JP2007306406A - Image processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor which obtains a relatively satisfactory image from a close range to a long range with a two focus lens in which a distance is fixed up to an imaging area. <P>SOLUTION: The image processor comprises: a two focus lens 21 obtained by combining first and second lenses 22, 23 with different focal lengths; an imaging device 24 for generating a first image showing a composite image from both of the first and second lenses 22, 23, and a second image showing an image from one of either the first lens 22 or the second lens 23; a convolution part 33 for executing convolution operation of the first image and an inverse function of a blurring function of either one of the first lens 22 or the second lens 23; a subtractor 36 for subtracting the second image from the first image, and for calculating a fourth image showing an image from the other of either the first lens 22 or the second lens 23; and a comparison determination part 38 for determining whether the second image or the fourth image is focused. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an image processing apparatus capable of capturing an image by a bifocal lens with a fixed distance to an imaging surface and obtaining a relatively good image from a short distance to a long distance.

  As shown in FIG. 14, the conventional image processing apparatus includes an imaging unit 5 that generates an image, an image processing unit 9 that performs image processing of the image, and a display unit 10 that displays an image.

The imaging unit 5 includes a bifocal lens 11 in which a lens 12 and a lens 13 having different focal lengths are combined, and an imaging element 14 that captures an image by the bifocal lens 11. On the other hand, the image processing unit 9 stores the image from the imaging unit 5 and the inverse of the blur function of one of the two lenses 12 and 13 constituting the bifocal lens 11. A coefficient storage unit 8 that stores function coefficients and a convolution unit 7 that performs a convolution operation on the image are included (see, for example, Patent Document 1).
JP 2003-309723 A

  However, in the conventional image processing apparatus disclosed in Patent Document 1, the image formed on the imaging surface of the imaging element 14 is a composite image by the two lenses 12 and 13, and from which the composite image is shown, It was necessary to select whether to remove the blur component due to the lens. Further, when the convolution operation is performed on the image assuming a distance different from the actual distance to the subject, there is a problem that the sharpness is inferior to the image captured by only one of the lenses.

  The present invention has been made to solve the conventional problems, and an image processing apparatus capable of obtaining a relatively good image from a short distance to a long distance with a bifocal lens having a fixed distance to an imaging surface. The purpose is to provide.

  The image processing apparatus of the present invention includes a bifocal lens composed of first and second lenses having different focal lengths and concentrically combined with the optical axes of the first and second lenses, and the two focal points. A first image in which a distance from the lens is fixed and a composite image by both the first and second lenses is shown; and a second image in which an image by any one of the first and second lenses is shown A convolution operation of an inverse function of the blur function of one of the first image and the first and second lenses, and the execution result of the convolution operation is output as a third image A convolution unit that performs subtraction, a subtraction unit that subtracts the second image from the first image, and calculates a fourth image in which an image of one of the first and second lenses is displayed, and the second to second A comparison / determination unit for determining which of the four images is in focus; It has a configuration comprising.

  With this configuration, a relatively good image can be output for any subject from a short distance to a long distance.

  In the image processing apparatus of the present invention, the comparison / determination unit calculates the intensity of the high-frequency component of at least one specific area of each of the second to fourth images, and the specific area of each of the second to fourth images. A focused image is selected from the second to fourth images based on the intensity of the high-frequency component.

  With this configuration, it is possible to accurately select an image focused on the subject.

  In the image processing apparatus of the present invention, the comparison / determination unit adds a weight to the intensity of the high-frequency component in the specific region of each of the second to fourth images.

  With this configuration, it is possible to accurately select an image focused on the subject.

  In the image processing apparatus of the present invention, the weight of the specific area defined in the central portion of the third image is greater than the weight of the specific area defined in the central portions of the second and fourth images. Have.

  With this configuration, it can be accurately determined whether or not a medium-distance subject has been imaged.

  In the image processing apparatus of the present invention, the weight of the specific area in the upper peripheral portion of the second or fourth image is larger than the weight of the specific area in the upper peripheral portion of the other image, and the specific area in the lower peripheral portion. Has a configuration smaller than the weight of the specific area in the lower peripheral portion of the other image.

  With this configuration, it is possible to accurately determine whether a short-distance subject and a long-distance subject have been imaged.

  In the image processing apparatus of the present invention, the comparison / determination unit divides each of the second to fourth images into a plurality of partial images, and based on the intensity of the high-frequency component of the partial images of the second to fourth images. A partial image in focus is selected, and one focused image is generated from the selected partial image.

  With this configuration, even when a plurality of subjects having different distances are imaged, it is possible to output a relatively good image in which each subject is in focus.

  In the image processing apparatus of the present invention, each of the partial images of the second to fourth images has an overlapping area overlapping with an adjacent partial image, and the comparison / determination unit is configured to focus on the selected partial image. When one matching image is generated, a weight is added to the overlapping region, and the overlapping region to which the weight is added is overlapped.

  With this configuration, it is possible to output a relatively good image up to a portion where the divided images overlap.

  In the image processing apparatus according to the aspect of the invention, the convolution unit may perform a convolution operation of an inverse function of the other blur function of the first image and the first and second lenses as a fifth image. It has a configuration to output.

  With this configuration, a relatively good image can be output for any subject from a short distance to a long distance.

  In the image processing apparatus of the present invention, the comparison / determination unit calculates the intensity of the high frequency component of at least one specific region of each of the second to fifth images, and the specific region of each of the second to fifth images. The in-focus image is selected from the second to fifth images based on the intensity of the high-frequency component extracted from the image.

  With this configuration, it is possible to accurately select an image focused on the subject.

  In the image processing apparatus of the present invention, the comparison / determination unit adds a weight to the high-frequency component of each of the second to fifth images.

  With this configuration, it is possible to accurately select an image focused on the subject.

  In the image processing apparatus according to the aspect of the invention, the weight of the specific area defined in the central portion of the third and fifth images may be greater than the weight of the specific area defined in the central portion of the second and fourth images. It has a large configuration.

  With this configuration, it can be accurately determined whether or not a medium-distance subject has been imaged.

  In the image processing apparatus of the present invention, the weight of the specific area in the upper peripheral portion of the second or fourth image is larger than the weight of the specific area in the upper peripheral portion of the other image, and the specific area in the lower peripheral portion. Has a configuration smaller than the weight of the specific area in the lower peripheral portion of the other image.

  With this configuration, it is possible to accurately determine whether a short-distance subject and a long-distance subject are included.

  In the image processing apparatus of the present invention, the comparison / determination unit divides each of the second to fifth images into a plurality of partial images, and based on the intensity of the high-frequency component of the partial images of the second to fifth images. A partial image in focus is selected, and one focused image is generated from the selected partial image.

  With this configuration, even when a plurality of subjects having different distances are imaged, it is possible to output a relatively good image in which each subject is in focus.

  In the image processing apparatus of the present invention, each of the partial images of the second to fifth images has an overlapping area overlapping with an adjacent partial image, and the comparison / determination unit is configured to focus on the selected partial image. When one matching image is generated, a weight is added to the overlapping region, and the overlapping region to which the weight is added is overlapped.

  With this configuration, it is possible to output a relatively good image up to a portion where the divided images overlap.

  The present invention is composed of first and second lenses having different focal lengths, and the distance between the bifocal lens and the bifocal lens fixed by concentrically combining the optical axes of the first and second lenses is fixed. An imaging device for generating a first image showing a composite image by both the first and second lenses and a second image showing an image by either one of the first and second lenses; A convolution unit that executes a convolution operation of an inverse function of one image and the blur function of one of the first and second lenses, and outputs a result of the convolution operation as a third image; Subtracting two images and calculating a fourth image showing an image by one of the first and second lenses, and determining whether any of the second to fourth images is in focus And a comparison / determination unit that does not have a mechanical focus adjustment mechanism. In which it is possible to obtain a relatively good image from the distance to the long distance.

  Hereinafter, an image processing apparatus according to an embodiment of the present invention will be described with reference to the drawings.

(First embodiment)
As shown in FIG. 1, the image processing apparatus according to the present embodiment includes an imaging unit 20 that generates an image of a subject, an image processing unit 30 that performs image processing on the image, and a display that displays the image processed image. Part 40.

  The imaging unit 20 includes a bifocal lens 21 (see FIG. 3) including first and second lenses 22 and 23 having different focal lengths, and a distance to the bifocal lens 21 is fixed, and the first and second lenses 22, An image sensor 24 for generating a first image showing a composite image by both of the image sensors 23 and a second image showing an image by any one of the first and second lenses 22 and 23, and the first lens 22. And a light shielding plate 25 having an opening smaller than the diameter.

  The image processing unit 30 includes a first storage unit 31 that stores the first image, a second storage unit 35 that stores the second image, and the first image and any one of the first and second lenses 22 and 23. A convolution unit 33 that performs a convolution operation of the inverse function of the blur function and outputs the execution result of the convolution operation as a third image, a third storage unit 34 that stores the third image, and a first image from the first image A second subtracting unit 36 for subtracting two images and calculating a fourth image showing an image of one of the first and second lenses 22 and 23; a fourth storage unit 37 for storing the fourth image; A comparison / determination unit 28 that determines which of the second to fourth images is in focus is provided.

  As shown in FIG. 3, the bifocal lens 21 is concentrically combined with the optical axes of the first and second lenses 22 and 23 matched.

  When the light shielding plate 25 is not disposed between the bifocal lens 21 and the image sensor 24, a composite image by both the first and second lenses 22 and 23 is formed on the imaging surface 3 as shown in FIG. When the light shielding plate 25 is disposed between the bifocal lens 21 and the imaging element 24, an image by the first lens 22 is formed on the imaging surface 3 as shown in FIG.

  Further, in the composite image by both the first and second lenses 22 and 23, as shown in FIG. 6, when the blurred image b spreads around the focused point image a, and as shown in FIG. There is a case where the blurred image d spreads in a ring shape in a place away from the focused point image c.

  In order to correct such a blurred image, the convolution unit 33 is one of the first image and the first and second lenses 22 and 23 in which the composite image by both the first and second lenses 22 and 23 is shown. The convolution operation of the inverse function of one of the blur functions is executed, and the execution result of the convolution operation is output as a third image.

  The blur function is a function indicating scattering on the imaging surface of a point light source placed on the optical axis, and is also called a point spread function.

  Further, as shown in FIG. 8, the second to fourth images have specific areas 51a to 51e in which weights for high frequency components are defined.

  The comparison / determination unit 28 determines the intensity of the high frequency components of the specific areas 51a to 51e of the second image from the second storage unit 35 and the intensity of the high frequency components of the specific areas 51a to 51e of the third image from the third storage unit 34. And the intensity of the high-frequency component in the specific areas 51a to 51e of the fourth image from the fourth storage unit 37, and the second image is utilized using the feature that the focused image contains a lot of high-frequency components. One of the fourth to fourth images is selected as the focused image. In addition, the comparison / determination unit 28 adds weights to the intensities of the high frequency components of the second to fourth images.

  Next, the weight added to the intensity of the high frequency component of each of the second to fourth images will be described with reference to FIG.

  As shown in FIG. 9B, in the third image focused on the medium-distance subject (such as a person) 53, the weight of the specific area 56c defined in the central portion is the central portion of the second and fourth images. It is larger than the weight of the specific areas 57c and 55c defined in. On the other hand, in the second image focused on a long-distance subject (landscape or the like) 52, as shown in FIG. 9A, the weights of the specific areas 57a and 57b defined in the upper peripheral portion are It is larger than the weights of the specific areas 55a and 55b defined in the upper peripheral part and the specific areas 56a and 56b defined in the upper peripheral part of the fourth image.

  Further, in the fourth image focused on the subject 54 at a short distance, as shown in FIG. 9C, the weights of the specific areas 55d and 55e defined in the lower peripheral portion are the lower periphery of the second image. It is larger than the weights of the specific areas 57d and 57e defined in the part and the specific areas 56d and 56e defined in the lower peripheral part of the fourth image.

  The comparison / determination unit 28 can execute the determination with higher accuracy by defining the weight added to the intensity of the high-frequency component in the specific area of each of the second to fourth images in this way.

  Further, the comparison / determination unit 28 divides each of the second to fourth images into a plurality of partial images, determines whether each portion is in focus, and determines one image from the focused partial images. You may make it synthesize | combine.

  Next, with reference to FIGS. 10 to 13, a method of determining whether or not each part is in focus and synthesizing one image from the focused partial images will be described.

  Long-distance subjects (mountains and trees in this embodiment) 60, 61, medium-distance subjects (guide plates in this embodiment) 63, and relatively short-distance subjects (people in this embodiment) 62 are imaged. The operation of the comparison / determination unit 28 will be described.

  The subject as shown in FIG. 10 includes a long-distance mountain 60, a long-distance tree 61, a relatively short-distance person 62, and a medium-distance guide plate 63.

  The image of only the second lens 23 of the bifocal lens 21 shown in FIG. 11A is focused on the distant mountain 60 and the tree 61, and the image of the bifocal lens 21 shown in FIG. The image of only the first lens 22 is focused on the person 62 at a relatively short distance. On the other hand, the third image obtained from the convolution operation of the first image and the inverse function of one of the first and second lenses 22 and 23 is an intermediate distance as shown in FIG. The guide plate 63 is in focus most.

  Each of these images is divided into, for example, 16 partial images, a focused region is selected as shown in FIG. 12, and one image is synthesized from the selected partial images.

  At this time, the boundary interpolation is executed as shown in FIG. 13 so that the boundary between the partial images is not conspicuous. For example, the image is divided so that the boundary between the partial image 70 and the adjacent partial image 71 overlaps, and interpolation of the component of the partial image 70 and the component of the partial image 71 is executed at the overlapping portion 72.

  Further, if the mixing ratio is changed depending on the position, the boundary portion can be made inconspicuous. Note that the number of divisions and the division position are not limited to this example, and the boundary interpolation method is not particularly limited.

  Next, the operation of the imaging unit 20 of the image processing apparatus according to the present embodiment will be described.

  A first image showing a composite image by both the first and second lenses 22 and 23 in a state where the light shielding plate 25 is not inserted between the bifocal lens 21 and the image sensor 24 when the image is picked up toward the subject. And a second image showing an image by the first lens 22 in a state in which the light shielding plate 25 is inserted between the bifocal lens 21 and the image pickup device 24, and the first and second images are subjected to image processing. Is output to the unit 30.

  Next, the operation of the image processing unit 30 of the image processing apparatus according to the present embodiment will be described.

  When a subject is photographed via the bifocal lens 21, a first image showing a composite image by both the first and second lenses 22 and 23 is stored in the first storage unit 31, and only the first lens 22 is stored. The second image showing the image is stored in the second storage unit 35.

  The ratio of the brightness of the second image by the first lens 22 to the brightness of the first image by the entire bifocal lens 21 is substantially the same as the ratio of the area of the first lens 22 to the area of the entire bifocal lens 21. In consideration of the above, the brightness of the second image output to the comparison determination unit 28 is corrected.

  In the convolution unit 33, a convolution operation is performed on the coefficient of the inverse function of the blur function of the first lens 22 from the coefficient storage unit 32 and the first image from the first storage unit 31, and the result of the convolution operation is obtained. The third image is stored in the third storage unit 34.

  On the other hand, the second image is subtracted from the first image, and a fourth image showing an image by only the second lens 23 is calculated by the subtracting unit 36 and stored in the fourth storage unit 37.

  The ratio of the brightness of the fourth image by the second lens 23 to the brightness of the first image by the entire bifocal lens 21 is substantially the same as the ratio of the area of the second lens 23 to the area of the entire bifocal lens 21. In consideration of the fact, the brightness of the fourth image output to the comparison determination unit 28 is corrected.

  Next, the most in-focus image among the second to fourth images is selected by the comparison determination unit 28 and displayed on the display unit 40.

  Next, the operation of the comparison / determination unit 28 of the image processing apparatus according to the present embodiment will be described.

  In the comparison determination unit 28, the intensity of the high-frequency component in the specific region (see FIG. 8) of the second image from the second storage unit 35 and the specific region (see FIG. 8) of the third image from the third storage unit 34. The intensity of the high frequency component and the intensity of the high frequency component in the specific area (see FIG. 8) of the fourth image from the fourth storage unit 37 are calculated. Next, an image that is in focus is selected using the feature that an image that is in focus contains more high-frequency components than an image that is out of focus.

  As described above, according to the image processing apparatus of the present embodiment, the first and second lenses having different focal lengths are combined concentrically with the optical axes of the first and second lenses being matched. The distance between the bifocal lens and the bifocal lens is fixed, and a first image showing a composite image by both the first and second lenses and an image by either one of the first and second lenses are shown. An image sensor for generating the second image, a convolution operation of an inverse function of the first image and the blur function of one of the first and second lenses, and a result of the convolution operation as a third result. A convolution unit that outputs as an image, a subtraction unit that subtracts the second image from the first image, and calculates a fourth image showing an image of one of the first and second lenses, and second to second A comparison / determination unit that determines which of the four images is in focus. And it makes it possible to output a relatively good image for any object from short range to long range.

  Further, in the image processing apparatus according to the present embodiment, the comparison / determination unit adds a weight to the high-frequency component extracted from the specific area of each of the second to fourth images, and based on the intensity of the high-frequency component to which the weight is added. Thus, by selecting one of the second to fourth images as the focused image, it is possible to accurately select the image focused on the subject.

  In the image processing apparatus according to the present embodiment, the weight of the specific area defined in the central portion of the third image is larger than the weight of the specific area defined in the central portion of the second and fourth images. It is possible to accurately determine whether or not a medium-distance subject has been imaged.

  In addition, the image processing apparatus according to the present embodiment is configured such that the weight of the specific area in the upper peripheral portion of the second or fourth image is larger than the weight of the specific region in the upper peripheral portion of the other image, and the lower peripheral portion is specified. Since the weight of the area is smaller than the weight of the specific area in the lower peripheral part of the other image, it is possible to accurately determine whether or not a short-distance subject and a long-distance subject have been imaged.

  In the image processing apparatus according to the present embodiment, the comparison / determination unit divides each of the second to fourth images into a plurality of partial images, and based on the intensity of the high-frequency component of the partial images of the second to fourth images. By selecting a partial image that is in focus and generating a single focused image from the selected partial image, even if multiple subjects with different distances are captured, each subject is in focus A good image can be output.

  In the image processing apparatus according to the present embodiment, when the comparison / determination unit generates one focused image from the selected partial image, the overlap region is added with a weight, and the overlap region with the weight is added. By overlapping the images, it is possible to output a relatively good image up to the overlapping portion of the divided images.

(Second Embodiment)
The configuration of the image processing apparatus according to the second embodiment of the present invention will be described with reference to FIG.

  As shown in FIG. 2, the image processing apparatus includes an imaging unit 20 and an image processing unit 30.

  The image processing apparatus according to the present embodiment includes an imaging unit 20 that generates an image of a subject, an image processing unit 30 that performs image processing on the image, and a display unit 40 that displays the image processed image. .

  The imaging unit 20 includes first and second lenses 22 and 23 having different focal lengths, and a bifocal lens 21 that is combined concentrically with the optical axes of the first and second lenses 22 and 23 being matched. A first image in which the distance from the bifocal lens is fixed and a composite image by both the first and second lenses 22 and 23 is shown, and an image by one of the first and second lenses 22 and 23 is shown. The image sensor 24 for generating the second image and the light shielding plate 25 having an opening smaller than the aperture of the first lens 22 are included.

  On the other hand, the image processing unit 30 is one of the first storage unit 31 that stores the first image, the second storage unit 35 that stores the second image, and the first image and the first and second lenses 22 and 23. A convolution unit 33 that executes a convolution operation of the inverse function of one of the blur functions and outputs the execution result of the convolution operation as a third image, and a third storage unit 34 that stores the third image are provided. .

  The convolution unit 33 executes a convolution operation of the inverse function of the first image and the other blur function of the first and second lenses 22 and 23, and outputs the execution result of the convolution operation as a fifth image. It is like that.

  The image processing unit 30 further includes a fifth storage unit 39 for storing the fifth image, and subtracts the second image from the first image, so that an image by one of the first and second lenses 22 and 23 is shown. A subtractor 36 for calculating the fourth image, a fourth storage 37 for storing the fourth image, and a comparison / determination unit 38 for determining which of the second to fifth images is in focus. I have.

  Next, the operation of the image processing unit of the image processing apparatus according to the second embodiment will be described.

  When a subject is photographed through the bifocal lens 21, a first image showing images by both the first and second lenses 22 and 23 is stored in the first storage unit 31, and only by the first lens 22. The second image showing the image is stored in the second storage unit 35. On the other hand, the second image is subtracted from the first image, and a fourth image showing an image by only the second lens 23 is calculated by the subtracting unit 36 and stored in the fourth storage unit 37.

  Further, the convolution unit 33 performs a convolution operation between the inverse function of the blur function of the first lens 22 and the first image, and a convolution operation of the inverse function of the blur function of the second lens 23 and the first image. Then, the result of the convolution operation is stored in the third storage unit 34 and the fifth storage unit 39.

  Next, the most focused image is selected from the second to fifth storage units 34, 35, 37, and 39.

  Note that it is not necessary for each of the five storage units (first to fifth storage units 31, 34, 35, 37, and 39) to have a capacity sufficient to store image data for one screen.

  As described above, the image processing apparatus according to the present embodiment is composed of the first and second lenses having different focal lengths, and is combined in a concentric manner by matching the optical axes of the first and second lenses. A distance between the focal lens and the bifocal lens is fixed, and a first image showing a composite image by both the first and second lenses and an image by one of the first and second lenses are shown. An image sensor that generates a second image, a convolution operation of the inverse function of the blur function of one of the first image and the first and second lenses, and a result of the convolution operation as a third image A convolution unit for outputting, a subtraction unit for subtracting the second image from the first image, and calculating a fourth image showing an image by one of the first and second lenses, and the second to fourth images And a comparison / determination unit that determines whether one of the two is in focus. However, since the convolution operation of the inverse function of the other blur function of the first image and the first lens and the second lens is executed and output as the fifth image, any object from a short distance to a long distance can be obtained. However, a relatively good image can be output.

  In the image processing apparatus according to the present embodiment, the comparison / determination unit adds a weight to the high-frequency component extracted from each specific region of the second to fifth images, and the first determination is based on the intensity of the high-frequency component to which the weight is added. Since one of the second to fifth images is selected as the focused image, the image focused on the subject can be accurately selected.

  In the image processing apparatus according to the present embodiment, the comparison / determination unit divides each of the second to fifth images into a plurality of partial images, and adjusts the focus based on the intensity of the high-frequency component of the second to fifth image partial images. Since a matching partial image is selected, and one focused image is generated from the selected partial image, even if a plurality of subjects with different distances are captured, each subject is relatively in focus. An image can be output.

  As described above, the image processing apparatus according to the present invention has an effect that a relatively good image can be obtained from a short distance to a long distance with a bifocal lens in which the distance to the imaging surface is fixed. It is useful as a portable terminal or ultra-small digital still camera.

1 is a block diagram showing a configuration of an image processing apparatus according to a first embodiment of the present invention. The block diagram in which the structure of the image processing apparatus which concerns on the 2nd Embodiment of this invention was shown Sectional drawing and front view of the bifocal lens of the image processing apparatus which concerns on the 1st and 2nd embodiment of this invention The figure which showed typically the image pick-up part when the light-shielding plate is not arrange | positioned between a bifocal lens and an image pick-up element. The figure which showed typically the image pick-up part when the light-shielding plate is arrange | positioned between a bifocal lens and an image pick-up element. A diagram schematically showing a blurred image spreading around a focused point image A diagram that schematically shows a blurred image spreading in a ring shape at a location away from the focused point image The figure which showed typically the specific area | region of the image produced | generated by the image processing apparatus which concerns on the 1st and 2nd embodiment of this invention. The figure which showed typically the difference in the weight of the specific area | region of the image produced | generated by the image processing apparatus which concerns on the 1st and 2nd embodiment of this invention. The figure by which an example of the image produced | generated by the image processing apparatus which concerns on the 1st and 2nd embodiment of this invention was shown (A) A diagram schematically showing a portion focused on a long-distance subject, (B) a diagram schematically showing a portion focused on a medium-distance subject, (A) near A diagram schematically showing the part in focus on the subject at a distance (A) A diagram schematically showing an image cut out only in a portion focused on a long-distance subject, and (B) a diagram schematically showing an image cut out only in a portion focused on a medium-distance subject. (C) A diagram schematically showing an image obtained by cutting out only a portion focused on a short-distance subject. The figure which showed typically the interpolation method of the partial image in the image processing apparatus which concerns on the 1st and 2nd embodiment of this invention. Block diagram showing the configuration of a conventional image processing apparatus

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 The light trace when a parallel ray injects into the peripheral part of a bifocal lens 2 The light trace when a parallel ray injects into the center part of a bifocal lens 3 Imaging surface 4 Optical axis of a bifocal lens 20 Imaging part 21 Two focus Lens 22 First lens 23 Second lens 24 Image sensor 25 Light shielding plate 28 Comparison determination unit 30 Image processing unit 31 First storage unit 32 Coefficient storage unit 33 Convolution unit 34 Third storage unit 35 Second storage unit 36 Subtraction unit 37 Fourth storage unit 38 Comparison determination unit 39 Fifth storage unit 40 Display unit 50 Image 51a, 51b, 51c, 51d, 51e Specific area 52 Long-distance subject 53 Medium-distance subject 54 Short-distance subject 55a, 55b Small weight Specific areas 56a, 56b, 56c, 56d Weighted specific areas 57a, 57b Weighted specific areas 60 Distant subject 61 Distant subject Body 62 Subject in relatively short distance 63 Subject in medium distance 64 Unselected area 70 Partial image 71 Partial image 72 Area to be interpolated

Claims (14)

A bifocal lens composed of first and second lenses having different focal lengths and concentrically combined with the optical axes of the first and second lenses matched;
A first image in which a distance from the bifocal lens is fixed, a composite image by both the first and second lenses is shown, and an image by any one of the first and second lenses is shown. An image sensor for generating two images;
A convolution unit that performs a convolution operation of an inverse function of the blur function of one of the first image and the first and second lenses, and outputs a result of the convolution operation as a third image;
A subtractor that subtracts a second image from the first image and calculates a fourth image showing an image of the first lens and the second lens that is not used to generate the second image;
An image processing apparatus comprising: a comparison determination unit configured to determine which of the second to fourth images is in focus. The comparison determination unit calculates an intensity of a high frequency component of at least one specific area of each of the second to fourth images, and based on the intensity of the high frequency component of the specific area of each of the second to fourth images. The image processing apparatus according to claim 1, wherein an in-focus image is selected from the second to fourth images. The image processing apparatus according to claim 2, wherein the comparison determination unit adds a weight to the intensity of the high-frequency component in the specific area of each of the second to fourth images. 4. The image according to claim 3, wherein the weight of the specific area defined in the center of the third image is larger than the weight of the specific area defined in the center of the second and fourth images. Processing equipment. The weight of the specific area in the upper peripheral part of the second or fourth image is larger than the weight of the specific area in the upper peripheral part of the other image, and the weight of the specific area in the lower peripheral part is lower than the other image. The image processing apparatus according to claim 3, wherein the image processing apparatus is smaller than a weight of the specific area in the side peripheral portion. The comparison / determination unit divides each of the second to fourth images into a plurality of partial images, and selects a focused partial image based on the intensity of the high-frequency component of the partial images of the second to fourth images. The image processing apparatus according to claim 1, wherein one image in focus is generated from the selected partial image. Each partial image of the second to fourth images has an overlapping area overlapping with an adjacent partial image,
The comparison / determination unit adds a weight to the overlap region and overlaps the overlap region to which the weight is added when generating one focused image from the selected partial image. Item 7. The image processing apparatus according to Item 6. The convolution unit performs a convolution operation of an inverse function of the blur function of the other of the first image and the first and second lenses, and outputs the result as a fifth image. An image processing apparatus according to 1. The comparison determination unit calculates the intensity of the high frequency component of at least one specific region for each of the second to fifth images, and based on the intensity of the high frequency component of the specific region of each of the second to fifth images. 9. The image processing apparatus according to claim 8, wherein an in-focus image is selected from the second to fifth images. The image processing apparatus according to claim 9, wherein the comparison determination unit adds a weight to the intensity of the high-frequency component in the specific area of each of the second to fifth images. The weight of the specific area defined in the central part of the third and fifth images is larger than the weight of the specific area defined in the central part of the second and fourth images. The image processing apparatus described. The weight of the specific area in the upper peripheral part of the second or fourth image is larger than the weight of the specific area in the upper peripheral part of the other image, and the weight of the specific area in the lower peripheral part is lower than the other image. The image processing apparatus according to claim 10, wherein the image processing apparatus is smaller than a weight of the specific region in the side peripheral portion. The comparison / determination unit divides each of the second to fifth images into a plurality of partial images, and selects a focused partial image based on the high-frequency component intensity of the partial images of the second to fifth images. The image processing apparatus according to claim 8, wherein one image in focus is generated from the selected partial image. Each of the partial images of the second to fifth images has an overlapping area overlapping with an adjacent partial image,
The comparison / determination unit adds a weight to the overlap region and overlaps the overlap region to which the weight is added when generating one focused image from the selected partial image. Item 14. The image processing apparatus according to Item 13.

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