Image data correction method and image data correction device

Abstract

To provide an image data correction method and an image data correction apparatus which can obtain more correct data of a photographed image in an imaging apparatus whose exposure amount is discretely set.SOLUTION: An image data correction method comprises steps of: acquiring a first correction coefficient γ expressing a fluctuation degree of a state of an imaging apparatus by using a reference exposure amount that is arbitrarily set and a first exposure amount being an actual exposure amount when being set to match the reference exposure amount in the imaging apparatus; correcting an imaging exposure amount that is arbitrarily set to an imaging object by using the first correction coefficient γ to decide a target exposure amount; acquiring a photographed image of the imaging object imaged with a second exposure amount different from the target exposure amount; acquiring a second correction coefficient δ expressing a difference between the second exposure amount and the target exposure amount on the basis of the target exposure amount and the second exposure amount; and correcting the acquired photographed image by using the second correction coefficient δ.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an image data correction method and an image data correction device. [Background technology]

[0002] In pathological diagnosis, accurate observation and photography using a microscope is required to clarify the tissue microenvironment, such as the fine structure of tissue sections and the location of target protein expression.

[0003] Conventionally, when photographing tissue slices using a microscope or the like, the condition of the photographing device can change due to factors such as deterioration of the light source over time. Therefore, even if the photographing conditions are set to be consistent, the actual exposure amount can fluctuate, resulting in a problem of fluctuations in the output value of the photographed image. To address this problem, one method is to measure the light intensity of the light source using a measuring device to determine the deterioration of the light source over time and adjust the light intensity of the light source. However, this method cannot reflect fluctuations in the condition of the microscope's intermediate lens, objective lens, image sensor, etc., as well as individual differences, and therefore, the photographed image data that should be obtained cannot be obtained.

[0004] Therefore, there is a demand for a method of correcting a captured image that takes into account fluctuations in the state of the image capturing device, and an image correction method such as that disclosed in Patent Document 1 is known.

[0005] Patent Document 1 discloses a method for determining quantitative measurement values ​​of the target sample data by obtaining a light source correction factor related to the light source based on the measured value of the light intensity of the light source, applying the light source correction factor to target sample data, obtaining a microscope-specific factor that corrects for variations in the optical system such as the objective lens, and applying the microscope-specific factor to the target sample data. According to Patent Document 1, the above method makes it possible to standardize the quantitative analysis results of the target sample data. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2008 / 156669 Summary of the Invention [Problem to be solved by the invention]

[0007] However, with a photographing device in which the exposure amount is set discretely, there is a problem in that it is difficult to set the target exposure amount. Therefore, even if the method described in Patent Document 1 can correct fluctuations in the state of the photographing device, it is not possible to obtain more accurate photographed image data with a photographing device in which the exposure amount is set discretely.

[0008] The present invention has been made in consideration of the above circumstances, and aims to provide an image data correction method and an image data correction device that can obtain more accurate captured image data in a photographing device in which the exposure amount is set discretely. [Means for solving the problem]

[0009] In order to solve the above problem, an image data correction method according to one embodiment of the present invention corrects an image captured by a photographing device with a discretely set exposure amount, the method comprising the steps of: acquiring a first correction coefficient γ representing a degree of fluctuation in the state of the photographing device using an arbitrarily set reference exposure amount and a first exposure amount which is an actual exposure amount when the photographing device is set to match the reference exposure amount; correcting the arbitrarily set photographing exposure amount for a photographing subject using the first correction coefficient γ to determine a target exposure amount for the photographing subject; acquiring a photographed image of the photographing subject that was photographed at a second exposure amount different from the target exposure amount; acquiring a second correction coefficient δ representing the difference between the second exposure amount and the target exposure amount based on the target exposure amount and the second exposure amount; and correcting the acquired photographed image using the second correction coefficient δ.

[0010] In order to solve the above problem, an image correction device according to one embodiment of the present invention is an image data correction device that corrects an image captured by a photographing device in which an exposure amount is discretely set, and includes: a first correction coefficient acquisition unit that acquires a first correction coefficient γ that represents a degree of fluctuation in the state of the photographing device using an arbitrarily set reference exposure amount and a first exposure amount that is an actual exposure amount when the photographing device is set to match the reference exposure amount; a target exposure amount determination unit that uses the first correction coefficient γ to correct the photographing exposure amount that is arbitrarily set for the photographing subject and determines a target exposure amount for the photographing subject; an image acquisition unit that acquires a photographed image of the photographing subject that was photographed at a second exposure amount that is different from the target exposure amount; a second correction coefficient acquisition unit that acquires a second correction coefficient that represents the difference between the second exposure amount and the target exposure amount based on the target exposure amount and the second exposure amount; and a correction unit that corrects the acquired photographed image using the second correction coefficient δ. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an image data correction method and an image data correction device that can obtain more accurate captured image data in a photographing device in which the exposure amount is set discretely. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a flowchart of an image data correction method according to the first embodiment. [Figure 2] FIG. 2 is a flowchart showing an example of a method for determining a reference exposure amount. [Figure 3] 3A to 3E are images showing how the number of fluorescent spots increases with increasing biotin concentration in a reference object. [Figure 4] FIG. 4 is a flowchart showing an example of a method for determining the exposure amount for photography. [Figure 5] Figure 5 shows an image of a breast cancer tissue section labeled with a fluorescent substance. [Figure 6]Figure 6 shows an image of a cell emitting autofluorescence. [Figure 7] FIG. 7 is a block diagram schematically showing the functional configuration of the image data correction device according to the first embodiment. [Figure 8] FIG. 8 is a block diagram schematically showing the functional configuration of a control unit included in the image data correction device according to the first embodiment. [Figure 9] FIG. 9 is a block diagram schematically showing the functional configuration of the image acquisition unit included in the image data correction device according to the first embodiment. [Figure 10] FIG. 10 is a flowchart of an image data correcting method according to the second embodiment. [Figure 11] FIG. 11 is a block diagram schematically showing the functional configuration of an image data correction device according to the second embodiment. [Figure 12] FIG. 12 is a block diagram schematically showing the functional configuration of a control unit included in an image data correction device according to the second embodiment. [Figure 13] FIG. 13 is a flowchart of an image data correcting method according to the third embodiment. [Figure 14] FIG. 14 is a block diagram schematically showing the functional configuration of an image data correction device according to the third embodiment. [Figure 15] FIG. 15 is a block diagram schematically showing the functional configuration of a control unit included in an image data correction device according to the third embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0013] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the following embodiments.

[0014] 1. First Embodiment 1-1. Image data correction method FIG. 1 is a flowchart of an image data correction method according to the first embodiment.

[0015] As shown in FIG. 1, the image data correction method according to the first embodiment of the present invention includes the steps of (1) acquiring a first correction coefficient γ (step S110), (2) determining a target exposure for the object to be photographed (step S120), (3) acquiring a photographed image of the object to be photographed (step S130), (4) acquiring a second correction coefficient δ (step S140), and (5) correcting the acquired photographed image (step S150).

[0016] In this embodiment, the type of imaging device is not particularly limited as long as the exposure amount is set discretely. Examples of the imaging device include a microscope, a fluorescence microscope, and a whole slide scanner.

[0017] 1-1-1. Step of obtaining the first correction coefficient γ (step S110) In this process, a first correction coefficient γ that represents the degree of fluctuation in the state of the photographing device is obtained using an arbitrarily set reference exposure amount and a first exposure amount, which is the actual exposure amount when set to match the reference exposure amount in the photographing device.

[0018] The reference exposure amount is an exposure amount that serves as a reference when considering the degree of fluctuation in the state of the photographing device. The reference exposure amount can be set arbitrarily, and may be an exposure amount empirically determined for the photographing device.

[0019] The first correction coefficient γ may be obtained using a reference object. The reference object is used to calibrate the image capture device. The type of the reference object is not particularly limited, and examples thereof include a fluorescent plate, fluorescent particles, and a color calibration chart.

[0020] A fluorescent plate is a plate that emits fluorescence of a predetermined wavelength when irradiated with excitation light of a predetermined wavelength. The type of fluorescent plate is not particularly limited, and any known fluorescent plate can be used. It is preferable that the fluorescent plate has a spectrum similar to that of commonly used fluorescent dyes, specifically, that it emits fluorescence of a wavelength of 400 to 1100 nm when excited by light of a wavelength of 200 to 700 nm. When the object to be photographed contains a fluorescent substance, it is preferable that the fluorescent plate has the same or similar luminescence characteristics as the fluorescent substance contained in the object to be photographed. This allows the object to be photographed more accurately in the process of acquiring a photographed image.

[0021] Fluorescent particles are particles that emit fluorescence of a predetermined wavelength when irradiated with excitation light of a predetermined wavelength. The type of fluorescent particles is not particularly limited, and known particles can be used. Examples of fluorescent particles include quantum dots (semiconductor particles), fluorescent organic dyes, or fluorescent-substance-encapsulated nanoparticles containing multiple quantum dots. It is preferable that the fluorescent particles have a spectrum similar to that of commonly used fluorescent dyes, specifically, that emit fluorescence of a wavelength of 400 to 1100 nm when excited by light of a wavelength of 200 to 700 nm. When the object to be photographed contains a fluorescent substance, it is preferable that the fluorescent particles have the same or similar luminescence characteristics as the fluorescent substance contained in the object to be photographed. This allows for more accurate photographing of the object to be photographed in the process of acquiring a photographed image.

[0022] The quantum dots may be, for example, quantum dots containing II-VI compounds, quantum dots containing III-V compounds, or quantum dots containing IV elements as components. Examples of semiconductors that constitute quantum dots include CdSe, CdS, CdTe, ZnSe, ZnS, ZnTe, InP, InN, InAs, InGaP, GaP, GaAs, Si, and Ge. These quantum dots may also be used alone or in combination.

[0023] Quantum dots having the above quantum dots as a core and a shell formed thereon can also be used. In the following, quantum dots having a shell will be referred to as CdSe / ZnS when the core is CdSe and the shell is ZnS. Examples of quantum dots with a core-shell structure include CdSe / ZnS, CdS / ZnS, InP / ZnS, InGaP / ZnS, Si / SiO2, Si / ZnS, Ge / GeO2, and Ge / ZnS.

[0024] The quantum dots may be surface-treated with an organic polymer, etc. Examples of such quantum dots include CdSe / ZnS (manufactured by Invitrogen) having a surface carboxy group, and CdSe / ZnS (manufactured by Invitrogen) having a surface amino group.

[0025] Fluorescent substance-encapsulated nanoparticles are nanoparticles in which multiple fluorescent substances are dispersed. The fluorescent substances may or may not be chemically bonded to the nanoparticles themselves. The material that constitutes the nanoparticles is not particularly limited, and examples include silica, polystyrene, polylactic acid, and melamine.

[0026] Fluorescent substance-encapsulated nanoparticles can be prepared by known methods. For example, silica nanoparticles encapsulating fluorescent organic dyes can be synthesized by following the synthesis of FITC-encapsulated silica particles described in Langmuir, Vol. 8, p. 2921 (1992). Various fluorescent organic dye-encapsulated silica nanoparticles can be synthesized by substituting the desired fluorescent organic dye for FITC. Quantum dot-encapsulated silica nanoparticles can be synthesized by following the synthesis of CdTe-encapsulated silica nanoparticles described in The New Journal of Chemistry, Vol. 33, p. 561 (2009). Fluorescent organic dye-encapsulated polystyrene nanoparticles can be prepared by the copolymerization method using an organic dye with a polymerizable functional group described in U.S. Patent 4,326,008 or the impregnation method of fluorescent organic dyes into polystyrene nanoparticles described in U.S. Patent 5,326,692. Quantum dot-encapsulated polymer nanoparticles can be prepared by the impregnation method of quantum dots into polystyrene nanoparticles described in Nature Biotechnology, Vol. 19, p. 631 (2001).

[0027] The average particle size of the fluorescent substance-encapsulated nanoparticles is not particularly limited, but is, for example, 30 to 800 nm. The coefficient of variation (= (standard deviation / average value) × 100%), which indicates the variation in particle size, is not particularly limited, but is preferably 20% or less. The average particle size is determined by taking electron micrographs using a scanning electron microscope (SEM) to measure the cross-sectional areas of a sufficient number of particles, and calculating the diameter of the circle when each measurement value is taken as the area of ​​the circle. In this embodiment, the average particle size is defined as the arithmetic mean of the particle sizes of 1,000 particles. The coefficient of variation is also a value calculated from the particle size distribution of 1,000 particles.

[0028] An example of the procedure for preparing a reference object using fluorescent substance-encapsulated nanoparticles is shown below. Here, the reference object is prepared by immobilizing biotin, reacting the fluorescent substance-encapsulated nanoparticles with biotin, and then encapsulating the nanoparticles.

[0029] (Biotin fixation) A biotin solution (NHS-PEG-Biotin, Thermo Fisher Scientific) of a predetermined concentration was dropped onto a water-repellent printed 24-well glass slide (Matsunami Glass Industrial Co., Ltd.) and allowed to stand for 4 hours at 4°C to immobilize biotin on each well. The biotin-containing compound may have a silane functional group or an alkyl chain linker. Each well was then washed with a buffer solution containing trisaminomethane, and a buffer solution containing bovine serum albumin (BSA) was dropped into each washed well and allowed to stand for 15 minutes to perform blocking.

[0030] (Reaction of fluorescent substance-encapsulated nanoparticles with biotin) A 30 pmol / L suspension of streptavidin-modified fluorescent substance-containing nanoparticles is dropped into each well and left to stand for 2 hours at 25°C to allow the fluorescent substance-containing nanoparticles to react with the biotin on each well. Next, excess fluorescent substance-containing nanoparticles are washed away with phosphate buffer solution.

[0031] (Encapsulation operation) The glass slide is immersed in a container containing purified water to wash off the phosphate buffer solution. The glass slide is then immersed in a container containing ethanol, followed by a container containing xylene. Marinol is then applied to the glass slide as a mounting medium, and a cover glass is placed on the glass slide for mounting. A water-based mounting medium containing glycerin, polyvinyl alcohol, or the like may also be used.

[0032] The type of color proofing chart is not particularly limited, and any known chart can be used.

[0033] There is no particular limitation on the method for setting a reference exposure amount for a reference object. Fig. 2 is a flowchart showing an example of a method for setting a reference exposure amount. As shown in Fig. 2, the method for setting a reference exposure amount includes, for example, a step of photographing a reference object while gradually changing the exposure amount in an imaging device (step S111), a step of acquiring an output value of the photographed image (step S112), a step of determining whether the output value is within a desired range (step S113), and a step of determining a reference exposure amount (step S114).

[0034] In the step of photographing a reference object while gradually changing the exposure amount (step S111), the reference object is photographed while gradually changing the exposure amount. In step S111, one reference object may be photographed while gradually changing the exposure amount, or multiple reference objects may be prepared according to the respective exposure amounts, and each reference object may be photographed.

[0035] In the step of acquiring output values ​​of the captured images (step S112), output values ​​of each captured image obtained in step S111 are acquired. The method of acquiring the output values ​​is not particularly limited, and any known image analysis method can be used.

[0036] In the step of determining whether the output values ​​are within the desired range (step S113), it is determined whether the output values ​​obtained in step S112 are within the desired range. If none of the obtained output values ​​are within the desired range, the process returns to step S111, and photographing is performed again while changing the exposure amount. If any of the obtained output values ​​are within the desired range, the process proceeds to step S114.

[0037] In the step of determining the reference exposure amount (step S114), the exposure amount when an image is captured that falls within a desired range, among the output values ​​obtained in step S112, is determined as the reference exposure amount.

[0038] The method for calculating the exposure dose is not particularly limited. For example, the exposure dose can be calculated by measuring the exposure intensity of the light source using an optical power meter (main body: 8230, sensor: 82313B, manufactured by ADC Corporation) and multiplying the obtained exposure intensity by the exposure time.

[0039] As described above, the state of the light source of the photographing device changes due to deterioration over time, so even if the photographing device is set to match the reference exposure amount, the actual exposure amount will differ from the reference exposure amount. In this embodiment, the first exposure amount refers to the actual exposure amount. The first exposure amount is, for example, the actual exposure amount set in the photographing device by adjusting the exposure intensity or exposure time to match the reference exposure amount.

[0040] The first correction coefficient γ represents the degree of fluctuation in the state of the imaging device and is obtained using the reference exposure amount and the first exposure amount. The method for obtaining the first correction coefficient γ is not particularly limited. For example, the first correction coefficient γ can be obtained based on the output value α0 of the image of the reference object photographed at the reference exposure amount and the output value α1 of the image of the reference object photographed at the first exposure amount. In this case, the first correction coefficient γ may be the ratio of the output value α1 to the output value α0, or the difference between the output values ​​α0 and α1. In this embodiment, the ratio of the output value α1 to the output value α0 is defined as the first correction coefficient γ.

[0041] The type of output value is not particularly limited. For example, the output value α0 and the output value α1 may both be the average value of pixel values ​​of the image of the reference object, or the maximum value of pixel values. The method for acquiring the output value α0 and the output value α1 is not particularly limited, and a known image analysis method can be used.

[0042] Table 1 shows an example in which a reference object was actually photographed at a reference exposure and a first exposure, and output values ​​α0 and α1 of the photographed image at each exposure were obtained to obtain the first correction coefficient γ. The photographing device used was a hole slide scanner (NanoZoomer S60, Hamamatsu Photonics K.K.) equipped with an imaging sensor (Orca Flash 4.0, Hamamatsu Photonics K.K.), an objective lens (20x NA0.75, Olympus Corporation), and a fluorescent filter (64HE filter set, Carl Zeiss). A fluorescent plate (red, Microscopy & Education) was used as the reference object, and the output values ​​α0 and α1 were the average pixel values ​​obtained using the image analysis software ImageJ.

[0043] [Table 1]

[0044] The reference exposure amount and the first exposure amount may be photographing exposure amounts for different devices. In this case, even if the state of the photographing device changes due to the difference between the device photographing the reference object at the reference exposure amount and the device photographing the reference object at the first exposure amount, the photographing exposure amount, which will be described later, can be corrected using the first correction coefficient γ.

[0045] When a reference object is prepared using the fluorescent substance-encapsulated nanoparticles described above, as shown in Figures 3A-E, the number of fluorescent bright spots A in the reference object increases and the fluorescence intensity increases as the biotin concentration increases (from 0.00001 mM to 0.1 mM). Therefore, a calibration curve showing the relationship between biotin concentration and the output value of an image of the reference object captured at a reference exposure may be prepared, and the output value α0 of the reference object at a predetermined biotin concentration may be determined using the calibration curve. Assuming that the calibration curve passes through the origin, the number of images of the reference object taken when preparing the calibration curve is not particularly limited as long as it is one or more. However, it is preferable to take multiple images in order to prepare a more accurate calibration curve.

[0046] Furthermore, a calibration curve may be further created that represents the relationship between the biotin concentration and the output value of the captured image of the reference object at the first exposure amount. In this case, the ratio of the slope of the calibration curve at the first exposure amount to the slope of the calibration curve at the reference exposure amount may be set as a first correction coefficient γ. This makes it possible to correct the capture exposure amount (described later) using the correction coefficient γ even if the state of the capture device varies due to differences between the device that captures the reference object at the reference exposure amount and the device that captures the reference object at the first exposure amount.

[0047] 1-1-2. Step of determining target exposure for the object to be photographed (step S120) In this step, the first correction coefficient γ is used to correct the exposure amount arbitrarily set for the object to be photographed, and a target exposure amount for the object to be photographed is determined.

[0048] The photographic subject is an object that is actually photographed by the photographing device. The type of photographic subject is not particularly limited, and may be, for example, a cell or a tissue slice. These may contain a fluorescent substance or may be stained with a dye. The photographic subject may also emit autofluorescence.

[0049] When the object to be photographed contains a fluorescent substance, the type of fluorescent substance is not particularly limited. For example, the fluorescent substance may be a fluorescent organic dye or the above-mentioned quantum dots (semiconductor particles). The object to be photographed may be labeled with the above-mentioned fluorescent substance-containing nanoparticles. It is preferable that the fluorescent substance emits fluorescence with a wavelength of 400 to 1100 nm when excited by light with a wavelength of 200 to 700 nm.

[0050] Examples of fluorescent organic dyes include fluorescein-based dye molecules, rhodamine-based dye molecules, AlexaFluor (Invitrogen)-based dye molecules, BODIPY (Invitrogen)-based dye molecules, cascade-based dye molecules, coumarin-based dye molecules, eosin-based dye molecules, NBD-based dye molecules, pyrene-based dye molecules, Texas Red-based dye molecules, and cyanine-based dye molecules. Specific examples of fluorescent organic dyes include 5-carboxy-fluorescein, 6-carboxy-fluorescein, 5,6-dicarboxy-fluorescein, 6-carboxy-2',4,4',5',7,7'-hexachlorofluorescein, 6-carboxy-2',4,7,7'-tetrachlorofluorescein, 6-carboxy-4',5'-dichloro-2',7'-dimethoxyfluorescein, naphthofluorescein, 5-carboxy-rhodamine, 6-carboxy-rhodamine, 5,6-dicarboxy-rhodamine, rhodamine 6G, tetramethylrhodamine, X-rhodamine, AlexaFluor 350, AlexaFluor 405, AlexaFluor 430, AlexaFluor 488, AlexaFluor 500, AlexaFluor 514, AlexaFluor 516, AlexaFluor 518, AlexaFluor 519, AlexaFluor 520, AlexaFluor 521, AlexaFluor 522, AlexaFluor 523, AlexaFluor 524, AlexaFluor 525, AlexaFluor 526, AlexaFluor 527, AlexaFluor 528, AlexaFluor 529, AlexaFluor 530, AlexaFluor 531, AlexaFluor 532, AlexaFluor 533, AlexaFluor 534, AlexaFluor 535, AlexaFluor 536, AlexaFluor 537, AlexaFluor 538, AlexaFluor 539, AlexaFluor 540, AlexaFluor 541, AlexaFluor 542, AlexaFluor 543, AlexaFluor 544, AlexaFluor 545, AlexaFluor 546, AlexaFluor 547, AlexaFluor 548, AlexaFluor 549, AlexaFluor 549, AlexaFluor 549, AlexaFluor Examples of fluorescent organic dyes include uor532, AlexaFluor546, AlexaFluor555, AlexaFluor568, AlexaFluor594, AlexaFluor610, AlexaFluor633, AlexaFluor635, AlexaFluor647, AlexaFluor660, AlexaFluor680, AlexaFluor700, AlexaFluor750, BODIPYFL, BODIPYTMR, BODIPY493 / 503, BODIPY530 / 550, BODIPY558 / 568, BODIPY564 / 570, BODIPY576 / 589, BODIPY581 / 591, BODIPY630 / 650, BODIPY650 / 665, methoxycoumarin, eosin, NBD, pyrene, Cy5, Cy5.5, and Cy7. These fluorescent organic dyes may be used alone or in combination.

[0051] The method for incorporating a fluorescent substance into the object to be photographed is not particularly limited and can be appropriately selected from known methods. For example, a capture substance labeled with a fluorescent substance or fluorescent substance-containing nanoparticles can be specifically bound to a target substance in the object to be photographed. Examples of capture substances include antibodies. The method for binding a fluorescent substance or fluorescent substance-containing nanoparticles to a capture substance is not particularly limited and can be appropriately selected from known methods.

[0052] When the object to be photographed contains a fluorescent substance and the reference object is a fluorescent particle, it is preferable that the fluorescent substance and the fluorescent particle have the same light-emitting characteristics, which allows the object to be photographed more accurately and the photographed image to be corrected more accurately.

[0053] The type of dye is not particularly limited and can be appropriately selected from known dyes used to stain objects to be photographed. Examples of dyes include hematoxylin, eosin, etc. The method for staining the object to be photographed is not particularly limited and can be appropriately selected from known staining methods depending on the type of dye.

[0054] The type of material that emits autofluorescence within the object being photographed is not particularly limited, and examples include intracellular organelles such as mitochondria and lysosomes, extracellular matrices such as collagen and elastin, and cyclic compounds of flavins such as NADH and riboflavin.

[0055] The exposure amount for photography is an exposure amount that is arbitrarily set for the object to be photographed, or may be an exposure amount that is empirically determined for the object to be photographed.

[0056] The method for setting the exposure amount for photography is not particularly limited. Fig. 4 is a flowchart showing an example of a method for setting the exposure amount for photography. As shown in Fig. 4, the method for determining the exposure amount for photography includes, for example, a step of photographing an object while gradually changing the exposure amount in a photography device (step S121), a step of acquiring an output value of the photographed image (step S122), a step of determining whether the output value is within a desired range (step S123), and a step of determining the exposure amount for photography (step S124).

[0057] In the step of photographing an object while gradually changing the exposure amount (step S121), the object is photographed while gradually changing the exposure amount. In step S121, one object may be photographed while gradually changing the exposure amount, or multiple objects may be prepared according to the respective exposure amounts, and each object may be photographed.

[0058] In the step of acquiring output values ​​of the captured images (step S122), output values ​​are acquired for each captured image obtained in step S121. The method for acquiring the output values ​​is not particularly limited, and any known image analysis method can be used.

[0059] In the step of determining whether the output values ​​are within the desired range (step S123), it is determined whether the output values ​​obtained in step S122 are within the desired range. If none of the obtained output values ​​are within the desired range, the process returns to step S121, and photographing is performed again while changing the exposure amount. If any of the obtained output values ​​are within the desired range, the process proceeds to step S124.

[0060] In the step of determining the exposure amount for photography (step S124), the exposure amount when a photographed image is photographed that falls within the desired range among the output values ​​obtained in step S122 is determined as the exposure amount for photography. If none of the obtained output values ​​falls within the desired range, the step of photographing while changing the exposure amount (step S121) is performed.

[0061] When the object to be photographed contains a fluorescent substance, the exposure amount at which one bright spot can be recognized in the image may be set as the photographing exposure amount. When the object to be photographed is a cell and the photographing device automatically recognizes the cell nucleus or cell membrane in a bright field, the exposure amount at which the recognition rate is highest may be set as the photographing exposure amount.

[0062] From the viewpoint of more accurately correcting the exposure amount for photography by reflecting fluctuations in the photography device due to deterioration of the light source over time, it is preferable to set the exposure amount for photography in parallel with the setting of the reference exposure amount at approximately the same time.

[0063] The method of correcting the exposure amount for shooting and determining the target exposure amount for the object to be shot is not particularly limited as long as it uses the first correction coefficient γ. The target exposure amount can be determined, for example, by multiplying the exposure amount for shooting by the first correction coefficient γ. The target exposure amount can also be determined by adding the first correction coefficient γ to the exposure amount for shooting. By correcting the exposure amount for shooting using the first correction coefficient γ, it is possible to determine the exposure amount required to shoot the object to be shot even if the state of the shooting device changes due to aging of the light source, etc.

[0064] An example of a target exposure amount actually determined from the first correction coefficient γ and the exposure amount for photography is shown in Table 2. In this case, the exposure amount for photography is set for cultured cells.

[0065] [Table 2]

[0066] 1-1-3. Step of acquiring a photographed image of the photographed object (step S130) In this step, a photographed image of the object is obtained, photographed at a second exposure amount different from the target exposure amount.

[0067] The second exposure amount may be different from the target exposure amount, or may be the same as the target exposure amount. The second exposure amount is, for example, an exposure amount set by adjusting the exposure intensity or exposure time in the imaging device. In this embodiment, the second exposure amount is preferably one of the exposure amounts discretely set in the imaging device, and is an exposure amount set to match the target exposure amount.

[0068] The method for obtaining an image of the object photographed at the second exposure is not particularly limited, and the image may be obtained by photographing the object using the photographing device used to photograph the reference object, or the image may be obtained by photographing using a different photographing device that has a discretely set exposure amount and is different from the photographing device used to photograph the reference object.

[0069] 1-1-4. Step of obtaining second correction coefficient δ (step S140) In this step, a second correction coefficient δ that represents the difference between the second exposure amount and the target exposure amount is obtained based on the target exposure amount and the second exposure amount.

[0070] As mentioned above, in imaging devices with discrete exposure settings, the settable exposure is determined in steps, making it difficult to accurately set the exposure to the target exposure. For example, in a whole slide scanner (NanoZoomer S60, manufactured by Hamamatsu Photonics K.K.), the exposure can be adjusted by adjusting the exposure time, but as shown in Table 3, the exposure time is set discretely, making it difficult to accurately set the exposure to the target exposure.

[0071] [Table 3]

[0072] The second correction coefficient δ represents the difference between the second exposure and the target exposure that occurs in an imaging device in which the exposure is set discretely, and is used when correcting the captured image in the process of correcting the captured image (process S150) described below.

[0073] The method of obtaining the second correction coefficient δ is not particularly limited as long as it is obtained based on the target exposure amount and the second exposure amount. The ratio of the target exposure amount to the second exposure amount may be obtained as the second correction coefficient δ, or the difference between the second exposure amount and the target exposure amount may be obtained as the second correction coefficient δ.

[0074] This step may be performed in parallel with the step of acquiring a photographed image of the photographing object (step S130), or may be performed after step S130. In this embodiment, this step is performed in parallel with step S130.

[0075] Table 4 shows an example in which the second correction coefficient δ is actually obtained from the ratio of the target exposure dose to the second exposure dose.

[0076] [Table 4]

[0077] 1-1-5. Step of correcting the captured image (step S150) In this step, the captured image acquired in step S130 is corrected using the second correction coefficient δ.

[0078] By correcting the captured image of the object using the second correction coefficient δ, which represents the difference between the second exposure and the target exposure, the captured image can be made closer to the state of the image captured at the target exposure. This makes it possible to suppress a decrease in image analysis accuracy due to a difference between the target exposure for the object and the second exposure when actually capturing an image, even in an image capture device in which the exposure is set discretely.

[0079] The correction of the captured image may be performed by correcting the entire image or by correcting only specific regions. When the captured object contains fluorescent materials, the image may be subjected to threshold processing to extract bright spot regions, and only the extracted bright spot regions may be corrected. In this case, the bright spot regions may be extracted after correcting the entire image.

[0080] The method for correcting the captured image is not particularly limited. For example, the captured image can be corrected by multiplying the output value β of the captured image of the object acquired in step S130 by the second correction coefficient δ. Alternatively, the captured image can be captured by adding the second correction coefficient δ to the output value β of the captured image of the object. The output value β of the captured image of the object is, for example, the maximum pixel value or the average pixel value.

[0081] When the object contains fluorescent material, after obtaining the output value for each bright spot region, correction may be performed by multiplying each output value by the second correction coefficient δ, or by multiplying the average value of the output values ​​of the bright spot regions by the second correction coefficient δ. This makes it possible to prevent the increase in noise components in the image due to correction using the second correction coefficient δ.

[0082] An example of corrected image output values ​​obtained by photographing cultured cells and tissue slices containing fluorescent substances at the second exposure dose using the same equipment as that used in the step of obtaining the first correction coefficient γ and multiplying the output values ​​of the photographed images by the second correction coefficient δ is shown in Table 5. In this case, the average value of the pixel values ​​in the bright spot area was used as the output value of the photographed image.

[0083] [Table 5]

[0084] If the object being photographed contains fluorescent substances, and if the sensor noise and autofluorescence noise are sufficiently low, the entire image can be corrected without extracting the bright spot area. This eliminates the need to extract the fluorescent spot, making it easier to correct the photographed image. Figure 5 shows an image of a breast cancer tissue section labeled with a fluorescent substance. B in Figure 5 is a fluorescent spot. Because the sensor noise and autofluorescence noise in the image shown in Figure 5 are sufficiently low, the average pixel value for the entire image was multiplied by the second correction coefficient δ. The resulting corrected pixel values ​​are shown in Table 6.

[0085] [Table 6]

[0086] Fig. 6 shows a captured image of cells that emit autofluorescence. In Fig. 6, C represents a fluorescent spot, and D represents an autofluorescence region. When the object to be captured emits autofluorescence, such as the cells in Fig. 6, the image data correction method of this embodiment may further include a step of calculating the autofluorescence intensity of the object to be captured (step S160), and a step of determining a correction method for the captured image based on the calculated autofluorescence intensity (step S170).

[0087] 1-1-6. Step of calculating autofluorescence intensity of photographed object (step S160) In this step, the autofluorescence intensity of the object to be photographed is calculated.

[0088] The autofluorescence intensity can be, for example, the pixel value in the background region (autofluorescence region) in the captured image. The method for calculating the autofluorescence intensity is not particularly limited, and known image analysis methods can be used.

[0089] 1-1-7. Step of determining a correction method for the captured image (step S170) In this step, a correction method for the captured image is determined based on the calculated autofluorescence intensity.

[0090] When the object to be photographed emits autofluorescence, correcting the entire photographed image of the object using the second correction coefficient δ results in the output value derived from the autofluorescence being corrected at the same time, which increases noise.

[0091] Therefore, in this step, the autofluorescence intensity calculated in step S160 is compared with an arbitrarily set threshold value to determine a correction method for the captured image. Specifically, if the autofluorescence intensity is less than the threshold value, it is determined that the entire captured image should be corrected using the second correction coefficient δ. If the autofluorescence intensity is greater than the threshold value, it is determined that bright spot regions should be extracted and corrected using the second correction coefficient δ. This allows the captured image to be corrected more accurately according to the autofluorescence intensity. Then, in step S150, the captured image is corrected based on the method determined in this step.

[0092] 1-2.Image data correction device An image data correction device according to the first embodiment of the present invention that can be used when implementing the above image data correction method will be described.

[0093] The image data correction device according to the first embodiment is an image data correction device that corrects an image captured by a photographing device in which an exposure amount is discretely set, and includes: a first correction coefficient acquisition unit that acquires a first correction coefficient γ that represents a degree of fluctuation in the state of the photographing device, using an arbitrarily set reference exposure amount and a first exposure amount that is an actual exposure amount when the photographing device is set to match the reference exposure amount; a target exposure amount determination unit that uses the first correction coefficient γ to correct the photographing exposure amount that is arbitrarily set for a photographing object and determines a target exposure amount for the photographing object; an image acquisition unit that acquires a photographed image of the photographing object that was photographed at a second exposure amount that is different from the target exposure amount; a second correction coefficient acquisition unit that acquires a second correction coefficient that represents a difference between the second exposure amount and the target exposure amount, based on the target exposure amount and the second exposure amount; and a correction unit that corrects the acquired photographed image using the second correction coefficient δ.

[0094] 7 is a block diagram showing a schematic functional configuration of image data correction device 100 according to Embodiment 1. Image data correction device 100 has input section 10, control section 20, image acquisition section 30, operation section 40, display section 50, and storage section 60.

[0095] The input unit 10 inputs information relating to an arbitrarily set reference exposure amount and a first exposure amount, which is the actual exposure amount when the image capturing device is set to match the reference exposure amount. The input unit 10 may input measured values ​​of the reference exposure amount and the first exposure amount, or may input an output value α0 of an image of a reference object captured at the reference exposure amount and an output value α1 of an image of the reference object captured at the first exposure amount.

[0096] 8 is a block diagram showing a schematic functional configuration of control unit 20. Control unit 20 has a CPU (Central Processing Unit), RAM (Random Access Memory), etc., and executes various processes in cooperation with various programs stored in storage unit 60, thereby providing overall control of the operation of image data correction device 100. As shown in FIG. 8, control unit 20 also has a first correction coefficient acquisition unit 21, a target exposure amount determination unit 22, a second correction coefficient acquisition unit 23, and a correction unit 24. Control unit 20 functions as first correction coefficient acquisition unit 21, target exposure amount determination unit 22, second correction coefficient acquisition unit 23, and correction unit 24 in cooperation with the image processing programs stored in storage unit 60, and performs image correction.

[0097] The first correction coefficient acquisition unit 21 acquires the first correction coefficient γ using information related to the reference exposure amount and the shooting exposure amount input by the input unit 10. The method for acquiring the first correction coefficient γ is not particularly limited. For example, the first correction coefficient γ can be acquired based on the output value α0 of the image of the reference object captured at the reference exposure amount and the output value α1 of the image of the reference object captured at the first exposure amount. In this case, the ratio of the output value α1 to the output value α0 may be set as the first correction coefficient γ, or the difference between the output values ​​α0 and α1 may be set as the first correction coefficient γ. In this embodiment, the ratio of the output value α1 to the output value α0 is set as the first correction coefficient γ.

[0098] The target exposure determination unit 22 corrects the shooting exposure arbitrarily set for the shooting object using the first correction coefficient γ acquired by the first correction coefficient acquisition unit 21, and determines the target exposure for the shooting object. The method of correcting the shooting exposure and determining the target exposure for the shooting object is not particularly limited as long as it uses the first correction coefficient γ. The target exposure can be determined, for example, by multiplying the shooting exposure by the first correction coefficient γ. Alternatively, the target exposure can be determined by adding the first correction coefficient γ to the shooting exposure.

[0099] The second correction coefficient acquisition unit 23 acquires a second correction coefficient δ that represents the difference between the target exposure amount and the second exposure amount, based on the target exposure amount determined by the target exposure amount determination unit 22 and a second exposure amount that differs from the target exposure amount. The method for acquiring the second correction coefficient δ is not particularly limited as long as it is based on the target exposure amount and the second exposure amount, and the ratio of the target exposure amount to the second exposure amount may be acquired as the second correction coefficient δ, or the difference between the second exposure amount and the target exposure amount may be acquired as the second correction coefficient δ.

[0100] The correction unit 24 corrects the captured image acquired by the image acquisition unit (described later) using the second correction coefficient δ acquired by the second correction coefficient acquisition unit 23. The method of correcting the captured image is not particularly limited. For example, the captured image can be corrected by multiplying the output value β of the captured image of the object acquired by the image acquisition unit 30 by the second correction coefficient δ. Alternatively, the captured image can be corrected by adding the second correction coefficient δ to the output value β of the captured image.

[0101] The image acquisition unit 30 acquires a captured image of the object captured with the second exposure. Fig. 9 is a block diagram showing a schematic functional configuration of the image acquisition unit 30. As shown in Fig. 9, the image acquisition unit 30 may include a captured image input unit 31 and an output value acquisition unit 32.

[0102] The captured image input unit 31 inputs a captured image of the object captured at the second exposure. The image input unit 31 is, for example, a capturing device such as a fluorescent microscope or a whole slide scanner. The image input unit 31 may input image information sent from an external device (for example, the above-mentioned capturing device) or image information stored in a storage medium.

[0103] When the first correction coefficient γ is obtained using the captured images of the reference object captured at the reference exposure amount and the first exposure amount, the captured images of the reference object may be input from the captured image input unit 31.

[0104] The output value acquisition unit 32 acquires, by image analysis, the output value β of the captured image input by the image input unit 31. The output value β may be the average value of pixel values ​​or the maximum value of pixel values.

[0105] The operation unit 40 has, for example, a keyboard including character input keys, number input keys, various function keys, etc., and a pointing device such as a mouse, and outputs a press signal of a key pressed on the keyboard and an operation signal from the pointing device as input signals to the control unit 20.

[0106] The display unit 50 is configured to include a monitor such as an organic EL or LCD (Liquid Crystal Display), and displays various screens according to instructions of a display signal input from the control unit 20.

[0107] Image data correction device 100 may be configured to include a LAN adapter, a router, or the like, and to be connected to external devices via a communication network such as a LAN.

[0108] The storage unit 60 is configured, for example, by an HDD (Hard Disk Drive), a semiconductor nonvolatile memory, etc. The storage unit 60 stores various programs and various data, etc., as described above.

[0109] The image data correction device 100 having the above configuration can implement the image data correction method.

[0110] 1-3.Effects The image data correction method and image data correction device according to embodiment 1 can correct captured images in a photographing device in which the exposure amount is discretely set, taking into consideration not only fluctuations in the state of the photographing device but also the discrepancy between the exposure amount set in the photographing device and the target exposure amount.

[0111] 2. Second Embodiment 2-1. Image data correction method FIG. 10 is a flowchart of an image data correcting method according to the second embodiment.

[0112] 10, the image data correction method according to the second embodiment differs from that according to the first embodiment in that it further includes (1) a step of determining whether to determine a target exposure (step S210) and (2) a step of determining whether to correct the captured image (step S220). These steps will be described below.

[0113] 2-1-1. Step of Determining Whether to Determine Target Exposure Amount (Step S210) In this step, it is determined whether or not to determine the target exposure amount based on the value of the first correction coefficient γ acquired in the step of acquiring the first correction coefficient γ (step S110).

[0114] The method for determining whether to determine the target exposure amount is not particularly limited. For example, a reference value may be set in advance for the first correction coefficient γ, and if the difference between the value of the first correction coefficient γ obtained in step S110 and the reference value is equal to or greater than a certain value, it may be determined that the target exposure amount is to be determined.

[0115] 10, in this embodiment, the step of determining a target exposure amount (step S120) is performed when it is determined in this step that a target exposure amount should be determined. If it is determined in this step that a target exposure amount should not be determined, a step of acquiring a photographed image of the object photographed at the photographing exposure amount (step S230) is performed instead of the step of acquiring a photographed image (step S130), the step of acquiring a second correction coefficient δ (step S140), and the step of correcting the photographed image (step S150).

[0116] In the step of acquiring an image of the object photographed at a photographing exposure (step S230), an image of the object photographed at a photographing exposure that is an exposure arbitrarily set for the object is acquired. The photographing exposure is the same as that described in the first embodiment, and therefore a detailed description thereof will be omitted.

[0117] 2-1-2. Step of determining whether or not to correct the captured image (step S220) In this step, it is determined whether or not to correct the captured image based on the value of the second correction coefficient δ acquired in the step of acquiring the second correction coefficient δ (step S140).

[0118] The method for determining whether to correct the captured image is not particularly limited. For example, a reference value may be set in advance for the second correction coefficient δ, and if the difference between the value of the second correction coefficient δ acquired in step S140 and the reference value is equal to or greater than a certain value, it may be determined that the captured image is to be corrected.

[0119] 10, in this embodiment, the step of correcting the captured image (step S150) is performed when it is determined in this step that the captured image should be corrected. When it is determined in this step that the captured image should not be corrected, the step of correcting the captured image is not performed.

[0120] When the object to be photographed emits autofluorescence, the image data correction method of this embodiment may further include a step of calculating the autofluorescence intensity of the object to be photographed (step S160) and a step of determining a correction method for the photographed image based on the calculated autofluorescence intensity (step S170). When the image data correction method of this embodiment includes steps S160 and S170, steps S160 and S170 are performed between steps S140 and S150. These steps are the same as those described in embodiment 1, and therefore detailed description thereof will be omitted.

[0121] 2-2.Image data correction device Fig. 11 is a block diagram showing a schematic functional configuration of image data correction device 200 according to embodiment 2, and Fig. 12 is a block diagram showing a schematic functional configuration of control unit 20 of an image processing device according to embodiment 2. Image data correction device 200 according to embodiment 2 differs from image data correction device 100 according to embodiment 1 in that control unit 20 further includes target exposure amount determination and judgment unit 25 and captured image correction judgment unit 26. Unless otherwise specified, the same components as those in image data correction device 100 according to embodiment 1 are denoted by the same reference numerals and description thereof will be omitted.

[0122] The target exposure amount determination judgment unit 25 judges whether or not to have the target exposure amount determination unit 22 determine the target exposure amount based on the value of the first correction coefficient γ acquired by the first correction coefficient acquisition unit 21. There are no particular limitations on the method for determining whether or not to have the target exposure amount determination unit determine the target exposure amount. For example, if the difference between a preset reference value of the first correction coefficient and the value of the first correction coefficient γ acquired by the first correction coefficient acquisition unit 21 is equal to or greater than a certain value, it may be judged that the target exposure amount determination unit should determine the target exposure amount.

[0123] The captured image correction determination unit 26 determines whether or not to cause the correction unit 24 to correct the captured image based on the value of the second correction coefficient δ acquired by the second correction coefficient acquisition unit 23. There are no particular limitations on the method for determining whether or not to cause the correction unit to correct the captured image. For example, if the difference between a preset reference value of the second correction coefficient δ and the value of the second correction coefficient δ acquired by the second correction coefficient acquisition unit 23 is equal to or greater than a certain value, the unit may determine to cause the correction unit to correct the captured image.

[0124] In this embodiment, the value of the first correction coefficient γ acquired by the first correction coefficient acquisition unit 21 and the value of the second correction coefficient δ acquired by the second correction coefficient acquisition unit may be displayed on the display unit 50 of the image data correction device 200. This makes it easier for the user to recognize the degree of fluctuation in the state of the photographing device and the difference between the target exposure amount and the second exposure amount.

[0125] 2-3.Effects In addition to the effects of the image data correction method and image data correction device according to Embodiment 1, the image data correction method and image data correction device according to Embodiment 2 can make it easier for the photographer to recognize the need to determine the target exposure and the need to correct the captured image. Therefore, the target exposure can be set and the captured image can be corrected only when necessary.

[0126] 3. Embodiment 3 3-1. Image data correction method 13, the image data correction method according to the third embodiment differs from that of the first embodiment in that it further includes a step (step S310) of determining whether or not there is an abnormality in the imaging device. This step will be described below.

[0127] 3-1-1. Step of determining whether or not there is an abnormality in the imaging device (step S310) In this step, the presence or absence of an abnormality in the imaging device is determined using the exposure intensity when the reference object is photographed and the output value α2 of the photographed image of the reference object photographed at the above exposure intensity. In this embodiment, this step is performed before the step of acquiring the first correction coefficient γ (step S110), but it may also be performed between the step of acquiring the first correction coefficient γ (step S110) and the step of determining the target exposure amount (step S120). Furthermore, if it is determined in this step that there is an abnormality in the imaging device, the steps after the step of determining the target exposure amount (step S120) are not performed.

[0128] The method for determining whether or not there is an abnormality in the imaging device is not particularly limited. For example, if the difference between the ratio of the exposure intensity when photographing the reference object, calculated on the reference date, to the output value of the photographed image photographed at that exposure intensity and the ratio on the measurement date is equal to or greater than a certain value, it can be determined that there is an abnormality in the imaging device. This makes it easier to determine changes in the condition of the imaging device due to deterioration of the light source or damage or dirt on optical components, allowing for earlier inspection and cleaning of the imaging device, and component replacement and repair. From the perspective of more accurately determining whether or not there is an abnormality in the imaging device, it is preferable that the exposure intensity when photographing the reference object on the measurement date be the actual exposure intensity when set to match the exposure intensity when photographing the reference object on the reference date.

[0129] This step may be performed between the step of determining the target exposure (step S120) and the step of acquiring the second correction coefficient (step S140). In this case, if it is determined in this step that there is an abnormality in the image capturing device, the steps after this step are not performed. As a result, for example, if it is determined that there is an abnormality in the image capturing device that captured the reference object, it can be determined that the captured image of the object captured using the image capturing device will not be used to correct the image data.

[0130] An example of an actual case in which a reference object was photographed on a day other than the reference date using a whole slide scanner (NanoZoomer S60, manufactured by Hamamatsu Photonics K.K.) and the presence or absence of an abnormality in the imaging device was determined is shown in Table 7. In the results in Table 7, if the difference between the ratio of the exposure intensity on the reference date to the output value of the photographed image of the reference object photographed at the above exposure intensity and the above ratio on the measurement date was 3.0% or more compared to the above ratio on the reference date, it was determined that there was an abnormality in the imaging device.

[0131] [Table 7]

[0132] Furthermore, a reference photographing device may be determined in advance, and when a reference object is photographed with another photographing device, the presence or absence of an abnormality in the other photographing device may be determined. Specifically, if the difference between the ratio of the exposure intensity when photographing the reference object in the reference photographing device to the output value of the photographed image of the reference object photographed at the exposure intensity and the ratio in the other photographing device is equal to or greater than a certain value, it may be determined that the other photographing device has an abnormality.

[0133] 3-2.Image data correction device Fig. 14 is a block diagram showing a schematic functional configuration of an image data correction device 300 according to the third embodiment, and Fig. 15 is a block diagram showing a schematic functional configuration of a control unit 20 of an image processing device according to the third embodiment. Image data correction device 300 according to the third embodiment differs from image data correction device 100 according to the first embodiment in that control unit 20 further includes an imaging device abnormality determination unit 27. Unless otherwise specified, the same components as those in image data correction device 100 according to the first embodiment will be assigned the same reference numerals and descriptions thereof will be omitted.

[0134] In this embodiment, the input unit 10 inputs information regarding an arbitrarily set reference exposure amount and a first exposure amount, which is the actual exposure amount when set to match the reference exposure amount in the above-mentioned photographing device, as well as the exposure intensity when photographing the reference object and the output value α2 of the photographed image at the above-mentioned exposure intensity.

[0135] The imaging device abnormality determination unit 27 determines whether or not there is an abnormality in the imaging device based on the exposure intensity when photographing the reference object and the output value α2 of the photographed image of the reference object photographed at the above exposure intensity. The method for determining whether or not there is an abnormality in the imaging device is not particularly limited. For example, the ratio of the exposure intensity when photographing the reference object, calculated on the reference date, to the output value of the photographed image of the reference object photographed at the above exposure intensity is recorded in the storage unit 60, and if the difference between the ratio recorded in the storage unit 60 and the ratio on the measurement date is equal to or greater than a certain value, it can be determined that there is an abnormality in the imaging device.

[0136] Furthermore, the imaging device abnormality determination unit 27 can record the ratio for a reference imaging device in the storage unit 60, and determine that there is an abnormality in the imaging device if the difference between the ratio recorded in the storage unit 60 and the ratio for another imaging device is equal to or greater than a certain value. When it is determined that there is an abnormality, the image data correction device 300 can display a message indicating that there is an abnormality on the display unit 50.

[0137] Effects In addition to the effects of the image data correction method and image data correction device of embodiment 3, the image data correction method and image data correction device of embodiment 3 can make it easier for the user to recognize whether or not there is an abnormality in the imaging device. [Industrial Applicability]

[0138] According to the present invention, it is possible to provide an image data correction method that can obtain more accurate captured image data even in an imaging device in which the exposure amount is set discretely. For example, the present invention is useful in pathological diagnosis. [Explanation of symbols]

[0139] 10 Input section 20 Control Unit 21 First correction coefficient acquisition unit 22 Target exposure amount determination section 23 Second correction coefficient acquisition unit 24 Correction unit 25 Target exposure amount determination and judgment unit 26. Image correction determination unit 27 Imaging device abnormality determination unit 30 Image acquisition unit 40 Control section 50 Display section 60 Storage section S110: Obtaining a first correction coefficient S120: Determining a target exposure amount S130: Acquiring a photographed image S140: Obtaining a second correction coefficient S150: A process for correcting captured images S160 Calculating autofluorescence intensity S170: Step of determining the correction method S210: A step of determining whether or not to determine a target exposure amount S220: A step of determining whether or not to correct the captured image S310: A step of determining whether or not there is an abnormality in the imaging device A, B, C fluorescent bright spots D Autofluorescence area

Claims

1. 1. An image data correction method for correcting an image captured by an image capture device in which an exposure amount is discretely set, comprising: obtaining a first correction coefficient γ representing a degree of fluctuation in the state of the photographing device, using an arbitrarily set reference exposure amount and a first exposure amount which is an actual exposure amount when set to match the reference exposure amount in the photographing device; a step of correcting a photography exposure amount set for photographing an object with the photographing device using the first correction coefficient γ, and determining a target exposure amount for photographing the object with the photographing device; acquiring a photographed image of the object photographed by the photographing device at a second exposure amount different from the target exposure amount; obtaining a second correction coefficient δ representing a difference between the second exposure amount and the target exposure amount based on the target exposure amount and the second exposure amount; correcting the acquired photographed image using the second correction coefficient δ; The exposure amount for photography is the exposure amount when a photographed image whose output value falls within a predetermined range is photographed among a plurality of photographed images obtained by photographing the photographic object at a plurality of levels of exposure amount. Image data correction method.

2. The step of acquiring the first correction coefficient γ includes: The output value α of the image of the reference object photographed at the reference exposure ０ and an output value α of the image of the reference object photographed with the first exposure amount. １ and obtaining The output value α ０ and the output value α １ calculating the first correction coefficient γ based on the The method of claim 1 , further comprising:

3. The output value α ０ and the output value α １ 3. The image data correction method according to claim 2, wherein each of the pixel values ​​of the image of the reference object is an average value of the pixel values ​​of the image of the reference object.

4. The output value α ０ and the output value α １ and are the maximum pixel values ​​of the image of the reference object.

5. 5. The image data correction method according to claim 2, wherein the reference object is a fluorescent plate.

6. 5. The image data correction method according to claim 2, wherein the reference object is a fluorescent particle.

7. the object to be photographed contains a fluorescent substance, The fluorescent particles have the same luminescent properties as the fluorescent material. The image data correction method according to claim 6.

8. 5. The image data correcting method according to claim 2, wherein the reference object is a color calibration chart.

9. 9. The image data correction method according to claim 1, wherein in the step of correcting the captured image, the captured image is corrected by multiplying the output value β of the captured image by the second correction coefficient δ.

10. The method further includes a step of determining whether or not to determine the target exposure amount based on the value of the first correction coefficient γ acquired in the step of acquiring the value of the first correction coefficient γ, the step of determining the target exposure amount is performed when it is determined that the target exposure amount is to be determined in the step of determining whether to determine the target exposure amount; When it is determined that the target exposure should not be determined in the step of determining whether to determine the target exposure, a step of acquiring a photographed image of the object photographed at the photographing exposure is performed instead of the step of acquiring the photographed image, the step of acquiring the second correction coefficient δ, and the step of correcting the photographed image. The image data correction method according to any one of claims 1 to 9.

11. The method further includes a step of determining whether or not to correct the captured image based on the value of the second correction coefficient δ acquired in the step of acquiring the value of the second correction coefficient δ, the step of correcting the captured image is performed when it is determined in the step of determining correction of the captured image that the captured image should be corrected, and is not performed when it is determined that the captured image should not be corrected. The image data correction method according to any one of claims 1 to 10.

12. 9. The image data correction method according to claim 2, wherein the reference exposure amount and the first exposure amount are exposure amounts in different image capturing devices.

13. 13. The image data correction method according to claim 1, wherein the first exposure amount and the second exposure amount are set by adjusting exposure intensity or exposure time, respectively.

14. an exposure intensity when photographing the reference object, and an output value α of the photographed image of the reference object photographed at the exposure intensity; ２ The method further includes a step of determining whether or not there is an abnormality in the imaging device of the reference object using the The image data correction method according to any one of claims 2 to 8 and 12.

15. the object to be photographed emits autofluorescence, The image data correction method includes: calculating the autofluorescence intensity of the object; determining a correction method for the captured image based on the calculated autofluorescence intensity; The image data correction method according to any one of claims 1 to 7 and 9 to 14.

16. 1. An image data correction device for correcting an image captured by a photographing device in which an exposure amount is discretely set, comprising: a first correction coefficient acquisition unit that acquires a first correction coefficient γ representing a degree of fluctuation in a state of the photographing device, using an arbitrarily set reference exposure amount and a first exposure amount that is an actual exposure amount when set to match the reference exposure amount in the photographing device; a target exposure amount determination unit that corrects a shooting exposure amount set for photographing an object with the photographing device using the first correction coefficient γ and determines a target exposure amount for photographing the object with the photographing device; an image acquisition unit that acquires a photographed image of the object photographed by the photographing device at a second exposure amount different from the target exposure amount; a second correction coefficient acquisition unit that acquires a second correction coefficient representing a difference between the second exposure amount and the target exposure amount based on the target exposure amount and the second exposure amount; a correction unit that corrects the acquired captured image using the second correction coefficient δ; and The exposure amount for photography is the exposure amount when a photographed image whose output value falls within a predetermined range is photographed among a plurality of photographed images obtained by photographing the photographic object at a plurality of levels of exposure amount. Image data correction device.

Images