JP2001086332A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce image correction processing time or an image correction data amount and to efficiently execute image correction by considering the symmetry of the deterioration degree of images, related to the center point or center line of an image areas and correcting the entire image from the correction amount of a part of the image at correction of the image. SOLUTION: Shading is provided with a feature of almost line symmetry around a center line X3 and a center line Y3 of an image area and almost point symmetry about the center point O3. Thus, by using the symmetry, a correction operation is performed for respective pixels for the 1/4 area A3E3O3F3 of the area A3B3C3D3 of the entire image, and a correction amount is obtained. Also, correction data composed of the correction amount of the area A3E3O3F3 are prepared in advance are and held in a storage part, the correction data are called as needed and the correction amount is obtained. Then, by conducting image correction of the other area, the area E3B3G3O3 to be line symmetrical to the center line Y3 with the area A3E3O3F3 for instance, by using the correction amount, the image correction of the entire image is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for correcting image quality deterioration of an image caused by an optical system including a photographing lens for photographing an image and an image forming lens of an image reading apparatus. The present invention belongs to the technical field of an image processing apparatus capable of efficiently performing image correction by reducing time and the amount of image correction data.

[0002]

2. Description of the Related Art At present, an image photographed on a photographic film (hereinafter referred to as a film) such as a negative film or a reversal film is printed on a photosensitive material (photographic paper) by projecting an image of the film onto the photosensitive material. Surface-exposing the photosensitive material,
This is performed by so-called direct exposure (analog exposure).

On the other hand, in recent years, a printing apparatus using digital exposure, that is, an image recorded on a film is photoelectrically read, the read image is converted into a digital signal, and then various image processing is performed. 2. Description of the Related Art Digital photo printers have been put to practical use, in which image data (latent images) are recorded by scanning and exposing a photosensitive material with recording light modulated in accordance with the image data, and the resulting images are printed.

In a digital photo printer, exposure conditions at the time of printing can be determined by image data processing using an image as digital image data, so that image skipping and blurring caused by backlight, strobe photography, and the like can be corrected, and sharpness can be reduced. Properly perform (sharpening) processing, correction of color feria and density feria, correction of underexposure and overexposure, correction of peripheral light reduction, etc. to obtain high-quality prints that could not be obtained by conventional direct exposure Can be. In addition, synthesis of a plurality of images, image division, and synthesis of characters can be performed by image data processing, and prints that have been freely edited / processed according to the intended use can be output.
In addition, according to the digital photo printer, a print can be created from an image (image data) photographed by a digital camera or the like, and the image can be printed (photograph).
In addition to outputting the image data, the image data can be supplied to a computer or the like, or can be stored in a recording medium such as a floppy (registered trademark) disk, so that the image data is used for various purposes other than a photograph. be able to.

[0005] Such a digital photo printer basically includes a scanner (image reading apparatus) for photoelectrically reading an image recorded on a film, and an image processing apparatus for processing the read image into image data for recording. Equipment, and
The printer comprises a printer (image recording apparatus) that scans and exposes the photosensitive material in accordance with the image data, performs development processing, and prints.

In a scanner, reading light emitted from a light source is incident on a film to obtain projection light carrying an image photographed on the film, and the projection light is transmitted to an image of a CCD sensor or the like by an optical system imaging lens. An image is read by forming an image on a sensor and photoelectrically converting the image. After performing various image processing as necessary, the image is sent to an image processing apparatus as image data (image data signal) of a film. The image processing apparatus sets image processing conditions from image data read by a scanner, performs image processing according to the set conditions on the image data, and outputs the image data to a printer as output image data (exposure conditions) for image recording. send. In a printer, for example, if the apparatus uses light beam scanning exposure, the light beam is modulated according to image data sent from the image processing apparatus, and the photosensitive material is two-dimensionally scanned and exposed (printed). A print (photograph) in which a latent image is formed and then subjected to predetermined development processing and the like, and an image photographed on a film is reproduced.
And

[0007] By the way, the causes of deterioration of the image quality of an image reproduced in a print include chromatic aberration of magnification, distortion, decrease in peripheral light amount, and chromatic aberration caused by the taking lens of the camera that took the image.
Examples include image out-of-focus and chromatic aberration of magnification and distortion caused by an imaging lens of an image reading device that reads photoelectrically, a decrease in peripheral light amount, and shading caused by an optical system including an image out-of-focus and an imaging lens of the image reading device. .

[0008] A color image is formed by three primary colors of red (R), green (G) and blue (B). Since the refractive index (imaging magnification) of a lens is slightly different depending on the wavelength, R, R
The imaging magnifications of the G and B lights are different, that is, chromatic aberration of magnification occurs, and color shift occurs in the obtained image. Also,
In order to obtain an appropriate captured image, a plane perpendicular to the optical axis in the scene needs to be formed on the same plane perpendicular to the optical axis. However, in a normal lens, an image plane shifts in the optical axis direction, that is, a so-called distortion occurs, so that an image formed is distorted (distortion occurs), and the obtained image is distorted. In addition, the peripheral part becomes darker than the central part due to the performance of the taking lens and the imaging lens, and the peripheral part becomes darker. Out-of-focus and the like also cause deterioration of image quality. Furthermore, due to the non-uniform light amount of the light source of the optical system, the performance of the imaging lens, and the performance of the entire optical system, the reading light emitted from the light source itself may have uneven light intensity, and the light amount irradiated on the image may be reduced. Shading that causes unevenness and consequently causes unevenness in density also causes deterioration in image quality.

For a camera such as a single-lens reflex camera which can afford a certain amount of cost, a high-precision photographing lens is used, and a combination of a plurality of lenses is used.
It is possible to suppress the deterioration of the image quality of the image caused by the taking lens. In addition, if the image reading device can be costly to some extent, an image forming lens is used by using a high-precision image forming lens, further combining a plurality of lenses, and using a precise optical system. Image degradation due to the optical system can be suppressed. However, a lens-equipped film or an inexpensive compact camera cannot add cost to a lens, and a simple and small image reading device cannot add much cost to an imaging lens or an optical system. In this case, chromatic aberration of magnification, distortion, a decrease in peripheral light quantity, image out-of-focus and shading occur. As a result, there is a problem that an image reproduced as a print becomes an image having deteriorated image quality.

To solve such a problem, Japanese Patent Application Laid-Open No. 9-28
As disclosed in Japanese Patent No. 1613, there is provided a photographic processing device that acquires information and the like regarding a photographing lens, determines image quality degradation based on the acquired information, and corrects image quality degradation based on the determined degradation state. is suggesting. In the above-described photo processing device, the deterioration state of the image quality of the image is determined based on the acquired information on the photographing lens and the like, and the correction amount of the entire image is obtained in accordance with the determination, and the entire image is corrected. It is possible to correct chromatic aberration of magnification, distortion, reduction in peripheral light quantity, and image out-of-focus.

[0011]

In the above-mentioned photographic processing apparatus, the chromatic aberration of magnification of the image caused by the photographing lens,
When correcting distortion, a decrease in peripheral light amount, and out-of-focus state, the entire image is corrected by obtaining the correction amount for the entire image. Therefore, it is necessary to obtain the correction amount for each pixel. Depending on the size of the image, for example, 200
Even for large image data such as image data of 0 × 1000 pixels, a correction amount must be obtained for each pixel. Therefore, there has been a problem that the processing time required to calculate and calculate the correction amount for each pixel increases. In addition, it is conceivable to store and hold correction data for each pixel of an image in which a correction amount for performing correction on image data is obtained in advance for each pixel, but the storage capacity required for the correction data is large. And it takes a long time to read the correction data, so that efficient image correction cannot be performed, and a simple and small-sized image reading device cannot be realized.

Further, in the above-described photographic processing apparatus, the state of deterioration of the image quality of the image is determined based on information on the photographing lens and the like, and the image is corrected in accordance with the determination. Deterioration of image quality due to the imaging lens and the optical system cannot be suppressed.

In order to solve the above problems, the present invention provides an image processing apparatus which performs image correction by using image data of an optically captured image as input image data and obtains image data for output. When performing image correction to correct the deterioration of image quality caused by the optical system including the imaging lens of the image and the imaging lens of the image reading device, the image correction processing time is reduced, and the image correction data It is an object of the present invention to provide an image processing apparatus capable of reducing the amount and efficiently performing image correction.

[0014]

SUMMARY OF THE INVENTION To achieve the above object, the present invention is an image processing apparatus for correcting image data of an optically formed image, which corrects deterioration of image quality. A correction unit for performing image correction on the image data,
An image processing apparatus characterized in that the correction means corrects the entire image from the correction amount of a part of the image by using the symmetry of the image quality deterioration with respect to the center point or the center line of the image area. It is.

In this case, it is preferable that the correction means corrects the deterioration of the image quality caused by the photographing lens for photographing the image or the deterioration of the image quality caused by the optical system for reading the image when obtaining the image data. Further, the image correction for correcting the image quality deterioration caused by the photographing lens is at least one of correction of distortion, correction of lateral chromatic aberration, correction of peripheral light amount reduction, and correction of out-of-focus blur caused by the photographing lens. The image correction for correcting the deterioration of the image quality caused by the optical system for image reading includes correction of shading caused by the optical system, correction of distortion caused by the imaging lens of the optical system, and correction of the imaging lens. At least one of correction of lateral chromatic aberration caused by the imaging, correction of decrease in peripheral light amount caused by the imaging lens, and correction of image out-of-focus caused by the imaging lens. In it is preferred.

It is preferable that the correction means calculates a correction amount of a part of the image by using a correction function and corrects the entire image using the correction amount. In consideration of the symmetry of the correction function with respect to the center position or center line of the image, correction data in which a correction amount of a part of the image is calculated in advance may be held, and the entire image may be corrected using the correction data. At this time, it is preferable that the capacity of the storage unit for holding the correction data is smaller than the storage capacity required for holding the correction data of the entire image. Further, the shading correction is a method for photoelectrically reading a light amount unevenness correction amount determined from an aperture value or a zoom magnification of an optical lens that forms an image photographed on a film in order to photoelectrically read image data. It is preferable to perform the correction using the reading sensitivity for each pixel.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image processing apparatus according to the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 is a block diagram showing an example of a digital photo printer 10 including an image processing apparatus according to the present invention.
A digital photo printer (hereinafter, referred to as a photo printer 10) shown in FIG. 1 basically includes a scanner (image reading device) 12 that photoelectrically reads an image captured on a film F, An image processing device 14 for performing image processing and overall operation and control of the photo printer 10; and imagewise exposing a photosensitive material (photographic paper) with a light beam modulated in accordance with image data output from the image processing device 14, and developing the image. And a printer 16 for processing and outputting as a (finished) print. The image processing apparatus 14 includes an operation system 1 having a keyboard 18a and a mouse 18b for inputting (setting) various conditions, selecting and instructing processing, and inputting instructions such as color / density correction.
8 and a monitor 2 for displaying images read by the scanner 12, various operation instructions, setting / registration screens for various conditions, and the like.
0 is connected.

The scanner 12 is a device for photoelectrically reading an image photographed on a film F or the like one frame at a time.
And a variable aperture 24 and R, G and B for separating the image into three primary colors of R (red), G (green) and B (blue).
A color filter plate 26 having a plurality of color filters and rotating to apply an arbitrary color filter to an optical path; a diffusion box 28 for making reading light incident on the film F uniform in a surface direction of the film F; A lens unit 32 and a CCD sensor 3 serving as an area sensor for reading one frame image of the film;
4, an amplifier (amplifier) 36, and the light source 22, the variable aperture 24, the color filter plate 26, the diffusion box 28, and the imaging lens unit 32 form an optical system 33.

In the illustrated example of the photo printer 10, a new photo system (Advanced Photo System) or 13
Depending on the type and size of the film such as a negative (or reversal) film of 5 sizes, the form of the film such as strips and slides, and the type of processing such as trimming,
A dedicated carrier that can be freely mounted on the main body of the scanner 12 is prepared. By changing the carrier, it is possible to cope with various films and processes. An image (frame) photographed on a film and provided for print production is conveyed and held at a predetermined reading position by this carrier. Also, as is well known, a magnetic recording medium is formed on the film of the new photographic system, and a cartridge ID, a film type, and the like are recorded. Various data such as the type of the camera and the developing machine can be recorded. The carrier corresponding to the film (cartridge) of the new photographic system is provided with a means for reading the magnetic information. The magnetic information is read when the film is transported to the reading position. Sent to

In such a scanner 12, the reading light emitted from the light source 22, adjusted in light quantity by the variable aperture 24, passed through the color filter plate 26, adjusted in color, and diffused in the diffusion box 28 is transmitted by the carrier. The light is incident on and transmitted through one frame of the film F held at a predetermined reading position, thereby obtaining projection light carrying an image of the frame photographed on the film F. The projection light of the film F is transmitted to the CCD sensor 3 by the imaging lens unit 32.
An image is formed on the light receiving surface of No. 4 and photoelectrically read by the CCD sensor 34, and its output signal is amplified by the amplifier 36 and sent to the image processing device 14. CCD sensor 34
Is, for example, an area CCD sensor having 1380 × 920 pixels.

In the scanner 12, such an image reading is performed three times by sequentially inserting the respective color filters of the color filter plate 26, so that one frame of image is read by R, G and B.
And read out. Here, in the photo printer 10, a pre-scan for reading an image at a low resolution is performed in order to determine image processing conditions and the like, before reading an image for printing a print (main scan). Therefore, a total of six image readings are performed in one frame.

The scanner 12 uses an area CCD sensor and separates projection light into three primary colors by a color filter plate 26 to read an image. The scanner used in the present invention reads each of the three primary colors. 3 corresponding to
An image may be read by slit scanning for reading an image while scanning and transporting the film F by a carrier using a type of line CCD sensor.

The illustrated photo printer 10 uses a scanner 12 that photoelectrically reads an image photographed on a film such as a negative or a reversal as an image data supply source of the image processing device 14. As an image data supply source for supplying the image data, other than the scanner 12, an image reading device that reads an image of a reflection original, an imaging device such as a digital camera or a digital video camera, an LA
Communication means such as N (Local Area Network) and computer communication network; various image reading means and imaging means such as a memory card and a medium (recording medium) such as MO (magneto-optical recording medium); storage means for image data; Can be used in various ways. In the present invention, the image obtained from these means only needs to be at least optically photographed.

An output signal (image data) from the scanner 12 is output to the image processing device 14. FIG. 2 shows a block diagram of an image processing device (hereinafter, referred to as a processing device 14). The processing device 14 includes a data processing unit 38, a prescan (frame) memory 40, a main scan (frame) memory 42, a prescan image processing unit 44, a main scan image processing unit 46, and a condition setting unit 48. Is done. FIG. 2 mainly shows parts related to the image processing.
C that controls and manages the entire photo printer 10 including the printer 4
PU, a memory for storing information necessary for the operation of the photo printer 10, etc., an aperture value of the variable aperture 24 (an aperture value of the imaging lens unit 32) and a CCD sensor 3 at the time of main scanning.
For example, means for determining the storage time of No. 4 are arranged, and the operation system 18 and the monitor 20 are connected to each part via the CPU or the like (CPU bus).

The data processing unit 38 converts the R, G, and B output signals output from the scanner 12 into A / D (analog / digital) conversion, Log conversion, DC offset correction, dark correction, shading correction, and the like. Is the part that performs In the photo printer 10, for example, the diffusion box 28
If it is difficult to form the precise optical system 33 at a high cost with respect to the imaging lens unit 32 and the like, shading, that is, unevenness in the light intensity of the irradiation light is likely to occur. For example, light intensity is high near the center of the image, and low near the center. The intensity of the light is determined by the diffusion box 28.
This is caused not only by the optical system 33 and the imaging lens unit 32 but also by the optical system 33 of the scanner 12, that is, the entire optical system 33 including the light source 22, the variable aperture 24, the color filter plate 26, and the like. Therefore, in such a photo printer 10, it is necessary to appropriately perform shading correction by adjusting the brightness of the image from the correction amount of the light amount so that an image with a substantially uniform light amount can be obtained. Further, since shading changes depending on the aperture value or zoom magnification of the imaging lens unit 32, the correction amount of the shading correction also changes according to the aperture value or zoom magnification.

The amount of such shading correction is
It is determined as the amount of correction of the amount of light and depends on the aperture value and zoom magnification.
Correction amount determined according to the aperture value and zoom magnification.
From a number, for example, a second-order or third-order polynomial, for each pixel position.
Confuse. At that time, as shown in FIG.
The center line X of the image area shown in FIG._ThreeAnd center line Y_ThreeTimes
Almost line-symmetric, and the center point O_ThreeAbout point symmetry around
Use this symmetry to provide the feature
A_ThreeB_ThreeC_ThreeD_ThreeArea A of 1/4_ThreeE_ThreeO _ThreeF_ThreeTo
A correction operation is performed for each pixel to obtain a correction amount._ThreeE
_ThreeO_ThreeF_ThreeThe correction data consisting of the correction amount of
It is stored and stored in the storage unit not shown, and the correction data
To obtain the correction amount, and use this correction amount to
Area, eg area A_ThreeE_ThreeO_ThreeF_ThreeAnd center line Y_ThreeAnd line symmetry
Area E_ThreeB_ThreeG_ThreeO_ThreeImage correction.
Thus, image correction of the entire image can be performed. like this
Correction using shading symmetry to be corrected
Reduce the number of calculations and reduce the amount of correction data
Than the storage required to hold body correction data
Efficient shading correction that can be reduced
It can be performed.

Further, a correction amount corresponding to an aperture value or a zoom magnification for each pixel may be stored and held in a storage unit as correction data in advance, and the correction amount may be obtained by calling up the correction data as needed. Since the correction amount for shading correction is a correction amount related to the light amount, it is necessary to consider in advance the sensitivity unevenness of the CCD element constituting the CCD sensor 34 when the scanner 12 photoelectrically reads an image, and to set the correction amount for each pixel in advance. The data in which the reading sensitivity is stored is called up, and the image data is corrected according to the sensitivity of the CCD element.

The data processing section 38 processes the pre-scan image signal and the main scan image signal into pre-scan data and main scan data, respectively.
At 0, the main scan data is stored (stored) in the main scan memory 42, respectively. The pre-scan data and the main scan data are basically the same data except that the resolution (pixel density) and the signal level are different.

The pre-scan data stored in the pre-scan memory 40 is processed in the pre-scan image processing section 44, and the main scan data stored in the main scan memory 42 is processed in the main scan image processing section 46. The pre-scan image processing unit 44 includes an LUT / MT
It has an X operation unit 44A, an image processing unit 44B, and a data conversion unit 44C. On the other hand, the main scan image processing unit 46 includes an LUT / MTX operation unit 46A and an image processing unit 4A.
6B and a data conversion unit 46C.

The LUT / MTX operation unit 44A and the LUT / M
The TX calculation unit 46A performs color balance adjustment, contrast correction (gradation processing), and brightness adjustment on an image (image data) read by the scanner 12 in accordance with image processing conditions set by a condition setting unit 48 described later. This is a portion for performing correction, saturation correction, and the like. These processes are performed by a known method such as a process using an LUT (look-up table), a matrix (MTX) operation, and the like.
Brightness correction and contrast correction are performed in the LUT,
Saturation correction is performed by MTX calculation.

The image processing unit 44B and the image processing unit 46B
This portion corrects aberration of the lens caused by the image pickup lens of the image read by the scanner 12 and the lens caused by the imaging lens unit 32 of the scanner 12, correction of a decrease in peripheral light amount, and correction of image out-of-focus. Here, in order to determine the photographing lens, for example, when the film F is a film with a lens of the new photographic system, the magnetic information recorded on the film F is transferred to a magnetic head (not shown) provided on the carrier of the scanner 12. And the type of the film with the lens, that is, the camera, can be determined by using the cartridge ID and the film type, etc., which have been read and magnetically recorded, and the extended DX code “SS” optically recorded on the film can be determined.
U INDICATOR "can be optically read by a carrier and used. In addition, some cameras supporting the new photographic system have a function of magnetically recording the model of the camera on the film F, and the camera that has photographed the film F may be discriminated using this. At the time of reception, the model of the lens-equipped film or the type of the photographing camera is heard from the customer, and recorded in a memo, package, patrone, cartridge, or the like.
The model of the camera may be input with a, or the correspondence between the function key and the camera and the camera may be determined instead of the model of the camera, and the input may be performed using this. Further, the camera model may be optically printed on the film at the time of photographing, and read to determine the camera model. In the case of a film with a lens, the model of the film with a lens may be optically printed like a DX code or magnetically recorded at the time of manufacture or the like, and the model may be determined using these. Further, in the case of a film cartridge with an IC memory, the model of the camera or the like may be electrically recorded in the IC memory, and the model may be determined using this.

Using the information on the determined camera model and the like, a lens characteristic data unit 47 described later is used to correct image quality deterioration due to the photographing lens, that is, to correct aberrations, reduce peripheral light quantity, and correct image out-of-focus. The coefficient of the correction equation to be used is called, and the correction equation can be obtained from the coefficient. Further, correction data created by previously obtaining a correction amount may be called. Since the lens characteristics of the imaging lens unit 32 used in the scanner 12 are known in advance, the coefficients of the correction formula used for the correction operation for performing the image correction are stored in the lens characteristic data unit 47 in advance, and the image processing unit 44B Each time the image processing unit 46B performs image correction, the coefficient of this correction formula can be called. Further, correction data created by previously obtaining a correction amount may be called.

Here, correction of aberrations caused by the photographing lens and the imaging lens unit 32 includes correction of distortion and correction of chromatic aberration of magnification. A correction formula obtained together with a coefficient from the lens characteristics of the imaging lens unit 32 and information on the position of the image data (pixel), for example, the coordinate position (center pixel) from the center of the image (the center of the optical axis of the imaging lens) Is used to calculate the movement correction amount at each pixel position. Further, the image data may be corrected by calling up the correction data in which the correction amount is created in advance.

The distortion means that the image of the lattice pattern photographed on the film shown in FIG. 4A is shown in FIG. 4B by the characteristics of the photographing lens and the imaging lens unit 32 of the scanner 12. Correction refers to a state in which the image itself is distorted into a pincushion shape or the like, and the correction of distortion is performed by using a correction formula for calculating a correction amount for this distorted image or creating a correction amount for each pixel in advance. Using the correction data, FIG.
This is a correction for returning the image to the lattice pattern as shown in FIG.

Assuming that the center point of the image is the center point O ₄ as shown in FIG. 4A, the distortion is point-symmetric around the center point O ₄ as shown in FIG. Assuming that the center line of the image is the center line X ₄ and the center line Y ₄ , the image is symmetric about the center line X ₄ and the center line Y ₄ . Therefore, the correction amount for correcting the distortion is also point-symmetric about the center point O _{4 and} is also line-symmetric about the center line X ₄ and the center line Y ₄ . Therefore, only the correction amount of a quarter of the image area A ₄ B ₄ C ₄ D ₄ divided by the center line X ₄ and the center line Y ₄ , for example, the area A ₄ E ₄ O ₄ F ₄ is obtained. By using symmetry or point symmetry, the correction amount of another area can be determined. In the present embodiment, the correction amount is obtained for a quarter of the image region, but is not limited thereto, and the correction amount is obtained for a partial region of the image region, such as a half region of the image region. What is necessary is just to obtain.

As shown in FIG. 5A, the magnification chromatic aberration means that an image photographed on the film F is a virtual rectangle A _5.
In the case of the image of the straight line E ₅ F ₅ passing on the point A _{5 of} B ₅ C ₅ D ₅ , as shown in FIG. 5B, the R pixel, the G pixel and the B pixel of the straight line E ₅ F ₅ Correction of chromatic aberration of magnification refers to a state in which a color shift occurs due to a shift in position, and a correction amount is obtained using a correction formula for each pixel position with respect to this color-shifted image, and FIG. As in c), the pixel positions of the R pixel, G pixel, and B pixel are corrected. For example, the correction is for correcting the positions of the R pixel and the B pixel on the straight line E ₅ F _{5 based on} the position of the G pixel. As in the case of the correction of the distortion, the correction data in which the correction amount is created in advance for each pixel is stored and stored, and if necessary, the correction data may be called to obtain the correction amount.

[0038] Such lateral chromatic aberration is about the point symmetry of the center point O ₅ as shown in FIG. 5 (a), also the center line X ₅
Because it is around the line symmetry or center line Y _5, the correction amount of the correction amount and the B pixels of the R pixel for correction of the lateral chromatic aberration, like the correction amount for correcting the distortion, the image area quarter of the area delimited generally by centerline X ₅ and the center line Y _5, for example, only the correction amount of area a ₅ E ₅ O ₅ F ₅ determined by correction calculation, in other areas with this The correction amount of the R pixel and the correction amount of the B pixel can be determined using line symmetry or point symmetry. In the present embodiment, similarly to the above-described distortion correction, the correction operation is performed on a quarter of the image region to obtain the correction amount. However, the present invention is not limited to this. Any device may be used as long as it performs the correction operation. The correction amount in the distortion and lateral chromatic aberration, the region as indicated part of the area of the image area, for example, in FIG. 4 (a), for example, an area A ₄ E
_The correction data obtained by performing a correction operation in advance on the correction amount of a quarter of the image area such as ₄ O ₄ F ₄ is stored and held, and the correction data can be called up and corrected if necessary. Good.

The correction of the distortion and the correction of the chromatic aberration of magnification are collectively processed together with the electronic scaling process. That is, the shift amount of the position of the G pixel due to the distortion is obtained, and the R pixel and the B pixel are calculated from the corrected position of the G pixel.
An appropriate position is calculated for each pixel, a shift amount of the position of the R pixel and the position of the B pixel with respect to the G pixel is obtained, and image data is interpolated by using the calculated information of the appropriate position of each pixel to interpolate image data. Perform processing. In other words, by calculating the amount of displacement of the pixel position due to chromatic aberration of magnification and distortion,
It knows where each pixel should be originally located, and performs an electronic scaling process by performing an interpolation operation on the image data according to the appropriate position. There is no particular limitation on the method of the electronic scaling process, and various known methods can be used. Examples thereof include a method using bilinear interpolation and a method using spline interpolation. Thus, correction of chromatic aberration of magnification and distortion and electronic scaling processing can be performed by one interpolation calculation.

The correction of the distortion and the correction of the chromatic aberration of magnification are performed by correcting the photographing lens or the imaging lens unit 32, for example, a high-order polynomial, and information on the position of image data (pixels), for example, the center of the image (photographing). Correction of chromatic aberration of magnification and distortion and electronic scaling processing are performed using a coordinate position (the number of pixels from the center pixel) from the center of the optical axis of the lens. In this case, position coordinates of each pixel are used. Is xy
Coordinates or polar coordinates may be used. In addition, the information of the pixel position is not limited to the reference of the center point of the image, and various types of information can be used. For example, the corner (the upper left corner or the like) of the image,
A certain pixel (for example, the pixel of the pixel number 1) or the like may be used as a reference, or the outside of the image, for example, the perforation of the film F may be used as a reference. That is, if the position of the image (pixel) can be relatively detected, various kinds of position information can be used. When the center of an image cut out by a mask or the like is considered to be substantially the center of the optical axis of the lens at the time of shooting, various aberrations are set with the center pixel of the cut out image as the center of the optical axis of the lens. (Distortion aberration, lateral chromatic aberration, decrease in peripheral light amount, out-of-focus image) may be corrected.

The image processing unit 44B and the image processing unit 46B can also perform correction of image out-of-focus and a decrease in peripheral light amount caused by the photographing lens and the imaging lens unit 32. For example, the peripheral light amount reduction to be corrected for the peripheral light amount is, as shown in FIG. 6A, uneven in the light amount due to the taking lens and the imaging lens unit 32, and the image area A ₆ B ₆ A state in which the lightness value of C ₆ D ₆ decreases in accordance with the cosine fourth law as it moves away from the center point O ₆ of the image area. The correction amount for each pixel position is obtained by using a correction formula determined by the characteristics of the photographing lens and the imaging lens unit 32 so that the value of the image data (brightness value) increases as the pixels are located in the peripheral area. Refers to correction. Further, the correction data obtained by performing the correction calculation in advance may be stored, and the correction data may be called up to obtain the correction amount as needed.

As shown in FIG. 6 (a), the peripheral light has a point symmetrical feature around the center point O ₆ of the image, so that the center line X ₆ and the center line Y ₆ are reduced. A correction amount is obtained by performing a correction operation on a part of the image area A ₆ B ₆ C ₆ D ₆ delimited by, for example, only the correction amount of the area A ₆ E ₆ O ₆ F ₆ from a correction formula, and using this to obtain another correction amount The correction amount of the region is determined in consideration of the line symmetry and the point symmetry, and an image having a brightness distribution as shown in FIG. FIG. 6C shows a method of correcting a decrease in the peripheral light amount. The gradient of the conversion straight line 1 is determined for each pixel, and image data is corrected based on the light amount correction amount ΔI. That is, the image data before the correction of the decrease in the peripheral light amount is converted into the light amount of the subject using the sensitivity of the CCD element of the CCD sensor 34, and the correction amount ΔI is obtained from the correction formula determined by the photographing lens and the imaging lens unit 32. Is corrected. The corrected subject light amount is converted into image data to obtain corrected image data. In this case, since the sensitivity of the CCD element of the CCD sensor 34 (the sensitivity of the signal value of the image data with respect to the light amount) differs for each pixel, the gradient of the conversion straight line 1 shown in FIG. The sensitivity unevenness can be corrected by calling as needed. Also,
As in the case of the correction of the distortion and the correction of the chromatic aberration of magnification, a partial area of the image area A ₆ B ₆ C ₆ D ₆ , for example, the area A
₆ E ₆ O ₆ F 1 area of a quarter of an image area as a _sixth correction amount in advance correction operation to perform correction data created stores and holds, as necessary subjected to call correcting the correction data You may.

In the image processing units 44B and 46B, when the shading correction in the data processing unit 38 includes the correction of the decrease in the peripheral light amount caused by the imaging lens unit 32,
The correction of the decrease in the peripheral light amount is not performed in the image processing units 44B and 46B so that the correction of the decrease in the peripheral light amount does not overlap.

Image processing unit 44B and image processing unit 46B
Is a photographing lens or a scanner 12 of a camera that has taken an image.
The image processing device of the present invention performs image correction due to the imaging lens unit 32, but the image processing device of the present invention corrects an image whose image quality has deteriorated due to the photographing lens and the image quality has deteriorated due to the imaging lens unit 32. Not only for image correction,
It may correct an image whose image quality has deteriorated due to both the taking lens and the imaging lens unit 32. In this case, the correction formula for the taking lens and the correction formula for the imaging lens unit 32 can be added and corrected collectively.

As described above, in the image correction for suppressing the deterioration of the image quality caused by the lens such as the photographing lens and the image forming lens, the number of correction operations is reduced by utilizing the symmetry of the image quality deterioration in the image area. , And the amount of correction data created in advance,
The storage capacity required to hold the correction data of the entire image can be reduced, and efficient image correction can be performed.

The image processing section 44B and the image processing section 46B can perform dodging processing and sharpness processing as required. The image data corrected by the image processing unit 44B and the image processing unit 46B is sent to the data conversion unit 44C and the data conversion unit 46C. The data conversion unit 44C converts the image data processed by the image processing unit 44B using a 3D (three-dimensional) -LUT or the like, and converts the image data into image data corresponding to display on the monitor 20. On the other hand, the data conversion unit 46C is a unit that similarly converts image data processed by the image processing unit 46B using the 3D-LUT and supplies the image data corresponding to image recording by the printer 16 to the printer 16. .

The lens characteristic data section 47 stores lens characteristic information corresponding to various camera models, specifically, a correction formula used for correcting aberrations of various lenses, correcting a decrease in peripheral light amount, and correcting image out-of-focus. Is stored. Further, correction data for which a correction amount has been obtained in advance may be stored and held. In this case, the distortion of the lens, the chromatic aberration of magnification, the peripheral light amount distribution characteristic, and the characteristic of the out-of-focus image have symmetry with respect to the image center line and symmetry with respect to the image center point when viewed from the entire image area. The correction data of a part of the image area, for example, FIG.
As shown in (a), the entire image area A ₄ B ₄ C ₄ D ₄
Only the correction data of the area A ₄ E ₄ O ₄ F ₄ , which is one- _fourth , is stored and held. As a result, the storage capacity for holding the correction data is much smaller than the storage capacity required for holding the correction data for the entire image area, the correction storage capacity is reduced, and the calling time required for calling the correction data is reduced. And the processing time of the image processing can be reduced.

In this embodiment, the correction formula and the correction data are stored in the storage unit of the lens characteristic data unit 47. However, the present invention is not limited to this, and may be stored in a database connected to the photo printer 10, for example. The information may be read out by accessing this place, or may be externally input as information of a lens corresponding to the film when reading the film F.

The condition setting section 48 selects image processing to be performed, sets image processing conditions in the pre-scan image processing section 44 and the main scan image processing section 46 using pre-scan data, and integrates parameters. Specifically, from the pre-scan data, a density histogram is created, and image feature values such as average density, LATD (large area transmission density), highlight (lowest density), and shadow (highest density) are calculated. In addition, according to an operator's instruction using the operation system 18 performed as needed, a table (LUT) for gray balance adjustment, brightness correction, and contrast correction, and a matrix operation for performing saturation correction are generated. Is determined. Keyboard 18
The brightness, color, contrast, sharpness, saturation, and the like set by a are calculated in accordance with various input instructions and the like, and the amount of image processing condition adjustment (for example, the amount of LUT correction) is calculated. Integrate as parameters and reset image processing conditions.

The configuration of the processing device 14 has been described above. Hereinafter, the operation of the processing device 14 will be described.

R and G read by the scanner 12 and
Each output signal of B is A / D (analog / digital) conversion.
Log conversion, DC offset correction, darkness correction,
For example, reading correction is performed. Where shading
The correction is performed using the aperture value of the imaging lens unit 32 or the zoom.
The shading changes according to the magnification, so the aperture value
The shading correction amount according to the
I can. Such a correction amount, as shown in FIG.
Body area A_ThreeB_ThreeC_ThreeD_ThreeArea A of 1/4_ThreeE_ThreeO
_ThreeF_ThreeIs calculated for each pixel to determine the amount of correction.
Using a positive quantity, the center line X_ThreeUsing the line symmetry of
O_ThreeH_ThreeD_ThreeF_ThreeOf the center line Y_Threeof
Using the line symmetry, the region E_ThreeB_ThreeG_ThreeO_ThreeCorrection amount
And the center point O_ThreeUsing the point symmetry around
Area O_ThreeG_ThreeC_ThreeH_ThreeIs calculated, and the area of the entire image is calculated.
A _ThreeB_ThreeC_ThreeD_ThreeImage correction. In addition, the correction amount
To the amount of light that was created and stored in a storage unit (not shown).
The correction amount is obtained by calling the correction data
This may be used. When shading correction,
A CCD sensor for photoelectrically reading an image with the scanner 12.
Considering the sensitivity unevenness of the CCD element constituting the
Corrects image data according to the sensitivity of the CCD element for each element
Do.

A / D (analog / digital) conversion, Lo
After performing g conversion, DC offset correction, darkness correction, shading correction, and the like, the prescan data is sent to the prescan memory 40.

When the pre-scan data is sent to and stored in the pre-scan memory 40, the condition setting section 48 reads out the pre-scan data, creates a density histogram, calculates an image feature amount, and uses the data to generate an image. Set processing conditions (create LUT and MTX). The set image processing conditions are integrated and sent to the pre-scan image processing unit 44 and the main scan image processing unit 46.

Various instructions and information input by the keyboard 18a and the mouse 18b and magnetic information of the film F read by the carrier of the scanner 12 are sent to the image processing device 14, and the image of the camera When the information is input, the magnetic information is sent to the lens characteristic data unit 47 via the condition setting unit 48. In the lens characteristic data 47, coefficients of a correction formula are read out as lens characteristic data from the obtained magnetic information, and the image processing unit 44B
Sent to Alternatively, the correction data may be read out in advance, and the correction data may be sent to the image processing unit 44B.

Next, the pre-scan data is read from the pre-scan memory 40, and the LUT / MTX operation unit 4 is read.
4A, according to the set image processing conditions, the scanner 1
2, color balance adjustment, contrast correction (gradation processing), brightness correction,
The image data is subjected to saturation correction and the like, and sent to the image processing unit 44B.

In the image processing section 44B, the coefficient sent from the lens characteristic data section 47 is given as a correction equation, for example, a coefficient of a second-order or third-order higher-order polynomial. Is used to calculate and obtain a correction amount, and correction of distortion and chromatic aberration of magnification due to the imaging lens and the imaging lens unit 32 of the scanner 12, correction of out-of-focus image, and correction of reduction in peripheral light amount are performed. Alternatively, when correction data in which a correction amount at each pixel position is obtained in advance from the lens characteristic data unit 47, correction of distortion and chromatic aberration of magnification and correction of image out-of-focus using the correction amount obtained from the correction data are performed. And a reduction in peripheral light quantity is performed.
For example, as shown in FIG. 4A, correction of distortion and chromatic aberration of magnification at position coordinates having two axes X and Y orthogonal to each other along the edge of the image area is shown in FIG. A method of correcting the distortion and the chromatic aberration of magnification in the X-axis direction will be described.

[0057] Correction of the X-axis direction of the distortion and lateral chromatic aberration are place, for example, the position coordinates x _c and y _c of the center point of the image area relative to the position of the corner point B ₄ of the image Based on the input and the position coordinates x _i and y _{i of the} G pixel for which image correction is to be performed, the position coordinates from the center point of the pixel of the image area for which distortion is to be corrected are determined. On the other hand, using the coefficients obtained by the lens characteristic data unit 47, a correction equation D _out (x, y) for distortion represented by a higher-order polynomial is obtained, and the position coordinates from the center point obtained earlier and Correction formula D
determined by calculating the correction amount from the _out (x, y), by adding the correction amount to the position coordinates x _i, performs a correction of distortion in the X-axis direction, a pixel position in the X-axis direction after correction Get.

The G pixel serves as a reference for calculating the amount of displacement between the R pixel and the B pixel in the subsequent correction of the chromatic aberration of magnification, and the chromatic aberration of magnification is not corrected. Therefore, the pixel position of the G pixel corrected by the distortion correction is the pixel position of the G pixel after the correction by the correction of the curvature aberration and the correction of the chromatic aberration of magnification. On the other hand, R
The correction of the chromatic aberration of magnification of the pixel and the B pixel is performed by correcting the chromatic aberration of magnification R _out (x, y) and B _{out of the} chromatic aberration of magnification expressed by a higher-order polynomial using the coefficient obtained in the lens characteristic data unit 47.
_out (x, y), and using these correction formulas and the corrected position coordinates of the G pixel subjected to the distortion correction, the correction amount of the lateral chromatic aberration of the R pixel and the B pixel is obtained. By adding the corrected position coordinates of the G pixel in the X-axis direction to
The corrected position coordinates in the X direction of the R pixel and the G pixel corrected for the distortion and the chromatic aberration of magnification are obtained. that time,
As shown in FIG. 4A and FIG. 5A, the distortion and the chromatic aberration of magnification are point-symmetric around the center point O ₄ and the center point O ₅ , and further, the center line X ₄ and the center line X ₅ and the center line Y ₄ or the center line Y ₅ , the region is symmetrical with respect to the entire image region, for example, the region A ₄ E
A correction operation is performed on each pixel position in ₄ O ₄ F ₄ and the region A ₅ E ₅ O ₅ F ₅ to obtain a correction amount, and a correction amount in another region is determined by using the above symmetry, and this correction is performed. The corrected pixel position is obtained from the amount, and the distortion and the chromatic aberration of magnification are corrected. Further, when the lens characteristic data unit 47 stores and holds correction data in which the correction amount at each pixel position is obtained in advance, the correction amount is calculated using the correction data instead of performing the correction operation to obtain the correction amount. Then, the same correction processing as in the above method is performed.

As described above, in the image correction for suppressing the deterioration of the image quality caused by the lens, the number of correction calculations is reduced by utilizing the symmetry of the deterioration of the image quality in the image area. The amount can be less than the storage capacity required to hold the correction data for the entire image. In the above example, when only a correction operation for a quarter of the entire image region is performed, the calculation time is reduced to a quarter. Further, when correction data is used, the amount of correction data to be stored and held is also reduced. Quarter compared to the whole image area
And efficient image correction can be performed. The above is the correction of the distortion and the chromatic aberration of magnification in the X-axis direction, and the correction in the Y-axis direction is similarly performed separately from the correction in the X-axis direction.

After that, in order to perform the electron doubling process, the position coordinates x _c and the position coordinates y _c of the center point are input, and the position coordinates x _iR ′, x _{iG of the} R pixel, the G pixel and the B pixel in the X-axis direction. ',
And x _iB ′, and using this, an electronic half-size process is performed to obtain image data subjected to image correction and electronic scaling. Thereafter, dodging processing and sharpness processing are performed as necessary.

The image data corrected by the image processing unit 44B is sent to a data conversion unit 44C, and is converted into image data corresponding to display on the monitor 20 using a 3D (three-dimensional) -LUT or the like. Thereafter, the corrected pre-scan image is displayed on the monitor 20.

The operator looks at the display on the monitor 20 and
The image, that is, the processing result is checked (tested), and if necessary, the color / density, gradation, etc. are adjusted using the keys set on the keyboard 18a. The input for this adjustment is
The correction amount is sent to the condition setting unit 48 and the correction amount of the image processing condition according to the adjustment input is calculated. According to the correction amount, the correction processing is performed by the LUT / MTX calculation unit 44A and the image processing unit 44B as described above. Is displayed on the monitor 20 again.

When the operator determines that the image displayed on the monitor 20 is appropriate (OK), the keyboard 1
8a or the like is used to instruct the start of the main scan. As a result, the image processing conditions are determined, high-resolution main scan data is sent from the scanner 12, and the data processing unit 38 performs A / D (analog / digital) conversion, Log conversion, After the DC offset correction, darkness correction, shading correction, and the like are performed, the main scan data is sent to the main scan memory 42.

Thereafter, the main scan image data read from the main scan memory 42 is sent to the main scan image processing unit 46, and the LUT /
The MTX operation unit 48 performs color balance adjustment, contrast correction (gradation processing), brightness correction, saturation correction, and the like according to the determined image processing conditions, and sends the result to the image processing unit 46B. The image processing unit 46B uses the same method as the correction performed by the image processing unit 44B on the pre-scan data, and sets the photographing lens and the scanner 12 under the determined image processing conditions.
Correction of distortion caused by the imaging lens unit 32 of
Correction of chromatic aberration of magnification, correction of decrease in peripheral light amount, or correction of out-of-focus image is performed. The corrected main scan data is sent to the data conversion unit 46C, and is subjected to 3D (three-dimensional)-
The data is converted into image data to be printed and output to the printer 16 using an LUT or the like, and sent to the printer 16.

The printer 16 exposes a photosensitive material (printing paper) in accordance with the main scan data to record a latent image, performs a development process in accordance with the photosensitive material, and outputs the print as a (finished) print. For example, after the photosensitive material is cut into a predetermined length corresponding to the print, recording of the back print, red (R) exposure, green (G) exposure, and blue (B) according to the spectral sensitivity characteristics of the photosensitive material (photographic paper). ) The three types of light beams of the exposure G are modulated according to image data (recorded image),
Deflected in the main scanning direction, recording a latent image by transporting the photosensitive material in the sub-scanning direction orthogonal to the main scanning direction, etc.,
The photosensitive material on which the latent image has been recorded is subjected to predetermined wet development processing such as color development, bleach-fixing, and washing with water, dried, printed, sorted, and accumulated. Thus, the characteristics of the optical system 33 of the scanner 12 and the optical system
According to the lens characteristics of the imaging lens unit 32 and the characteristics of the taking lens of the camera that took the image, an image subjected to image correction can be obtained as a print.

Although the image processing apparatus of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various improvements and changes may be made without departing from the gist of the present invention. Of course. In the present invention, in the image processing unit 44B of the pre-scan image processing unit 44 and the image processing unit 46B of the main scan image processing unit 46, correction of distortion, correction of chromatic aberration of magnification, correction of decrease in peripheral light amount, and correction of image out-of-focus. Although the correction is performed, the main scan image processing unit 46 does not perform the correction of the distortion, the correction of the chromatic aberration of magnification, the correction of the decrease in the peripheral light amount, and the correction of the out-of-focus state in the image processing unit 44B of the pre-scan image processing unit 44. The above-described correction processing may be performed only in the image processing unit 46B. In this embodiment, the area CCD
Although the scanner is a scanner that photoelectrically reads an image using a sensor, an image may be read by slit scanning that reads an image while scanning and transporting the film F by a carrier. Since the image area has symmetry around the center line of the image area in the scanning and conveying direction, image correction can be efficiently performed using this symmetry.

[0067]

As described above in detail, according to the present invention, it is possible to suppress the deterioration of the image quality caused by the optical system such as the image reading apparatus and the image quality caused by the photographing lens and the imaging lens. When performing the correction, the entire image is corrected from the correction amount of a part of the image in consideration of the symmetry of the degree of deterioration of the image with respect to the center point or the center line of the image area, so that the image correction processing time is reduced, and Reduce the amount of image correction data,
Image correction can be performed efficiently.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a digital photo printer using an image processing apparatus according to the present invention.

FIG. 2 is a block diagram of an example of an image processing apparatus of the digital photo printer shown in FIG.

FIG. 3 is an explanatory diagram illustrating an example of image correction performed by the image processing apparatus according to the present invention.

FIGS. 4A, 4B, and 4C are explanatory diagrams showing another example of image correction performed by the image processing apparatus of the present invention.

FIGS. 5A, 5B, and 5C are explanatory diagrams illustrating another example of image correction performed by the image processing apparatus of the present invention.

FIGS. 6A, 6B, and 6C are explanatory diagrams showing another example of image correction performed by the image processing apparatus of the present invention.

FIG. 7 is an explanatory diagram showing a flow of an example of image correction performed by the image processing apparatus of the present invention.

DESCRIPTION OF SYMBOLS 10 Photo printer 12 Scanner 14 Image processing device 16 Printer 18 Operation system 18a Keyboard 18b Mouse 20 Monitor 22 Light source 24 Variable diaphragm 26 Color filter plate 28 Diffusion box 32 Imaging lens unit 33 Optical system 34 CCD sensor 36 Amplifier 38 data processing unit 40 pre-scan memory 42 actual scan memory 44 pre-scan image processing unit 46 actual scan image processing unit 47 lens characteristic data unit 48 condition setting unit

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/228 G06F 15/66 360 5C077 5/253 H04N 1/04 103E F-term (Reference) 2H106 AA72 AB04 BA22 BA26 5B047 AA01 AB04 DA04 DB01 DC07 DC09 5B057 AA11 BA17 BA24 CC02 CD12 CH01 CH07 CH11 DA16 5C022 AA00 AB68 BA18 BA19 5C072 AA01 BA05 BA08 BA17 BA19 DA02 DA23 FB12 NA02 QA17 RA12 UA02 UA06 UA11 VA03 PP03 5 PP37 PQ12 PQ22 PQ23 RR01 SS01 SS02 SS03 TT02 TT09

Claims (7)

[Claims] 1. An image processing apparatus for correcting image data of an optically formed image, comprising: a correcting unit for performing image correction for correcting image quality deterioration on the image data; An image processing apparatus that corrects the entire image from the correction amount of a part of the image using the symmetry of the image quality deterioration with respect to the center point or the center line of the image area. 2. The image processing apparatus according to claim 1, wherein the correction unit corrects a deterioration in image quality due to a photographic lens that has captured the image or a deterioration in image quality due to an image reading optical system when obtaining the image data. Image processing device. 3. The image correction for correcting deterioration of image quality caused by the photographing lens is at least one of correction of distortion, correction of chromatic aberration of magnification, correction of decrease in peripheral light amount, and correction of image out-of-focus caused by the photographing lens. The image correction for correcting the deterioration of the image quality caused by the optical system for image reading includes the correction of shading caused by the optical system,
Correction of distortion caused by the imaging lens of the optical system, correction of chromatic aberration of magnification caused by the imaging lens, correction of decrease in peripheral light amount caused by the imaging lens, and image out-of-focus caused by the imaging lens At least one of the corrections
The image processing apparatus according to claim 2, wherein: 4. The image according to claim 1, wherein said correction means obtains a correction amount of a part of said image by calculating from a correction function, and corrects the entire image using said correction amount. Processing equipment. 5. The correction means holds correction data in which a correction amount of a part of an image is calculated in advance in consideration of symmetry of the correction function with respect to a center position or a center line of the image, and uses the correction data. To correct the entire image by performing
3. The image processing device according to any one of 3. 6. The image processing apparatus according to claim 5, wherein a capacity of a storage unit for holding the correction data is smaller than a storage capacity required for holding correction data of the entire image. 7. The shading correction photoelectrically corrects a light amount unevenness correction amount determined by an aperture value or a zoom magnification of an optical lens for forming an image photographed on a film in order to photoelectrically read image data. The image processing apparatus according to claim 3, wherein the correction is performed using the reading sensitivity for each pixel when reading.