Patent Publication Number: US-7903171-B2

Title: Notebook information processor and image reading method

Description:
RELATED APPLICATIONS 
     The present application is based on, and claims priority from, Japanese Application No. 2008-110612, filed Apr. 21, 2008, the disclosure of which is hereby incorporated by reference herein in its entirety. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a notebook information processor and an image reading processing method. 
     2. Description of the Related Art 
     With a notebook information processor such as conventional PDA terminal and laptop type PC, by way of example, when a user such as a businessman wants to scan a document such as a paper document not at his desk in an office with a well-equipped environment but at a meeting, when visiting a customer, and in a hotel of a business trip destination, it is required to additionally bring a portable scanner or a digital camera. 
     When additionally bringing the portable scanner, a general commercially available notebook information processor and a portable scanner weigh about 1 to 2 kg and 1.4 kg, respectively, so that they weigh about 3 kg in total and are too heavy for the user to bring. In addition, the user has to keep an installation area of both the notebook information processor and the scanner when scanning. 
     On the other hand, when using the digital camera in place of the portable scanner, since a compact digital camera weighs about 0.1 to 0.2 kg, for example, weight thereof is not increased so much. However, in this case, it is required to keep an installation area of the notebook information processor and a space to put document such as a paper document to be photographed on. In addition, it is difficult to straightforwardly photograph the document without using a tripod or the like, so that it is required to convert the document photographed by the digital camera as if this is straightforwardly photographed and to perform cropping to clip the document from a background. 
     Therefore, recently, the notebook information processor having a scanner function has been developed as a portable image input device. 
     For example, Japanese Patent Application Laid-open No. 2000-137544 discloses a notebook personal computer formed of the lid having a display and a main body having a keyboard, in which a PC card slot is placed on the lid side and the PC card camera is mounted on the PC card slot, and the PC card camera photographs a personal computer operator or the like. 
     Japanese Patent Application Laid-open No. 2000-194450 discloses an information processor with a document presenting device, in which an illuminating device supporting mechanism, an electric camera, and an electric camera supporting mechanism are added to a laptop personal computer, which is the information processor, so as not to change the external form and size of a casing thereof, and an image of the presented document photographed by using them is captured into the laptop personal computer. 
     Japanese Patent Application Laid-open No. 2002-539516 discloses a portable electric device in which a charge-coupled device camera is integrated with one wing portion of a portable personal computer and a record document such as a business card is fixed to the other wing portion with a clip or a transparent ribbon, and the charge-coupled device camera photographs the record document. 
     However, although the conventional portable image input device (Such as Japanese Patent Applications Laid-open Nos. 2000-137544, 2000-194450, and 2002-539516) may act as the notebook information processor having the scanner function, they require the installation area of the document or the like in addition to the installation area of the notebook information processor, and there is the problem in efficiency and accuracy in capturing the image. 
     Specifically, the conventional portable image input device requires the installation area of the document when capturing the document, and there is the problem that the photographing area may not be adjusted or checked in real time before capturing the image. The conventional portable image input device has the problem that the image processing may not be performed to the captured image so as to obtain the image of the document photographed from the front direction and clipped from the background. That is to say, there is the problem that the user has difficulty in obtaining the desired image in which the document photographed from the front direction is clipped from the background in real time. 
     For example, in the technology disclosed in Japanese Patent Application Laid-open No. 2000-137544, the PC card slot is placed in the display (lid) such that the PC card camera or the like inserted in the PC card slot does not block the personal computer operation, and the check of the installation area of the document and the photographing area when capturing the document and the image processing to transform to the image photographed from the front direction are not considered. 
     The technology disclosed in Japanese Patent Application Laid-open No. 2000-194450 is to form the document presenting device having the illumination device and the electric camera so as to be housed in the laptop personal computer and provide the installation area when capturing the document on the rear surface or the side surface of the laptop personal computer, and the check of the photographing area when capturing the document and the image processing to transform to the image photographed from the front direction are not considered. 
     The technology disclosed in Japanese Patent Application Laid-open No. 2002-539516 is such that the written document or the like to be photographed is fixed to one wing portion of the portable personal computer with the clip or the like, and the user photographs the photographing object by the camera integrated with the other wing portion by positioning the same to the optimal position to reduce defocus of the image, so that this requires fixing operation of the document or the like to be photographed and positioning of the optimal distance of the camera, and the check of the photographing area when capturing the document and the image processing to transform to the image photographed from the front direction are not considered. 
     That is to say, in the conventional portable image input device technology disclosed in Japanese Patent Applications Laid-open Nos. 2000-137544, 2000-194450, and 2002-539516, to obtain the image photographed from the front direction and in which the document is clipped, which the user desires, there is the problem in efficiency and accuracy when capturing the image that the user himself has to manually adjust the setting of the photographing direction and the focus of the camera, check the image after photographing, and photograph again when the desired image is not obtained. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to at least partially solve the problems in the conventional technology. 
     A notebook information processor according to one aspect of the present invention, includes an image photographing unit a display a keyboard a storage unit and a control unit, wherein the control unit includes a live view displaying unit that displays a live view obtained by photographing at least a portion of the keyboard within a photographing area of the image photographing unit on the display, a still image obtaining unit that obtains a still image from the live view displayed on the display by the live view displaying unit, when receiving a photographing start signal to start photographing the still image of a document put on the keyboard, and an image processing unit that performs projective transformation on the still image obtained by the still image obtaining unit so as to obtain an image photographed from a front direction, executes image processing so as to perform cropping to clip the document, and stores a transformed image of the document after the image processing in the storage unit. 
     A notebook information processor according to another aspect of the present invention, includes an image photographing unit, a display, a keyboard, a storage unit, and a control unit, wherein the control unit includes a live view displaying unit that obtains a live view obtained by photographing at least a portion of the keyboard within a photographing area of the image photographing unit, and performs projective transformation on the obtained live view so as to obtain the live view photographed from a front direction, thereby displaying the live view after the projective transformation on the display, a still image obtaining unit that obtains a still image from the live view displayed on the display by the live view displaying unit, when receiving a photographing start signal to start photographing the still image of a document put on the keyboard, and an image processing unit that executes image processing to the still image obtained by the still image obtaining unit so as to perform cropping to clip the document, and stores a transformed image of the document after the image processing in the storage unit 
     An image reading method according to still another aspect of the present invention is executed by a notebook information processor including an image photographing unit a display a keyboard a storage unit and a control unit. The method includes a live view displaying step of displaying a live view obtained by photographing at least a portion of the keyboard within a photographing area of the image photographing unit on the display, a still image obtaining step of obtaining a still image from the live view displayed on the display at the live view displaying step, when receiving a photographing start signal to start photographing the still image of a document put on the keyboard, and an image processing step of performing projective transformation on the still image obtained at the still image obtaining step so as to obtain an image photographed from a front direction, executing image processing so as to perform cropping to clip the document, and storing a transformed image of the document after the image processing in the storage unit. 
     An image reading method according to still another aspect of the present invention is executed by a notebook information processor, including an image photographing unit, a display, a keyboard, a storage unit, and a control unit. The method includes a live view displaying step of obtaining a live view obtained by photographing at least a portion of the keyboard within a photographing area of the image photographing unit, and performing projective transformation on the obtained live view so as to obtain the live view photographed from a front direction, thereby displaying the live view after the projective transformation on the display, a still image obtaining step of obtaining a still image from the live view displayed on the display at the live view displaying step, when receiving a photographing start signal to start photographing the still image of a document put on the keyboard, and an image processing step of executing image processing to the still image obtained at the still image obtaining step so as to perform cropping to clip the document, and storing a transformed image of the document after the image processing in the storage unit. 
     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a outline drawing showing one example of a configuration of the notebook information processor  100 ; 
         FIG. 2  is a flowchart showing one example of a basic process of the present invention; 
         FIG. 3  is a logical configuration block diagram showing one example of a configuration of the notebook information processor  100 ; 
         FIG. 4  is a view of an example when using the image photographing unit  116  as the WEB camera; 
         FIG. 5  is a view of an example of using the image photographing unit  116  as the scanner (scanner mode); 
         FIG. 6  is physical configuration diagram showing one example of a further configuration of the notebook information processor  100 ; 
         FIG. 7  is a view showing one example of a projective transformation according to the embodiment; 
         FIG. 8  is a view showing one example of the projective transformation according to the embodiment; 
         FIG. 9  is a view showing one example of images after the projective transformation and cropping according to the embodiment; 
         FIG. 10  is a flowchart showing one example of an image reading process of the notebook information processor  100  according to the embodiment; and 
         FIG. 11  is a flowchart showing one example of a photographing start signal generating process of the notebook information processor  100  according to the embodiment. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Embodiments of a notebook information processor and image reading method and program, and a recording medium according to the present invention will be explained below with reference to the accompanying drawings. The present invention is not limited to the embodiment. 
     Outline of the Present Invention 
     An outline of the present invention will be explained below. Thereafter, configurations, processes, and the like of the present invention will be explained below in detail with reference to the  FIGS. 1 and 2 . 
     The present invention generally has the following basic characteristic features. 
     As shown in  FIG. 1 , the notebook information processor  100  is highly portable and does not require an installation area for capturing a document or the like, so that the notebook information processor  100  incorporating an image photographing unit  116  (WEB camera) is used as a virtual scanner device. 
     In  FIG. 1 , the image photographing unit  116  (WEB camera) acts as an image input unit, which has a scanner function. A lid  1  (display casing) acts as a camera stand that fixes the image photographing unit  116 . A display  114  (display) is used as a monitor screen that displays a live view to be explained later, as an auxiliary light source, and to reproduce a stored image. A keyboard  112  on a main body  2  acts as a document table of the virtual scanner device. Thus the configured notebook information processor  100  may have the scanner function with minimum device weight and installation area. 
     That is to say, the notebook information processor  100  according to this invention is composed of, for example, the lid  1  (display casing) including at least the image photographing unit  116  and the display  114 , and the main body  2  including at least the keyboard  112 , a storage unit, and a control unit. 
     In the present invention, the image photographing unit  116  may be detachably placed in the notebook information processor  100 , and this may be electrified by the notebook information processor  100  and communicatably connected to the notebook information processor  100 . The image photographing unit  116  may be rotatably placed in the notebook information processor  100  so as to be able to change a photographing direction thereof. 
     The notebook information processor  100  may further include a rotation angle sensor that detects a rotation angle when rotating the image photographing unit  116  to change the photographing direction thereof. The notebook information processor  100  may include the lid  1  in which at least the image photographing unit  116  is placed, and the main body  2  in which at least the keyboard  112  is placed, and may further include an open angle sensor that detects an open angle of the lid  1  with respect to the main body  2 , and a motor that adjusts the rotation angle of the image photographing unit  116 . 
     The control unit of the notebook information processor  100  may adjust the rotation angle of the motor so as to adjust the photographing direction of the image photographing unit  116 , based on the open angle detected by the open angle sensor. 
     As shown in  FIG. 2 , the control unit of the notebook information processor  100  displays a live view obtained by photographing at least a portion of the keyboard  112  within a photographing area of the image photographing unit  116  on the display  114  (Step SA- 1 ). 
     The “live view” is a moving image and a still image photographed by the image photographing unit  116 , displayed on the display  114  such that a user may check in real time for adjusting the photographing area of the image photographing unit  116 . 
     The control unit of the notebook information processor  100  may obtain the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area of the image photographing unit  116 , and perform a projective transformation on the obtained live view so as to obtain the live view photographed from a front direction, thereby displaying the live view after the projective transformation on the display  114 . 
     The control unit of the notebook information processor  100  obtains a still image from the live view displayed on the display  114 , when receiving a photographing start signal to start photographing the still image of the document put on the keyboard  112  (Step SA- 2 ). 
     The “document” is a photographing object (subject) of the still image by the image photographing unit  116 , and includes not only a planar one such as a paper document but also a stereoscopic one. 
     The control unit of the notebook information processor  100  may determine presence of the document by comparing a first image in which the document is not on the keyboard  112  and a second image in which the document is on the keyboard  112  obtained by the image photographing unit  116 , and when there is the document, this may generate the photographing start signal to transmit. 
     The control unit of the notebook information processor  100  may adjust brightness of the display  114  when obtaining the still image at a still image obtaining process (Step SA- 2 ). That is to say, the control unit of the notebook information processor  100  temporally changes the brightness of the display  114  when photographing the document and uses the display  114  as an auxiliary light source. 
     The control unit of the notebook information processor  100  performs the projective transformation on the obtained still image so as to obtain the image photographed from the front direction, executes image processing so as to perform cropping to clip the document, and stores the transformed image of the document after the image processing in the storage unit (Step SA- 3 ). When displaying the live view after the projective transformation on the display  114  at Step SA- 1 , the control unit of the notebook information processor  100  may execute the image processing to the obtained still image so as to perform the cropping to clip the document, and store the transformed image of the document after the image processing in the storage unit. 
     According to the present invention, in the cropping in the image processing (Step SA- 3 ), a corner of the document may be detected by comparing the first image in which the document is not on the keyboard  112  and the second image in which the document is on the keyboard  112  obtained by the image photographing unit  116 . 
     Configuration of Notebook Information Processor  100   
     A configuration of the notebook information processor  100  will be explained with reference to  FIGS. 3 to 9 . 
       FIG. 3  conceptually shows only parts related to the present invention. 
     As shown in  FIG. 3 , the notebook information processor  100  generally includes an image photographing unit  116 , a display  114 , a keyboard  112 , a storage unit  106 , a control unit  102 , a rotation angle sensor  118 , an open angle sensor  120 , a motor  122 , an input/output control interface unit  108 , and a communication control interface  104 . 
     In  FIG. 3  the control unit  102  is formed by a Central Processing Unit (CPU) which controls the notebook information processor  100  totally, or the like. The communication control interface  104  connects to a communication device (not shown) such as a router connected to a communication channel or the like, and the input/output interface unit  108  connected to the image photographing unit  116 , the display  114 , the keyboard  112 , the angle sensor  118 , the open angle sensor  120 , and the motor  122 . The storage unit  106  stores various databases and tables. The units composing the notebook information processor  100  are communicably connected through an optional communication channel. Further, the notebook information processor  100  is communicably connected to a network  300  via a communication device such as a router, and a wired or wireless communication line such as a dedicated line. 
     In  FIG. 3 , the image photographing unit  116  is a video camera or a digital camera that has a function to photograph the moving image for the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area, and is formed of, for example, a charge coupled device (CCD). The image photographing unit  116  may be incorporated in the notebook information processor  100 . The image photographing unit  116  may be detachably placed in the notebook information processor  100 , electrified by the notebook information processor  100 , and communicatably connected to the notebook information processor  100  (for example, a USB-connected WEB camera or digital camera may be used as the image photographing unit  116 ). 
     The image photographing unit  116  may be rotatably placed in the notebook information processor  100  such that a photographing direction is changeable. 
     An example of rotatably placing the image photographing unit  116  on the notebook information processor  100  so as to be able change the photographing direction thereof is explained with reference to  FIGS. 4 and 5 . 
       FIG. 4  is an example when using the image photographing unit  116  as the WEB camera. As shown in  FIG. 4 , the image photographing unit  116  (WEB camera) is generally incorporated in an upper portion of the lid  1  (display frame) of the notebook information processor  100 . The image photographing unit  116  (WEB camera) is generally used in, for example, a television conference and a video chat, and this is used for projecting a PC operator, which is a user. The PC operator generally faces the display  114  (display), so that when placing the photographing unit  116  in the upper portion of the lid  1  (display frame) such that the display  114  (display) plane is perpendicular to a light axis of the image photographing unit  116  (WEB camera) (that is to say, the display plane and a focus plane of the WEB camera are parallel to each other), an object as the WEB camera, such as the television conference and the video chat, is achieved. At that time, an open angle θ of the display  114  (display) plane is generally about 90 to 135 degrees. 
       FIG. 5  is an example of using the image photographing unit  116  as the scanner (scanner mode). As shown in  FIG. 5 , it is configured such that only the image photographing unit  116  (WEB camera unit) may be rotated in a state with the open angle θ to direct the light axis to the keyboard  112 . Thereby, not only the PC operator but also the document such as the document put on the keyboard  112  may be photographed. 
     Referring again to  FIG. 3 , the notebook information processor  100  may further have a rotational angle sensor  118  that detects a rotational angle when rotated so as to change the photographing direction of the image photographing unit  116 . The notebook information processor may have the lid  1  in which at least the image photographing unit  116  is placed, and the main body  2  in which at least the keyboard  112  is placed, and may further have an open angle sensor  120  that detects an open angle of the lid  1  with respect to the main body  2 , and a motor  122  that adjusts the rotational angle of the image photographing unit  116 . 
     An example of a configuration in which the notebook information processor  100  further includes the rotation angle sensor  118 , the open angle sensor  120 , and the motor  122  is explained with reference to  FIG. 6 . The rotational angle sensor  118  and the open angle sensor  120  have a function to detect a rotational angle γ of the image photographing unit  116  and an open angle θ of the notebook information processor  100 , and is, for example, a gyro sensor that detects an angular speed and the angle. The motor  122  has a function to rotate the image photographing unit  116 . 
     As shown in  FIG. 6 , when the user rotates the image photographing unit  116  (WEB camera) rotatably placed in the notebook information processor  100  so as to photograph a plane (document plane) of the keyboard  112 , the rotation angle sensor  118  detects a rotation angle γ of the image photographing unit  116 . The control unit  102  of the notebook information processor  100  may automatically launches scanning software to shift to the scanner mode. At that time, since a motion image photographed by the image photographing unit  116  is displayed on the display  114  (display) as the live view in real time, the user may adjust the angle of the image photographing unit  116  while looking at the display  114 . When the open angle sensor  120  such as an encoder detects the open angle θ of the display  114  (display), the control unit  102  of the notebook information processor  100  may calculate the rotation angle γ necessary for the image photographing unit  116  (WEB camera) to photograph the plane (document plane) of the keyboard  112  based on the open angle θ, and control to rotate the image photographing unit  116  (WEB camera) by the motor  122  or the like. The control unit  102  of the notebook information processor  100  may calculate the rotation angle γ using an equation: γ=(π−θ)/4 supposing that the open angle is θ in this embodiment. 
     In  FIG. 3 , the various databases and the various tables (such as an image database  106   a ) stored in the storage unit  106  are storage units such as fixed disk devices. The storage units store various programs, various tables, various databases, and the like used in various processes. 
     Out of each component of the storage unit  106 , the image database  106   a  stores various moving images and still images, and for example, stores the moving images and the still images after various image processings (such as the projective transformation and the cropping) by the control unit  102 , in addition to the moving image and the still image of the live view photographed by the image photographing unit  116 . 
     The communication control interface  104  controls communication between the notebook information processor  100  and a network  300  (or a communication device such as a router). That is to say, the communication control interface  104  has a function to communicate data to another terminal through a communication line. The communication control interface  104  may have a function to communicate data to the image photographing unit  116  detachably connected to the notebook information processor  100  through the communication line. 
     The input/output control interface  108  controls the keyboard  112 , the display  114 , the image photographing unit  116 , the rotation angle sensor  118 , an open angle sensor  120 , and a motor  122 . The keyboard  112  corresponds to the keyboard placed in the main body  2 , and the display  114  corresponds to the display (monitor) placed in the lid  1 . 
     The control unit  102  has an internal memory that stores a control program such as an operating system (OS), a program defining various procedures, and required data. The control unit  102  performs information processing for executing various processings by the programs or the like. The control unit  102  functionally and conceptually includes a live view displaying unit  102   a , a still image obtaining unit  102   b , an image processing unit  102   c , a photographing start signal generating unit  102   d , a brightness adjusting unit  102   e , and a rotation angle adjusting unit  102   f.    
     Out of them, the live view displaying unit  102   a  displays the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area of the image photographing unit  116  on the display  114 . The live view displaying unit  102   a  may obtain the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area of the image photographing unit  116  and perform the projective transformation on the obtained live view so as to obtain the live view photographed from the front direction, thereby displaying the live view after the projective transformation to be explained later on the display  114 . 
     The still image obtaining unit  102   b  obtains the still image from the live view displayed on the display  114  by the live view displaying unit  102   a , when receiving the photographing start signal to start photographing the still image of the document put on the keyboard  112 . 
     The image processing unit  102   c  performs the projective transformation on the still image obtained by the still image obtaining unit  102   b  so as to obtain the image photographed from the front direction, executes the image processing so as to perform the cropping to clip the document, and stores the transformed image of the document after the image processing in the image database  106   a . When the live view displaying unit  102   a  displays the live view after the projective transformation on the display  114 , the image processing unit  102   c  may execute the image processing on the still image obtained by the still image obtaining unit  102   b  so as to perform the cropping to clip the document, and store the transformed image of the document after the image processing in the image database  106   a . The image processing unit  102   c  may detect the corner of the document by comparing the first image in which the document is not on the keyboard  112  and the second image in which the document is on the keyboard  112  obtained by the image photographing unit  116 , as the cropping. 
     The projective transformation performed by the image processing unit  102   c  and the live view displaying unit  102   a  are explained with reference to  FIGS. 7 and 8 . 
     The projective transformation performed by the image processing unit  102   c  and the live view displaying unit  102   a , for example, is executed by restoring the image photographed by the image photographing unit  116  to an original state by using an inverse projective transformation. An example of the projective transformation is explained below. When performing the projective transformation, a vanishing point of the image on an imaging plane  70  being an image plane photographed by the image photographing unit  116  is obtained. For example, when an imaging plane shape  71  being an image shape on the imaging plane  70  is the rectangle as shown in  FIG. 7 , the two vanishing points S 1  and S 2  are obtained. The vanishing point is the point at which extended lines of two straight lines, which are formed parallel in an actual shape, cross to each other, when projecting a predetermined shape. By thus obtaining the vanishing point, an original size before the projection and the projective transformation parameters being the parameters when performing the projective transformation are obtained based on the vanishing point, and the projective transformation is performed using a following [Equation 1]. That is to say, the projective transformation is performed by obtaining a coordinate (u,v,1) after the projective transformation from a coordinate (x,y,1) before the projective transformation by the [Equation 1]. 
     
       
         
           
             
               
                 
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     By thus performing the projective transformation on the coordinate of the imaging plane shape  71 , which is the coordinate before the projective transformation, a projectively transformed shape  75 , which is the shape after the projective transformation, may be obtained as shown in  FIG. 8  by obtaining the coordinate after the projective transformation. The projectively transformed shape  75  is similar to an original shape  76 , which is the shape when seeing the original imaged by the image photographing unit  116  from the front direction, that is to say, the shape when seeing the imaged plane in the vertical direction. 
     That is to say, in this embodiment, since the image photographing unit  116  does not photograph the document such as the paper document from the front direction, the photographed image of the document such as the paper document is distorted. For the distorted image, the image processing unit  102   c  and the live view displaying unit  102   a  correct the distortion by performing the projective transformation, further perform the cropping (trimming) to clip the document from a background, and store the document in the storage unit  106 . At that time, the image processing unit  102   c  may display the transformed image after the image processing on the display  114  (display). As explained above, the projective transformation by the image processing unit  102   c  may be to perform the image processing together with the cropping to be explained later after obtaining the image by the still image obtaining unit  102   b , or to successively perform the projective transformation processing to the image transferred from the image photographing unit  116  (WEB camera) by the live view displaying unit  102   a  to display the image on the display  114  as the live view. In this case, the user may look at the image as if photographed from the front direction, so that the document may be set more naturally. Various conventional technologies other than the above-described technique may be used as the projective transformation. 
     An example of the cropping performed by the image processing unit  102   c  is explained with reference to  FIG. 9 . 
     As shown in  FIG. 9 , in this embodiment, the image processing unit  102   c  may execute the projective transformation and the cropping (trimming) by displaying the still image obtained by the still image obtaining unit  102   b  on the display  114  (display), and by the user specifying four corners of the document such as the paper document by means of an input unit (not shown) such as a mouse. The image processing unit  102   c  extracts a borderline between the document such as the paper document and the plane of the keyboard  112  from brightness information or the like obtained from the still image, performs linear interpolation or the like to the extracted borderline, and calculates the four corners of the document, thereby executing the projective transformation and the cropping (trimming). The image processing unit  102   c  may photograph in advance the keyboard  112  before setting the document on the keyboard  112  by the image photographing unit  116 , extracts an area in which difference in the brightness information or the like with that of the still image obtained by the still image obtaining unit  102   b  reaches a certain level, performs the linear interpolation or the like to the extracted borderline, and calculates the four corners of the document, thereby executing the projective transformation and the cropping (trimming). Various conventional technologies other than the above-described technique may be used as the cropping. 
     Referring again to  FIG. 3 , the photographing start signal generating unit  102   d  generates the photographing start signal to start photographing the still image of the document put on the keyboard  112 . 
     The photographing start signal generating unit  102   d  may generate the photographing start signal by allowing the user to click an icon such as “shutter” displayed on the display  114  by means of the input unit (not shown) such as the mouse to transmit the signal to the still image obtaining unit  102   b . The photographing start signal generating unit  102   d  may generate the photographing start signal by detecting a specific sound input by the user by means of the input unit (not shown) such as a microphone incorporated in the notebook information processor  100  to transmit the signal to the still image obtaining unit  102   b.    
     The photographing start signal generating unit  102   d  determines presence of the document by comparing the first image in which the document is not on the keyboard  112  and the second image in which the document is on the keyboard  112  obtained by the image photographing unit  116 , and when there is the document, the photographing start signal generating unit  102   d  may generate the photographing start signal to transmit the signal to the still image obtaining unit  102   b.    
     The brightness adjusting unit  102   e  adjusts the brightness of the display  114  when obtaining the still image by the still image obtaining unit  102   b.    
     In this embodiment, although an environment light such as an interior light placed in an office or the like is used as the light to illuminate the keyboard  112  on which the document is put, light of the display  114  (display) of which brightness is adjusted by the brightness adjusting unit  102   e  may be used as the auxiliary light. That is to say, the brightness adjusting unit  102   e  sets an entire screen of the display  114  to a certain image (such as a full white screen with maximum brightness) at the time that the still image obtaining unit  102   b  receives the photographing start signal (image obtaining trigger) generated by the photographing start signal generating unit  102   d , thereby illuminating the document such as the paper document on the keyboard  112 . When the open angle θ of the display  114  (display) is, for example, equal to or larger than 90 degrees, the light of the display  114  (display) is never reflected by the document such as the paper document to appear (that is to say, glares), so that it is possible to use the light of the display  114  (display) of which brightness is adjusted by the brightness adjusting unit  102   e  as an excellent auxiliary light source. 
     The rotation angle adjusting unit  102   f  adjusts the rotation angle γ of the motor  122  so as to adjust the photographing direction of the image photographing unit  116 , based on the open angle θ detected by the open angle sensor  120 . 
     In this embodiment, for example, with the image photographing unit  116  (camera) of about 5-million pixel or higher, a practically sufficient level of quality of the image photographed by the image photographing unit  116  may be obtained as a document scanner. Although the notebook information processor  100  according to this embodiment is supposed to be used, for example, by the user such as the businessman, outside such as in a hotel of a business trip destination and when visiting a customer, the advantage in the installation area and simple operation are not lost even when this is used at his desk in an office or the like. 
     Process of Notebook Information Processor  100   
     An example of the image reading process of the process of the notebook information processor  100  according to the embodiment thus configured is explained in detail with reference to  FIGS. 10 and 11 . 
     Image Reading Process 
     Details of the image reading process will be explained with reference to  FIG. 10 . 
     As shown in  FIG. 10 , when the image photographing unit  116  (camera) rotatably placed in the notebook information processor  100  is rotated in the photographing direction of the plane (document plane) of the keyboard  112 , the rotation angle sensor  118  detects the rotation of the image photographing unit  116 . The control unit  102  automatically launches the scanning application and displays the same on the display  114  (monitor) to shift to the scanner mode to photograph the plane (document plane) of the keyboard  112  (Step SB- 1 ). 
     By the process by the live view displaying unit  102   a , the motion image photographed by the image photographing unit  116  is displayed on the display  114  (display) as the live view in real time. That is to say, the live view displaying unit  102   a  displays the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area of the image photographing unit  116  on the display  114 . The user adjusts the angle of the image photographing unit  116  while looking at the live view displayed on the display  114  (Step SB- 2 ). The live view displaying unit  102   a  may obtain the live view obtained by photographing at least a portion of the keyboard  112  within the photographing area of the image photographing unit  116 , and perform the projective transformation on the obtained live view so as to obtain the live view photographed from the front direction, thereby displaying the live view after the projective transformation to be explained later on the display  114 . 
     The rotation angle adjusting unit  102   f  may adjust the rotation angle γ of the motor  122  so as to adjust the photographing direction of the image photographing unit  116  based on the open angle θ detected by the open angle sensor  120 . 
     The photographing start signal generating unit  102   d  obtains the first image in which the document is not on the keyboard  112  and the second image in which the document is on the keyboard  112  as compared images, determines presence of the document, and generates the photographing start signal when there is the document to transmit the signal to the still image obtaining unit  102   b  (Step SB- 3 ). Photographing start signal generation by the photographing start signal generating unit  102   d  is explained in detail below. 
     The still image obtaining unit  102   b  obtains the image of the document by obtaining the still image from the live view displayed on the display  114 , when receiving the photographing start signal to start photographing the still image of the document put on the keyboard  112  from the photographing start signal generating unit  102   d  (Step SB- 4 ). 
     The brightness adjusting unit  102   e  may adjust the brightness of the display  114  when obtaining the still image by the still image obtaining unit  102   b.    
     The image processing unit  102   c  performs the projective transformation on the still image obtained by the processing by the still image obtaining unit  102   b  so as to obtain the image photographed from the front direction, and executes the image processing so as to perform the cropping to clip the document (Step SB- 5 ). The image processing unit  102   c  displays the transformed image of the document after the image processing on the display  114  and stores the same in the image database  106   a  (Step SB- 6 ). When displaying the live view after the projective transformation on the display  114  at Step SB- 2 , the image processing unit  102   c  may execute the image processing on the still image obtained by the processing by the still image obtaining unit  102   b  so as to perform the cropping to clip the document, and store the transformed image of the document after the image processing in the image database  106   a.    
     The image processing unit  102   c  may detect the corner of the document to perform cropping by comparing the first image in which the document is not on the keyboard  112  and the second image in which the document is on the keyboard  112  obtained by using the image photographing unit  116  by the process by the control unit  102  at Step SB- 4 . 
     The control unit  102  determines whether to finish the image reading process by determining whether a next document is set on the keyboard  112  (Step SB- 7 ). When the control unit  102  determines not to finish the image reading process (NO at Step SB- 7 ), the process returns to Step SB- 4  to continue the image reading process with the next document. On the other hand, when the control unit  102  determines to finish the image reading process (YES at Step SB- 7 ), the image reading process is finished. 
     Photographing Start Signal Generating Process 
     Details of the photographing start signal generating process will be explained with reference to  FIG. 11 . 
     The photographing start signal generating unit  102   d  obtains in advance the image (first image) of the keyboard  112  before setting the document on the keyboard  112  by photographing using the image photographing unit  116  (Step SC- 1 ). 
     The photographing start signal generating unit  102   d  initializes a counter B to “0” (Step SC- 2 ). 
     The photographing start signal generating unit  102   d  obtains the image (second image) including the document set on the keyboard  112  by photographing using the image photographing unit  116  (Step SC- 3 ). 
     The photographing start signal generating unit  102   d  continuously monitors the brightness information or the like of the photographed motion image input by means of the image photographing unit  116  (camera) and determines whether the difference in brightness value or the like between the image (first image) of the keyboard  112  obtained in advance and the image (second image) including the document set on the keyboard  112  reaches a certain level (Σ(brightness value of the first image−brightness value of the second image)&gt;threshold A?) by the process by the control unit  102 , thereby determining whether the document such as the document is started to be set on the keyboard  112 . (Step SC- 4 ). When it is determined that the difference is equal to or smaller than the threshold A and that the document such as the document is not set on the keyboard  112  (NO at Step SC- 4 ), the photographing start signal generating unit  102   d  returns to the process at Step SC- 2 . On the other hand, when it is determined that the difference is larger than the threshold A and that the document such as the document is started to be set on the keyboard  112  (YES at Step SC- 4 ), the photographing start signal generating unit  102   d  proceeds to a process at next Step SC- 5 . 
     The photographing start signal generating unit  102   d  counts the counter B to “1” (Step SC- 5 ). 
     The photographing start signal generating unit  102   d  determines whether variation in the difference is stable at a certain level (Σ(brightness value of the second image−brightness value of the previous second image)&lt;threshold C?), thereby determining whether the setting of the document is finished (Step SC- 6 ). When it is determined that the difference is equal to or larger than the threshold C and the variation in the difference is not stable at the certain level (NO at Step SC- 6 ), the photographing start signal generating unit  102   d  returns to the process at Step SC- 2 . On the other hand, the photographing start signal generating unit  102   d  proceeds to a process at next Step SC- 7  when it is determined that the difference is equal to or smaller than the threshold C and the variation in the difference is stable at the certain level (YES at Step SC- 6 ). 
     The photographing start signal generating unit  102   d  determines whether a predetermined time period has passed (counter B&gt;threshold D?) (Step SC- 7 ) When it is determined that the counter B is equal to or smaller than the threshold value and the predetermined time period has not passed (NO at Step SC- 7 ), the photographing start signal generating unit  102   d  returns to the process at Step SC- 3 . On the other hand, when it is determined that the counter B is larger than the threshold value and that the predetermined time period has passed (YES at Step SC- 7 ), the photographing start signal generating unit  102   d  proceeds to a process at next Step SC- 8 . 
     The photographing start signal generating unit  102   d  generates the photographing start signal (shutter trigger) to transmit the signal to the still image obtaining unit  102   b  (Step SC- 8 ). 
     The still image obtaining unit  102   b  obtains the still image from the live view displayed on the display  114  when receiving the photographing start signal to start photographing the still image of the document put on the keyboard  112  from the photographing start signal generating unit  102   d  (shutter trigger ON). The control unit  102  may inform the user of obtaining the vocal and the still image by means of an output unit (not shown) such as a speaker, or the display  114  (display), respectively, after the still image is obtained by the process by the still image obtaining unit  102   b . When the number of the documents to be scanned is large, a semi-automated operation becomes possible by repeating this. 
     Other Embodiments 
     The embodiments of the present invention are explained above. However, the present invention may be executed in not only the embodiments but also various different embodiments without departing from the spirit and scope of the general inventive concept as defined by the appended claims and their equivalents. 
     In the embodiment, the notebook information processor  100  that performs processing in a standalone mode is explained as an example. However, processing may be performed depending on a request from a client terminal constructed in a housing different from the housing of the notebook information processor  100 , and the processing result may be returned to the client terminal. 
     All the automatic processes explained in the present embodiment can be, entirely or in part, carried out manually. Similarly, all the manual processes explained in the present embodiment can be, entirely or in part, carried out automatically by a known method. 
     The process procedures, the control procedures, specific names, information including registration data of each process and parameters of search condition etc., display example, database structure mentioned in the description and drawings can be changed as required unless otherwise specified. 
     The constituent elements of the notebook information processor  100  are merely conceptual and may not necessarily physically resemble the structures shown in the drawings. For instance, the apparatus need not necessarily have the structure that is illustrated. 
     For example, the process functions performed by the notebook information processor  100 , especially regarding each of the process functions executed at the control unit  102 , can be entirely or partially realized by a central processing unit (CPU) or a computer program executed by the CPU or by a hardware using wired logic. The computer program, recorded on a recording medium, can be mechanically read by the i notebook information processor  100  as the situation demands. In other words, the computer program recorded on the recording medium can cause the storage unit  106  such as read-only memory (ROM) or hard disk (HD) to work in coordination with OS to issue commands to the CPU and cause the CPU to perform various processes. The computer program is first loaded to the random access memory (RAM), and forms a control unit  102  in collaboration with the CPU. 
     Alternatively, the computer program can be stored in any application program server connected to the notebook information processor s  100  via the network  300 , and can be fully or partially loaded as the situation demands. 
     “Computer-readable recording medium” on which the computer program can be stored may be a portable type such as flexible disk, magneto optic (MO) disk, ROM, erasable programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), compact disk-read-only memory (CD-ROM), digital versatile disk (DVD), or a communication medium that stores the computer program for a short term such as communication channels or carrier waves that transmit the computer program over networks  300  such as local area network (LAN), wide area network (WAN), and the Internet. 
     “Computer program” refers to a data processing method written in any computer language and can have software codes and binary codes in any format. The computer program can be a dispersed form in the form of a plurality of modules or libraries, or can perform various functions in collaboration with a different program such as the OS. Any known configuration in the image-reading processing apparatus according to the embodiment can be used for reading the recording medium. Similarly, any known process procedure for reading or installing the computer program can be used. 
     The storage unit  106  (such as image database  106   a ) is a fixed disk device such as RAM, ROM, and HD or flexible disk, optical disk, and stores therein various programs, tables, databases required for various processes and opening websites. 
     The notebook information processor  100  can also be connected to any existing personal computer, workstation, etc. and can be operated by executing software (that includes computer program, data, etc.) that implements the method according to the present invention in the personal computer or workstation. 
     Moreover, a specific manner of distribution, and integration of the apparatus is not limited to the example as described in the drawing. A part or all of the apparatus can be distributed or integrated functionally or physically in an arbitrary unit depending on various additions. 
     According to the present invention, since the document such as the paper document is put on the keyboard, the area equal to or larger than the notebook information processor is not required as the installation area of the document to be photographed, and it is possible to check in real time before capturing the image so as to adjust the photographing area. In addition, the image processing may be performed to the captured image in real time so as to obtain the image of the document photographed from the front direction and clipped from the background. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved with the minimum device weight and installation area. 
     According to the present invention, it is possible to determine presence of the document, thereby obtaining the photographing start signal as the trigger timing to obtain the still image. Especially, when the number of documents is large, it is possible to semi-automatically obtain the still image by repeating this. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     According to the present invention, it is possible to temporally change the brightness of the display when photographing the document and use the brightness of the display as the auxiliary light source. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     According to the present invention, it is possible to correctly and rapidly detect the corner of the borderline of the document, which is important in the cropping process. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     According to the present invention, for example, this may be formed as the existing notebook information processor or the like to which the existing digital camera or the like is USB connected, and be easily added or placed on the monitor or the like. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved with the minimum device weight and installation area. 
     According to the present invention, the photographing direction of the image photographing unit may be appropriately changed as needed. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     According to the present invention, it is possible to automatically detect that the photographing direction of the image photographing unit is changed from the initial position at which this acts as the WEB camera to photograph the user or the like. When detecting the change to the photographing direction, this may perform the automatic process so as to automatically launch the scanning software to shift to the scanner mode. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     According to the present invention, it is possible to automatically adjust the photographing direction of the image photographing unit so as to be able to photograph the document put on the keyboard according to the opening degree of the notebook information processor, which the user opens. Thereby, there is the effect to achieve the scanner function of which efficiency and accuracy when capturing the image are improved. 
     Although the invention has been described with respect to specific embodiments for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.