Abstract:
A method for capturing an image using an image acquisition device, includes determining that at least one area of an image to be captured has been selected, analyzing geometrical and compositional properties of an area surrounding the at least one area, providing a dynamic compositional guideline based on a result of analyzing the geometrical and compositional properties, and indicating when the image to be captured should be captured based on a position of the dynamic compositional guideline relative to the image to be captured.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    Aspects of the present disclosure relate to an apparatus and method for capturing an image where at least one area of an image to be captured has been selected. 
         [0003]    2. Description of the Related Art 
         [0004]    The increasing availability of digital cameras has resulted in an increasing number of digital photographs being taken. Camera manufactures have invested enormous efforts in providing better algorithms for exposure control, color balance compensation, sharpening, color rendering, etc. but there has been little effort in aiding users to take pictures with better spatial composition. This has resulted in users ending up with many pictures that are not aesthetically pleasing to view. 
         [0005]    In some cases, photographs are viewed as a way for a photographer to convey a particular message, such as a statement, an impression, or an emotion. A good photographer is an author trying to convey the message in a clear, concise and effective way. Like any other message, the message being conveyed by the photographer through a particular photograph needs a main subject (people, animal, plant, building, natural vista, abstract form, etc. . . . ). In order to compose the message it is necessary to include a secondary message that provides context, such as the main subject&#39;s surrounding. By combining the subject and the context, a complete message can be created. 
         [0006]    In creating the complete message, it is just as important to know what to exclude as knowing what to include. Anything that is not part of the main subject or its associated context is typically only a distraction. In order to give a flavor and style to a particular photograph, the photographer has to consider structural composition by using elements in the scene such as lines, geometry, perspective, color, texture, etc. . . . . 
         [0007]    Currently, some commercially available digital cameras address this need by presenting guidelines to the user overlaid in the viewfinder or on the LCD display of the digital camera. The guidelines are horizontal and vertical and divide the image into thirds to aid the user in composing a picture according to the rule of thirds. One such camera allows the user to move the lines so they are aligned with objects in the image. Another camera includes diagonal lines that cross in the lower two thirds of the display and also includes a center square to help with proportions. 
         [0008]    Other commercially available digital cameras include an analysis function that analyzes an image in order to suggest compositional corrections to the user. One camera looks for people by analyzing for flesh tones and provides advice by displaying a text warning. Another camera encourages the user to consider the best use of the whole frame by analyzing proportions of the people or objects in relation to strong horizontal or vertical lines. It then provides arrows indicating the directions in which the camera should be moved in order to create a more proportional image. Still yet, another camera analyzes the image to determine general characteristics of the scene and then chooses an appropriate template to overlay on the image thus directing the user in regards to proportion and framing. 
         [0009]    After image capture, there are several post-processing tools available to the user that allows the user to alter the composition of the image. Post-processing tasks are typically time consuming and there are certain compositional elements that cannot be altered after the image is taken, such as shooting view point, wider angle shooting, or moving an element in the picture (by arranging elements in the scene). Standard commercially available post-processing applications typically just allow simple operations such as cropping and image rotation in 90-degree steps. An image that is well composed from the beginning will make much more efficient use of the image resolution and require far less post-processing to arrive at a pleasing image. 
         [0010]    In light of the above, what is needed are better tools to aid a user in composing aesthetically pleasing and compelling images at the time the images are captured. An image that is well composed from the time it is captured will require less post-processing time and enable a user to obtain an aesthetically pleasing result more efficiently. 
       SUMMARY OF THE INVENTION 
       [0011]    According to one aspect of the invention, a method for capturing an image using an image acquisition device, includes determining that at least one area of an image to be captured has been selected, analyzing geometrical and compositional properties of an area surrounding the at least one area, providing a dynamic compositional guideline based on a result of analyzing the geometrical and compositional properties, and indicating when the image to be captured should be captured based on a position of the dynamic compositional guideline relative to the image to be captured. 
         [0012]    Further features of the present disclosure will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  is a block diagram illustrating an imaging apparatus according to an exemplary embodiment. 
           [0014]      FIGS. 2A-2B  re flow diagrams illustrating a method of providing compositional guidance to a user capturing an image according to an exemplary embodiment. 
           [0015]      FIG. 3A  is an example of a compositional guidance polygon overlaid over an image. 
           [0016]      FIG. 3B  is an example of a final image after application of the compositional guidance. 
           [0017]      FIG. 4A  is an illustration of the coordinate system used in the compositional guidance method according to an exemplary embodiment. 
           [0018]      FIG. 4B  is an illustration of the calculated vertices of the compositional guidance polygon according to an exemplary embodiment. 
           [0019]      FIG. 5  is a flowchart illustrating the process of computing the location of the compositional guidance polygon according to an exemplary embodiment. 
           [0020]      FIG. 6  is an illustration determining the coordinates of the region of interest according to an exemplary embodiment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0021]      FIG. 1  is a representational view illustrating a general configuration of an imaging apparatus according to an exemplary embodiment. 
         [0022]    An imaging apparatus  100  includes a protection unit  102 , photographic lens  10 , a shutter  12 , an image sensor  14 , an analog to digital (A/D) converter  16 , a timing generation circuit  18 , and an image processing circuit  20 . The protection unit  102  serves as a cover to protect an imaging unit including the photographic lens  10  from soiling and breakage. The shutter  12  includes a diaphragm function. The image sensor  14  converts an optical image to electric signals. The A/D converter  16  coverts an analog signal output from the image sensor  14  to a digital signal. The timing generation circuit  18  supplies a clock signal and a control signal to the image sensor  14 , the A/D converter  16 , and a digital to analog (D/A) converter  26 . The timing generation circuit  18  is controlled by a memory control circuit  22  and a system control unit  50 . 
         [0023]    The image processing circuit  20  performs predetermined pixel interpolation and color conversion on data received from the A/D converter  16  or the memory control circuit  22 . Further, the image processing circuit  20  performs a predetermined calculation using the captured image data. Furthermore, the image processing circuit  20  performs a predetermined calculation using the captured image data and through-the-lens (TTL) auto-white balance (AWB) processing based on the calculation result. In white balance processing, block integration is performed by dividing a video signal into a plurality of blocks and acquiring an integration value of a color signal for each block to calculate the white balance. Further, white search integration is performed by converting a signal value of each pixel in the video signal onto a chromaticity coordinate and acquiring an integration value of the color signal for a predetermined region. A setting of an integration region on the chromaticity coordinate that is used in the white search integration is stored in the image processing circuit  20 . 
         [0024]    The imaging apparatus  100  further includes the memory control circuit  22 , an image display memory  24 , the D/A converter  26 , and an image display unit  28 . 
         [0025]    The memory control circuit  22  controls the A/D converter  16 , the timing generation circuit  18 , the image processing circuit  20 , the D/A converter  26 , a memory  30  and a compression/decompression circuit  32 . The data of the A/D converter  16  is written in the image display memory  24  or the memory  30  via the image processing circuit  20  and the memory control circuit  22 , or via the memory control circuit  22 . 
         [0026]    The image display unit  28  is, for example, a thin-film transistor (TFT) liquid crystal display (LCD). Image data for display that is written in the image display memory  24  is displayed on the image display unit  28  via the D/A converter  26 . An electronic finder function can be implemented by sequentially displaying the captured image data using the image display unit  28 . Further, the image display unit  28  can arbitrarily switch a display screen on and off according to an instruction from a system control unit  50 . If the image display unit  28  turns off the display, power consumption of the imaging apparatus  100  can be greatly reduced. 
         [0027]    The imaging apparatus  100  further includes the memory  30 , the compression/decompression circuit  32 , an exposure control unit  40 , a focusing control unit  42 , a zoom control unit  44 , a barrier control unit  46 , a flash unit  48 , and the system control unit  50 . 
         [0028]    The memory  30  stores captured still images and moving images. The memory  30  has a storage capacity large enough to store a predetermined number of still images and a moving image corresponding to a predetermined period. Therefore, a large amount of image data can be written in the memory  30  at high speed in both a continuous shooting mode of continuously shooting a plurality of still images and a panorama shooting mode. Further, the memory  30  can be used as a work area of the system control unit  50 . 
         [0029]    The compression/decompression circuit  32  compresses and decompresses the image data using adaptive discrete cosine transform (ADCT). The compression/decompression circuit  32  reads an image stored in the memory  30  and compresses or decompresses the image, and writes the processed data in the memory  30 . 
         [0030]    The system control unit  50  controls the entire imaging apparatus  100 . In one embodiment, the system control unit  50  is a single central processing unit. In another embodiment, the system control unit includes multiple central processing units. The exposure control unit  40  controls the shutter  12  that includes the diaphragm function. Further, the exposure control unit  40  includes a flash light amount control function in cooperation with the flash unit  48 . The focusing control unit  42  controls focusing of the photographic lens  10 . The exposure control unit  40  and the focusing control unit  42  are controlled by a TTL system. 
         [0031]    More specifically, the system control unit  50  performs auto-focus (AF) processing, automatic exposure (AE) processing, and electronic flash pre-emission (EF) processing according to the TTL system by controlling the exposure control unit  40  and the focusing control unit  42  based on a calculation result obtained by the image processing unit  20 . The zoom control unit  44  controls zooming of the photographic lens  10 . The barrier control unit  46  controls an operation of the protection unit  102 . The flash unit  48  includes a function of emitting AF auxiliary light and the light amount control function. 
         [0032]    Moreover, the imaging apparatus  100  includes a memory  52 , a display unit  54 , and a non-volatile memory  56 . 
         [0033]    The memory  52  stores constants, variables, and programs to be used in operations of the system control unit  50 . Further, the memory  52  stores a program diagram to be used in the AE processing. The program diagram is a table that defines a relationship between an aperture diaphragm diameter corresponding to an exposure value and a control value of shutter speed. 
         [0034]    The display unit  54  may include an LCD or a speaker that displays an operation state or a message using characters, images, and sound according to execution of a program by the system control unit  50 . One display unit  54  or a plurality of display units  54  may be provided near an operation unit  63  of the imaging apparatus  100  so that it is easily visible for a user. The display unit  54  may be configured as a combination of an LCD, a light-emitting diode (LED), and a sound generator. A part of the functions of the display unit  54  is installed within an optical finder  104 . 
         [0035]    Display contents of the display unit  54  which are displayed on the LCD may include indications of selected areas of interest, single shot/continuous shooting, self timer, a compression rate, a number of recorded pixels, a number of recorded shots, a remaining number of shots, a shutter speed, an aperture value, and exposure correction. 
         [0036]    Further, the display unit  54  may display on the LCD, indications such as, flash, red-eye reduction, macro shooting, buzzer setting, remaining amount of a clock battery, remaining amount of batteries, error information, information in a plurality of digits, a detached/attached state of a recording medium, a communication interface operation, and date and time. 
         [0037]    The display contents of the display unit  54  that are displayed in the optical finder  104  may include indications of in-focus, camera-shake warning, flash charge, shutter speed, aperture value, and exposure correction. 
         [0038]    The non-volatile memory  56  is an electrically erasable and recordable memory such as an electrically erasable programmable read-only memory (EEPROM). 
         [0039]    The imaging apparatus  100  further includes a mode dial  60 , a shutter switch (SW 1 )  61 , a shutter switch (SW 2 )  62 , and the operation unit  63  which are input units for a user to input various operation instructions to the system control unit  50 . Such input units are configured with a single device such as a switch, a dial, a touch panel, pointing using line-of-sight detection, and a speech recognition apparatus or a combination of a plurality of these devices. 
         [0040]    The mode dial  60  can be used to specify switching between functional modes such as power off, automatic shooting mode, shooting mode, panoramic shooting mode, composition guidance mode, reproduction mode, multiple screen reproducing/erasing mode, and personal computer (PC) connection mode. 
         [0041]    The shutter switch (SW 1 )  61  is switched on by a half stroke of a shutter button (not illustrated) and instructs start of AF processing, AE processing, AWB processing, and EF processing. 
         [0042]    The shutter switch (SW 2 )  62  is switched on by a full stroke of the shutter button (not illustrated) and instructs start of a series of processing. The series of processing include exposure processing to write signals read from the image sensor  14  into the memory  30  via the A/D converter  16  and the memory control circuit  22 , developing processing employing calculations performed by the image processing circuit  20  and the memory control circuit  22 , and recording processing. In the recording processing, the image data read from the memory  30  is compressed by the compression/decompression circuit  32  and then written into the recording media  200  and  210 . 
         [0043]    The operation unit  63  includes various buttons and touch panels, such as a menu button, a set button, a macro selection button, a multi-screen reproduction and page-advance button, a flash setting button, and a single-shot/serial-shot/self-timer selection button. Further, the operation unit  63  includes a forward (+) menu item selection button, a backward (−) menu item selection button, a forward (+) reproduction image search button, a backward (−) reproduction image search button, a shooting quality selection button, an exposure correction button, and a date/time set button. 
         [0044]    The imaging apparatus  100  further includes a power supply control unit  80 , connectors  82  and  84 , a power supply  86 , interfaces  90  and  94 , the optical finder  104 , a communication unit  110 , a connector (antenna)  112 , and a recording medium attachment/detachment state detection unit  98 . 
         [0045]    The power supply control unit  80  includes a battery detection circuit, a direct current (DC)-DC converter, and a switch circuit for switching the blocks to be energized. The power supply control unit  80  detects the attached/detached state of the battery, a battery type and the remaining battery power level, and controls the DC-DC converter based on the detection result and an instruction from the system controller  50 . The power supply control unit  80  then supplies a necessary voltage for a necessary period to each of the units including the recording medium. The power supply  86  may include a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a BNiCd battery, an NiMH battery, or an Li battery, and an alternate current (AC) adapter. 
         [0046]    Interfaces  90  and  94  transmit and receive data to and from the recording media  200  and  210  such as a memory card or a hard disk. The connectors  92  and  96  connect the imaging apparatus  100  and the recording media  200  and  210 . The recording medium attachment/detachment detection unit  98  detects whether the recording medium  200  or the recording medium  210  is connected to the connector  92  or the connector  96 . The present exemplary embodiment describes a case where there are two systems of interfaces and connectors for attaching the recording medium. However, there can be any number of systems of interfaces and connectors for attaching the recording medium. Further, interfaces and connectors pursuant to different standards may be combined. 
         [0047]    Cards in conformity with Personal Computer Memory Card International Association standards (PCMCIA cards) or cards in conformity with compact flash (CF) card standards may be used as the interfaces and connectors. In such a case, various communication cards such as a local area network (LAN) card, a modem card, a universal serial bus (USB) card, an Institute of Electrical and Electronics Engineers (IEEE) 1394 card, a P1284 card, a small computer system interface (SCSI) card, and a personal handyphone system (PHS) are connected. According to this configuration, image data and management information attached to the image data can be transmitted and received between other peripheral devices such as a computer and a printer. 
         [0048]    The optical finder  104  is a window for confirming an object to be captured without using the electronic viewfinder function of the image display unit  28 . A part of the functions of the display unit  54  including an indication of in-focus state, a camera shake warning, a flash charge state, a shutter speed, an aperture value, and exposure correction are displayed inside the optical finder  104 . 
         [0049]    The communication unit  110  includes various communication functions such as Recommended Standard (RS) 232C, USB, IEEE 1394, P1284, SCSI, modem, LAN, and wireless communication. 
         [0050]    The connector (antenna)  112  connects the imaging apparatus  100  with other devices via the communication unit  110 . The connector  112  functions as an antenna when performing wireless communication. 
         [0051]    The recording media  200  and  210  such as the memory card or the hard disk are detachably attached to the imaging apparatus  100 . The recording media  200  and  210  include recording units  202  and  212  configured by a semiconductor memory or a magnetic disk, and interfaces  204  and  214  respectively. Further, the recording media  200  and  210  includes connectors  206  and  216  for connecting with the imaging apparatus  100 . 
         [0052]      FIGS. 2A-2B  illustrate a method of providing compositional guidance to a user capturing an image using image capturing apparatus  100  according to an exemplary embodiment. First, in step S 202 , a preview image is generated. Generating preview images is well known in the art, and any known method for generating a preview image that would enable practice of the present embodiment is applicable. Thus, a detailed description of this step is omitted herein. 
         [0053]    Next, in step S 204 , the preview image is displayed. In step S 206  a determination is made if the compositional guidance settings have been placed in the “on” position. If the compositional guidance setting has not been placed in the “on” position, then in step S 208 , a determination is made whether the shutter switch  62  has been pressed. If shutter switch  62  has been pressed, then flow proceeds to step S 210 , where a digital image S 212  of a subject is captured. 
         [0054]    If, in step S 206 , the compositional guidance system has been placed in the “on” position, in step S 214 , the user selects one or more points of interest in the image currently being previewed. In another embodiment, if the user does not select a point of interest, the image capturing apparatus  100  automatically determines a likely point or points of interest by analyzing the image and identifying strong features. 
         [0055]    In step S 216 , the point or points of interest are identified by x-y coordinates. Then, in step S 218 , a process is performed on the image area surrounding the x-y coordinates of the point or points of interest in order to determine significant features. There are many known methods in the art to determine significant features. For example, one method determines the average colors in the area surrounding the selection in all color channels and then extracts every contiguous point in the frame with color channel values that are within the average colors of the area surrounding the point or points of interest. In addition to this example, any other known method that would enable practice of the present embodiment is applicable. 
         [0056]    The identification of these significant features allows for the determination, in step S 220 , of an area surrounding the x-y coordinates as the area of interest for each point. In step S 222 , a pre-determined mode of calculation is identified either by prior user selection or by default. The pre-determined modes of calculation include, but are not limited to, one of the following: center of gravity, geographic center, etc. Next, in step S 224 , the identified mode of calculation is used to calculate the center of the area of interest identified in step S 220 . In step S 226 , the center of each area of interest is identified using the calculated center of the area of interest. 
         [0057]    Steps S 228  through S 234  are performed in parallel to the steps S 218  through S 226 . Turning to step S 228 , the background of the image is extracted and areas of the background to be analyzed are then identified in step S 230 . A spatial analysis of the background is performed in step S 232  to determine the lines, patterns, and tilt factors of s 234 . Lines and patterns are associated with the structure of the image and the angle of the lines and patterns in relation to a horizontal line would define the tilt factor that has to be compensated. 
         [0058]    Flow then proceeds to step S 238 , where the composition guidance line is generated. The composition guidance line is generated based on information about the center of the area of interest, the lines and patterns in the background, and predetermined rules. The predetermined rules are identified in, and include, but are not limited to, rules of thirds, avoidance of centering dominant vertical, horizontal or diagonal edge, etc. In step S 240 , the generated composition guidance line is superimposed over the preview image. 
         [0059]    In step S 242 , a determination is made whether shutter switch  62  has been pressed. If shutter switch  62  has been pressed, then a digital image S 246  of a subject is captured in step S 244 . If shutter switch  62  is not pressed then, in step S 248 , a check is made whether the user has changed the framing. If the user changed the framing, which can include changes in tilt or zoom, then in step S 250 , the resulting changes to the points of interest are tracked and updated. The process then returns to step S 216 . If there are no changes in the framing, then the process returns to S 238 . 
         [0060]      FIGS. 3A and 3B  illustrate exemplary images and are provided for example purposes only. 
         [0061]      FIG. 3A , illustrates an example of a preview image with a compositional guidance polygon overlaid on an image. As illustrated in the image, the horizon is slightly tilted and not perfectly horizontal, and the main object of interest, the island, needs to be more prominent in the image in order to make better use of the image resolution.  FIG. 3B  illustrates a final image resulting from the user making appropriate adjustments indicated by the compositional guidance. 
         [0062]    The compositional guidance in the present example applies the Rule of Thirds to the selected point of interest in the image, i.e., the island, to correct the tilted horizon. In the present case, under the Rule of Thirds, one should imagine the image as divided into nine equal parts by two equally spaced horizontal lines and two equally spaced vertical lines, with important compositional elements placed along these lines or their intersection(s). 
         [0063]    The coordinate system used in the present example is illustrated in  FIG. 4A . Per  FIG. 4A , the origin is set at the lower left corner of the image, the x-axis lies in the horizontal direction, and the y-axis lies in the vertical direction. The tilt is measured as an angle increasing from 0 degrees when parallel to the x-axis to 90 degrees when parallel with the y-axis.  FIG. 4B  identifies the coordinates of the vertices of the compositional guidance polygon and the coordinates of the Region of Interest (ROI). 
         [0064]      FIG. 5  is a flowchart illustrating the process of computing the location of the compositional guidance polygon according to an exemplary embodiment. First in step S 500 , a preview image is captured, and then in step S 502 , the point of interest in the image is selected, e.g., the island in  FIG. 3A . In step S 504  the horizon line is extracted. This can be performed by a horizon detection algorithm based on color in which the most prominent edge can be found based on Canny edge detection and Hough transformation. (See  Visual Communications and Image Processing  2008. Edited by Pearlman, William A.; Woods, John W.; Lu, Ligang. Proceedings of the SPIE, Volume 6822, pp. 682220-682220-9 (2008)). 
         [0065]    Next, in step S 506  the tilt angle of the horizon line is determined as an angle in relation to a perfect horizontal line between two points on the horizon line using the equation 
         [0000]      Tilt angle=arctan( yR−yL )/( xR−xL ). 
         [0000]    where xR is the x-coordinate of the horizon edge with the largest x-coordinate value; xL is the x-coordinate value of the horizon edge with the smallest x-coordinate value; yR is the y-coordinate of the horizon edge with the largest y-coordinate value; yL is the y-coordinate value of the horizon edge with the smallest y-coordinate value. 
         [0066]    In step S 508  the coordinates of the region of interest (ROI) are determined. The process for this determination is illustrated in  FIG. 6 . Turning to  FIG. 6 , in step S 600  the average colors in all color channels present in and around the point of interest are determined. Then, in step S 604 , the tolerance value, which was preset either by the image capturing apparatus&#39; 100 manufacturer or by a user, is determined, where every contiguous point in the frame with color channel values that are within the average colors of the ROI and within the preset tolerance are extracted. This range is determined by (average−tolerance) to (average+tolerance). 
         [0067]    Next Xmin of step S 606 , Ymin of step S 608 , Xmax of step S 610 , and Ymax of step S 612  are determined by calculating the centroid of the ROI. The centroid of a non-self-intersecting closed polygon defined by n vertices (x 0 , y 0 ), (x 1 , y 1 ), . . . , (x n-1 , y n-1 ) is the point (C x , C y ), where 
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         [0000]    and where A is the polygon&#39;s signed area, 
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         [0068]    In these formulas, the vertices are presumed to be numbered in order of their occurrence along the polygon&#39;s perimeter, and the vertex (x n , y n ) is presumed to be the same as (x 0 , y 0 ). Note that if the points are numbered in clockwise order the area A, computed as above, will have a negative sign; but the centroid coordinates will be correct even in this case. 
         [0069]    Returning to  FIG. 5 , in step S 510 , the maximum and minimum coordinates of the ROI, along with the four coordinates of the two points of the horizon line and the angle of tilt of the horizon, are used to determine the vertices of the guidance polygon. Additionally, a pre-set margin distance “D” between the dynamic frame edge and ROI is used. 
         [0070]    If the tilt angle is determined to be greater than or equal to zero, than the vertices of the compositional guidance frame are determined by: 
         [0071]    Xleft_down=Xmin−D 
         [0072]    Yleft_down=Ymin−D 
         [0073]    Xleft_up=Xmin−D 
         [0074]    Yleft_up=Ymax+D 
         [0075]    Xright_down=Xmax+D 
         [0076]    Yright_down=tan(tilt angle)*(Xmax−Xmin)+Yleft_down 
         [0077]    Xright_up=Xmax+D 
         [0078]    Yright_up=tan(tilt angle)*(Xmax−Xmin)+Yleft_up 
         [0079]    If the tilt angle is determined to be less than zero, than the vertices of the compositional guidance frame are determined by: 
         [0080]    Xleft_down=Xmin−D 
         [0081]    Yleft_down=tan(tilt angle)*(Xmax−Xmin)+Yright_down 
         [0082]    Xleft_up=Xmin−D 
         [0083]    Yleft_up=tan(tilt angle)*(Xmax−Xmin)+Yright_up 
         [0084]    Xright_down=Xmax+D 
         [0085]    Yright_down=Ymin−D 
         [0086]    Xright_up=Xmax+D 
         [0087]    Yright_up=Ymax+D 
         [0088]    Additionally, the compositional guidance polygon is positioned to position the centroid of the ROI near the closest intersection of imaginary horizontal and vertical lines that divides the dynamic frame in nine equal parts according to the Rule of Thirds. 
         [0089]    According to other embodiments contemplated by the present disclosure, example embodiments may include a computer processor such as a single core or multi-core central processing unit (CPU) or micro-processing unit (MPU), which is constructed to realize the functionality described above. The computer processor might be incorporated in a stand-alone apparatus or in a multi-component apparatus, or might comprise multiple computer processors that are constructed to work together to realize such functionality. The computer processor or processors execute a computer-executable program (sometimes referred to as computer-executable instructions or computer-executable code) to perform some or all of the above-described functions. The computer-executable program may be pre-stored in the computer processor(s), or the computer processor(s) may be functionally connected for access to a non-transitory computer-readable storage medium on which the computer-executable program or program steps are stored. For these purposes, access to the non-transitory computer-readable storage medium may be a local access such as by access via a local memory bus structure, or may be a remote access such as by access via a wired or wireless network or Internet. The computer processor(s) may thereafter be operated to execute the computer-executable program or program steps to perform functions of the above-described embodiments. 
         [0090]    According to still further embodiments contemplated by the present disclosure, example embodiments may include methods in which the functionality described above is performed by a computer processor such as a single core or multi-core central processing unit (CPU) or micro-processing unit (MPU). As explained above, the computer processor might be incorporated in a stand-alone apparatus or in a multi-component apparatus, or might comprise multiple computer processors which work together to perform such functionality. The computer processor or processors execute a computer-executable program (sometimes referred to as computer-executable instructions or computer-executable code) to perform some or all of the above-described functions. The computer-executable program may be pre-stored in the computer processor(s), or the computer processor(s) may be functionally connected for access to a non-transitory computer-readable storage medium on which the computer-executable program or program steps are stored. Access to the non-transitory computer-readable storage medium may form part of the method of the embodiment. For these purposes, access to the non-transitory computer-readable storage medium may be a local access such as by access via a local memory bus structure, or may be a remote access such as by access via a wired or wireless network or Internet. The computer processor(s) is/are thereafter operated to execute the computer-executable program or program steps to perform functions of the above-described embodiments. 
         [0091]    The computer-readable storage medium on which a computer-executable program or program steps are stored may be any of a wide variety of tangible storage devices which are constructed to retrievably store data, including, for example, any of a flexible disk (floppy disk), a hard disk, an optical disk, a magneto-optical disk, a compact disc (CD), a digital versatile disc (DVD), micro-drive, a read only memory (ROM), random access memory (RAM), erasable programmable read only memory (EPROM), electrically erasable programmable read only memory (EEPROM), dynamic random access memory (DRAM), video RAM (VRAM), a magnetic tape or card, optical card, nanosystem, molecular memory integrated circuit, redundant array of independent disks (RAID), a nonvolatile memory card, a flash memory device, a storage of distributed computing systems and the like. The storage medium may be a function expansion unit removably inserted in and/or remotely accessed by the apparatus or system for use with the computer processor(s). 
         [0092]    While aspects of the present disclosure have been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications, equivalent structures and functions.