Abstract:
An information processing apparatus and method provide logic for processing information. In one implementation, a computer-implemented method includes receiving spatial positions associated with a plurality of images. The method determines displacements of the images in opposing first and second horizontal directions, based on at least the spatial positions. The method then generates, using a processor, first and second composites of the images, based on the determined displacements.

Description:
TECHNICAL FIELD 
     This application is a National Stage Patent Application of PCT International Patent Application No. PCT/JP2012/001960 (filed on Mar. 21, 2012) under 35 U.S.C. §371, which claims the benefit of priority from Japanese Patent Application JP2011-069311, filed on Mar. 28, 2011, the entire contents of which are all hereby incorporated by reference in their entirety. 
     The disclosed exemplary embodiments relate to an image processing apparatus and image processing methods. More particularly, the disclosed exemplary embodiments relate to an image processing apparatus and an image processing method that process multiple images captured at varied positions in a depth direction to generate a left-eye image and a right-eye image for display of a stereoscopic image. 
     BACKGROUND ART 
     For example, PTL 1 describes a display of a stereoscopic image using binocular disparity, as illustrated in  FIG. 8 .  FIG. 8  shows the relationship between positions where left and right images of objects (e.g., bodies) are displayed on a screen and positions where their stereoscopic images are reproduced on the screen in the display of stereoscopic images using the binocular disparity. For example, as for an object A whose left image La is shifted rightward for display on the screen, and whose right image Ra is shifted leftward for display on the screen, as shown in the drawing, its stereoscopic image is reproduced at a position on a near side with respect to a screen surface because left and right lines of sight intersect with each other on the near side with respect to the screen surface. Reference letter DPa denotes a horizontal disparity vector for the object A. 
     In addition, for example, as for an object B whose left image Lb and right image Rb are displayed at the same position on the screen, as shown in the drawing, its stereoscopic image is reproduced at a position on the screen surface because the left and right lines of sight intersect with each other on the screen surface. Furthermore, for example, as for an object C whose left image Lc is shifted leftward for display on the screen and whose right image Rc is shifted rightward for display on the screen, as shown in the drawing, its stereoscopic image is reproduced at a position on a far side with respect to the screen surface because the left and right lines of sight intersect with each other on the far side with respect to the screen surface. Reference letter DPc denotes a horizontal disparity vector for the object C. 
     For example, fluorescence microscopes have heretofore been used to capture images of living bodies, such as cells of human beings, at varied positions in a depth direction. The fluorescence microscopes can be used to capture an image at each depth-direction position without being blocked by bodies on the near side. 
     The fluorescence microscopes are microscopes in which fluorescent materials are attached to, for example, cells to be observed, the fluorescent materials are irradiated with laser light or the like to excite the fluorescent materials, and light emitted when the excited state is returned to a ground state is observed. For example, confocal microscopes and two-photon excitation microscopes are known as the fluorescence microscopes, although a detailed description of them is omitted here. 
     CITATION LIST 
     Patent Literature 
     
         
         PTL 1: Japanese Unexamined Patent Application Publication No. 2005-6114 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     As described above, an addition and averaging process for each pixel has often been applied to multiple images captured at varied positions in the depth direction in the manner described above to generate one two-dimensional image for evaluation.  FIG. 9  illustrates an exemplary application of the addition and averaging processes to twenty images to generate one two-dimensional image. Reference numerals “# 1 ” to “# 20 ” denote captured images and reference numeral “# 1 -# 20 ” denotes the two-dimensional image that is generated. In this case, although the multiple images are captured at varied depth-direction positions and have three-dimensional information, the multiple images are degenerated and evaluated in a two-dimensional state and the three-dimensional information is not effectively used. 
     Furthermore, for example, a viewpoint is varied and moved, or hatching is performed, to highlight the hierarchical relationship in the related art in order to achieve stereoscopic effect. However, when the viewpoint is varied and moved, it is necessary to perform an operation reflecting a user&#39;s viewpoint and, thus, there is a disadvantage in that it is not possible to focus on the evaluation. In addition, the hatching for highlighting the hierarchical relationship is not sufficient to achieve the stereoscopic effect. 
     The disclosed exemplary embodiments may effectively leverage three-dimensional information associated with multiple images captured at varied depth-direction positions to allow an image having sufficient stereoscopic effect to be displayed. 
     Solution to Problem 
     Consistent with an exemplary embodiment, a computer-implemented method receives data associated with a plurality of images. The data specifies spatial positions of the images. The method includes determining displacements of the images in a first horizontal direction and a second horizontal direction, based on at least the spatial positions. The first horizontal direction is opposite to the second horizontal direction. The method includes generating, using a processor, first and second composites of the images, based on the determined displacements. 
     Consistent with a further exemplary embodiment, an information processing apparatus includes a receiving unit configured to receive data associated with a plurality of images. The data specifies spatial positions of the images. A determination unit is configured to determine displacements of the images in a first horizontal direction and a second horizontal direction, based on at least the spatial positions. The first horizontal direction is opposite to the second horizontal direction. A generating unit is configured to generate first and second composites of the images, based on the determined displacements. 
     Consistent with another exemplary embodiment, a tangible, non-transitory computer-readable medium stores instructions that, when executed by at least one processor, cause the processor to perform a method that includes receiving data associated with a plurality of images. The data specifies spatial positions of the images. The method includes determining displacements of the images in a first horizontal direction and a second horizontal direction, based on at least the spatial positions. The first horizontal direction is opposite to the second horizontal direction. The method includes generating, using a processor, first and second composites of the images, based on the determined displacements. 
     Advantageous Effects of invention 
     According to the disclosed exemplary embodiments, it is possible to effectively use three-dimensional information on multiple images captured at varied depth-direction positions to allow an image having sufficient stereoscopic effect to be displayed. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is a block diagram showing an example of the configuration of an image processing apparatus, in accordance with a first exemplary embodiment. 
         FIG. 2  is a diagram for describing a shifting process and an addition and averaging process of images in an image generating unit, consistent with disclosed exemplary embodiments. 
         FIG. 3  is a diagram showing an example of the horizontal size, the vertical size, and the depth distance in an image captured in a real space and the horizontal size, the vertical size, and the depth on 3D monitor display, consistent with disclosed exemplary embodiments. 
         FIG. 4  includes diagrams for describing the (linear and nonlinear) relationships between the depth-direction positions and the amounts of shift of images, consistent with disclosed exemplary embodiments. 
         FIG. 5  is a block diagram showing an example of the configuration of an image processing apparatus, in accordance with a second exemplary embodiment. 
         FIG. 6  includes diagrams for describing hidden surface elimination in an image generating unit, consistent with disclosed exemplary embodiments. 
         FIG. 7  is a diagram for describing the hidden surface elimination when only a nearest image has an effective area, consistent with disclosed exemplary embodiments. 
         FIG. 8  is a diagram for describing the relationship between positions where left and right images of objects are displayed on a screen and positions where their stereoscopic images are reproduced on the screen in display of stereoscopic images using binocular disparity. 
         FIG. 9  is a diagram for describing a process of performing the addition and averaging process for every pixel to multiple images captured at varied positions in a depth direction to generate one two-dimensional image in related art. 
         FIG. 10  is a diagram of an exemplary computer system, consistent with disclosed exemplary embodiments. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Below, exemplary embodiments of the present disclosure will be described. Here, the description will be performed in the order below: 
     1. First embodiment; 
     2. Second embodiment; 
     3. Modifications; and 
     4. Exemplary Computer Systems. 
     1. First Embodiment 
     a. Configuration of Image Processing Apparatus 
       FIG. 1  shows an example of the configuration of an image processing apparatus  100 , in accordance with a first exemplary embodiment. This image processing apparatus  100  includes an image generating unit  101 , an amount-of-shift determining unit  102 , and an image-quality adjusting unit  103 . This image processing apparatus  100  generates a left-eye image and a right-eye image for display of a stereoscopic image on the basis of multiple (e.g., N-number) images (e.g., fluorescence microscope images) captured at varied depth-direction positions and received at a corresponding receiving unit. 
     The image generating unit  101  performs a process of shifting multiple images (image data) in opposite directions depending on their depth-direction positions with respect to the image at a reference position to generate a group of left-eye images and a group of right-eye images to which disparity is given. Then, the image generating unit  101  performs an addition and averaging process for pixels for each pixel position to the respective image groups to generate a left-eye image SL and a right-eye image SR. 
       FIG. 2  shows an example of processing in the image generating unit  101 , consistent with a disclosed embodiment. In this example of processing, eight images # 1  to # 8  captured at sequentially varied positions at regular intervals in the depth direction are processed, and the image # 4  is used as the image at the reference position. 
     The image generating unit  101  performs the process of horizontally shifting the eight images depending on their depth-direction positions with respect to the image at the reference position (the image # 4 ) to generate the multiple images composing the group of left-eye images. Specifically, the image generating unit  101  sequentially shifts the images (the images # 3  to # 1 ) on a near side in one horizontal direction depending on their depth-direction positions with respect to the image at the reference position and shifts the images (the images # 5  to # 8 ) on a far side in the other horizontal direction depending on their depth-direction positions with respect to the image at the reference position. 
     In this case, the image generating unit  101  sequentially shifts the images on the near side with respect to the image at the reference position (the image # 4 ) in the horizontal direction by “+d”. This causes the nearest image (the image # 1 ) to be horizontally shifted with respect to the image at the reference position (the image # 4 ) by “+3d′”. In addition, in this case, the image generating unit  101  sequentially shifts the images on the far side with respect to the image at the reference position (the image # 4 ) in the horizontal direction by “−d′”. This causes the furthest image (the image # 8 ) to be horizontally shifted with respect to the image at the reference position (the image # 4 ) by “−4d′”. Here, “d′” indicates an amount of shift determined by the amount-of-shift determining unit  102  on the basis of imaging conditions and display conditions in a manner described below. 
     Then, the image generating unit  101  performs the addition and averaging process for pixels (pixel data) for each pixel position to the multiple images (the images # 1  to # 8 ) composing the group of left-eye images subjected to the shifting process to generate the left-eye image SL (# 1 -# 8 ). In this case, since the shifting process is performed, the number of pixels to be subjected to the addition and averaging process is any of one to eight depending on the pixel position. 
     In addition, the image generating unit  101  performs the process of horizontally shifting the eight images depending on their depth-direction positions with respect to the image at the reference position (the image # 4 ) to generate the multiple images composing the group of right-eye images. Specifically, the image generating unit  101  sequentially shifts the images (the images # 3  to # 1 ) on the near side in the other horizontal direction depending on their depth-direction positions with respect to the image at the reference position and shifts the images (the images # 5  to # 8 ) on the far side in the one horizontal direction depending on their depth-direction positions with respect to the image at the reference position. This shifting process is a process in which symmetric shift is performed in a direction opposite to the one in the above case in which the multiple images composing the group of left-eye images are generated. 
     In this case, the image generating unit  101  sequentially shifts the images on the near side with respect to the image at the reference position (the image # 4 ) in the horizontal direction by “−d′”. This causes the nearest image (the image # 1 ) to be horizontally shifted with respect to the image at the reference position (the image # 4 ) by “−3d′”. In addition, in this case, the image generating unit  101  sequentially shifts the images on the far side with respect to the image at the reference position (the image  44 ) in the horizontal direction by “+d′”. This causes the furthest image (the image # 8 ) to be horizontally shifted with respect to the image at the reference position (the image # 4 ) by “+4d′”. 
     Then, the image generating unit  101  performs the addition and averaging process for pixels (pixel data) for each pixel position to the multiple images (the images # 1  to # 8 ) composing the group of right-eye images subjected to the shifting process to generate the right-eye image SR (# 1 -# 8 ). In this case, since the shifting process is performed, the number of pixels to be subjected to the addition and averaging process is any of one to eight depending on the pixel position. 
     Referring back to  FIG. 1 , the amount-of-shift determining unit  102  determines the amount of shift d on the basis of the imaging conditions and the display conditions. A method of determining the amount of shift d′ in the amount-of-shift determining unit  102  will now be described in detail. Here,  FIG. 3  shows an example of the horizontal size, the vertical size, and the depth distance in an image captured in a real space and the horizontal size, the vertical size, and the depth on 3D monitor display. 
     Provided that a dot pitch of the captured image is denoted by dps[m], the depth distance on the captured image is calculated by Zs[pixel]=Zs[m]/dps. In contrast, a depth Ld[m] reproduced in stereoscopic display is calculated by Ld=Ls*de/(de+d). Here, Ls denotes a viewing distance, de denotes a distance between left and right eyes, and d denotes a disparity (values on the near side are defined as positive values). In order to generate a stereoscopic image in accordance with the angle of view when the captured image is displayed, d is set to a value that is equal to Zs. 
     Here, provided that the disparity of a nearest target image is denoted by dmax and the disparity of a furthest target image is denoted by drain, the following Equation (1) is established: 
     
       
         
           
             
               
                 
                   
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     Here, dpd denotes the dot pitch on the display. A difference delta-d between dmax and dmin is represented by the following Equation (2) from Equation (1) and delta-d is represented by a pixel value according to Equation (3): 
     
       
         
           
             
               
                 
                   
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     Here, if all the parameters are not available, the parameters may be set in advance in the following manner: 
     (1) The display is a 46V-size panel of 1,920*1,080 and the dot pitch dpd is equal to 0.053 m. 
     (2) The viewing distance Ls is equal to 3H (three times the height of the display). 
     (3) The distance de between left and right eyes is equal to 6.5 cm. 
     In addition, d′ may be appropriately multiplied by a constant. In this case, the scaling parameter s is adjusted. Furthermore, if delta-d exceeds a comfortable disparity range, d′ is reduced to fit d′ into the comfortable disparity range. In this case, the scaling parameter s is adjusted. The comfortable disparity range can be calculated from, for example, an assumed viewing distance or the screen size, although a detailed description of the above calculation is omitted herein. For example, the range in which comfortable viewing is realized with a 46V-size TV is a depth of 0.5 m (near side) to 1.5 m (far side) at a viewing distance of 1.7 m and is represented by −56 pixels (near side) to 55 pixels (far side) in replacement by the disparity. 
     In addition, the relationship between the depth-direction positions and the amounts of shift of images is linearly set, as shown in  FIG. 4 , in the above description. Accordingly, the process of sequentially shifting the eight images # 1  to # 8  captured at sequentially varied positions at regular intervals in the depth direction by the amount of shift d′ is performed. In this case, the disparity to be given to each image is calculated by equally dividing delta-d. 
     However, the relationship between the depth-direction positions and the amounts of shift of images may be nonlinearly set, as shown in  FIG. 4( b ) . In this case, the disparity to be given to each image is calculated by nonlinearly dividing delta-d. Since the relationship between the disparity and the depth is originally nonlinear, nonlinearly setting the relationship between the depth-direction positions and the amounts of shift of the images in the above manner allows the depth to be properly reproduced. 
     Referring back to  FIG. 1 , the image-quality adjusting unit  103  performs image quality adjustment, such as contrast adjustment, to the left-eye imago SL and the right-eye image SR generated in the image generating unit  101  to output a left-eye image SL′ and a right-eye image SR′ subjected to the image quality adjustment. In this case, for example, expanding a dynamic range of each image generated in the image generating unit  101  allows a dark image to be adjusted to a bright image to make the image easily viewable. 
     An operation of the image processing apparatus  100  shown in  FIG. 1  will be described. Multiple images (image data) captured at varied depth-direction positions are supplied to the image generating unit  101 . In addition, parameters indicating the imaging conditions, such as the dot pitch of the captured images and the depth distance of the captured images, and the display conditions, such as the viewing distance and the distance between left and right eyes, are supplied to the amount-of-shift determining unit  102 . Then, in the amount-of-shift determining unit  102 , the amount of shift d′ is determined on the basis of, for example, Equation (5). This amount of shift d′ is used in the process of shifting each image in the image generating unit  101 . 
     In the image generating unit  101 , the process of shifting the multiple (n-number) images in opposite directions depending on their depth-direction positions with respect to the image at the reference position is performed to generate the group of left-eye images and the group of right-eye images to which the disparity is given. Then, in the image generating unit  101 , the addition and averaging process for pixels for each pixel position is performed to the respective image groups to generate the left-eye image SL and the right-eye image SR. 
     The left-eye image SL and the right-eye image SR generated in the image generating unit  101  are supplied to the image-quality adjusting unit  103 . In the image-quality adjusting unit  103 , the image quality adjustment, such as the contrast adjustment, is performed to the left-eye image SL and the right-eye image SR. For example, the dynamic range of each image generated in the image generating unit  101  is expanded to adjust a dark image to a bright image. Then, the left-eye image SL and the right-eye image SR′ subjected to the image quality adjustment are output from the image-quality adjusting unit  103 . 
     As described above, in the image processing apparatus  100  shown in  FIG. 1 , the left-eye image SL and the right-eye image SR to which the disparity is given are generated on the basis of multiple images captured at varied positions in the depth direction in the image generating unit  101 . Specifically, in the image generating unit  101 , the process of shifting the multiple images captured at varied positions in the depth direction in opposite directions depending on their depth-direction positions with respect to the image at the reference position is performed to generate the group of left-eye images and the group of right-eye images to which the disparity is given. 
     Then, in this image generating unit  101 , the addition and averaging process for pixels for each pixel position is performed to the respective image groups to generate the left-eye image SL and the right-eye image SR. Accordingly, three-dimensional information on the multiple images captured at varied depth-direction positions is effectively used to generate the left-eye image SL and the right-eye image SR to which the disparity is given, thus allowing an image having sufficient stereoscopic effect to be displayed. 
     Furthermore, in the image processing apparatus  100  shown in  FIG. 1 , the left-eye image SL and the right-eye image SR generated in the image generating unit  101  are supplied to the image-quality adjusting unit  103  where the image quality adjustment, such as the contrast adjustment, is performed. Accordingly, for example, the dynamic range of each of the images SL and SR generated in the image generating unit  101  is expanded to allow a dark image to be adjusted to a bright image, thus making the stereoscopic image easily viewable. 
     2. Second Embodiment 
     a. Example of Configuration of Image Processing Apparatus 
       FIG. 5  shows an example of the configuration of an image processing apparatus  100 A, in accordance with a second exemplary embodiment. This image processing apparatus  100 A includes an image generating unit  101 A, the amount-of-shift determining unit  102 , and the image-quality adjusting unit  103 . The same reference numerals are used in  FIG. 5  to identify the corresponding components in  FIG. 1A  detailed description of such components is appropriately omitted herein. 
     This image processing apparatus  100 A generates a left-eye image and a right-eye image for display of a stereoscopic image on the basis of multiple images captured at varied depth-direction positions, as in the image processing apparatus  100  shown in  FIG. 1 . However, in this image processing apparatus  100 A, since hidden surface elimination is performed in the image generating unit  101 A, for example, the image at each depth-direction position, in which a body on the near side unexpectedly appears, is capable of being processed as the multiple (n-number) images, instead of the fluorescence microscope image. 
     The image generating unit  101 A performs the process of shifting multiple (n-number) images in opposite directions depending on their depth-direction positions with respect to the image at the reference position to generate a group of left-eye images and a group of right-eye images to which the disparity is given. Then, the image generating unit  101 A performs the addition and averaging process for pixels for each pixel position to the respective image groups to generate the left-eye image SL and the right-eye image SR. This processing is the same as the processing in the image generating unit  101  in the image processing apparatus  100  shown in  FIG. 1 . 
     The image generating unit  101 A performs the hidden surface elimination on the basis of information on an effective area when the addition and averaging process is performed to each group of images, unlike the image generating unit  101 . Here, the effective area indicates the area of a body actually existing at the position where each image is captured. For example, the information on the effective area may be manually provided by a user. Alternatively, for example, as for the information on the effective area, a portion having a higher spatial frequency or a portion having a lower spatial frequency may be extracted in, for example, the image generating unit  101 A and the extracted portion may be used as the effective area. Incidentally, in  FIG. 5 , the information on the effective area is supplied from the outside of the image generating unit  101 A. 
     The hidden surface elimination will now be described.  FIG. 6( a )  shows a casein which the hidden surface elimination is not performed, consistent with disclosed embodiments. In this case, the accumulated weight at each pixel position is equal to “1/the number of pixels”. For example, the accumulated weight at pixel positions where eight images are overlapped with each other is equal to ⅛. In contrast,  FIG. 6( b )  shows a case in which the hidden surface elimination is performed, consistent with disclosed embodiments. In this case, the accumulated weight at each pixel position with no effective area is equal to “1/the number of pixels”. However, the accumulated weight with in the effective area is equal to one, and the accumulated weight of an image on the far side at a portion corresponding to the hidden surface of the effective area of the image on the near side is equal to zero. Here, the hidden surface elimination is not limited to the method shown in  FIG. 6( b ) . 
       FIG. 7  shows the hidden surface elimination in a case in which only the nearest image (the image # 1 ) has the effective area, consistent with disclosed embodiments. Here, only the processing in the left-eye image SL is shown in  FIG. 7  for simplicity of the drawing. In this case, at each pixel position within the effective area of the image # 1 , the pixel in the image # 1  is directly used as the pixel in the left-eye image SL (# 1 -# 8 ). In contrast, at each pixel position outside the effective area of the image # 1 , the pixels in each image are subjected to the addition and averaging process to use the result as the left-eye image SL (# 1 -# 8 ). 
     The remaining configuration of the image processing apparatus  100 A shown in  FIG. 5  is the same as the configuration of the image processing apparatus  100  shown in  FIG. 1 , and the image processing apparatus  100 A shown in  FIG. 5  operates in the same manner as the image processing apparatus  100  shown in  FIG. 1 . 
     The image processing apparatus  100 A shown in  FIG. 5  has the same advantages as those of the image processing apparatus  100  shown in  FIG. 1 . Further more, in the image processing apparatus  100 A shown in  FIG. 5 , in the image generating unit  101 A, the hidden surface elimination is performed in the generation of the left-eye image SL and the right-eye image SR by performing the addition and averaging process for pixels for each pixel position to the group of left-eye images and the group of right-eye images (refer to  FIG. 6( b ) ). Accordingly, for example, the image at each depth-direction position, in which a body on the near side unexpectedly appears, is capable of being processed as the multiple (n-number) images, instead of the fluorescence microscope image. In other words, the hidden surface elimination can be performed to generate the left-eye image SL and the right-eye image SR without using erroneous three-dimensional information on each image. 
     3. Modifications 
     The multiple images captured at varied depth-direction positions are images captured by a microscope, such as a fluorescence microscope, in the embodiments described above. However, the present technology is also applicable to cases in which other multiple images captured at varied depth-direction positions are processed to generate left-eye images and right-eye images for display of stereoscopic images. 
     4. Exemplary Computer Systems 
     In an embodiment, the functions of the above-described apparatus, and the various units associated with the apparatus, can be achieved using, for example, a computer system  1000  shown in  FIG. 10 . Further, in an additional embodiment, the functions of one or more of the structural elements, sections, and units may be achieved by controlling computer system  1000  using instructions stored on a tangible, non-transitory computer-readable storage medium. In such embodiments, examples of computer system  1000  include, but are not limited to a personal computer, a laptop computer, a tablet computer, a mobile phone, a smart phone, a personal digital assistance (PDA), mobile information terminal, and/or a mobile game console. 
     As shown in  FIG. 10 , computer system  1000  includes a central processing unit. (CPU)  1002 , a host bus  1008 , a bridge  1010 , and a tangible computer-readable storage media, examples of which include a read only memory (ROM)  1004 , and a random access memory (RAM)  1006 . Furthermore, computer system  1000  includes an external bus  1012 , an interface  1014 , an input unit  1016 , an output unit  1018 , a storage unit  1020 , a drive  1022 , a connection port  1024 , and a communication unit  1026 . 
     CPU  1002  may function as an arithmetic processing unit or a control unit, for example, and controls the entire operation or a part of the operation of each structural element based on various instructions stored within ROM  1004 , RAM  1006 , storage unit  1020 , or a removable recording medium  1028 . ROM  1004  may be configured to store, for example, a instructions to be loaded on CPU  1002  or data or the like used in an arithmetic operation. RAM  1006  temporarily or permanently stores, for example, instructions to be loaded on CPU  1002  or various parameters or the like arbitrarily changed in execution of a program. 
     These structural elements are connected each other by, for example, host bus  1008  capable of performing high-speed data transmission. Host bus  1008  is connected through bridge  1010  to external bus  1012  whose data transmission speed is relatively low, for example. Furthermore, input unit  1016  may include, for example, a mouse, a keyboard, a touch panel, a button, a switch, or a lever. Also, input unit  1016  may be a remote control that can transmit a control signal by using an infrared ray or other radio waves. 
     Output unit  1018  may be a display device that includes, but is not limited to, a cathode ray tube (CRT), a liquid crystal display (LCD), a plasma display panel (PDP), an electro-luminescence display (ELD), and audio output device (e.g., a speaker or headphones), a printer, a mobile phone, and/or a facsimile, that may provide a visual or auditory notification to a user of acquired information. 
     Storage unit  1020  is an example of a tangible, non-transitory computer-readable storage medium or device for storing various data. Storage unit  1020  may include, for example, a magnetic storage device such as a hard disk drive (HDD), a semiconductor storage device, an optical storage device, a magneto-optical storage device. 
     Drive  1022  is a device that reads information recorded on removable recording medium  1028  such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory, or writes information in removable recording medium  1028 . Removal recording medium  1028  is another example of a tangible, non-transitory storage medium, for example, a DVD medium, a Blu-ray medium, an HD-DVD medium, various types of semiconductor storage media, or the like. Removable recording medium  1028  may be, for example, an electronic device or an IC card on which a non-contact IC chip is mounted. The IC is an abbreviation for Integrated Circuit. 
     Connection port  1024  may be a port that includes, but is not limited to, a USB port, an IEEE1394 port, a SCSI, an RS-232C port, or a port for connecting an externally connected device  1030 , such as an optical audio terminal. Externally connected device  1030  may be, for example, a printer, a mobile music player, a digital camera, a digital video camera, or an IC recorder. 
     Communication unit  1026  is a communication device to be connected to a network  1032 , and is, for example, a communication card for a wired or wireless LAN, Bluetooth, or wireless USB, an optical communication router, an ADSL router, or a modem for various types of communication. Network  1032  connected to communication unit  1026  is configured from a wire-connected or wirelessly connected network, and is the Internet, a home-use LAN, infrared communication, visible light communication, broadcasting, or satellite communication, for example. 
     It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof. 
     It should be noted that the present disclosure can also take the following configurations. 
     (1) 
     An image processing apparatus comprising: 
     an image generating unit that processes a plurality of images captured at varied positions in a depth direction to generate a left-eye image and a right-eye image, 
     wherein the image generating unit performs a process of shifting the plurality of images in opposite directions depending on their depth-direction positions with respect to the image at a reference position to generate a group of left-eye images and a group of right-eye images to which disparity is given and performs an addition and averaging process for pixels for each pixel position to the respective image groups to generate the left-eye image and the right-eye image. 
     (2) 
     The image processing apparatus according to (1), 
     wherein the image generating unit performs the process of sequentially shifting the images on a near side of the reference position, among the plurality of images, in one horizontal direction depending on their depth-direction positions with respect to the image at the reference position and shifting the images on a far side of the reference position, among the plurality of images, in the other horizontal direction depending on their depth-direction positions with respect to the image at the reference position to generate the plurality of images composing the group of left-eye images and performs the addition and averaging process for pixels for each pixel position to the plurality of images to generate the left-eye image, and 
     wherein the image generating unit performs the process of sequentially shifting the images on the near side of the reference position, among the plurality of images, in the other horizontal direction depending on their depth-direction positions with respect to the image at the reference position and shifting the images on the far side of the reference position, among the plurality of images, in the one horizontal direction depending on their depth-direction positions with respect to the image at the reference position to generate the plurality of images composing the group of right-eye images and performs the addition and averaging process for pixels for each pixel position to the plurality of images to generate the right-eye image. 
     (3) 
     The image processing apparatus according to (I), 
     wherein a relationship between the depth-direction positions and amounts of shift of the images is linearly set. 
     (4) 
     The image processing apparatus according to (1), 
     wherein the image generating unit performs hidden surface elimination when the addition and averaging process is performed to the respective groups of images. 
     (5) 
     The image processing apparatus according to (1), further comprising: 
     an image-quality adjusting unit that performs at least contrast adjustment to the respective images generated in the image generating unit. 
     (6) 
     The image processing apparatus according to (1), 
     wherein the plurality of images captured at varied positions in the depth direction is fluorescence microscope images. 
     (7) 
     An image processing method comprising: 
     a first step of performing a process of shifting a plurality of images captured at varied positions in a depth direction in opposite directions depending on their depth-direction positions with respect to the image at a reference position to generate a group of left-eye images and a group of right-eye images to which disparity is given; and 
     a second step of performing an addition and averaging process for pixels for each pixel position to the respective image groups generated in the first step to generate the left-eye image and the right-eye image. 
     REFERENCE SIGNS LIST 
       100 , 100 A A image processing apparatus 
       101 , 101 A image generating unit 
       102  amount-of-shift determining unit 
       103  image-quality adjusting unit