the following description is of the best - contemplated mode of carrying out the disclosure . this description is made for the purpose of illustrating the general principles of the disclosure and should not be taken in a limiting sense . the scope of the disclosure is best determined by reference to the appended claims . fig1 a is a schematic diagram of an image processing apparatus 100 according to an embodiment of the disclosure . fig1 b is a schematic diagram of an image capturing unit 110 according to an embodiment of the disclosure . the image processing apparatus 100 may comprise an image processing unit 120 and an image processing unit 120 . in an embodiment , the image capturing unit 110 is configured to retrieve raw images having information from different views simultaneously , and the captured raw images may have a first object and a second object located at different depths . the image processing unit 120 is configured to rearrange the raw images from the image capturing unit 110 to obtain multiple different - view sub - images . then , the image processing unit 120 may perform a refocusing process to at least one specific view sub - image of the different - view sub - images , thereby generating a refocused view image , and then output the refocused view image to a stereoscopic display device . the details of the aforementioned image processing procedure will be described later . for example , the image capturing unit 110 may be a plenoptic camera , which comprises a primary lens 112 , a lens array 114 , and an image sensor 116 . the lens array 114 may comprises multiple sub - lenses ( e . g . m * n sub - lens ), which are arranged in a direction perpendicular to a light axis 150 of the primary lens 112 , as illustrated in fig1 b . the image sensor 116 may comprise a plurality of light - sensitive pixels ( e . g . m * n light - sensitive pixels , wherein the amount of the sub - lenses may be different from that of the light - sensitive pixels ). alternatively , the image sensor 116 may comprise a plurality of sub - image sensors ( e . g . o * p sub - image sensors ), wherein each sub - image sensor has a plurality of light - sensitive pixels , and the amount of light - sensitive pixels of each sub - image sensor may be different . there is a corresponding region of light - sensitive pixels in the image sensor 116 to receive lights passing through each sub - lens in the lens array 114 . when lights from the scene to be captured pass through the primary lens 112 and the lens array 114 , images captured of different views will be emitted to the image sensor 116 , thereby obtaining a raw image having information from different views . fig1 c ˜ 1e are diagrams illustrating the procedure for obtaining different view sub - images from the raw image according to an embodiment of the disclosure . referring to fig1 a ˜ 1c , the image processing unit 120 may rearrange the raw image from the image capturing unit 110 to obtain multiple view sub - images , as illustrated in fig1 d and 1e . when retrieving a specific view sub - image from the raw image in fig1 c , pixels in the same location of each 2 × 2 block can be retrieved and combined into the specific view sub - image . for example , if pixels in the “ x ” location of each view sub - images in fig1 c are retrieved , the retrieved pixels can be combined into a side view sub - image , as illustrated in fig1 d . if pixels in the “•” location of each view sub - images in fig1 c are retrieved , the retrieved pixels can be combined into a center view sub - image , as illustrated in fig1 e . fig2 a and 2b are diagrams illustrating sampling images by using the image capturing unit 110 according to an embodiment of the disclosure . referring to fig1 a , 1 b and 2 a , when the image capturing unit 110 is used to capture an object a and an object b in a scene and the image capturing unit 110 focuses on the object a , a raw image having information from different views can be obtained . the raw image may be the image received by the image sensor 116 . the image processing unit 120 may rearrange the raw image from the image capturing unit 110 , thereby obtaining a view sub - image set comprising multiple sub - images , as illustrated in fig2 b . fig3 a ˜ 3e are diagrams illustrating the operations of a digital focusing process in the image processing unit 120 according to an embodiment of the disclosure . referring to both fig1 a and 3a , objects 301 , 302 and 303 are located in the object space 310 , and the objects 301 , 302 and 303 are located at different distances in front of the image capturing unit 110 . for example , lights from different views in the object space 310 may pass through the lens plane 320 and then be focused on the film plane , thereby forming an image on the film plane 330 . that is , after lights from different views in the scene ( i . e . object space 310 ) pass through the lens array 114 ( located between primary lens ( lens plane 320 ) and film plane 330 ), the lights may be received by the image sensor 116 ( i . e . image plane 330 ), thereby obtaining a raw image having information from different views . the raw image may be processed by the image processing unit 120 to obtain the view sub - images 340 , 350 and 360 , as illustrated in fig3 b , wherein the view sub - image 350 can be regarded as a center view image . it should be noted that since view sub - images 340 , 350 and 360 are images captured from different views in the object space 310 , the horizontal locations ( i . e . and / or vertical locations ) of the objects 301 ˜ 303 in the view sub - images 340 ˜ 360 may vary due to different view angles , as illustrated fig3 b . specifically , when the image processing unit 120 performs a digital focusing process on the view sub - images 340 ˜ 360 , the image processing unit 120 may overlap the view sub - images 340 and 350 together , thereby obtaining a refocused view image 370 , as illustrated in fig3 c . note that only the object 302 is completely overlapped in the refocused view image 370 in fig3 c . due to different view angles being used , the locations of the objects 301 and 303 in the view sub - images 340 and 350 may be different , respectively . further , the objects 301 ˜ 303 are located at different depths from the primary lens 112 . when one of the objects ( e . g . the object 302 ) is digitally refocused , only pixels having the same depth with the refocused object are clear . other pixels at different depths may be slightly blurred since the view sub - images from different views are overlapped . in addition , the image processing unit 120 may overlap the view sub - images 350 and 360 together to obtain a refocused image , or overlap all the view sub - images 340 ˜ 360 together to retrieve another refocused image ( not shown ). that is , the image processing unit 120 only focuses on the object 302 in the embodiment . the image processing unit 120 may further perform interpolation to different view sub - images to obtain refocused images or corresponding different view sub - images with an increased amount of pixels . in another embodiment , if the image processing unit 120 performs focusing on the object 303 , the image processing unit 120 may regard the view sub - image 350 as a reference image , and perform a shifting process to the view sub - image 340 in a horizontal direction and / or vertical direction relative to the view sub - image 350 , thereby completely overlapping the object 303 with both the view sub - images 340 and 350 to obtain a refocused view image 380 , as illustrated in fig3 d . similarly , the image processing unit 120 may also overlap the view sub - images 350 and 360 , or overlap all the view sub - images 340 ˜ 360 together to obtain another refocused view image ( not shown ). that is , the image processing unit 120 only focuses on the object 303 in the embodiment . the image processing unit 120 may further perform interpolation to different view sub - images to obtain refocused images or corresponding different view sub - images with an increased amount of pixels . in yet another embodiment , if the image processing unit 120 performs focusing on the object 301 , similar methods described in the aforementioned embodiments can be used . that is , the view sub - image 350 may be regarded as a reference image , and other view sub - images can be shifted relative to the view sub - image 350 , so that the object 301 is completely overlapped with each view sub - image to generate a refocused view image 390 , as illustrated in fig3 e . in the aforementioned embodiments of fig3 a ˜ 3e , it is appreciated that the refocusing process executed by the image processing unit 120 may be the image processing unit 120 performing a shifting and addition process to the view sub - images around a specific view sub - image to obtain the refocused view image . it should be noted that , the aforementioned shifting and addition process may regard an object ( e . g . the object 302 in fig3 b ) as a reference , and different view sub - images are shifted , so that the object is completely overlapped with each view sub - image . then , the portions other than the object ( e . g . objects 301 and 303 in fig3 b ) in each view sub - image are added , and thus the added portions may be slightly blurred . for example , the object 302 is regarded as a reference in fig3 c , and thus only the object 302 is clear in the refocused view image 370 . similarly , the object 303 is regarded as a reference in fig3 d , and thus only the object 303 is clear in the refocused view image 380 . the object 301 is regarded as a reference in fig3 e , and thus only the object 301 is clear in the refocused view image 390 . fig4 a ˜ 4c are diagrams illustrating stereoscopic displaying of the image processing unit 120 according to the first embodiment of the disclosure . referring to the embodiment of fig2 , when the image processing unit 120 outputs images to the stereoscopic display device , appropriate processes should be done to the different view images for stereoscopic displaying ( e . g . left view image and right view image ) in advance . for example , the image processing unit 120 may rearrange the raw image , which has information from different views , from the image capturing unit 110 to different view sub - images ( e . g . view sub - images 410 and 420 ). as illustrated in fig4 a , when the image processing unit 120 takes the view sub - image 410 as a reference image for calculating the right view image , the image processing unit 120 may set a region ( e . g . 4 × 3 different view sub - images up / down / left / right to the view sub - image 410 ), and perform a digital focusing process to the view sub - images in the region to generate the right view image . reference can be made to the embodiments of fig3 a ˜ 3e , for the details of the aforementioned procedure . similarly , when the image processing unit 120 is calculating the appropriate parallax required for a stereoscopic image , the view sub - image 420 can be taken as a reference image for calculating the left view image . meanwhile , the image processing unit 120 may set another region ( e . g . 4 × 3 different view sub - images left / right to the view sub - images 420 ), and perform a digital focusing process to the view sub - images in the region to generate the left view image . reference can be made to the embodiments of fig3 a ˜ 3e , for the details of the digital focusing process . in addition , the image processing unit 120 may receive an external control signal ( e . g . from the stereoscopic display device , the image capturing device , or other devices , such as a personal computer ) for refocusing on an object at different depths . for example , the image capturing unit 110 may focus on the object a in the beginning , and thus the left view image 440 and the right view image 430 to be generated by the image processing unit 120 may focus on the object a , as illustrated in fig4 b . when the image processing unit 120 receives an external control signal to perform a digital refocusing process , the output left view image 460 and the right view image 450 may refocus on the object b , as illustrated in fig4 c . fig5 is a diagram illustrating the image enlarging process of the raw image having information from different views according to the second embodiment of the disclosure . the differences between the embodiment in fig5 and that of fig4 a ˜ 4c may be that the raw image in fig5 may be pre - processed by the image processing unit 120 , such as performing a scaling process to the raw image , so that the amount of pixels in the scaled raw image may become larger or smaller in comparison with that of the raw image before the scaling process . thus , the resolution of the generated left view image and the right view image may match the required input image resolution of the stereoscopic display device , wherein well - known image scaling techniques ( e . g . bilinear interpolation or bi - cubic interpolation ) can be used in the aforementioned scaling process to perform pixel interpolation or extrapolation . for example , as illustrated in fig5 , the image processing unit 120 may enlarge the view sub - image set 510 in the horizontal direction and vertical direction by 1 . 67 times that of the height and width of each view sub - image to generate an enlarged image 520 . given that there are 3 × 3 pixels in the image sub - set 512 of the view sub - image set 510 , the image sub - set 522 in the corresponding location of the enlarged image 520 may comprise 5 × 5 pixels . it should be noted that the aforementioned embodiment merely describes the enlarging process of an image sub - set in the corresponding location . for those skilled in the art , it is appreciated that the aforementioned enlarging process can be also applied to other image sub - sets at other corresponding locations , and the image enlarging ratio can be adjusted freely . subsequently , the image processing unit 120 may select a respective view sub - image ( e . g . view sub - images 530 and 540 ) from the enlarged image 520 as a reference image for the left view image and the right view image , and perform a digital focusing process to the different view sub - images within a region of the two reference images , thereby generating the refocused left view image and the refocused right view image . reference can be made to the embodiments of fig3 a ˜ 3e , for the details of the digital focusing process . in the embodiment , after the image processing unit 120 enlarges the view sub - image set 510 in the horizontal direction and vertical direction by 1 . 67 times that of the width and height of each view sub - image to generate the enlarged image 520 , the image processing unit 120 may further covert the enlarged image 520 into a corresponding format based on the display requirement of the stereoscopic display device ( e . g . multi view sub - images in three views or more , such as the view sub - images 530 ˜ 550 , and the corresponding image format ). then , the image processing unit 120 may perform the digital refocusing process to the converted enlarged image according to the received external control signal , and output multiple view images generated by the digital refocusing process to the stereoscopic display device . fig6 a ˜ 6c are diagrams illustrating stereoscopic displaying of the image processing unit according to the third embodiment of the disclosure . referring to fig2 and 6 a ˜ 6 c , for example , the image processing unit 120 may determine the view sub - images 620 and 610 from the view sub - image set 600 as reference images for the left view image and the right view image , respectively , as illustrated in fig6 a . then , the image processing unit 120 may perform a digital focusing process to the view sub - images within the regions 625 and 615 to generate the left view image 640 and the right view image 630 ( i . e . the refocused view images ), as illustrated in fig6 b . however , it is possible that the resolution of the left view image 640 and the right view image 630 does not match the resolution requirement of the stereoscopic display device , and thus the image processing unit 120 may further perform a scaling process on the left view image 640 and the right view image 630 ( e . g . enlarging the left / right view images in the horizontal direction and vertical direction for 1 . 5 times ), thereby generating a left view image 660 and right view image 650 which having a resolution matching with the requirement of the stereoscopic display device , as illustrated in fig6 c . then , the image processing unit 120 may output the left view image 660 and the right view image 650 to the stereoscopic display device . it should be noted that the image capturing unit 110 focuses on the object a in the beginning . after the image processing unit 120 has received an external control signal ( e . g . from the stereoscopic display device ), the image processing unit 120 may adjust the output left / right view images for focusing on the object b . fig7 is a flow chart illustrating the image refocusing method according to an embodiment of the disclosure . in step s 700 , the image capturing unit 110 may receive lights from a scene , and output a raw image having information from different views . for example , the lights from the scenes may pass through the primary lens 112 and the lens array of the image capturing unit 110 , and form the raw image on the image sensor 116 . in step s 710 , the image processing unit 120 may rearrange the raw image from the image capturing unit 110 to obtain multiple different view sub - images . in step s 720 , the image processing unit 120 may perform a digital refocusing process to at least one specific view sub - image having a specific view corresponding to the multiple different view sub - images to generate multiple refocused view images . in step s 730 , the image processing unit 120 may output the multiple refocused view images to a stereoscopic display device . it should be noted that the aforementioned embodiments in fig5 and 6 a ˜ 6 c can be combined into the method described in fig7 . for example , as described in the embodiment of fig5 , after step s 710 , the image processing unit 120 may perform a scaling process on the different view sub - images to generate enlarged images which match the resolution requirement of the stereoscopic display device . then , the image processing unit 120 may determine a reference image for the left view image and the right view image from the enlarged image , respectively . the image processing unit 120 may perform a digital focusing process to the different view sub - images within a predetermined range to generate the refocused left view image and the refocused view right image . in addition , in the aforementioned embodiment , after the image processing unit 120 performs the scaling process to the different view sub - images , the image processing unit 120 may further convert the enlarged images to match the requirement of the stereoscopic display device ( e . g . view sub - images in three views or more , and a corresponding image format ), and then perform a digital refocusing process to the converted enlarged images . that is , the image processing unit 120 may generate a specific amount of different view sub - images and a corresponding image format required in the stereoscopic display device by using the enlarged different view sub - images . further , as described in the embodiments of fig6 a ˜ 6c , it is possible that the generated refocused view images do not match the resolution requirement of the stereoscopic display device . accordingly , the image processing unit 120 may perform a scaling process on the refocused view images to generate a left view image and a right view image that matches the resolution requirement of the stereoscopic display device . while the disclosure has been described by way of example and in terms of the preferred embodiments , it is to be understood that the disclosure is not limited to the disclosed embodiments . to the contrary , it is intended to cover various modifications and similar arrangements ( as would be apparent to those skilled in the art ). therefore , the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements .