Abstract:
A portable terminal is configured to perform method for feature recognition. The portable terminal includes a Global Positioning System (GPS), a camera, a sensor, an image geographic information part, an image processor, and a controller. The GPS provides a position of the portable terminal. The camera photographs an image of a feature. The sensor detects a direction of the camera. The image geographic information part stores an image of each feature and geographic information on each feature. The image processor extracts a characteristic of the image of the feature and compares the extracted characteristic with image information stored in the image geographic information part. If recognizing a specific feature through the image processor, the controller proportionally compares geographic information of the image geographic information part with size and direction data on a peripheral feature near the specific feature within an image, and recognizes the peripheral feature.

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY 
       [0001]    The present application is related to and claims priority under 35 U.S.C. §119(a) to a Korean Patent Application filed in the Korean Intellectual Property Office on Nov. 27, 2008 and assigned Serial No. 10-2008-0119178, the contents of which are herein incorporated by reference. 
       TECHNICAL FIELD OF THE INVENTION 
       [0002]    The present invention relates to a method for providing geographic information using a camera and a Global Positioning System (GPS) in a mobile communication terminal. More particularly, the present invention relates to a method for recognizing a feature using a camera of a mobile communication terminal and, when displaying information on the recognized feature in a real image, providing information on a feature around the recognized feature using a position of the recognized feature and direction information in which a user looks. 
       BACKGROUND OF THE INVENTION 
       [0003]    GPS is the abbreviation of a global positioning system developed by the Pentagon. The GPS includes a plurality of GPS satellites and a GPS receiver. The plurality of GPS satellites are arranged by four in each of six circular orbits of an inclination angle of 55° . The plurality of GPS satellites transmits their own position information signals while moving in a cycle of about 12 hours. The GPS receiver receives position information signals from at least four or more GPS satellites among the plurality of GPS satellites, detects its distances from the GPS satellites and position vectors of the GPS satellites, and calculates its own position vector. A navigation system including the GPS receiver maps its own position vector calculated from the GPS receiver on map data, and displays the mapped position vector. The navigation system provides, as a supplementary service, a road guidance service for informing the shortest path from a current position on a map to a user&#39;s destination. Therefore, a user can more easily find a way to her own destination by carrying the navigation system. 
         [0004]      FIG. 1  illustrates a block diagram of a construction of a portable terminal for recognizing an image using a camera according to the conventional art. As illustrated in  FIG. 1 , a navigation system is integrated with a camera  104 . The navigation system can include a command input part  112 , a GPS receiver  100 , a map data storage part  108 , a sensor  110 , an image processor  106 , and a controller  102 . The command input part  112  receives an input of a user&#39;s operation command. The GPS receiver  100  receives a position information signal transmitted by a GPS satellite. The map data storage part  108  stores map data. The sensor  110  detects a direction angle of the camera  104  and an inclination angle through a geomagnetic sensor and an angle meter. The image processor  106  processes an image captured by the camera  104 . The controller  102  captures an image photographed by the camera  104  at a predetermined time interval, searches the map data storage part  108  for buildings of position information consistent with respective buildings within the captured image, and matches them with each other. 
         [0005]    However, the conventional art has a disadvantage of consuming much time because having to display geographic information on several features. In this case, the portable terminal has to recognize one feature and display geographic information and, after that, again recognize a next feature and display geographic information. In theory, assuming that number of features required to display geographic information is equal to ‘n’ and a time taken to recognize one feature is equal to ‘t’, a time taken to display geographic information on the total features is equal to ‘n*t’. However, because the ‘t’ can be a long time, a user has to spend much time to obtain interested information. 
       SUMMARY OF THE INVENTION 
       [0006]    To address the above-discussed deficiencies of the prior art, it is a primary object to provide at least the advantages below. Accordingly, one aspect of the present invention is to recognize a user&#39;s current position using a Global Positioning System (GPS), recognize a specific feature using a camera, and provide geographic information around the specific feature using position information on the recognized feature and direction information of the camera input from a sensor. In this case, upon recognition of only an initial feature, geographic information on the feature can be easily displayed using previously stored data. 
         [0007]    The above aspects are achieved by providing a method for feature recognition in a mobile communication terminal. 
         [0008]    According to one aspect of the present invention, a portable terminal is provided. The portable terminal includes a GPS, a camera, a sensor, an image geographic information part, an image processor, and a controller. The GPS provides a position of the portable terminal. The camera photographs an image of a feature. The sensor detects a direction of the camera. The image geographic information part has an image of each feature and geographic information on each feature. The image processor extracts a characteristic of the image of the feature obtained in the camera and compares the extracted characteristic with image information stored in the image geographic information part. If recognizing a specific feature through the image processor, the controller proportionally compares geographic information of the image geographic information part with size and direction data on a peripheral feature near the specific feature within an image, and recognizes the peripheral feature. 
         [0009]    The camera may capture an image if there is no motion for a predetermined time. 
         [0010]    The sensor can include a geomagnetic sensor. 
         [0011]    The image geographic information part can include width and height information on the feature. 
         [0012]    According to another aspect of the present invention, a method for feature recognition in a portable terminal is provided. The method includes recognizing a current position of the portable terminal by a GPS, photographing an image of a feature by a camera, detecting a direction of the camera using a sensor, extracting a characteristic of the image of the feature photographed by the camera and comparing the extracted characteristic with image information on a feature positioned in a direction of the camera on a position of the portable terminal and, if recognizing a specific feature, comparing geographic information of an image geographic information part with distance and direction data on a peripheral feature near the specific feature within an image, and recognizing the peripheral feature. 
         [0013]    Before undertaking the DETAILED DESCRIPTION OF THE INVENTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]    For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
           [0015]      FIG. 1  illustrates a block diagram of a construction of a portable terminal for recognizing an image using a camera according to the conventional art; 
           [0016]      FIG. 2  illustrates a block diagram of a construction of an image recognition portable terminal according to an exemplary embodiment of the present invention; 
           [0017]      FIG. 3  illustrates a diagram for an operation screen of an image recognition portable terminal according to an exemplary embodiment of the present invention; 
           [0018]      FIG. 4  illustrates a flow diagram for a method for matching of geographic information on a feature between an image captured by a camera and image data stored in an image data storage part according to an exemplary embodiment of the present invention; 
           [0019]      FIG. 5  illustrates a diagram for a process of matching based on a size rate between a real feature and a photographed image in  FIG. 4 ; and 
           [0020]      FIGS. 6A and 6B  illustrate diagrams of screens for recognizing a feature when photographing the feature in opposite positions. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]      FIGS. 2 through 6B , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged mobile terminal. 
         [0022]      FIG. 2  illustrates a block diagram of a construction of an image recognition portable terminal according to an exemplary embodiment of the present invention. 
         [0023]    Referring to  FIG. 2 , the portable terminal includes a controller  201 , a GPS  202 , a camera  203 , a sensor  204 , an image processor  205 , an image data storage part  206 , and a Liquid Crystal Display (LCD)  207 . The GPS  202  can recognize a user&#39;s current position. The camera  203  can recognize a real image. The sensor  204  can detect a motion and direction of the terminal, i.e., the camera  203 . The image processor  205  can extract a characteristic of a captured image, and can compare the characteristic with image data stored in the image data storage part  206 . The image data storage part  206  is operable to store image data on each feature and geographic information on the feature. The controller  201  can control each part. The LCD  207  displays the real image and the geographic information. 
         [0024]    The GPS  202  is able to recognize a user&#39;s current position. User position information is used to reduce an amount of comparison-target data stored in the image data storage part  206  at the time of image recognition through the camera  203 . That is, the position information is used to reduce a time consumed for image recognition by, upon image recognition, not comparing with all data in the image data storage part  206  but comparing a recognized image with only data on the vicinity of the current position recognized by the GPS  202 . 
         [0025]    The controller  201  can capture an image using the camera  203  when determining that there is no motion of the terminal for a predetermined time using motion information on the terminal input from the sensor  204 . The controller  201  compares the captured image with image data previously stored in the image data storage part  206  through the image processor  205 , and detects geographic information on a captured feature. 
         [0026]    The sensor  204  includes an acceleration sensor and a geomagnetic sensor. The sensor  204  is attached to the terminal and thus, can detect a direction of the terminal, for example, a direction of the camera  203 , and can also measure an attitude of the terminal. When determining that there is no change of the attitude of the terminal for a predetermined time using attitude information on the terminal, the controller  201  determines that a user is concerned about a specific feature photographed by the camera  203  at this time and captures an image of this time. Also, the sensor  204  detects a direction corresponding to this time through the geomagnetic sensor and, later on, uses the detected direction for information matching with a peripheral feature. 
         [0027]    The image data storage part  206  can stores image data on each feature, and can include position information and name information corresponding to each feature. Thus, the image data storage part  206  compares an image of a specific feature captured by the camera  203  with a previously stored image, and detects a name and position of the captured image. Particularly, the image data storage part  206  includes 3-Dimensional (3D) information (width and height information) on a feature. Thus, if an image is recognized through the camera  203 , the controller  201  compares previously stored width information with width information displayed on a screen and calculates how far a real distance per pixel of the screen is. At this time, the image data storage part  206  detects information on a peripheral feature near the specific feature using the detected position information on the specific feature. 
         [0028]    Also, the controller  201  can calculates a real distance between the detected position of the specific feature, which is a standard, and the peripheral feature. Thereafter, the controller  201  converts the real distance between the standard feature and the peripheral feature into a distance on the screen. At this time, the controller  201  can convert the real distance between the two features into the distance on the screen using information on the previously calculated real distance per pixel. The controller  201  matches geographic information on the peripheral feature to a real image using the calculated distance information on the screen from the standard feature on the screen. 
         [0029]      FIG. 3  illustrates an example operation screen of the present invention. A GPS recognizes a user&#39;s current position. Thereafter, if a camera recognizes a building of “Digital Research Institute” that is a standard feature through an image processor, a controller matches an indication named “Information Communication Research Institute” to a real image using direction information input from a sensor and position information on the two buildings loaded from an image data storage part. 
         [0030]      FIG. 4  illustrates a flow diagram for a method for matching of geographic information on a feature between an image captured by a camera and image data stored in an image data storage part according to an exemplary embodiment of the present invention. 
         [0031]    In step  401 , if a mobile communication terminal user powers on a GPS receiver included in a mobile communication terminal, the GPS recognizes a user&#39;s current position. 
         [0032]    Thereafter, while the user photographs a peripheral feature using a camera, a sensor recognizes if the user photographs a specific feature for a predetermined time, i.e., the sensor determines that there is no change of an attitude of the camera through a sensor, and a controller captures an image of the specific feature. At this time, if the sensor does not determine a non-change of an attitude of the camera (i.e., there is no stop determination), the controller determines that the user is not concerned in the specific feature, and does not capture an image. (steps  403  to  407 ) 
         [0033]    Then, if the controller captures the image of the specific feature, in step  409 , an image processor extracts a characteristic of the specific feature. 
         [0034]    The controller compares the extracted characteristic of the specific feature with image information stored in the image data storage part, and loads geographic information on the captured specific feature. Then, the controller uses only data on a peripheral feature that is in the vicinity of the user&#39;s current position for image recognition using the user&#39;s current position information. The controller acquires name, position, width, and height information on a feature stored in the image data storage part. When this process is completed, the feature becomes a standard feature. 
       (Steps  411  to  415 ) 
       [0035]    Then, the controller compares width and height information on the standard feature with width and height information on a screen and calculates a real distance indicated by one pixel on the screen.  FIG. 5  illustrates the above process. If a “Digital Research Institute” is recognized as a standard feature, the controller extracts (x s , y s ), w s , l s , and h s  , and loads (x  r  , y r ), w r , l r , and h r  from the image data storage part. At this time, the controller compares the w s , l s , and h s  with the w r , l r , and h r  and calculates a real distance indicated by one pixel of the screen. Then, the controller loads real coordinates (x r ′, y r ′), w r ′, l r ′, and h r ′ of an “Information Communication Research Institute” that is information on a peripheral feature around the (x r , y r ). Then, the controller calculates dist s  using dist r  and the previously calculated real distance information per one pixel. Lastly, the controller calculates the (x s ′, y s ′) using the user direction information and the dist s  on the basis of the (x s , y s ) (steps  417  to  425 ) 
         [0036]      FIGS. 6A and 6B  illustrate a simple concept of calculating coordinates (x s ′, y s ′) . In an example, it is assumed that, when user direction information is equal to 0° , i.e., in a state where a user directs to due north, an object (B) having screen coordinates (x s ′, y s ′) is a feature located on the left of an object (A) having screen coordinates (x s , y s ) as shown in  FIG. 6A . However, when the user direction information is equal to 180° , unlike when the user direction information is equal to 0°, the feature (B) is positioned and output on the right of the object (A) on a screen. This is because a position of a peripheral feature positioned on the screen centering on a standard feature is varied depending on a user&#39;s position and direction. By this method, the controller can detect whether the peripheral feature is positioned on the right or left of the standard feature on the screen using the user direction information. 
         [0037]    Lastly, the controller outputs geographic information on the peripheral feature in the calculated coordinates (x s ′, y s ′), thereby being capable of matching the geographic information on the peripheral feature to a real image. 
         [0038]    The present invention simply photographs a feature without a user&#39;s specific operation command and therefore, captures an image and matches not only geographic information on the captured feature but also geographic information on a peripheral feature to a real image, thus having an advantage that a user can easily recognize a feature. 
         [0039]    Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.