of accommodating wireless communication such as radio frequency, microwave frequency, infrared communication, etc. Additionally, the communication channel 318 can accommodate satellite communication.

The communication signals transmitted through the communication channel 318 include, but are not limited to, signals as may be required or desired for given communication technology. For example, the signals may be adapted to be used in cellular communication technology such as Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Code Division Multiple Access (CDMA), Global System for Mobile Communications (GSM), etc. Both digital and analogue signals can be transmitted through the communication channel 318. These signals may be modulated, encrypted and/or compressed signals as may be desirable for the communication technology.

The server 302 includes a remote server accessible by the navigation device 200 via a wireless channel. The server 302 may include a network server located on a local area network (LAN), wide area network (WAN), virtual private network (VPN), etc. The server 302 may include a personal computer such as a desktop or laptop computer, and the communication channel 318 may be a cable connected between the personal computer and the navigation device 200. Alternatively, a personal computer may be connected between the navigation device 200 and the server 302 to establish an internet connection between the server 302 and the navigation device 200. Alternatively, a mobile telephone or other handheld device may establish a wireless connection to the internet, for connecting the navigation device 200 to the server 302 via the internet.

The navigation device 200 may be provided with information from the server 302 via information downloads which may be periodically updated automatically or upon a user connecting navigation device 200 to the server 302 and/or may be more dynamic upon a more constant or frequent connection being made between the server 302 and navigation device 200 via a wireless mobile connection device and TCP/IP connection for example. For many dynamic calculations, the processor 304 in the server 302 may be used to handle the bulk of the processing needs, however, processor 210 of navigation device 200 can also handle much processing and calculation, oftentimes independent of a connection to a server 302. As indicated above in Fig. 2, a navigation device 200 includes a processor 210, an input device 220, and a display screen 240. The input device 220 and display screen 240 are integrated into an integrated input and display device to enable both input of information (via direct input, menu selection, etc.) and display of information through a touch panel screen, for example. Such a screen may be a touch input LCD screen, for example, as is well known to those of ordinary skill in the art. Further, the navigation device 200 can also include any additional input device 220 and/or any additional output device 241, such as audio input/output devices for example.

Figs 4A and 4B are perspective views of a navigation device 200. As shown in Fig. 4A, the navigation device 200 may be a unit that includes an integrated input and display device 290 (a touch panel screen for example) and the other components of fig. 2 (including but not limited to internal GPS receiver 250, microprocessor 210, a power supply, memory systems 230, etc.). The memory card port 270a may conveniently be located on the front panel of the device 200, or at any other desired internal or external position.

The navigation device 200 may sit on an arm 292, which itself may be secured to a vehicle dashboard/window/etc, using a suction cup 294. This arm 292 is one example of a docking station to which the navigation device 200 can be docked.

As shown in Fig. 4B, the navigation device 200 can be docked or otherwise connected to an arm 292 of the docking station by snap connecting the navigation device 292 to the arm 292 for example. The navigation device 200 may then be rotatable on the arm 292, as shown by the arrow of Fig. 4B. To release the connection between the navigation device 200 and the docking station, a button on the navigation device 200 may be pressed, for example. Other equally suitable arrangements for coupling and decoupling the navigation device to a docking station are well known to persons of ordinary skill in the art.

Referring to Fig. 5, the processor 210 and memory 230 cooperate to establish a BIOS (Basic Input/Output System) 350 that functions as an interface between the functional hardware components 360 of the navigation device 200 and the software executed by the device. The processor then loads from memory 210 an operating system 370 which provides an environment in which application software 380 (implementing some or all of the a boved escribed functionality) can run. In accordance with the preferred embodiment of the present invention, part of this functionality comprises a log generation module 390, a file inspector module 392, and a location information generation module 395, the functions of which will now be described in detail. Referring to Fig. 6, log generation module 390 is configured to maintain a log 400 of the real-time movement and position of the navigation device 200, determined according to the GPS parameters. The log may represent date-time-location information. Such a log 400 may be referred to as a triplog. The log may comprise a series of pairs 405 of date information 405a and time information 405b, and location data 410 associated with the date-time pair 405. The date and time information may be represented in separate fields of the date-time pair 405, or the date and time information may be integrated together as a combined date-time stamp. The location data 410 may be GPS data in the form of GPS co-ordinates, or any other co-ordinate data for identifying a position on a map. The location data 410 may be two-dimensional data (e.g. depicting a position on a horizontal map), or three-dimensional data (e.g. additionally depicting altitude). The log 400 may also indicate when the navigation device is stationary or moving. For example, the data-time pair 405 may represent a time interval range or duration over which the location data is valid, when the navigation device is stationary or does not move significantly.

The log generation module 390 may generate the log 400 using any conventional technique. For the avoidance of doubt, possible examples include, but are not limited to: time sampling the date-time-location information, and recording a log entry at each predetermined time interval; location sampling the date-time-location information, and recording a log entry at each predetermined interval of geographic movement; recording a log entry at each significant waypoint along a navigation route; and recording a log entry when the PS determined location of the device 200 is near a point of interest previously indicated in map data (for example, the point of interest may be manually inputted to the device 200, or it may be incorporated in pre-loaded map data); or a combination of any two or more of the above. The log 400 may be recorded in a compressed format, such that the information is coded to reduce redundancy and data size. For example, when the navigation device is stationary, significant data efficiency may be obtained by indicating the length of time that the device is stationary, so that any intermediate entries in the log 400 may be deleted as redundant. The recording of information by the log generation module 390 may be automatic and hidden from user intervention, or it may be a process that a user can at least partly control manually, for example, according to user adjustable preferences, and/or by permitting the user to start and stop recording of information in the log 400.

The location information generation module 395 is configured to generate location information to append to image files that have been captured by a non-GPS- equipped camera device. Referring to Fig. 7, in order to provide the navigation device 200 with access to the image files, either (i) a two-way data communication link is established between the I/O port 270 of the navigation device and the camera 280a or other storage device containing the image files (as an I/O device), or (ii) a memory card 280b containing the image files is inserted in the memory card port 270a of the navigation device 200. The file inspector module 292 permits the navigator to access the image files stored in a predetermined format.

The process of generating and appending the location information for the image files is typically initiated in response to a user command or confirmation inputted via the input device 220, although the process could be initiated automatically when the connection to the camera 280a or memory card 280b is established. Fig. 8 depicts schematically the steps of the process of generating and appending the location information. At step 420, an image file 425 is accessed to read the date and time information 430 associated with the file 425. The image file 425 may be a still image file or a moving image file. Nearly all modern digital cameras include a built-in clock for recording date and time information as date-time metadata 430 representing the date and time at which the image is captured and/or the image file created. If at step 435 no date and no time information is located for the image file, then either the process stops for that image file, or process jumps to step 485 described below.

The next steps function to obtain the best estimate of the location information that matches the date and time information 430. At step 440, the date and time information 430 is compared to the current date and time information in the navigation device 200. If the date and time information 430 is not older than a first predetermined time interval compared to the current date and time, the current position of the navigation device is considered close enough to use as the location information. The process proceeds to step 445 to select the current location of the navigation device as the location information for the image file. The first predetermined interval may be of the order of a few minutes, for example, up to 5 minutes, or up to 10 minutes. The process then proceeds to step 450 described below for appending the location information to the image file. Alternatively, at step 455 the log 400 is accessed to retrieve the log entries that are closest in time to the date and time information 430. Optionally the log entries sandwich the date and time information 430. At step 460, the time interval between the date and time information 430, and the date-time pair 405 of each retrieved log entry, is evaluated and compared to a second interval (first threshold) to assess whether both retrieved log entries are close in time to the date and time information 430. The second interval may also be of the order of a few minutes, for example, up to 5 minutes, or up to 10 minutes, or 15 minutes. If both log entries are sufficiently close in time to the date and time information 430, the process proceeds to interpolation step 465. At step 465, the respective location data 410 for the two date-time pairs 405 is retrieved, and interpolation is performed to generate position information 500 intermediate the respective location data 410. Various interpolation processes may be used. Fig. 9 illustrates, by way of example only, linear interpolation between two location data points 410a and 410b. The linear ratio between the date-time information 430 and each of the respective date-time pairs 405 in the time domain, is used to derive a corresponding location point 500 that lies between the location data points according to the same ratio in the location domain. Linear interpolation may also be used to project location points that do not sandwich the date and time information 430. Other interpolation processes are also contemplated, for example, non-linear interpolation, or interpolation along a predetermined navigation route. The process then proceeds to step 450 described below for appending the location information to the image file. Alternatively, at step 470, the retrieved log entries are again analysed to assess whether one of the log entries is close in time to the date and time information 430. The difference between the date-time pair 405 of each log entry, and the date and time information, may be compared to a third interval (second threshold). The third interval may be the same as the second interval, or different. The third interval may also be of the order of a few minutes, for example, up to 5 minutes, or up to 10 minutes, or 15 minutes. The calculation results from step 460 may be re-used if appropriate. If at step 470, one of the retrieved log entries is determined to be sufficiently close, the process proceeds to step 475 to select the location data 410 corresponding to that retrieved log entry. The process then proceeds to step 450 described below for appending the location information to the image file.

Should the process arrive at step 480, this indicates the log entries are not sufficiently close to the date and time information 430 of the image file 425 for the process automatically to determine location information with confidence. At step 480, both of the log entries closest in time are displayed as suggestions for the user to choose between.

At step 485, the user is prompted to input manual information from which location information may be generated. For example, the user may be prompted to select one of the suggested locations from step 480, or the current location of the navigation device, or to input another location by any method by which the navigation device accepts location information for navigation assistance (for example, by means of a post-code, or by means of an road name and address, or by means of manual selection from a graphical map). At step 490, location information corresponding to the user's input is generated, and the process proceeds to step 450.

At step 450, the location information is appended to the image file 425. If the file format already includes an empty placeholder field for the location information, the generated location information may be written directly into the file without modifying other contents of the file. If the file format does not already include a placeholder field, the location information is appended to the file contents, and the file is re-saved to the camera 280a or memory card 280b, overwriting the original copy of the image file.

At step 495, the process checks to see whether all image files have been processed. If not, the process returns to step 420 to repeat the process for a next image file.

It will thus be appreciated that the preferred embodiment can enable location information to be generated automatically for image files that have recently or previously been captured by a non-PS-equipped camera device. One way of doing this used by the preferred embodiment is to correlate date and time information associated with the image file, with a log of location information recorded by the navigation device.

In a possible modification of the above described embodiment, the navigation device may be further configured to display markers on a map display, the markers corresponding to the location information that is generated. Markers may also be displayed for other image files that already contain location information in a recognised format.

Although the embodiment has been described in terms of a navigation device (e.g. a device that also includes route planning and navigation functionality), it will be appreciated that the same principles may be employed by any PS-equipped apparatus that is able to access image files on a camera or a storage device. The navigation functionality may be additionally useful in interpolating the log of recorded position data along a navigation route, but navigation functionality is not an essential feature in all embodiments.

It will be appreciated that whilst various aspects and embodiments of the present invention have heretofore been described, the scope of the present invention is not limited to the particular arrangements set out herein and instead extends to encompass all arrangements, and modifications and alterations thereto, which fall within the scope of the appended claims.

It should also be noted that whilst the accompanying claims set out particular combinations of features described herein, the scope of the present invention is not limited to the particular combinations hereafter claimed, but instead extends to encompass any combination of features or embodiments herein disclosed irrespective of whether or not that particular combination has been specifically enumerated in the accompanying claims at this time.

Claims

1. Apparatus (200) comprising: a positioning system signal receiver (250); a processor (210); memory (230); a communication port (270); characterised by: a location data logging module (390) configured to cause the processor to record in the memory a log of location data, date and time, the location data being derived from the positioning system signal receiver, and the log representing variation of the location data at different instants in time; a file inspector module (392) configured to cause the processor to inspect an image file accessible to the apparatus via the communication port; and a location information generation module (395) configured to cause the processor to generate, using the log, location information for the image file.

2. The apparatus of claim 1 , further comprising a navigation module configured to cause the processor to execute navigation assistance responsive to an electronically stored map, and a current location derived from the received positioning system signals.

3. The apparatus of claim 1 or 2, wherein: the file inspector module (392) is configured to cause the processor to inspect date and time information associated with said image file, and the location generation module (395) is configured to cause the processor to use the date and time information associated with file, to generate said location information.

4. The apparatus of claim 3, wherein the location generation module (395) is configured to cause the processor to retrieve at least one entry in the log, said at least one entry being closest in time to the date and time information associated with the image file.

5. The apparatus of claim 4, wherein the number of closest retrieved entries is two.

6. The apparatus of claim 3 or 4, wherein the retrieved entries includes a log entry before, and a log entry after, the date and time information for the image file.

7. The apparatus of claim 4, 5 or 6, wherein the location generation module (395) is configured to cause the processor to generate the location information from the location data of the at least one retrieved closest log entry.

8. The apparatus of claim 7, wherein the location generation module (395) is configured to cause the processor to calculate location information for the image file, by interpolation of the location data of the at least one retrieved log entry.

9. The apparatus of claim 8, wherein the location generation module (395) is configured to calculate by interpolation if the time difference between the date and time information for the image file, and each of the at least one retrieved log entry, is less than a first threshold.

10. The apparatus of claim 7, 8 or 9, wherein the location generation module (395) is configured to cause the processor to select the location data for the closest of the retrieved log, responsive to the date and time information for the image file being the same as, or less than a second threshold interval different from, the date and time information for the closest retrieved log entry.

11. The apparatus of any preceding claim, wherein the location generation module (395) is further configured to cause the processor to append the location information to the image file via a file writing operation using the communication port.

12. The apparatus of any preceding claim, wherein the location information comprises GPS coordinate metadata for the image file.

13. A navigation device (200) comprising: a positioning system signal receiver (250); a processor (210); a file inspector module (392) configured to cause the processor to inspect an image file accessible to the navigation device via the communication port; characterised by: memory (230) storing a log of location data, date and time, the location data being derived from the positioning system signal receiver, and the log representing variation of the location data at different instants in time; and a location information generation module (392) configured to cause the processor to generate, using the log, location information for the image file.

14. A method of operation of an apparatus equipped with a positioning system signal receiver, the method comprising the steps of: calculating location data representing a location of the apparatus at an instant in time; characterised by: recording a log of location data, date and time, the log representing variation of the location data at different instants in time; accessing (420) a storage medium via a communication port of the apparatus, to access an image file stored on the storage medium; and generating (435-490), using the log, location information for the image file.

15. The method of claim 14, wherein: the step of accessing (420) comprises date and time information associated with said image file, and the step of generating comprises using the date and time information associated with file, to generate said location information.

16. The method of claim 15, wherein the step of generating comprises retrieving (455) a least one entry in the log, said at least one entry being closest in time to the date and time information associated with the image file.

17. The method of claim 16, wherein the number of closest retrieved entries is two.

18. The method of claim 16 or 17, wherein the retrieved entries includes a log entry before, and a log entry after, the date and time information for the image file.

19. The method of claim 15, 16 or 17, wherein the step of generating comprises generating (465, 475) the location information from the location data of the at least one retrieved closest log entry.

20. The method of claim 19, wherein the step of generating comprises calculating (465) location information for the image file, by interpolation of the location data of the at least one retrieved log entry.

21. The method of claim 20, wherein the step of generating comprises calculating by interpolation if the time difference between the date and time information for the image file, and each of the at least one retrieved log entry, is less than a first threshold.

22. The method of claim 19, 20 or 21, wherein the step of generating comprises selecting (475) the location data for the closest of the retrieved log, responsive to the date and time information for the image file being the same as, or less than a second threshold interval different from, the date and time information for the closest retrieved log entry.

23. A method of providing location information for an image file created without location information, the method characterised by the steps of: providing a log of location data, date and time, the location data being derived from a positioning system signal receiver, and the log representing variation of the location data for an apparatus at different instants in time; accessing (420) the image file to read the date and time associated with the image file; and using (460, 470) the date and time information associated with the image file to retrieve at least one entry, amongst plural entries in the log, having a date and time that is relatively closest in time to the date and time information associated with the image file; and generating (465, 480) location information for the image file responsive to the location data corresponding to each retrieved log entry.

24. Computer software configured to cause a processor to execute a method characterised by the steps of: providing a log of location data, date and time, the location data being derived from a positioning system signal receiver, and the log representing variation of the location data for an apparatus at different instants in time; accessing (420) the image file to read the data and time associated with the image file; and using (460, 470) the date and time information associated with the image file to retrieve at least one entry, amongst plural entries in the log, having a date and time that is relatively closest in time to the date and time information associated with the image file; and generating (465, 480) location information for the image file responsive to the location data corresponding to each retrieved log entry.

25. The computer software of claim 24, wherein the step of providing the log comprises: calculating location data representing a location of the apparatus at an instant in time, the location being derived from received positioning system signals; and recording the log of location data, date and time, the log representing variation of the location data at different instants in time.