JPH06236004A - Deteriorated image recoverying system - Google Patents

Abstract

PURPOSE:To remove the factor of the deterioration of a photograph peculiar to a camera main body or a lens and to obtain the clear photograph at low cost without providing a recording device in a camera. CONSTITUTION:At the time of producing a film with a lens, information concerning the unevenness of light quantity caused by the dimming of peripheral light quantity and flare by cosine fourth-power law peculiar to the film with the lens is measured by an image processor 9, and recorded in an EEPROM 12 provided in the film with the lens. At the time of printing, an image whose deterioration is recovered based on the information recorded in the EEPROM 12 is printed and outputted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a deteriorated image restoration system for restoring a deteriorated image based on information of a deterioration factor of a photograph peculiar to a camera body or a lens.

[0002]

2. Description of the Related Art Conventionally, when a photograph is printed on a photographic printing paper, a desired photograph is printed based on information recorded on a magnetic track of a film.

For example, in Japanese Patent Laid-Open No. 2-54229, information such as trimming information for obtaining a designated print size is recorded on a recording medium such as a film, and the information is read and designated in a laboratory print processing step. Techniques for obtaining photographs of different sizes are disclosed. Further, Japanese Patent Application No. 4-129105 discloses a technique of recording blurring trajectory data during a shooting operation of a camera on a recording medium and restoring an image without blurring based on the blurring trajectory data at the time of print processing in a laboratory. ing.

[0004]

However, in the above-mentioned technique, the recording medium and the recording device are relatively large, and the cost is high.

The present invention has been made in view of the above problems, and an object of the present invention is to remove a deterioration factor of a photograph peculiar to a camera body or a lens without providing a recording device in the camera, and to make it inexpensive and clean. To get a picture.

[0006]

In order to achieve the above object, a deteriorated image restoration system according to the present invention records in advance image deterioration information such as aberration and uneven light quantity on a film with a lens. Recording means and an image restoration means for restoring the deterioration of the image photographed by the lens-attached film based on the information recorded in the recording means.

[0007]

In other words, in the deteriorated image restoration system of the present invention, the recording means records the image deterioration information such as the aberration and the unevenness of the light amount on the lens-equipped film,
The image restoration means restores the deterioration of the image photographed by the lens-fitted film based on the information recorded in the recording means.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing the configuration of a deteriorated image restoration system according to an embodiment of the present invention. This system measures the information on the unevenness of the light quantity due to the peripheral light intensity extinction due to the cosine fourth law peculiar to the lens-equipped film and the flare when manufacturing the lens-equipped film, and records it in advance on the recording medium in the lens-equipped film. Is.

As shown in the figure, a diffusing plate 2, a photographing lens 3 and a CCD line sensor 4 are provided on the optical path of the light from the light source 1.
Are arranged in order, and the CCD line sensor 4 is connected to the image processing device 9 through an amplifier circuit 6, an AD converter 7, and an I / O port 8. Further, the I / O port 8 includes a scanning device 11, a driving circuit 5, an EEPROM 12
The scanning device 11 and the drive circuit 5 are also connected to the CCD line sensor 4. The image processing device 9 is connected to the image memory 10.
The length of the CCD line sensor 4 needs to be at least longer than the lateral length of the film.

In such a structure, the light from the light source 1 is uniformly diffused by the diffusion plate 2, and the light from the diffusion plate 2 is disposed on the film surface via the taking lens 3 of the film with lens. An image is formed on the light receiving surface of the CCD line sensor 4 for measuring unevenness. Further, the CCD line sensor 4 is driven by a drive circuit 5, and the charges accumulated in each bit are sequentially converted into digital data by an AD converter 7 via an amplifier circuit 6. Then, the information on the brightness of the film surface converted into the digital data is stored in the image memory 10 via the I / O port 8 and the image processing device 9.
It should be noted that the sensor scanning device 11 vertically scans the CCD every time data relating to the brightness of one line is stored in the image memory 10.
The line sensor 4 is shifted.

By repeating the above series of operations,
The image memory 10 stores brightness data corresponding to the entire film surface. Then, as shown in FIG. 3, the image processing apparatus 9 discretely extracts the brightness data from many pixel data in the area 11 corresponding to the film surface from the image memory 10, and the data is extracted. Is written in the EEPROM 12 built in the film with lens. Next, FIG.
FIG. 3 is a diagram showing a configuration of a film with a lens in the deteriorated image restoration system of the example.

In the figure, the CCD line sensor 4 used for measurement is arranged on the film surface 13. Further, as described above, the light amount unevenness may be measured for all the lens-attached films, but since the light amount unevenness is determined at the time of design, a representative one lens-attached film light amount unevenness is measured and written to the EEPROM 12. It's enough. Furthermore, as this data, data normalized with respect to the brightness of the center of the film surface may be recorded.

In general, a photographic lens having one or two simple lens structures, such as a photographic lens of a film with a lens, has a large aberration. Therefore, it is necessary to restore an image at the time of printing based on the data written in the EEPROM 12. Is very effective. Here, a state in which the image plane is distorted is shown in FIG. 4 and will be described.

In the figure, the object-side rectangular grating 14 passes through the lens 15 and the diaphragm 16 and forms a cigar-shaped (or barrel-shaped) distorted image. In order to obtain this distortion by calculation, as shown in FIG. 5, the principal ray emitted from the off-axis object point is traced, and the point where the principal ray cuts the paraxial image plane in the image field is defined as P. The distance from the image point P0 is the size y0 of the ideal image.
Divide by and display as a percentage. The calculation is the same regardless of whether the object is at a finite distance or at infinity, and only the formula for obtaining y0 is different. Therefore, the distortion D (y0) is expressed by the following equation.

[0016]

[Equation 1] The image height y0 in the vertical direction and the distortion D (y0) in the horizontal direction are shown in the graph as shown in FIG.

When the distortion aberration is obtained by this method and the distortion aberration at an arbitrary point is used as the image deterioration information, the data capacity becomes very large. Therefore, focusing on the fact that the curve of the distortion D becomes a higher-order function of the image height y0, consider reducing the data capacity. It should be noted that the curve of the distortion D becomes a third-order distortion aberration in the camera lens amount where the angle of view is not so wide and is proportional to the square of the image height y0. Therefore, assuming that the distortion at the image height C0 is D0, the following equation is obtained.

[0018]

[Equation 2]

From the above equation (2), the distortion D at C0
If 0 is obtained, the distortion D (y0) at an arbitrary image height y0 is obtained, so that the memory saving effect is great. Incidentally, in the actual lens design, especially in the case of a wide-angle lens or an ultra-wide-angle lens, D0 is a higher-order function of y0 or higher. In this case, instead of the above equation (2), the following equation is used as the equation for obtaining the distortion aberration, and the distortion aberration information is D0, C0, K.
i should be recorded.

[0020]

[Equation 3]

Next, FIG. 7 shows, in the deteriorated image restoration system of the present invention, a negative film developed from a film photographed by a photographer and image deterioration information such as light quantity unevenness and distortion recorded on the lens-attached film. It is a figure which shows the structure of the apparatus which restores a beautiful image based on FIG.

In the figure, a uniform white light emitted from a light source 18, which is part of the scanner, illuminates a negative film 19. The negative film 19 is sequentially fed from the supply reel 20 and wound on the take-up reel 21. The scanner body 22 is composed of an optical system for forming an image of the negative film 19 illuminated by the white light source 18, a sensor, a sensor output signal processing circuit, etc., and an image is formed on the negative film from the scanner output. The RGB digital output signal of the existing image is output. Further, the image signal is sent to the I / O port 23, the image processing device 2
4 is stored in the image memory 25 via the image processing device 4, and various image quality improving processes described later are executed in the image processing device 24.

On the other hand, the EEP in the film with lens 26
Image deterioration information such as light amount unevenness and distortion recorded in the ROM 12 is stored in the data reading device 28 of the adapter 27,
It is input to the image processing apparatus through the O port 23 and the calculation for improving the image quality is executed. The image information with the improved image quality is sent to the printer 29 and printed. Hereinafter, the image processing device 24 will be described with reference to the flowchart of FIG.
The image quality improvement processing in 1 will be described in detail.

First, shading correction is performed. That is,
Here, the distortion due to the variation of the sensitivity of the CCD line sensor 4 and the unevenness of the light amount of the light source 18 is corrected (step S).
1). Then, the print density is calculated based on the average brightness of the image (step S2), and color correction is performed based on the known LATD method (large area transmission density method) (step S3).

Next, the light amount unevenness is corrected based on the light amount unevenness information read from the above-mentioned film with lens (step S4). This light amount unevenness information is recorded as discrete information on the brightness of the film surface when a diffuser plate of uniform brightness is photographed. Now, the light amount unevenness information is normalized by setting the value at the center of the film surface to "1", and the light amount unevenness information at an arbitrary position aij is set as aij.
When the image data output is Dij, the corrected image data output D'ij is expressed by the following equation (4). D'ij = Dij / aij (4)

However, since the given light amount unevenness information is discrete information, any light amount unevenness information between them will be obtained by linearly interpolating. Through the above process, the unevenness of the light amount based on the cosine fourth law of the film with lens is corrected for all the image data Dij.

Next, the distortion aberration is corrected (step S
5). That is, the information on the distortion aberration is only the image height C0 and the distortion aberration D0 at that position as described above. However, 3
In the case of the next distortion, when a higher-order aberration is added, the coefficient ki is added as shown in the above equation (3). Here, the third-order distortion will be described. This distortion is
Since the spatial coordinate is an aberration that expands or contracts into a cigar shape or a barrel shape, the correction thereof may be performed in the opposite direction, that is, the operation of contracting or expanding the space.

For example, in FIG. 9 (a), 4 which constitutes an image.
Assuming that the image height at the center of the pixel (i, j) is γ and the ideal image height without distortion is γ0, the distortion D (γ0) can be calculated from the above equation (2) by the following equation (5) ). D (γ0) = (γ0 / C0) ² D0 (5) Then, from the equations (1) and (5), the following equation holds.

[0029]

[Equation 4]

Since γ, C0 and D0 are already known,
Γ0 can be obtained from the above equation (6). Since the above equation (6) is a cubic equation with respect to γ0, it takes time to find a solution. Therefore, since γ0 and γ are almost equal, the ideal image height γ0 may be obtained by approximating D (γ0) to D (γ). The absolute amount of distortion Δγ is expressed by the following equation (7). Δγ = γ−γ0 (7)

Further, as shown in FIG. 10, pixels (i,
j is the angle between the line segment connecting the screen center (distortion = 0) C and the pixel row direction (i direction), the distortion Δi in the i direction shown in FIG. Indicated by. Δi = Δγ cos θ (8) Then, the distortion Δj in the pixel column direction (j direction) is expressed by the following equation (9). Δj = Δr sin θ (9)

As a result, the ideal position of the corrected (i, j) pixel becomes the position shown by the dotted line in FIG. 9B. Here, the image signals corrected to the positions shown by the dotted lines in FIG. 9B are (i, j), (i + 1, j), and (i, j +), respectively.
1) and (i + 1, j + 1) pixel signals contribute in proportion to the area. That is, as a pixel signal of (i, j), (I−Δi) × (J−Δj) × Di, j (i + 1, j), as a pixel signal of Δi × (J−Δj) × Dij (i, j + 1) (I−Δj) × Δj × Dij (i + 1, j + 1) as a pixel signal of Δi × Δj × ΔDij (10)

However, Dij is the brightness of the pixel (i, j) before correction. The above calculation is performed for all pixels, and the corrected output of each pixel is obtained as the total sum of the brightness contributed by each pixel in the equation (10).

When the correction of the distortion aberration is completed in this way, after the reflectance-voltage linear signal (BGR) is converted into the density-voltage linear signal (YMC) by the γ correction unit (step S).
6) A black component is generated by performing a gray component (undercolor removal: UCR) in the three-color signal (step S7). further,
Color correction masking is performed using a predetermined masking equation (step S8), gradation correction such as contrast correction is performed (step S9), and then sharpness correction such as edge enhancement smoothing is performed (step S10). Then, the image quality signal subjected to the digital signal processing is subjected to binarization processing and the like, and then sent to the printer section and printed (step S11). According to the present invention, it is possible to print a photograph whose image is restored by the above series of operations.

Although the embodiments of the present invention have been described above, it is needless to say that the present invention is not limited to these and various improvements and changes can be made. For example, although an example of writing data in the EEPROM 12 is shown in FIG. 1, since image deterioration information such as uneven light amount and distortion is determined by design, it is measured once as shown in FIG. It is also possible to reduce the cost by sticking this information to a predetermined portion of the lens-equipped film as a seal.

As described above in detail, in the deteriorated image restoration system of the present invention, the image deterioration information such as aberration and flare is recorded, and the deteriorated image can be restored by using the recorded image deterioration information at the time of printing. Even with a relatively simple camera, you can get beautiful pictures. Further, since the image deterioration information is recorded on the film with a lens, it is not necessary to provide a large-scale recording device for each camera, and a beautiful photograph can be obtained at low cost.

[0037]

According to the present invention, a deterioration image restoration system capable of obtaining a beautiful photograph at low cost by eliminating the deterioration factor of the photograph peculiar to the camera body and the lens without providing a recording device in the camera. Can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a deteriorated image restoration system according to an embodiment of the present invention.

FIG. 2 is a diagram showing an appearance of a film with a lens in the deteriorated image restoration system of the present invention.

FIG. 3 is an area 1 corresponding to a film surface of the image memory 10.
It is a figure which shows 1.

FIG. 4 is a diagram showing how the image plane is distorted.

FIG. 5 is a ray trace of a principal ray emitted from an off-axis object point, where P is a point where the principal ray cuts the paraxial image plane in the image field, and the distance between this and the ideal image point P0 is the size of the ideal image. It is a figure which shows a mode that it displayed with the percent divided by y0.

FIG. 6 is a diagram showing a state in which an image height y0 is taken in the vertical direction and a distortion D (y0) is taken in the lateral direction and shown in a graph.

FIG. 7 is a schematic view of a deteriorated image restoration system of the present invention, which is based on a negative film developed from a film photographed by a photographer and image deterioration information such as uneven light amount and distortion recorded on the lens-attached film. It is a figure which shows the structure of the apparatus which restores an image.

FIG. 8 is a flowchart for explaining in detail image quality improvement processing in the image processing device 24.

FIG. 9A shows four pixels forming an image,
(B) is a diagram showing distortion Δi in the i direction.

FIG. 10 is a diagram showing an angle θ formed by a line segment connecting a pixel (i, j) and a screen center C and a pixel row direction (i direction).

FIG. 11 is a diagram showing a state in which information represented by a bar code is used as a seal and attached to a predetermined portion of a lens-equipped film.

[Explanation of symbols]

1 ... Light source, 2 ... Diffusion plate, 3 ... Lens, 4 ... CCD, 5 ...
Drive circuit, 6 ... Amplifier circuit, 7 ... AD converter, 8 ... I
/ O port, 9 ... Image processing device, 10 ... Memory, 11 ...
Scanning device, 12 ... EEPROM, 13 ... Film surface, 1
4 ... Object, 15 ... Lens, 16 ... Aperture, 17 ... Image, 18
... light source, 19 ... film, 20 ... supply reel, 21 ... take-up reel, 22 ... scanner, 23 ... I / O port,
24 ... Image processing device, 25 ... RAM, 26 ... Lens-equipped film, 27 ... Adapter, 28 ... Data reading device, 2
9 ... Printer, 30 ... Bar code.

Claims (1)

[Claims] 1. A lens-equipped film, based on information recorded in advance, on a lens-equipped film, image-deterioration information such as aberration and light amount unevenness peculiar to the lens-equipped film. An image restoration system that restores degradation of an image captured by the image restoration system.