Patent Publication Number: US-2011075012-A1

Title: Photographing apparatus and control method thereof

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention is related to photographing apparatuses. In particular, the present invention relates to methods for controlling a photographing apparatus to perform photographing procedures automatically. 
     2. Description of the Prior Art 
     In recent years, with the flourishing development of electronic and optical techniques, digital photographing apparatuses have become very popular and widely used. Not only digital cameras but also lots of portable electronic products, for example, mobile phones or PDAs, are capable of taking photographs. Most digital photographing apparatuses have display panels. When the user is taking photo, the display panel can show preview images in real time. When the user wants to adjust the settings of the photographing apparatus, the display panel can show function lists. 
     There is a growing trend towards light and handy consumer electronics. Display panels with the function of touch control are thin and provide friendly user interfaces. Further, replacing traditional keyboards or buttons by touch screens can solve many problems in human-machine interfaces. Since techniques about touch screens have become mature and the cost of touch screens has become much lower than before, more and more digital photographing apparatuses are equipped with touch screens and provide functions related to users&#39; touch action. 
     Please refer to  FIG. 1 , which shows the outward appearance of a photographing apparatus. In this example, besides optical devices such as lenses (not shown), the photographing apparatus  10  includes a touch screen  12  and a button  14 . The technique of letting the user assign a focus point via the touch screen  12  has existed. More specifically, in the photographing mode, the user can move the focus frame  12 A shown on the touch screen  12  by touching the touch screen  12 . Once the location of the focus frame  12 A is confirmed and the button  14  is pressed thereafter, the control circuit in the photographing apparatus  10  will perform focusing and photographing procedures according to the focus point determined by the user. 
     The aforementioned control process has brought much convenience to the user. However, whenever the user presses the button  14 , his/her action inevitably induces unintentional shakes of the photographing apparatus  10 . The focus point might accordingly be shifted and even the taken photos might be blurred. 
     SUMMARY OF THE INVENTION 
     To solve the aforementioned problems, the invention provides methods for controlling a photographing apparatus to automatically perform a photographing procedure. The methods according to the invention can be applied in various photographing apparatuses including touch screens, for instance, digital cameras, mobile phones having the photographing function, or PDAs capable of taking photos. 
     In a control method in one embodiment according to the invention, it is first detected whether a user keeps touching a focus point on the touch screen for a specific duration. If the detected result is YES, the photographing apparatus is controlled to perform an automatic focusing procedure corresponding to the focus point and then an automatic photographing procedure. 
     Another embodiment according to the invention is also a method for controlling a photographing apparatus. In this method, it is first detected whether a user keeps touching a focus point on the touch screen for a specific duration. If the detected result is YES, the photographing apparatus is controlled to perform an automatic focusing procedure corresponding to the focus point. Subsequently, if the user touches a first area on the touch screen, the photographing apparatus is controlled to perform an automatic photographing procedure. On the contrary, if the does not touch the first area after the automatic focusing procedure, the photographing apparatus will not be controlled to perform the automatic photographing procedure. 
     In the embodiments according to the invention, after a user selects a focus point, he or she does not have to press any button and the photographing apparatus will optionally perform an automatic photographing procedure. Hence, the photographing apparatuses and control methods according to the invention can prevent problems induced by unintentionally shakes. More humanized operation processes and better photo qualities can also be provided. 
     The advantage and spirit of the invention may be understood by the following recitations together with the appended drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE APPENDED DRAWINGS 
         FIG. 1  shows a photographing apparatus. 
         FIG. 2(A)  and  FIG. 2(B)  show the flowchart of the control method in one embodiment according to the invention. 
         FIG. 3(A)  and  FIG. 3(B)  respectively illustrate the touch screen with and without showing touch keys. 
         FIG. 4(A)  shows an exemplary touch screen divided into three areas;  FIG. 4(B)  shows an exemplary ratio of the first area and the second area. 
         FIG. 5(A)  and  FIG. 5(B)  illustrate the flowcharts of the control method in another embodiment according to the invention. 
         FIG. 6(A)  and  FIG. 6(B)  illustrate exemplary block diagrams of the photographing apparatus according to the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     According to the invention, the photographing apparatus  10  shown in  FIG. 1  can have two different photographing modes. In the first mode, the photographing procedure is triggered if the button  14  is pressed. In the second mode, a user can trigger the photographing procedure directly via the touch screen  12 . The control methods for aforementioned the second mode according to the invention are explained in the following embodiments. 
     Please refer to  FIG. 2(A) , which shows the flowchart of the control method in one embodiment according to the invention. In this embodiment, step S 201  is first performed to detect whether a user keeps touching a focus point on the touch screen  12  for a specific duration. For example, if the specific duration is set as three seconds and a focus frame  12 A is touched, step S 201  is detecting whether the user keeps touching the focus frame  12 A for three seconds. 
     In actual applications, the focus frame  12 A is movable. The user can first move the focus frame  12 A to an expected focus point (e.g. a human face in the preview image) and then keeps touching the focus frame  12 A. In this embodiment, keeping touching the focus frame  12 A for the specific duration indicates that the user requests the photographing apparatus  10  to perform a focusing procedure corresponding to the focus frame  12 A and then a photographing procedure. 
     Therefore, if the detected result of step S 201  is YES, step S 202  is performed. In this step, the photographing apparatus  10  is controlled to perform an automatic focusing procedure corresponding to the location currently indicated by the focus frame  12 A. Practically, this automatic focusing procedure can be performed by adjusting the focal length of optical lenses and/or the size of images captured by an digital image processing device (not shown) in the photographing apparatus  10 . Since both optical focusing and digital focusing are techniques well known in this art, the detail of the focusing procedure will not be further described. 
     After step S 202 , step S 203  is executed for controlling the photographing apparatus  10  to perform an automatic photographing procedure. The scenery in front of the photographing apparatus  10  at this time is photographed. On the contrary, if the detected result of step S 201  is NO, step S 201  will be re-performed. 
     As shown in  FIG. 2(A) , in this embodiment, as long as the user keeps touching the focus frame  12 A after selecting a focus point, the photographing apparatus  10  will perform an automatic photographing procedure. Compared with pressing the button  14 , touching the focus frame  12 A induces less shakes for the photographing apparatus  10 . After selecting an expected focus point, the user even does not have to add extra power to press the focus frame  12 A. Accordingly, the aforementioned control method can prevent the problems induced by pressing the button  14 . 
     As shown in  FIG. 2(B) , further steps S 204 ˜S 207  can be included between steps S 202  and  5203 . The main purpose of step S 204  is judging whether the automatic focusing procedure in step S 202  is successive. If the judging result of step S 204  is YES, step S 205  will be performed so as to control the photographing apparatus  10  to convey a successive focusing message. On the contrary, if the judging result of step S 204  is NO, step S 206  will be performed so as to control the photographing apparatus  10  to convey a failed focusing message. With the messages, the user can know whether the automatic focusing procedure is successive. 
     For example, controlling the color of the focus frame  12 A to be turned into green can represent the focusing procedure is successive; controlling the color of the focus frame  12 A to be turned into red can represent the focusing procedure is failed. The messages can also be shown on the touch screen  12  as texts or be conveyed as voices via the speaker (not shown) disposed in the photographing apparatus  10 . 
     In this embodiment, no matter the automatic focusing procedure is successive or not, steps S 207  and S 203  will be subsequently performed. In step S 207 , an automatic exposure procedure and an automatic white-balancing procedure are performed, so as to further adjust the brightness and color of captured images. 
     In actual applications, when the photographing apparatus  10  is performing the automatic focusing procedure or the automatic photographing procedure, the function of detecting user actions by the touch screen  12  (e.g. step S 201 ) can be paused. After the detecting function is paused, there will not continuously be new detected results that might interfere the operations in the photographing apparatus  10 . 
     Please refer to  FIG. 3(A)  and  FIG. 3(B) . As shown in  FIG. 3(A) , according to the invention, the touch screen  12  can be divided into two (up-down or right-left) regions. In this example, the area above the dividing line  16  (hereinafter referred as the first area) is used for displaying preview images. The area below the dividing line  16  (hereinafter referred as the second area) is used for displaying one or more touch keys  18  (e.g. keys for zooming in, zooming out, switching modes, or showing an index). 
     Practically, starting to touch the first area that includes the focus frame  12 A generally indicates that the user desires to adjust the position of the focus frame  12 A. To provide larger or clearer preview images, when the user is touching the first area, the touch keys  18  in the second area can be hidden as shown in  FIG. 3(B) . Correspondingly, the functions of the touch keys  18  can be paused. If the user stops touching the touch screen  12 , the functions of the touch keys  18  can be recovered and the touch screen  12  can be recovered as shown in  FIG. 3(A) . 
     Please refer to  FIG. 4(A) . In another embodiment according to the invention, the touch screen  12  is divided into three areas: a first area  20 A approximately including the center region of the touch screen  12 , a second area  20 B that surrounds the first area  20 A, and a third area  20 C at the lower right corner of the touch screen  12 . As shown in  FIG. 4(A) , the focus frame  12 A is inside the first area  20 A.  FIG. 4(B)  shows an exemplary ratio of the first area  20 A and the second area  20 B. 
     One embodiment according to the invention is a control method for the touch screen  12  shown in  FIG. 4(A) .  FIG. 5(A)  illustrates the flowchart of this control method. In step S 501 , it is detected that whether a user keeps touching a focus point on the touch screen  12  for a specific duration. If the detected result of step S 501  is YES, step S 502  is executed to control the photographing apparatus  10  to perform an automatic focusing procedure corresponding to the focus point. If the detected result of step S 501  is NO, step S 501  is re-performed. 
     After step S 502 , step S 503  will be performed to judge whether the user is touching the first area  20 A. If the judged result of step S 503  is YES, step S 504  will then be performed to control the photographing apparatus  10  to perform an automatic photographing procedure. On the contrary, if the judged result of step S 503  is NO, as shown in step S 505 , the photographing apparatus  10  will not be controlled to perform the photographing procedure. 
     The main difference between the methods shown in  FIG. 5(A)  and  FIG. 2(A)  is that in the method shown in  FIG. 5(A) , the photographing apparatus  10  will not necessarily perform the automatic photographing procedure after the automatic focusing procedure is completed. More specifically, as long as the user does not touch the first area  20 A anymore after selecting a focus point, the succeeding photographing procedure will be abandoned. 
     Please refer to  FIG. 5(B) , which illustrates a more detailed control method according to the invention. The steps S 511 ˜S 512  in  FIG. 5(B)  are the same as the steps S 501 ˜S 502  in  FIG. 5(A) . The purpose of step S 513  is judging whether the automatic focusing procedure in step S 512  is successive. If the judging result of step S 513  is YES, step S 514  will be performed so as to control the photographing apparatus  10  to convey a successive focusing message. On the contrary, if the judging result of step S 513  is NO, step S 515  will be performed so as to control the photographing apparatus  10  to convey a failed focusing message. 
     According to the messages conveyed by the photographing apparatus  10 , the user can decide whether the succeeding photographing procedure will be performed or not. For instance, if finding out that the focusing procedure is failed and wanting to re-select another focus point, the user can remove his/her finger and stop touching the first area  20 A. 
     In this embodiment, after step S 514  or step S 515 , step S 516  can be performed to judge which area on the touch screen  12  is being touched by the user. If the user keeps touches the first area  20 A after the automatic focusing procedure, step S 517  is executed to control the photographing apparatus  10  to further perform an automatic photographing procedure. If the judging result of step S 516  indicates that the user has moved his/her finger to the second area  20 B or does not touch any part of the touch screen  12 , step S 511  is re-performed. 
     In the judging result of step S 516  indicates that the user has moved his/her finger to the third area  20 C, step S 518  will be executed to control the touch screen to show a function list, for example, including the touch keys  18  shown in  FIG. 3(A) . 
     Practically, the control methods shown in  FIG. 5(A)  and  FIG. 5(B)  can also include steps of automatic exposure procedure and automatic white-balancing procedure, so as to further adjust the brightness and color of captured images. Besides, when the photographing apparatus  10  controlled by the methods shown in  FIG. 5(A)  or  FIG. 5(B)  is performing the automatic focusing procedure or the automatic photographing procedure, the function of detecting user actions by the touch screen  12  can be paused. After the detecting function is paused, there will not continuously be new detected results that might interfere the operations in the photographing apparatus  10 . 
     Moreover, the control methods shown in  FIG. 5(A)  and  FIG. 5(B)  can also include the mechanism of showing/hiding the function list. For example, when the user is not touching the touch screen  12 , the touch screen  12  can display plural touch keys as shown in  FIG. 3(A) . Once the user starts to touch the area including the focus frame  12 A, most of the touch keys can be hidden as shown in  FIG. 4(A) . Only the touch key for starting the function list (i.e. the third area  20 C) is kept on the touch screen  12 . 
     Please refer to  FIG. 6(A) , which illustrates an exemplary block diagram of the photographing apparatus  10 . As shown in  FIG. 6(A) , the photographing apparatus  10  includes a photographing module  11 , a touch screen  12 , a microprocessor  13 , and an image processing module  15 . In actual applications, the photographing module  11  can include devices such as optical lenses and optical sensing plate. The touch screen  12  can include a touch panel of resistance-type, capacitance-type, optical-type, or ultrasonic-type. The image processing module  15  is used for performing procedures such as automatic exposure and automatic white-balancing. 
     The microprocessor  13  is used for overall planning and controlling the operations of the photographing module  11 , touch screen  12 , and image processing module  15 . In other words, the microprocessor  13  can be responsible for receiving the sensed results generated by the touch screen  12 . The microprocessor  13  can also control the photographing module  11  and the image processing module  15  based on the methods shown in  FIG. 2(A)  or  FIG. 5(A) . 
       FIG. 6(B)  illustrates another exemplary block diagram of the photographing apparatus  10 . The microprocessor  13  shown in  FIG. 6(B)  can also control the photographing module  11  and the image processing module  15  based on the methods shown in  FIG. 2(A)  or  FIG. 5(A) . In this example, the microprocessor  13  includes a detecting unit  13 A, a control unit  13 B, and a judging unit  13 C. The detecting unit  13 A is used for detecting whether a user keeps touching a focus point on the touch screen  12  for a specific duration. If the detected result of the detecting unit  13 A is YES, the control unit  13 B then controls the photographing module  11  to perform an automatic focusing procedure corresponding to the focus point. The judging unit  13 C is used for judging whether the user is touching the first area  20 A after the automatic focusing procedure is completed. If the judging result of the judging unit  13 C is YES, the control unit  13 B will control the photographing module  11  to perform an automatic photographing procedure. 
     As described above, in the embodiments according to the invention, after selecting a focus point, a user does not have to press any button and the photographing apparatus will optionally perform an automatic photographing procedure. Hence, the photographing apparatuses and control methods according to the invention can prevent problems induced by unintentionally shakes. Besides, more humanized operation processes and better photo qualities can also be provided. The aforementioned control methods can be applied not only in digital cameras but also photographing apparatuses including touch screens such as mobile phones having the photographing function, or PDAs capable of taking photos. 
     With the example and explanations above, the features and spirits of the invention will be hopefully well described. Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teaching of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims.