Patent Publication Number: US-2010124363-A1

Title: Display privacy system

Description:
TECHNICAL FIELD 
     The present invention generally relates to the field of electronic devices and, more particularly to a method and arrangement for controlling a display privacy filter for the electronic device. 
     BACKGROUND 
     Electronic devices having a display, such as personal computers (“PCs”), are becoming increasingly commonplace. Such electronic devices may be portable, for example, laptop computers, cordless and cellular telephones, personal digital assistants (PDAs), etc. Users of such portable electronic devices typically take these devices with them anywhere they go, which increases the risk of unintended divulgence of personal and/or confidential information to individuals other than the user who may view the display, e.g., passers-by who may glance at the display. 
     Display privacy filters are designed to aid users in protecting sensitive information by shielding the display screen view from anyone viewing the display from an angle, e.g., the side of the monitor, while allowing persons positioned directly in front of the display to view content being displayed. 
     Since many applications run on communication device are personal in nature, privacy filters are also becoming increasingly popular for mobile phones, for example, in Japan. A conventional solution involves attaching a miniature version of the filters used on laptops onto the phone display. However, conventional privacy filter solutions suffer from some major drawbacks, for example, the filters can adversely affect the color reproduction and also “steal” some light. This results in a corresponding requirement for increased backlighting in the display, which means higher power consumption and thus an adverse impact on battery performance. 
     A potential resolution of these issues may be to develop electronically controlled built-in privacy filters, which can be activated and deactivated by a user, for example, using a menu system of the device. It could then be possible for users to switch the filter on only on an as-needed basis, and thereby conserve color and battery performance. However, some users may be inclined to just leave the filter on, since manual user interaction would be necessary to activate/deactivate the filter, especially if the phone does not have a dedicated button for this purpose. In addition, some users may take a “better safe than sorry” approach to filter use, reasoning that it is preferable not to turn the filter off than to risk forgetting to turn it on later when discreet use of the device is desired. For example, the user may later be so engrossed on displayed confidential information on the monitor so as to be unaware that another person has approached the user, for example, from behind, who may surreptitiously peer at the sensitive information. Or, the user may be find himself in environment (e.g., seated on mass transit) in which the user is flanked by individuals who will necessarily be privy to what is displayed. In other circumstances, a user may using a gaming console and seated next to a competitor, for example, in a car, and unbeknownst to the user, the competitor may be able to view the user&#39;s gaming console, to the competitive disadvantage of the user. 
     Further, user-activated electronically-controlled privacy filter functionality adds complexity to the use of the device, presenting difficulties for the user in operating the device without consulting a manual. A possible solution may be to introduce a dedicated hardware button which could be used for manipulating the electronically controlled privacy filter. Such a solution may be somewhat easy to use for a user; however, additional production costs are involved. Furthermore, an extra dedicated button on a portable electronic device adds increased volume to the limited design space available in such devices. As a consequence, some or all other hardware buttons and/or the display have to be reduced in scale to accommodate a new dedicated input mechanism. 
     Thus, maintaining privacy by not compromising sensitive information when using an electronic device that includes a display presents a design challenge in manufacturing such devices. 
     In addition, as commercial competition increases among portable communication devices, marketing opportunities exist for increased functionality and enhanced user features. 
     SUMMARY 
     Embodiments of the present invention may resolve at least some of the above-mentioned issues and provide a superior user privacy feature with respect to displayed information. 
     A first embodiment of the present invention is directed to a method performed in an electronic device which controls a display privacy filter. The display privacy filter may be provided for a display of the electronic device. The electronic device may include an image capturing unit. The image capturing unit may be configured to capture an image of an object situated in view of the display. The method may include the step of capturing an image of the object. The method may include the step of detecting more than one human face present in the captured image. The method may include the step of activating the privacy filter on the display when more than one face is detected on the captured image. 
     A second embodiment of the present invention may include the features of the first embodiment, and the further step of deactivating the privacy filter on the display if only one face is detected on the captured image. 
     A third embodiment of the present invention may include the features of the first embodiment, and the further steps of comparing each detected human face against a list of approved user faces. The method may include the further step of recognizing if each compared human face belongs to a non-approved user and, if so, the method may include the further step of activating the privacy filter on the display. 
     A fourth embodiment of the present invention may include the features of the third embodiment, and the further step of deactivating the privacy filter on the display, if no non-approved human face is detected on the captured image. 
     A fifth embodiment of the present invention may include the features of the third embodiment, and the further step of deactivating the privacy filter on the display, if only approved human faces are detected on the captured image. 
     A sixth embodiment of the present invention may include the features of the first embodiment, and the further step of determining if the display privacy filter on the display is active or inactive. The method may include the further step of setting the image capturing interval to a first interval value if the display privacy filter is inactive and a second, different interval value if the display privacy filter is active. 
     A seventh embodiment of the present invention may include the features of the first embodiment, wherein the step of activating the privacy filter on the display is performed if the privacy filter is not already active. 
     An eighth embodiment of the present invention may be directed to an arrangement in an electronic device for controlling a display privacy filter. The display privacy filter may be provided on a display, which may be provided within the electronic device. The electronic device may include an image capturing unit that may be configured to capture an image of an object situated in view of the display. The arrangement may include a detection unit. The detection unit may be configured to detect the number of human faces on a captured image. The arrangement may include an activation unit that may be configured to activate the privacy filter on the display, if more than one face is detected on the captured image. 
     A ninth embodiment of the present invention may include the features of the eighth embodiment, wherein the electronic device is a portable electronic device represented by a mobile cellular radiotelephone. 
     A tenth embodiment of the present invention may be directed to a computer program product including computer-readable program code embodied on a computer-readable storage medium. The computer readable program code may be configured to perform the method steps according to any of the embodiments, for example, by executing a set of corresponding instructions. 
     Thanks to the present solution, images of the objects momentarily situated in front of the display are taken and analysed. If more than one human face, or any unknown human face is detected, an electronically controlled display privacy filter is activated. Thus the risk of forgetting to turn the privacy filter is reduced, not to say eliminated, which improves the security and provide an improved privacy mechanism. 
     Embodiments of the present method, arrangement, and computer program may advantageously provide a privacy filter that may be turned on/off as it is needed, without any interaction by the user. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will now be described more in detail in relation to the enclosed drawings, in which: 
         FIG. 1  is a schematic block diagram illustrating embodiments of an electronic device; 
         FIG. 2A  is a schematic block diagram illustrating embodiments of an electronic device; 
         FIG. 2B  is a schematic block diagram illustrating embodiments of an electronic device; 
         FIG. 3A  is a schematic block diagram illustrating exemplary components of an electronic device according to some embodiments; 
         FIG. 3B  is a schematic block diagram illustrating an electronic device according to some embodiments, where the electronic device is embodied as a cellular telephone; 
         FIG. 4  is a flow chart illustrating embodiments of method steps in an electronic device; and 
         FIG. 5  is a block diagram illustrating embodiments of an arrangement in an electronic device. 
     
    
    
     DETAILED DESCRIPTION 
     The invention is directed to a method, an arrangement, and a computer program executed in an electronic device, which may be implemented in a number of embodiments described below. This invention may, however, be embodied in many different forms and should not be considered as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. 
     Still other objects and features of the present invention will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. It should be further understood that the drawings are not necessarily drawn to scale and that, unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. 
       FIG. 1  is a schematic illustration of an embodiment of an electronic device  100  that may include a display  110  and a display privacy filter  115 . Electronic device  100  may include an image capturing unit  120 . A user  130  may view display  110 . When an unauthorized viewer  666  is in a position to espy display  110 , display privacy filter  115  may be activated, to thereby at least partially conceal the contents of images on display  110  from a perspective of unauthorized viewer  666 , for example, on a flank of user  130 . 
     Electronic device  100 , as described herein, may, according to some embodiments, include a personal computer (PC), a TV, a movie playback device, a film screen, a camera, an image displaying device, or any other electronic device having a display. Electronic device  100  may include, for example, a portable electronic device having a display, such as a mobile station, a mobile cellular radiotelephone, a digital enhanced cordless telecommunications (DECT) telephone, a personal digital assistant (PDA), a laptop, a computer, a digital still camera, a digital video camera, or any other kind of electronic device having a display, such as a notebook computer, a walkie-talkie, a hunting radio, a baby monitor, a handheld gaming apparatus, a GPS receiver etc. 
     Display  110  may sometimes also be referred to as a monitor or a screen. Display  110  may include a piece of electrical equipment which is configured to display the visual representation, e.g., transient images, generated from the video output of electronic device  100 . Display  110  may include, for example, liquid crystal display (LCD), a thin film transistor (TFT) LCD, a cathode ray tube (CRT), a raster scan computer monitor, a vector display, a plasma display panel (PDP), a surface-conduction electron-emitter display (SED), an organic light-emitting diode (OLED) display, a monochrome super video graphics array (SVGA), etc., just to mention some arbitrary and non-limiting examples. 
     Display privacy filter  115  may be electronically controlled, for example, activated and deactivated electronically. When display privacy filter  115  is active, it may operate to decrease the viewing angle of display  110 , preventing it from being viewed, for example, from acute angles, such as from one or both sides. User  130  of electronic device  100  may view the display, but the view of unauthorized viewer  666 , trying to sneak a glimpse of display  110  from the side, may be partially, substantially, or totally obscured or otherwise distorted. For example, viewing perspectives that deviate from a geometric normal of display  110  may be made progressively worse. However, display privacy filter  115  may also filter out the glare generated from the glass surface of a CRT display as well as the radiation emitted from CRT and LCD displays. 
     Image capturing unit  120  may reside within electronic device  100  and be configured to capture an image of subjects in front of display  110 , for example, in an area in which at least a portion of the graphic information rendered via display  110  may be at least partially visible. Image capturing unit  120  may be, for example, the front camera of a mobile telephone, which otherwise normally is used for video telephony and the like. Mentioned as some nonlimiting examples only, image capturing unit  120  may include a charge-coupled device (CCD) digital camera, an active-pixel sensor (APS), a complementary metal-oxide-semiconductor (CMOS) sensor, Three-CCD or 3CCD, or similar technologies. 
     Image capturing unit  120  may, according to some embodiments, have a variable frame rate speed. Thus, image capturing unit  120  may capture an image, for example, once every few seconds when display privacy filter  115  is inactive and, for example, once every tenth of a second when display privacy filter  115  is active, according to some embodiments. Other regular or irregular, predetermined or random, time intervals are possible. 
     The images captured by image capturing unit  120  may be sent to a detection unit, which may be configured to apply a face detection algorithm in order to determine the number of human faces (e.g., those of user  130  and unauthorized viewer  666 ) present in the captured image. When more than one human face is detected, an electronic signal may sent to electronically controlled display privacy filter  115  in order to activate privacy filter  115 , according to some embodiments. The detection unit may reside, for example, within image capturing unit  120  or within electronic device  100 . However, the detection unit may, according to some embodiments, even be external to electronic device  100 . In such embodiments, electronic device  100  and the detection unit may be connected (e.g., wired or wirelessly), and the digital images distributed to the detection unit via the connection. 
     Face detection is a computer technology that determines the locations and sizes of human faces in digital images. It detects facial features and disregard other objects, such as animals, buildings, trees, and bodies. The face detection algorithm may be configured to detect frontal human faces and/or multi-view face detection. That is, the detection of faces that are either rotated along the axis from the face to the observer (e.g., profile), or rotated along the vertical or left-right axis, or both. 
     Some examples of known face detection algorithms that may be used according to the present solution may include, for example, Viola &amp; Jones, Schneiderman &amp; Kanade, or Rowley, Baluja &amp; Kanade: Neural Network-based Face Detection, just to briefly mention some few examples of such algorithms. Other face recognition techniques, crude or sophisticated, may be used. 
       FIGS. 2A and 2B  illustrate an embodiment of electronic device  100  including display  110  having display privacy filter  115 . User  130  of electronic device  100  may desire and/or be indifferent to share his/her visual experience of display  110  with, for example, a second, appoved viewer  140 , but still not want to expose the display to unauthorized viewer  666 . According to some alternative embodiments of the present invention, the detection unit may include a face recognition arrangement, for example, a face recognition component. The face recognition algorithm may recognize, identify, and/or verify a particular face represented in a digital image and/or a video frame from a video source. According to some embodiments, face recognition may be performed by comparing select facial features from the image and a database of facial images. 
     Some facial recognition algorithms identify faces by extracting features from an image of the subject&#39;s face. For example, an algorithm may analyze the relative position, size, and/or shape of the eyes, nose, cheekbones, and jaw, etc. These features may then be used to search for stored images that are determined to have having matching features, for example, to a specified degree of likeness. Other algorithms may normalize a gallery of face images and then compress the face data, only saving the data in the image that is useful for face detection. A probe image may then be compared with the face data. 
     Some non-limiting examples of face recognition algorithms that may be used according to some embodiments comprise Eigenface, Fisherface, the Hidden Markov model, and the neuronal motivated dynamic link matching. Other crude or sophisticated face recognition techniques may be used. 
     A further check thus may be performed involving the activation of a face recognition algorithm, in order to verify if the detected human face(s) within the captured image is approved by user  130  in control of electronic device  100 . This may be performed by comparing the detected human faces against a database including the approved viewers specified by user  130 . According to some embodiments, a comparison against a list of images included in the user  130 &#39;s contact list may be performed. According to some embodiments, user  130  may establish a database including images of faces of those individuals on the approved viewer list. 
     According to the scenario depicted in  FIG. 2A , appoved viewer  140  may be included in user  130 &#39;s database of authorized viewers. Thus a plurality of viewers may be present in front of the display  110  (e.g., as detected in the captured image), without triggering display privacy filter  115 . 
     In the scenario depicted in  FIG. 2B , unauthorized viewer  666 , who is not included in user  130 &#39;s database of approved viewers, may again try to stealthily get a glimpse of display  110 . As the face of unauthorized viewer  666  is not recognized by the face recognition algorithm, a signal is sent to privacy filter  115  to cause privacy filter  115  to activate and thereby at least partially conceal the contents of display  110  from unauthorized viewer  666 . 
       FIG. 3A  illustrates electronic device  100  consistent with an exemplary embodiment. Electronic device  100  may include a transceiver  305 , a processing unit  310 , a memory  315 , an input device  320 , an output device  325 , and/or a bus  330 . However it is to be noted that electronic device  100  by no means is limited to communication devices or portable communication devices. 
     Optional transceiver  305  may include transceiver circuitry for transmitting and/or receiving symbol sequences using radio frequency signals via one or more antennas. Transceiver  305  may include, for example, a RAKE or a GRAKE receiver. 
     Processing unit  310  may include a central processing unit (CPU), processor, microprocessor, or processing logic that may interpret and execute instructions. Processing unit  310  may perform all data processing functions for inputting, outputting, and/or processing of data including data buffering and device control functions, such as call processing control, user interface control, or the like. 
     Memory  315  may provide permanent, semi-permanent, and/or temporary working storage of data and instructions for use by processing unit  310  in performing device processing functions. Memory  315  may include ROM, RAM, large-capacity storage devices, such as a magnetic and/or optical recording medium and its corresponding drive, and/or other types of memory devices. Input device  320  may include mechanisms for entry of data into electronic device  100 . The keypad may permit manual user entry of data into electronic device  100 . The microphone may include mechanisms for converting auditory input into electrical signals. Display  110  may provide a user interface, e.g., a graphical user interface, that can be used by user  130  for selecting device functions. Display  110  may include any type of visual display, such as, for example, an LCD, a plasma screen display, an LED display, a CRT display, an OLED display, etc. 
     The output device  325  may comprise mechanisms for outputting data in audio, video and/or hard copy format. For example, the output device  325  may comprise a speaker that comprises mechanisms for converting electrical signals into auditory output. Output device  325  may include display  110  that may display output data to user  130 . For example, display  110  may provide a GUI that displays output data to user  130 . Bus  330  may electrically interconnect the various components of electronic device  100  to permit the components to communicate with one another. 
     The configuration of components of electronic device  100  illustrated in  FIG. 3A  is for illustrative purposes only. Other configurations including more, fewer, and/or a different arrangement of components may be implemented. For example, in some implementations, electronic device  100  may not include transceiver  305 . 
       FIG. 3B  illustrates an exemplary implementation of electronic device  100  in which electronic device  100  is a cellular radiotelephone. As shown in  FIG. 3B , electronic device  100  may include, for example, a microphone  335 , e.g., of input device  320  for entering audio information into electronic device  100 , a speaker  340 , e.g., of output device  325  for providing an audio output from the radiotelephone, a keypad  345 , e.g., of input device  320  for manual entry of data or selection of telephone functions, and display  110  that may visually display data and/or images and/or which may provide a user interface that may be used to enter data or to select telephone functions, in conjunction with keypad  345 . 
       FIG. 4  is a flow chart illustrating a method that may be implemented in electronic device  100  for controlling display privacy filter  115 . Display privacy filter  115  may be provided for display  110  of electronic device  100 . Electronic device  100  may include image capturing unit  120 . Image capturing unit  120  may be configured to capture an image of an object within a predetermined line of sight of display  110 . Display  110  may be adapted to display visual data, such as film sequences, movies, images, graphics, maps, web pages, text, games, video telephony connections, etc. 
     To appropriately control display privacy filter  115 , the method may include a number of Steps  401 - 408 . It is however to be noted that some of the described method steps are optional and only to be performed in some embodiments. Further, it is to be noted that the method Steps  401 - 408  may be performed in any arbitrary chronological order and that some of them, e.g., Step  401  and Step  403 , or even all steps may be performed simultaneously and/or in an altered, arbitrarily rearranged, decomposed or even completely reversed chronological order. The method may comprise the following exemplary steps: 
     Step  401   
     Step  401  may be performed in some embodiments, in which a determination may be made whether display privacy filter  115  on display  110  is active/inactive. The mode of display privacy filter  115  may determine the achievements of the present method. Thus, when display privacy filter  115  is inactive, the present method may determine whether the preset conditions for activating display privacy filter  115  exist, and vice versa. 
     Step  402   
     Step  402  may be performed in some embodiments, in which the image capturing interval may be set to a first interval value when display privacy filter  115  is inactive, and a second interval value when display privacy filter  115  is active. The first interval value may be different from the second interval value, according to some embodiments. For example, when display privacy filter  115  is inactive, a more frequent interval of capturing images may be used than when the display privacy filter  115  is active. According to some embodiments, the first interval value may be set, for example, to capturing one image every few seconds or so, such as one image about every 1-3 seconds or so. Other intervals are possible. 
     When display privacy filter  115  is active, the image capturing interval may be reduced, for example, in order to save energy. Also, it may be disturbing for user  130  when display privacy filter  115  is frequently activated/deactivated in response to detection of transient passers-by that do not pose a credible threat of ogling. Such circumstances may warrant deactivation of display privacy filter  115 . According to some embodiments, the second interval value may be set to, for example, one image every tenth of a second, such as one image about every 10-15 seconds. Other intervals are According to some embodiments, the second interval value may be set based on, for example, the corresponding sensitivity of the content being displayed and/or the environment in which electronic device  100  is being used. 
     According to some embodiments, electronic device  100  may be configured to not activate display privacy filter  115  when more than one person&#39;s face is detected and/or when an authorized person&#39;s face is recognized in fewer than a predetermined number of captured images, for example, corresponding to a predetermined amount of time. In this manner, needless activation of display privacy filter  115  may be avoided for transient passers-by that would not have sufficient time to glean any of the displayed information. 
     According to still other embodiments, user  130  may be alerted to the fact that conditions warrant activation of display privacy filter  115  and be given the opportunity to select to not activate display privacy filter  115  during a predetermined deferral period (e.g., 5, 10, 15 secs., etc.), after which, display privacy filter  115  will be activated, absent intervention by user  130 . 
     Step  403   
     In Step  403 , an image may be captured by image capturing unit  120 . According to some embodiments, image capturing unit  120  may be configured to continuously capture images of the objects situated in front of display  110 , as long as display  110  and/or some particular functionality, such as video display related to, for example, pornographic material or a gaming application, is turned on. 
     Electronic device  100  may activate the image capturing function in image capturing unit  120 , for example, camera functionality, upon powering up of electronic device  100 , according to some embodiments. The activation of image capturing function may also be accomplished manually by user  130 . 
     Step  404   
     In Step  404 , the number of human faces present on the captured image may be detected. The detection may be made by computation, using a face detection algorithm. 
     Step  405   
     Step  405  may be performed in some embodiments, in which the detected human faces in the image may be compared against representations associated with faces corresponding to a list and/or a particular sub-list of approved viewers. The list may be stored in a database associated with electronic device  100 . 
     According to some embodiments, the detected human faces in the image may be compared against a list and/or a particular sub-list of non-approved users. Such circumstances may obtain, for example, in an office setting in which an employee prefers that information not be viewed by a superior (e.g., user  130 &#39;s supervisor), but does not mind sharing the display content with other employees such as user  130 &#39;s colleagues. 
     In some embodiments, user  130  may designate unauthorized and/or approved viewer groups corresponding to particular viewers. In still other embodiments, user  130  may designate unauthorized and/or approved viewer groups corresponding to categories of viewers based on, for example, select shared characteristics, such as ages, genders, etc. For example, a facial characteristic detection algorithm may determine whether a viewer is a male/female, a minor/adult, etc. Thus, user  130  may configure display privacy filter  115  to be activated when a visage of that of a female or a minor is detected in the captured image, when user  130  is viewing, for example, pornographic material via display  110 . In another example, electronic device  100  may be configured to determine whether the image content being displayed via display  110  is suitable for minors (e.g., pornographic), and automatically activate display privacy filter  115  when a visage of that of a minor is detected in the captured image. 
     Step  406   
     Step  406  may only be performed in some embodiments, in which a determination is made as to whether any of the detected human faces belongs to an unauthorized viewer  666 . 
     Step  407   
     In Step  407 , when more than one face is detected on the captured image, privacy filter  115  may be activated with respect to display  110 . According to some embodiments, privacy filter  115  may be activated when it has been determined that any of the detected human faces likely belongs to unauthorized viewer  666 . The activation may be performed by sending an electronic signal to electronically controlled display privacy filter  115 . 
     According to some embodiments, privacy filter  115  associated with display  110  may be activated only when privacy filter  115  is not currently active. 
     Step  408   
     In Step  408 , privacy filter  115  for display  110  may be deactivated, when only one face is detected on the captured image. 
     According to some embodiments, privacy filter  115  may only be activated on display  110  when no unauthorized human face is detected in the captured image. 
     According to some embodiments, privacy filter  115  of display  110  may be deactivated when only approved faces are detected on the captured image. 
     According to some embodiments, privacy filter  115  for display  110  may be deactivated only when privacy filter  115  is active. 
     According to still other embodiments, privacy filter  115  may be applied to select areas of display  110  based on a detected position of unauthorized viewer  666 . For example, unauthorized viewer may be determined to be to one side of display  110 . In this circumstance, privacy filter  115  may be unilaterally applied to display  110  such that contents of images being rendered via display may not be readily viewed from unauthorized viewer  666 &#39;s vantage point, but may, however, still be discernible from an opposite side of user  130 , for example, from a vantage point of approved viewer  140 . 
     According to still other embodiments, upon detecting unauthorized viewer  666  in the captured image, electronic device  100  may include logic to generate a graphic and/or audible signal that indicates that unauthorized viewer  666  is able to view display  100  and may alert user  130  and/or unauthorized viewer  666  to that fact. In the latter case, electronic device  100  may be configured to generate an audible and/or visual request for privacy that may be presented to unauthorized viewer  666 . Electronic device  100  may be configured to progress through a number of such messages when a determination is made that unauthorized viewer  666 &#39;s viewing persists in spite of the presented request(s). 
       FIG. 5  is a block diagram illustrating embodiments of an arrangement  500  that may be provided in electronic device  100 . Electronic device  100  may be a portable electronic device represented by, for example, a mobile cellular radiotelephone, according to some embodiments. 
     Arrangement  500  may be configured to perform Steps  401 - 408  for controlling display privacy filter  115  with respect to display  110 . Display  110  may be associated with electronic device  100 . Electronic device  100  may include image capturing unit  120 . Image capturing unit  120  may be configured to capture an image of an object situated in front of display  110 . 
     For the sake of clarity, any internal electronics of arrangement  500 , not completely necessary for explaining the present method has been omitted from  FIG. 5 . 
     Arrangement  500  may include a detection unit  504 . Detection unit  504  may be configured to detect a number of human faces on a captured image is greater than one. Arrangement  500  may include an activation unit  507 . Activation unit  507  may be configured to activate privacy filter  115  via display  110 , for example, when a determination is made that more than one face is detected on the captured image. 
     Arrangement  500  may include a determination unit  501  that may be configured to determine if display privacy filter  115  on the display  110  is active/inactive. 
     Arrangement  500  may include a setting unit  502  that may be configured to set the image capturing interval to a first interval value when display privacy filter  115  is inactive and a second interval value when display privacy filter  115  is active. 
     Arrangement  500  may include a comparison unit  505  that may be configured to compare the detected human faces in a captured image to those included in a list of approved user faces. 
     Arrangement  500  may include a recognition unit  506  that may be configured to recognize and determine if any of the detected human faces substantially resembles that of a non-approved viewer. 
     In addition, Arrangement  500  further may include a deactivating unit  508  that may be configured to deactivate privacy filter  115  on display  110 , when only one face is detected based on results of an analysis of the captured image. Deactivating unit  508  may alternatively be configured to deactivate privacy filter  115  on the display  110 , when only approved human faces are detected from an analysis of the captured image. According to some embodiments, deactivating unit  508  may be configured to deactivate privacy filter  115  on the display  110 , only when no non-approved human face are detected based on an analysis of the captured image. 
     Arrangement  500  may, according to some embodiments, include processing unit  310 . Processing unit  310  may include a CPU, a processor, a microprocessor, and/or processing logic that may interpret and execute instructions. Processing unit  310  may perform all or some data processing functions for inputting, outputting, and/or processing of data including data buffering and device control functions, such as call processing control, user interface control, or the like. 
     It is to be noted that described units  110 - 508  included within arrangement  500  may be regarded as separate logical entities but not with necessity as separate physical entities. Any, some, or all of units  110 - 508  may be integrated or co-arranged within the same physical unit. However, in order to facilitate the understanding of the functionality of arrangement  500 , units  110 - 508  are illustrated as separate physical units in  FIG. 5 . 
     The method in electronic device  100  for controlling display privacy filter  115 , according to the present method, may be implemented through one or more processors  310  in electronic device  100 , together with computer program code for performing the functions of the described method. The program code mentioned above may also be provided as a computer program product, for instance in the form of a data carrier carrying computer program code for performing the method according to the present invention when being loaded into processing unit  310 . The data carrier may be a CD ROM disc, a memory stick, or any other appropriate medium such as a disk or tape that can hold machine-readable data. The computer program code can furthermore be provided as pure program code on a server and downloaded to electronic device  100  remotely. 
     Thus a computer program including instruction sets for performing the method according to at least some of method steps  401 - 408  may be used for implementing any of the previously described methods or portions thereof. 
     Further, a computer program product comprising computer-readable program code embodied on a computer-readable medium, the computer readable program code being configured to perform the method steps defined in the independent method claim. 
     As will be appreciated by one of skill in the art, the present invention may be embodied as arrangement  500  within electronic device  100 , a method or a computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, a software embodiment, or an embodiment combining software and hardware aspects all generally referred to herein as a “circuit” or “module.” Furthermore, the present invention may take the form of a computer program product on a computer-usable storage medium having computer-usable program code embodied in the medium. Any suitable computer readable medium may be utilized including hard disks, CD-ROMs, optical storage devices, a transmission media such as those supporting the Internet or an intranet, or magnetic storage devices. 
     Computer program code for carrying out operations of the present invention may be written in any arbitrary object oriented programming language such as Java®, Smalltalk or C++. However, the computer program code for carrying out the steps of the present method may also be written in any conventional procedural programming languages, such as the “C” programming language and/or a lower level assembler language. The program code may execute entirely on arrangement  500 , partly on arrangement  500 , as a stand-alone software package, partly on arrangement  500  and partly on a remote computing device or entirely on the remote computing device. In the latter scenario, the remote computing device may be connected to arrangement  500  through a local area network (LAN) and/or a wide area network (WAN), or the connection may be made to an external computer, for example, through the Internet, using an Internet service provider (ISP). 
     Furthermore, the present method is described in part above with reference to flowchart illustrations of the method in  FIG. 4  and/or block diagrams of arrangement  500  in  FIG. 5  according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks, which may be performed in any successive order and/or parallel. 
     These computer program instructions may also be stored in a computer-readable memory storage device that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks in  FIGS. 4  and/or  5 . 
     The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. 
     The terminology used in the detailed description of the particular exemplary embodiments illustrated in the accompanying drawings is not intended to be limiting of the invention. 
     Like reference numbers signify like elements throughout the description of the figures. 
     As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless expressly stated otherwise. It should be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including” when used in this specification is taken to specify the presence of stated features, integers, steps, operations, elements, and/or components, but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. 
     Furthermore, “connected” or “coupled” as used herein may include wirelessly connected or coupled. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. 
     Unless otherwise defined, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which electronic device  100  and the present method belongs. It will further be understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.