Ophthalmologic apparatus, high dynamic range image generation method for ophthalmologic apparatus, and high dynamic range image generation program for ophthalmologic apparatus

Abstract

To generate an HDR image (high dynamic range image) without disturbance even when a subject blinks during image photographing.SOLUTION: A photographing unit 10 that photographs an eyeball image of a subject at a constant time interval for each of different exposure conditions, a storage unit 20 that stores the eyeball image together with photographing time information as photographing data and stores an eyeball image selected from the eyeball images of the photographing data as a reference image, and a calculation unit 50 that stores a copy of the reference image as an output image in the storage unit 20, performs HDR processing on the output image to generate an HDR image, and determines whether or not the eyeball image of the photographing data is the same as the reference image, when the calculation unit 50 determines that the eyeball image and the reference image are the same in chronological order of the photographing time information, the calculation unit 50 executes processing of superimposing the eyeball image on the output image to update the output image and storing the output image in the storage means 20 on the eyeball image under the same exposure condition to generate an HDR image.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ophthalmic apparatus, a high dynamic range image generation method for an ophthalmic apparatus, and a high dynamic range image generation program for an ophthalmic apparatus, and more particularly to an ophthalmic apparatus, a high dynamic range image generation method for an ophthalmic apparatus, and a high dynamic range image generation program for an ophthalmic apparatus that are capable of efficiently generating high dynamic range images from captured images. [Background technology]

[0002] A technique for generating high dynamic range images is used in various fields as a process for making images captured by a camera or the like look more similar to the human eye. A known method for generating such high dynamic range images is disclosed in Patent Document 1 (JP 2024-14009 A). Patent Document 1 discloses a technique for converting images used in an ophthalmic device into high dynamic range images. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2024-14009 A Summary of the Invention [Problem to be solved by the invention]

[0004] The ophthalmic device disclosed in Patent Document 1 generates a high dynamic range image by combining images captured by an imaging device, but it is assumed that the images captured by the imaging device are all the same except for the imaging conditions such as exposure time. However, when capturing images in the ophthalmic device, an image taken at the moment of blinking may be included. It has become clear that generating a high dynamic range image using such mutually different images can cause problems such as distortion in the generated image. [Means for solving the problem]

[0005] Therefore, one object of the present invention is to provide an ophthalmic device, a high dynamic range image generation method for an ophthalmic device, and a high dynamic range image generation program for an ophthalmic device that are capable of generating a high dynamic range image without distortion even if the subject blinks during image capture.

[0006] As a result of intensive research by the present inventors to solve the above problems, the present invention has arrived at the following configuration: That is, the present invention comprises an imaging means for imaging a subject's eyeball image at a fixed time interval for each of different exposure conditions, a storage means for storing the subject's eyeball image together with information on the time of imaging as imaging data, and storing the subject's eyeball image selected from the subject's eyeball images in the imaging data as a reference image based on the similarity with a reference image for selecting a reference image or by an examiner, an output image initialization means for storing a copy of the reference image as an output image in the storage means, a high dynamic range image generation means for performing high dynamic range processing on the output image to generate a high dynamic range image, and a storage means for storing the imaging data together with information on the time of imaging as a reference image. and an image similarity determination means for determining whether the subject's eye image in the output is the same as the reference image, and the high dynamic range image generation means is characterized in that the image similarity determination means compares the similarity between the subject's eye image and the reference image in chronological order of the shooting time information, and only when it determines that the subject's eye image and the reference image are the same, performs a process on the subject's eye image under the same exposure conditions to overlay the subject's eye image on the output image, update the output image, and store it in the storage means, thereby generating the high dynamic range image.

[0007] This makes it possible to generate a clear, high dynamic range image even if the subject blinks during image capture.

[0008] Furthermore, the high dynamic range image generating means executes a process of continuing to use the output image when a difference between the shooting time information when the image similarity / difference determining means first determined that the subject's eyeball image is different from the reference image and the shooting time information when the image similarity / difference determining means determined that the subject's eyeball image has returned to the reference image is within a first threshold value set in advance, and If the difference between the photographing time information when it is determined that the subject's eyeball has been photographed exceeds the first threshold value set in advance, it is preferable to perform the following processes: causing the photographing means to photograph the subject's eyeball image again; causing the re-photographed subject's eyeball image to be stored in the storage means as the photographing data together with the photographing time information; causing the storage means to store the subject's eyeball image selected from the subject's eyeball images in the photographing data as the reference image; and causing the output image initialization means to store a copy of the reference image in the storage means as the output image.

[0009] As a result, when the image change is due to blinking, which is a physiological phenomenon, the images before and after the image change are often almost identical, so the image data before the image change can be used without being discarded.

[0010] Furthermore, it is preferable that the image similarity judgment means performs the following processes: dividing the reference image, the subject's eye image, and the output image into a plurality of divided areas each having the same shape and the same arrangement; updating the output image by overlaying the divided areas in the subject's eye image on the divided areas in the output image when the difference in the numerical value for similarity judgment between each of the divided areas in the subject's eye image and the reference image that are in the same position is less than a predetermined second threshold; and maintaining the output image when the difference in the numerical value for similarity judgment between each of the divided areas in the subject's eye image and the reference image that are in the same position exceeds the second threshold.

[0011] This makes it possible to use data of portions where no image change has actually occurred, even if it is determined that an image change has occurred in the entire image.

[0012] Furthermore, it is preferable that the numerical value for determining similarity or difference is the average value of the values ​​or converted values ​​of each pixel in each of the divided areas, based on at least one of the RGB values ​​(R value, G value, B value) of each pixel of the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

[0013] This reduces the data processing time required to determine whether the images are the same or different.

[0014] It is also preferable that the image display control means further comprises an image display control means for displaying at least one of the reference image and the output image on the image display unit, and that the image display control means displays the output image on the image display unit each time the output image is updated.

[0015] This allows the user to check the high dynamic range image while it is being generated.

[0016] Also, a high dynamic range image generating method for an ophthalmic apparatus used in an ophthalmic apparatus including an imaging means for capturing images of the eyeball of a subject, a storage means, and a calculation unit, comprising: a step in which the calculation unit causes the imaging means to capture images of the eyeball of the subject at regular time intervals under different exposure conditions; a step in which the calculation unit stores the eyeball images of the subject together with information on the time of capture as imaging data in the storage means; a step in which the calculation unit stores the eyeball images of the subject selected from the images of the subject's eyeball in the imaging data based on the similarity with a reference image for selecting a reference image or selected by an examiner as reference images in the storage means; a step in which the calculation unit stores a copy of the reference image as an output image in the storage means; and a step in which the calculation unit performs high dynamic range processing on the output image to generate a high dynamic range image. and a step of the calculation unit determining whether the subject's eye image in the shooting data is the same as the reference image, wherein the step of generating a high dynamic range image comprises the steps of: causing the calculation unit to compare the similarity between the subject's eye image and the reference image in chronological order of the shooting time information, and only if it is determined that the subject's eye image and the reference image are the same, causing the calculation unit to overlay the subject's eye image on the output image, update the output image, and store it in the storage means; and the step of comparing the similarity between the subject's eye image and the reference image in chronological order of the shooting time information, and if it is determined that the subject's eye image is different from the reference image, causing the calculation unit to maintain the output image.

[0017] This makes it possible to generate a clear, high dynamic range image even if the subject blinks during image capture.

[0018] It is also preferable that the method further comprises the steps of: continuing to use the output image when the calculation unit determines that the subject's eye image is different from the reference image and continuing to use the output image when the difference between the shooting time information when the calculation unit first determines that the subject's eye image is different from the reference image and the shooting time information when the calculation unit determines that the subject's eye image has returned to the reference image is within a predetermined first threshold; causing the photographing means to photograph the subject's eye image again when the difference between the shooting time information when the calculation unit first determines that the subject's eye image is different from the reference image and the shooting time information when the calculation unit determines that the subject's eye image has returned to the reference image exceeds the predetermined first threshold; storing the re-photographed subject's eye image together with the shooting time information in the memory means as the photographing data; storing a subject's eye image selected from the subject's eye images in the photographing data in the memory means as the reference image; and having the calculation unit store a copy of the reference image in the memory means as the output image.

[0019] As a result, when the image change is due to blinking, which is a physiological phenomenon, the images before and after the image change are often almost identical, so the image data before the image change can be used without being discarded.

[0020] It is also preferable that the calculation unit performs the following steps: dividing the reference image, the subject's eye image, and the output image into a plurality of divided areas each having the same shape and the same arrangement; updating the output image by overlaying the divided areas in the subject's eye image on the divided areas in the output image when the calculation unit determines that the difference in the numerical value for determining whether the same or different exists between the divided areas in the subject's eye image and the reference image, which are at the same position, is equal to or less than a predetermined second threshold; and maintaining the output image when the calculation unit determines that the difference in the numerical value for determining whether the same or different exists between the divided areas in the subject's eye image and the reference image, which are at the same position, exceeds the second threshold.

[0021] This makes it possible to use data of portions where no image change has actually occurred, even if it is determined that an image change has occurred in the entire image.

[0022] Furthermore, it is preferable that the calculation unit uses the average value of the values ​​or converted values ​​of each pixel in each divided area as the numerical value for determining whether or not the pixel is the same, based on either at least one value (R value, G value, B value) of the RGB values ​​of each pixel in the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

[0023] This reduces the data processing time required to determine whether the images are the same or different.

[0024] Furthermore, it is preferable that the ophthalmologic device further has an image display unit that displays at least one of the reference image and the output image, and an image display control means that causes at least one of the reference image and the output image to be displayed on the image display unit, and that the calculation unit has a step of displaying the output image on the image display unit each time the output image is updated.

[0025] This allows the user to check the high dynamic range image while it is being generated.

[0026] Further, a high dynamic range image generating program for an ophthalmic apparatus, which is used in an ophthalmic apparatus having an imaging means for capturing images of the eyeball of a subject, a storage means, and a calculation unit, includes the steps of: causing the imaging means to capture images of the eyeball of a subject at regular time intervals for each of different exposure conditions; storing the eyeball images of the subject together with information on the time of capture as imaging data in the storage means; selecting an eyeball image of the subject in the imaging data based on a similarity with a reference image for selecting a reference image or selecting an image by an examiner from the eyeball images of the subject in the imaging data; storing a copy of the reference image in the storage means as an output image; and performing high dynamic range processing on the output image to generate a high dynamic range image. and a process for determining whether the subject's eye image in the shooting data is the same as the reference image, wherein the high dynamic range image generation process includes a process for comparing the similarity between the subject's eye image and the reference image in chronological order of the shooting time information, and if it is determined that the subject's eye image and the reference image are the same, overlaying the subject's eye image on the output image, updating the output image, and storing it in the storage means; and a process for comparing the similarity between the subject's eye image and the reference image in chronological order of the shooting time information, and if it is determined that the subject's eye image is different from the reference image, maintaining the output image.

[0027] This makes it possible to generate a clear, high dynamic range image even if the subject blinks during image capture.

[0028] It is also preferable that the calculation unit executes the following processes: a process of continuing to use the output image if the difference between the shooting time information when it was first determined that the subject's eye image was different from the reference image and the shooting time information when it was determined that the subject's eye image had returned to the reference image is within a predetermined first threshold; a process of having the photographing means photograph the subject's eye image again if the difference between the shooting time information when it was first determined that the subject's eye image was different from the reference image and the shooting time information when it was determined that the subject's eye image had returned to the reference image exceeds the predetermined first threshold; a process of storing the re-photographed subject's eye image together with the shooting time information in the memory means as the photographing data; a process of storing a subject's eye image selected from the subject's eye images in the photographing data in the memory means as the reference image; and a process of storing a copy of the reference image in the memory means as the output image.

[0029] As a result, when the image change is due to blinking, which is a physiological phenomenon, the images before and after the image change are often almost identical, so the image data before the image change can be used without being discarded.

[0030] It is also preferable to have the calculation unit perform the following steps: a process of dividing the reference image, the subject's eye image, and the output image into a plurality of divided areas each having the same shape and the same arrangement; a process of overlaying the divided areas in the subject's eye image on the divided areas in the output image to update the output image when it is determined that the difference in the numerical value for determining whether the same or different exists between the divided areas in the subject's eye image and the reference image, which are in the same position, is equal to or less than a predetermined second threshold; and a process of maintaining the output image when it is determined that the difference in the numerical value for determining whether the same or different exists between the divided areas in the subject's eye image and the reference image, which are in the same position, exceeds the second threshold.

[0031] This makes it possible to use data of portions where no image change has actually occurred, even if it is determined that an image change has occurred in the entire image.

[0032] It is also preferable that the calculation unit uses the average value of the values ​​or converted values ​​of each pixel in each divided area as the numerical value for determining whether or not the pixel is the same, based on either at least one value (R value, G value, B value) of the RGB values ​​of each pixel in the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

[0033] This reduces the data processing time required to determine whether the images are the same or different.

[0034] In addition, it is preferable that the ophthalmologic device further has an image display unit that displays at least one of the reference image and the output image, and an image display control means that causes at least one of the reference image and the output image to be displayed on the image display unit, and that the calculation unit causes the output image to be displayed on the image display unit each time the output image is updated.

[0035] This allows the user to check the high dynamic range image while it is being generated. [Effects of the Invention]

[0036] According to the configurations of the ophthalmic device, the high dynamic range image generation method for the ophthalmic device, and the high dynamic range image generation program for the ophthalmic device of the present invention, it is possible to generate a high dynamic range image without distortion even if the subject blinks during image capture. [Brief explanation of the drawings]

[0037] [Figure 1] 1 is a schematic configuration diagram of an ophthalmologic apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a flowchart illustrating the overall processing of image data in the ophthalmologic apparatus according to the present embodiment. [Figure 3] FIG. 3 is a detailed flowchart of the initialization process in FIG. 2. [Figure 4] 10 is an explanatory diagram showing a specific example when a current image buffer N and a preceding image buffer B are divided by a change observation area AREA. FIG. [Figure 5] FIG. 3 is a detailed flow diagram of the imaging and data conversion process in FIG. 2. [Figure 6] FIG. 3 is a detailed flowchart of the high dynamic range image generation process in FIG. 2. [Figure 7] 10A and 10B are explanatory diagrams showing a specific example of a process for generating a high dynamic range image. [Figure 8] FIG. 7 is a detailed flowchart of a subroutine of the blink determination process in FIG. 6. [Figure 9] FIG. 10 is an explanatory diagram showing a specific example of blink determination processing. [Figure 10] FIG. 3 is a detailed flow diagram of the output screen update and imaging condition setting process in FIG. 2. [Figure 11] FIG. 2 is an explanatory diagram showing a specific example of shooting conditions (exposure conditions). DETAILED DESCRIPTION OF THE INVENTION

[0038] An embodiment of an ophthalmic apparatus 100 according to the present invention will be described below with reference to FIG. 1. The ophthalmic apparatus 100 in this embodiment includes an imaging unit 10, a storage unit 20, an image display unit 30, an external input / output unit 40, and a calculation unit 50. The calculation unit 50 controls the operations of the imaging unit 10, the storage unit 20, the image display unit 30, and the external input / output unit 40 based on an operation control program, including a high dynamic range image generation program, stored in the storage unit 20. Specifically, the calculation unit 50 performs the following processes: causes the imaging unit 10 to capture images of the subject's eye at regular intervals under different exposure conditions; causes the storage unit 20 to store the captured image data of the subject's eye; causes the calculation unit 50 to generate high dynamic range images based on the image data of the subject's eye stored in the storage unit 20; and causes the calculation unit 50 to output the generated high dynamic range images to the image display unit 30. Note that the period of time during which the imaging unit 10 captures images of the subject's eye at regular intervals varies depending on the imaging unit 10 actually used, but is preferably several seconds at 30 to 60 frames per second.

[0039] Next, the processing contents when the ophthalmic apparatus 100 of this embodiment converts a subject's eyeball image into a high dynamic range image will be described with reference to Fig. 2 etc. As shown in Fig. 2, the ophthalmic apparatus 100 of this embodiment performs four processes: initialization processing I, imaging and digitization processing P, high dynamic range processing H, and output screen update and imaging condition setting processing O. Furthermore, the imaging and digitization processing P, high dynamic range processing H, and output screen update and imaging condition setting processing O are repeatedly executed for each subject or examination item.

[0040] Next, specific processing contents of the initialization process I will be described with reference to Fig. 3. When the examiner starts up the ophthalmic apparatus 100, the calculation unit 50, which serves as initialization means, executes the initialization process I. Specifically, the calculation unit 50 checks (I-1) whether a camera, which is the image capture means 10, is connected via the external input / output unit 40, which is typified by a USB connection terminal of the ophthalmic apparatus 100, and if the image capture means 10 is connected, executes process (I-2) to initialize the image capture means 10 to a usable state. On the other hand, if the image capture means 10 is not connected during the process (I-1), it executes display process (I-3) on the image display unit 30 to confirm the connection of the image capture means 10, and then returns to process (I-1).

[0041] Next, the calculation unit 50 executes a process (I-4) of preparing various data to be stored in the storage means 20. Specifically, the calculation unit 50 executes a process of outputting to the image display unit 30 a screen prompting the user to input the values ​​of the first change amount threshold THR, the change observation area AREA, the area change threshold AREA_THR, the blink determination reference time T, and the second change amount threshold THR2. The values ​​of the first change amount threshold THR, the change observation area AREA, the area change threshold AREA_THR, and the blink determination reference time T input by the user from an input means (not shown) connected via the external input / output unit 40 are each stored in the storage means 20. The calculation unit 50 also executes a process of preparing in the storage means 20 a current image buffer N, a one-frame previous image buffer B, an output image buffer OUT, a reference value buffer Y, a current image capture time NT, a one-frame previous image capture time BT, a reference image buffer JB, reference image time data JBT, a change image buffer JP, and a change image capture time JPT. Furthermore, the calculation unit 50 executes a process of setting the photography restart flag to TRUE and storing it in the storage means 20.

[0042] Next, the examiner or the calculation unit 50 executes a process (I-5) for setting reference photographing conditions for the photographing means 10 for photographing an image of the subject's eyeball. Specifically, while displaying an image of the subject's eyeball photographed by the photographing means 10 on the image display unit 30, the calculation unit 50 sets the reference photographing conditions to the exposure conditions that are the lowest possible to prevent so-called blown-out highlights from occurring in the image of the subject's eyeball. The setting of the reference photographing conditions may be performed by the calculation unit 50 executing a process for setting appropriate reference photographing conditions based on a program for determining reference photographing conditions pre-stored in the storage unit 20 and the brightness and luminance of the image of the subject's eyeball photographed by the photographing means 10. After the reference photographing conditions are set, the calculation unit 50 executes a process (I-6) for causing the photographing means 10 to photograph an image of the subject's eyeball under the reference photographing conditions, sets the photographed image of the subject's eyeball as the reference image, and stores the reference image in the storage unit 20 as the output image buffer OUT.

[0043] Next, the calculation unit 50, which serves as the image similarity / difference determination means, executes a process (I-7) of dividing each of the current image buffer N and the one-frame-before-previous image buffer B into a grid based on the change observation area AREA stored in the storage means 20. The current image buffer N stores the subject's eyeball image (frame image) captured by the imaging means 10, while the one-frame-before-previous-image buffer B first stores a reference image (described later), followed by sequentially storing one-frame-before-previous frame images in the time series of the subject's eyeball image stored in the current image buffer N. As shown in FIG. 4, the calculation unit 50 divides each of the frame images stored in the current image buffer N and the one-frame-before-previous-image buffer B into a plurality of grids for each change observation area AREA. Furthermore, the calculation unit 50 assigns serial numbers to the grids in the next and subsequent rows, starting with the grid number 1 at the leftmost position in the top row and incrementing the numbers by 1 toward the rightmost grid. In FIG. 4, the portion surrounded by the solid line is the frame image, and the portion surrounded by the dashed line or the dashed and solid lines is the grid.

[0044] In this embodiment, the current image buffer N and the one-frame-before image buffer B are each divided into 20 grids of 4 rows and 5 columns as shown in Fig. 4, but the number of grid divisions is not particularly limited as long as it is a natural number. In this embodiment, the calculation unit 50 also executes a process of storing the number of grids as PART_NUM in the storage means 20. In this embodiment, the calculation unit 50 divides each of the current image buffer N and the one-frame-before image buffer B into grids of the same shape and arrangement based on the change observation area AREA, but the present invention is not limited to this form. It is also possible to adopt a configuration in which the calculation unit 50 divides each of the current image buffer N and the one-frame-previous image buffer B into a grid pattern of m rows and n columns based on image division data that has been stored in advance in the storage means 20 and is used to divide each of the current image buffer N and the one-frame-previous image buffer B into a grid pattern of m rows and n columns, or a configuration in which the calculation unit 50 prompts the measurer to input the number of image divisions (m, n) via data input means (not shown), and the calculation unit 50 divides each of the current image buffer N and the one-frame-previous image buffer B into a grid pattern of m rows and n columns based on the number of image divisions input by the measurer.

[0045] Next, the calculation unit 50 executes a process (I-8) of storing in the storage means 20 the reference average value N_AVE{PART_NUM} of each grid in the current image buffer N and the reference average value B_AVE{PART_NUM} of each grid (divided regions in the subject's eyeball image) in the one-frame-before image buffer B. The reference average value N_AVE{PART_NUM} of each grid in the current image buffer N can be the average value of the numerical values ​​of each pixel in each grid in the current image buffer N (RGB values, calculated values ​​calculated by substituting RGB values ​​into a predetermined formula, etc.; see FIG. 5). Similarly, the reference average value B_AVE{PART_NUM} of each grid in the one-frame-before image buffer B can be the average value of the numerical values ​​of each pixel in each grid in the one-frame-before image buffer B (RGB values, calculated values ​​calculated by substituting RGB values ​​into a predetermined formula, etc.; see (P-5) in FIG. 5).

[0046] Next, the calculation unit 50 executes a process (I-9) to clear (zero clear) each numerical value stored or prepared (secured) in the storage means 20 in the steps of the initialization process I to a preset value (preferably zero). This completes the initialization process I (initialization process end).

[0047] Next, specific processing contents of the photographing and data conversion process P will be described with reference to FIG. 5. The calculation unit 50 executes a process (P-1) of copying frame image data of a photographed image of the subject's eyeball stored in the current image buffer N to the immediately preceding image buffer B, and copying the current image photographing time NT to the immediately preceding image photographing time BT. Next, the calculation unit 50 executes a process (P-2) of photographing an image of the subject's eyeball using the photographing means 10 under the reference photographing conditions (see FIG. 11) set in the process (I-5) of setting the reference photographing conditions, storing frame image data of the photographed subject's eyeball image in the current image buffer N, and storing the current time in the storage means 20 as the current image photographing time NT. As described above, in this embodiment, the photographing data is composed of the subject's eyeball image, which is image data, and photographing time information (photographing time information) of the subject's eyeball image, and the subject's eyeball image and the photographing time information of the subject's eyeball image are stored in the storage means 20 as separate parameters.

[0048] Next, the calculation unit 50 checks whether the shooting restart flag is TRUE (P-3), and if the shooting restart flag is FALSE (No), executes processing (P-4) to copy the current image buffer N to the output image buffer OUT and set the shooting restart flag to FALSE. The calculation unit 50 calculates a reference value (converted value) based on a predetermined calculated value as a reference value used to determine whether images are similar or different for each pixel of the current image buffer N, and executes processing (P-5) to store the calculated reference value in the storage means 20 as a reference value buffer Y. In this embodiment, the RGB values ​​(R value, G value, B value) of each pixel of the frame image in the current image buffer N are substituted into the reference value calculation formula = 0.299 × R value + 0.587 × G value + 0.114 × B value to calculate the reference value for brightness. The reference value to be stored in the reference value buffer Y is not limited to the reference value related to luminance in this embodiment, but may be a reference value obtained by substituting at least one value of RGB values ​​(R value, G value, B value) directly or in a predetermined conversion formula. On the other hand, if the shooting restart flag is TRUE (Yes), the calculation unit 50 directly executes the process of (P-5).

[0049] Next, the calculation unit 50 repeatedly executes the following process (PL-1): copying the reference average value N_AVE{PART_NUM} of the current image to the reference average value B_AVE{PART_NUM} of the image immediately preceding it; and calculating, using the reference value buffer Y, the average value of the reference values ​​of all pixels within each grid of the frame image in the subject's eye image stored in the current image buffer N (divided areas in the subject's eye image), and storing the calculated value as the reference average value N_AVE{PART_NUM} of each grid in the current image (subject's eye image). After storing the reference average values ​​N_AVE{PART_NUM} for all grids in the storage means 20, the calculation unit 50 ends the imaging and digitization process P (image capturing and digitization process end).

[0050] 6 to 9, the specific processing contents of the high dynamic range processing H will be described. The calculation unit 50 executes a process (H-1) in which it sets changeCnt, a variable used to count the number of times that a grid {i} (i is the grid serial number) of a frame image in the current image buffer N and a grid {i} of the output image buffer OUT at the same position are dissimilar (the number of dissimilar grids in the frame image), to 0 and stores this in the storage means 20, and also reads the output image buffer OUT from the storage means 20 and copies the intermediate processing buffer M to the output image buffer OUT. Next, the calculation unit 50 executes a process (H-2) in which it calculates the absolute value DIFF of the difference between the reference average value N_AVE{i} for each grid in the current image buffer N and the reference average value B_AVE{i} for each grid in the previous image buffer B.

[0051] Next, the calculation unit 50 compares whether the calculated DIFF exceeds the first change amount threshold THR (H-3), and if the calculated DIFF exceeds the first change amount threshold THR (Yes), executes a process (H-4) of adding 1 to changeCnt. On the other hand, if the calculated DIFF does not exceed the first change amount threshold THR (No), the calculation unit 50 as a high dynamic range image generating means executes a process (H-5) of superimposing the grid {i} of the current image buffer N and the grid {i} of the output image buffer OUT (both grids at the same position (same serial number); divided areas at the same position in the subject's eyeball image) and reflecting the HDR processed data (hatched portion in FIG. 7) that has been subjected to high dynamic range image generation processing using a known method in the intermediate processing buffer M. The calculation unit 50 executes a process (HL-1) of repeating the processes (H-2) to (H-5) for all grids.

[0052] After executing the process (HL-1) for all grids, the calculation unit 50 executes a process (H-6) to check whether changeCnt exceeds the area change threshold AREA_THR (corresponding to the second threshold in the claims). The area change threshold AREA_THR is preferably a value equal to or greater than half the number of grids (the final number in the grid serial numbering). If changeCnt exceeds the area change threshold AREA_THR (Yes), the calculation unit 50 proceeds to the blink determination process subroutine (MS) and then terminates the high dynamic range conversion process H (end of high dynamic range conversion process). On the other hand, if changeCnt does not exceed the area change threshold AREA_THR (No), the calculation unit 50 executes a process (H-7) to copy the intermediate processing buffer M to the output image buffer OUT, and then terminates the high dynamic range conversion process H (end of high dynamic range conversion process).

[0053] FIG. 8 is a flow diagram of a subroutine of the blink determination process. FIG. 9 is an explanatory diagram showing a specific example of the blink determination process. Here, as shown in FIG. 9, the blink determination process MS will be described in the case where the number of times that the current image (current frame image) has been determined to have changed compared to the immediately previous frame image under the same shooting conditions (same exposure conditions) is four. When the blink determination process MS starts, the calculation unit 50 executes a process (MS-1) of adding 1 to the value of ChN, which is a variable that counts the number of image changes (ChN=0 at the start of the blink determination process MS). Next, the calculation unit 50 executes a process (MS-2) of checking whether the value of ChN is 1 or not.

[0054] When the value of ChN, which indicates the first change in the photographed image of the subject's eye, is 1 (Yes in MS-2), the calculation unit 50 executes a process (MS-3) in which the photographed image data of the subject's eye one frame before the current image at that time and the data of the photographed time of that photographed image data of the subject's eye are stored as the reference image buffer JB and the reference image time data JBT, respectively, in the storage means 20. The reference image buffer JB is set as a reference value in each grid in the frame image (a value calculated based on the RGB values ​​of each pixel in the grid, and here calculated in the same way as Y in FIG. 5).

[0055] Next, the calculation unit 50 executes a process (MS-4) in which the data of the photographed image of the subject's eye when the photographed image of the subject's eye changes for the first time and the data of the photographed time of the image data are stored in the storage means 20 as the first changed image data JP1 and the first changed image time data JPT1, respectively. On the other hand, if the value of ChN is not 1 (No in MS-2), the calculation unit 50 omits the process (MS-3) in which the reference image buffer JB and the reference image time data JBT are stored in the storage means 20, and stores the data of the photographed image of the subject's eye when the ChNth change is made and the data of the photographed time of the image data, respectively, as the first changed image data JP1 and the first changed image time data JPT1. ChN and ChN change image time data JPT ChN The process (MS-4) is executed to store the ChN-th changed image data JP ChN The calculation method can be the same as the calculation method for the reference image buffer JB.

[0056] Next, the calculation unit 50 calculates the ChN-th changed image data JP ChN and the reference image buffer JB, the total difference value DIFF2 of the reference values ​​of the same grid number is calculated (MS-5). ChN The calculation unit 50 then calculates the difference between the ChN-th change image data JP and the reference value for each of the same grid points in the reference image buffer JB.ChN and the reference image buffer JB, the total difference value DIFF2 of the reference values ​​of the same grid number is larger (MS-6).

[0057] If the total difference value DIFF2 of the reference values ​​is greater than the second change amount threshold THR2 (Yes in MS-6), the blink determination process MS is terminated (end of blink determination process). On the other hand, if the total difference value DIFF2 of the reference values ​​is not greater than the second change amount threshold THR2 (No in MS-6), the calculation unit 50 calculates the ChN-th change image time data JPT ChN and the reference image time data JBT is shorter than a blink determination reference time T (corresponding to the first threshold in the claims) stored in advance in the storage means 20 (process MS-7).

[0058] ChN change image time data JPT ChN If the difference between the ChN-th changed image time data JPT and the reference image time data JBT is shorter than the blink judgment reference time T stored in advance in the storage means 20 (Yes in MS-7), the calculation unit 50 ends the blink judgment process MS (end of blink judgment process). ChN If the difference between the reference image time data JBT and the reference image time data JBT is longer than the blink judgment reference time T pre-stored in the storage means 20 (No in MS-7), the calculation unit 50 executes a process (MS-8) to set the restart flag to TRUE, and then terminates the blink judgment process MS (end of blink judgment process).

[0059] The above processing will be described in more detail with reference to FIG. 9. When it is first determined that the current frame image of the subject's eye has changed from the previous frame image of the subject's eye, the data of the current frame image of the subject's eye becomes the first changed image data JP1, and the current image time data becomes the first changed image time data JPT1. Furthermore, the data of the previous frame of the subject's eye becomes the reference image buffer JB, and the capture time of the previous frame of the subject's eye becomes the reference image time data JBT. If the total difference value DIFF2 between the reference values ​​for each grid point in the reference image buffer JB and the first changed image data JP1 exceeds the second change amount threshold THR2, the calculation unit 50 performs no processing and the blink determination processing MS ends. In the case of the pattern shown in FIG. 9, the total difference value DIFF2 between the reference values ​​for each grid point in all of the first changed image data JP1 through the third changed image data JP3 exceeds the second change amount threshold THR2, and therefore the calculation unit 50 performs no processing and the blink determination processing MS ends.

[0060] For the fourth varied image data JP4, the total difference value DIFF2 between the reference values ​​for each grid point in the reference image buffer JB and the fourth varied image data JP4 does not exceed the second change amount threshold THR2, so the calculation unit 50 determines that the fourth varied image data JP4 is the same image as the reference image buffer JB. In this case, the calculation unit 50 calculates the amount of time change from the reference image buffer JB to the fourth varied image data JP4, which is the same image as the reference image buffer JB, as the difference between the fourth varied image time data JPT4 and the reference image time data JBT, and if the calculated amount of time change is within the blink determination reference time T, the blink determination process MS ends without performing any other processing. On the other hand, if the calculated amount of change over time exceeds the range of the blink judgment reference time T, the calculation unit 50 determines that the time from when the image of the subject's eye changes from the reference image buffer JB to when it returns to the same image of the subject's eye as the reference image buffer JB (here, the fourth change image data JP4) exceeds the blink judgment reference time T, and therefore, in order to discard the data up to that point, the calculation unit 50 executes a process (MS-8) to set the shooting restart flag to TRUE, and then terminates the blink judgment process MS.

[0061] When the subroutine of the blink determination process MS inserted in the high dynamic range process H is completed, the high dynamic range process H also ends (end of the high dynamic range process).

[0062] By including the blink determination process MS in the process of generating a high dynamic range image in this way, even if images captured under the same shooting conditions (same exposure conditions) include images of blinking, as long as only the images of the subject's eyeballs captured at the time of blinking are used in the process of generating the high dynamic range image, no distortion will occur in the high dynamic range image. Furthermore, because the images of the subject's eyeballs captured before blinking can be used in the process of generating the high dynamic range image, the amount of data discarded from the images of the subject's eyeballs can be minimized, making it possible to generate the high dynamic range image in a short time.

[0063] On the other hand, if the time it takes from when the image data changes from the reference image buffer JB until it returns to the same photographed image of the subject's eye as in the reference image buffer JB exceeds the blink determination reference time T, then although the photographed image of the subject's eye has numerically returned to the reference image data, it is highly likely that this is not a blink, and there is a possibility that a change has occurred in the subject's line of sight in the photographed image of the subject's eye. If the photographed image data of the subject's eye after a change in line of sight is combined with the photographed image of the subject's eye before the line of sight change to generate a high dynamic range image, there is a risk of distortion in the high dynamic range image. Therefore, it is preferable not to use such photographed image data of the subject's eye, but to use re-photographed photographed image data of the subject's eye to generate a high dynamic range image.

[0064] Next, the calculation unit 50 executes the output screen update / photography condition setting process O shown in Fig. 10. When the output screen update / photography condition setting process O starts, the calculation unit 50, which serves as image display control means, executes a process (O-1) to output data stored in the output image buffer OUT to a display unit such as a display. Next, the calculation unit 50 executes a process (O-2) to determine whether or not the photography restart flag is TRUE. If the photography restart flag is TRUE (Yes in O-2), the calculation unit 50 executes a process (O-3) to maintain the photography conditions in the photography means 10 at the current photography conditions, and then executes a process (O-4) to clear ChN, which is a variable for the number of image changes, and ends the output screen update / photography condition setting process O (end of output screen update / photography condition setting process). On the other hand, if the shooting restart flag is not TRUE (No at O-2), the calculation unit 50 executes a process (O-5) to set the shooting means 10 to the next shooting conditions, and then executes a process (O-4) to clear ChN, which is a variable for the number of image changes, and ends the output screen update / shooting condition setting process O (end of output screen update / shooting condition setting process).

[0065] 11, a plurality of photographing conditions are set for the photographing means 10 in this embodiment based on exposure time. Specifically, a photographing condition in which the exposure time is a reference exposure time RT is set as the reference photographing condition, and modified exposure time 1 (RT-Δt) is set by shortening the exposure time by a predetermined time Δt from the reference exposure time RT, modified exposure time 2 (RT+Δt) is set by lengthening the exposure time by the predetermined time Δt from the reference exposure time RT, modified exposure time 3 (RT-2Δt) is set by shortening the exposure time by twice the predetermined time Δt from the reference exposure time RT, modified exposure time 4 (RT+2Δt) is set by lengthening the exposure time by twice the predetermined time Δt from the reference exposure time RT, modified exposure time 5 (RT-3Δt) is set by shortening the exposure time by three times the predetermined time Δt from the reference exposure time RT, and modified exposure time 6 (RT+3Δt) is set by lengthening the exposure time by three times the predetermined time Δt from the reference exposure time RT. In this way, the photographing conditions of the photographing means 10 in this embodiment are set to a change width that is an integral multiple of a predetermined time Δt set in advance with respect to the reference exposure time RT, but this is not limited to this. Also, changes in the photographing conditions can be set based on factors other than the exposure time.

[0066] As described above, according to the present invention, when it is determined that the image data photographed by the subject's eye differs from the reference image during the process of converting the image data photographed by the subject's eye into a high dynamic range image, the high dynamic range conversion process H is not performed on the frame images during which the image data photographed by the subject's eye differs from the reference image, and if the elapsed time until the image data photographed by the subject's eye returns to the reference image data is within a predetermined time, the high dynamic range conversion process H is resumed from the point at which the image data photographed by the subject's eye returns to the reference image, thereby advantageously avoiding distortion of the image after the high dynamic range conversion process. By employing such high dynamic range conversion process H, it is possible to reduce the amount of discarded image data of the subject's eye (discarding of image data photographed by the subject's eye that is not used in the high dynamic range conversion process H), which is also advantageous in that it becomes possible to efficiently perform the high dynamic range conversion process H.

[0067] Furthermore, in the above embodiment, the storage means 20, the image display unit 30, and the calculation unit 50 are integrated with the ophthalmologic apparatus 100, but the present invention is not limited to this. At least one of the storage means 20, the image display unit 30, and the calculation unit 50 may be connected via an external input / output unit 40. An example of the calculation unit 50 connected via the external input / output unit 40 is a personal computer on which the high dynamic range image generation program according to the present invention is installed in an executable manner.

[0068] Although the ophthalmologic apparatus 100 according to the present embodiment has been described above, the present invention is not limited to the above embodiment. For example, in the above embodiment, when setting a reference image, the examiner may select photographed image data of the subject's eyeball from photographed image data of the subject's eyeball and set the selected photographed image as the reference image. Alternatively, a reference image for selecting a reference image may be stored in advance in the storage unit 20, the calculation unit 50 may display the reference image for selecting a reference image on the image display unit 30, and the examiner may select the reference image by determining the similarity between the photographed image data of the subject's eyeball and the reference image for selecting a reference image. Alternatively, the calculation unit 50 may perform a similarity determination process between images using a known method or the image similarity determination means described above, compare the similarity between the reference image for selecting a reference image and the photographed image, and set the photographed image with the highest similarity as the reference image.

[0069] Furthermore, in the above embodiment, the ophthalmic apparatus 100 having the calculation unit 50 functioning as a high dynamic range image generating means and the high dynamic range image generating method have been described, but the present invention is not limited to the above embodiment. There is also an invention as a high dynamic range image generating program that can cause the calculation unit 50 of the ophthalmic apparatus 100 to execute the high dynamic range image generating method described in the above embodiment.

[0070] Furthermore, although the photographed images of the subject's eyeballs in the above embodiments are exemplified as moving images of 30 to 60 frames per second, the present invention is not limited to this. Moving images of more than 60 frames per second may also be used, and photographed images of the subject's eyeballs that pair multiple still images with the photographing time data of each still image may also be used.

[0071] Furthermore, in the above embodiment, an example is shown in which the calculation unit 50 as image display control means performs processing to display both the reference image and the high dynamic range image stored in the output image buffer OUT on the image display unit 30, but the present invention is not limited to this. The calculation unit 50 may simply cause the image display unit 30 to display at least one of the reference image and the high dynamic range image stored in the output image buffer OUT. In this case, the reference image may be displayed on the image display unit 30 until the processing to generate the high dynamic range image is completed, and after the processing to generate the high dynamic range image is completed, the image display unit 30 may display the high dynamic range image stored in the output image buffer OUT.

[0072] Furthermore, it is also possible to adopt a form in which the above-described embodiments and modifications are appropriately combined. [Explanation of symbols]

[0073] 10: Shooting method 20: Memory means 30: Image display unit 40: External input / output section 50: Calculation unit (output image initialization means, image similarity / difference determination means, high dynamic range image generation means) 100: Ophthalmology equipment

Claims

1. an imaging means for capturing images of the subject's eyeball under different exposure conditions at regular time intervals; a storage means for storing the subject's eyeball image together with photographing time information as photographing data, and for storing the subject's eyeball image selected from the subject's eyeball image in the photographing data based on a similarity with a reference image for selecting a reference image or by an examiner as a reference image; an output image initialization means for storing a copy of the reference image in the storage means as an output image; a high dynamic range image generating means for performing high dynamic range processing on the output image to generate a high dynamic range image; and an image similarity determining means for determining whether the subject's eyeball image in the photographing data is the same as the reference image, The high dynamic range image generating means is an ophthalmic device characterized in that the image similarity determination means compares the similarity between the subject's eye image and the reference image in order of oldest to newest shooting time information, and only if it determines that the subject's eye image and the reference image are the same, performs a process of overlaying the subject's eye image on the output image, updating the output image, and storing it in the storage means, on the subject's eye image under the same exposure conditions, thereby generating the high dynamic range image.

2. The high dynamic range image generating means executes a process of allowing the output image to continue to be used when a difference between the photographing time information when the image similarity determination means first determines that the subject's eyeball image is different from the reference image and the photographing time information when the image similarity determination means determines that the subject's eyeball image has returned to the reference image is within a first threshold value set in advance; a process for causing the photographing means to photograph the subject's eyeball image again, when a difference between the photographing time information when the image similarity determination means first determined that the subject's eyeball image is different from the reference image and the photographing time information when the image similarity determination means determined that the subject's eyeball image has returned to the reference image exceeds the first threshold value that is set in advance, the process for causing the photographing means to photograph the subject's eyeball image again, a process for storing the subject's eyeball image photographed again together with the photographing time information in the storage means as the photographing data, a process for storing a subject's eyeball image selected from the subject's eyeball images in the photographing data in the storage means as the reference image, and a process for causing the output image initialization means to store a copy of the reference image in the storage means as the output image.

2. The ophthalmologic apparatus according to claim 1, wherein the above steps are executed.

3. The image similarity / differentity determination means a process of dividing the reference image, the subject's eyeball image, and the output image into a plurality of divided regions each having the same shape and the same layout; updating the output image by superimposing the divided area in the subject's eye image on the divided area in the output image when a difference between the numerical values ​​for determining similarity between the divided areas in the subject's eye image and the reference image that are at the same position is equal to or less than a second threshold value that is set in advance; 3. The ophthalmologic apparatus according to claim 1, wherein, in each of the divided regions of the subject's eyeball image and the reference image that are in the same position, if the difference in the numerical value for determining similarity between the divided regions exceeds the second threshold value, a process of maintaining the output image is executed.

4. The ophthalmologic apparatus according to claim 3, wherein the numerical value for determining similarity or difference is an average value of the values ​​or converted values ​​of each pixel in each divided area, based on at least one of the RGB values ​​(R value, G value, B value) of each pixel of the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

5. an image display unit that displays at least one of the reference image and the output image; an image display control unit that displays at least one of the reference image and the output image on the image display unit; 3. The ophthalmologic apparatus according to claim 1, wherein the image display control means causes the image display unit to display the output image every time the output image is updated.

6. an image display unit that displays at least one of the reference image and the output image; an image display control unit that displays at least one of the reference image and the output image on the image display unit; 4. The ophthalmologic apparatus according to claim 3, wherein the image display control means causes the image display unit to display the output image every time the output image is updated.

7. an image display unit that displays at least one of the reference image and the output image; an image display control unit that displays at least one of the reference image and the output image on the image display unit; 5. The ophthalmologic apparatus according to claim 4, wherein the image display control means causes the image display unit to display the output image every time the output image is updated.

8. A high dynamic range image generating method for an ophthalmic apparatus, which is used in an ophthalmic apparatus including an imaging means for capturing an image of an eyeball of a subject, a storage means, and a calculation unit, comprising: a step in which the calculation unit causes the photographing means to photograph images of the subject's eyeball under different exposure conditions at regular time intervals; a step of causing the calculation unit to store the subject's eyeball image together with photographing time information in the storage means as photographing data; a step of causing the calculation unit to select, from the subject's eyeball images in the photographing data, an eyeball image of the subject selected based on a similarity with a reference image for selecting a reference image or selected by an examiner, and storing the selected eyeball image in the storage means as a reference image; a step of causing the computing unit to store a copy of the reference image as an output image in the storage means; a step in which the calculation unit performs high dynamic range processing on the output image to generate a high dynamic range image; the calculation unit determines whether the image of the subject's eyeball in the imaging data is the same as the reference image, The step of generating the high dynamic range image includes the steps of: causing the calculation unit to compare the similarity between the subject's eye image and the reference image in chronological order of the shooting time information; and, only when it is determined that the subject's eye image and the reference image are the same, causing the calculation unit to overlay the subject's eye image on the output image, update the output image, and store the output image in the storage means; and, when it is determined that the subject's eye image is different from the reference image, causing the calculation unit to maintain the output image. A method for generating a high dynamic range image for an ophthalmic device, characterized in that:

9. a step of allowing the output image to continue to be used when a difference between the photographing time information when the calculation unit first determines that the subject's eyeball image is different from the reference image and the photographing time information when the calculation unit determines that the subject's eyeball image has returned to the reference image is within a first threshold value set in advance; when the difference between the photographing time information when the calculation unit first determines that the subject's eyeball image is different from the reference image and the photographing time information when the calculation unit determines that the subject's eyeball image has returned to the reference image exceeds the first threshold value set in advance, the calculation unit performs the steps of causing the photographing means to photograph the subject's eyeball image again, storing the re-photographed subject's eyeball image together with the photographing time information in the storage means as the photographing data, storing a subject's eyeball image selected from the subject's eyeball images in the photographing data in the storage means as the reference image, and causing the calculation unit to store a copy of the reference image in the storage means as the output image, 9. The method for generating a high dynamic range image for an ophthalmic device according to claim 8, wherein each of the steps comprises:

10. a step in which the calculation unit divides the reference image, the subject's eyeball image, and the output image into a plurality of divided regions each having the same shape and the same arrangement; updating the output image by superimposing the divided area in the subject's eyeball image on the divided area in the output image when the calculation unit determines that the difference between the numerical values ​​for similarity determination between the divided areas in the subject's eyeball image and the reference image, which are at the same position, is equal to or less than a second threshold value that is set in advance; and a step of maintaining the output image when the calculation unit determines that the difference in the numerical value for determining similarity between each of the divided areas of the subject's eyeball image and the reference image, which are located at the same position, exceeds the second threshold value.

11. The high dynamic range image generating method for an ophthalmic device according to claim 10, characterized in that the calculation unit uses the average value of the values ​​or converted values ​​of each pixel in each divided area as the numerical value for determining similarity or difference, based on either at least one value (R value, G value, B value) of the RGB values ​​of each pixel of the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

12. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 10. The method for generating a high dynamic range image for an ophthalmic device according to claim 8, further comprising a step in which the calculation unit displays the output image on the image display unit each time the output image is updated.

13. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 11. The method for generating a high dynamic range image for an ophthalmic device according to claim 10, further comprising a step in which the calculation unit displays the output image on the image display unit each time the output image is updated.

14. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 12. The method for generating a high dynamic range image for an ophthalmic device according to claim 11, further comprising a step in which the calculation unit displays the output image on the image display unit each time the output image is updated.

15. A high dynamic range image generating program for an ophthalmic apparatus, which is used in an ophthalmic apparatus including an imaging means for capturing an image of an eyeball of a subject, a storage means, and a calculation unit, comprising: A process of causing the photographing means to photograph images of the subject's eyeball under different exposure conditions at regular time intervals; a process of storing the subject's eyeball image together with photographing time information in the storage means as photographing data; a process of selecting an eye image of the subject from the eye images of the subject in the photographing data based on a similarity with a reference image for selecting a reference image or selecting an eye image by an examiner, and storing the selected eye image in the storage means as a reference image; storing a copy of the reference image in the storage means as an output image; A process of performing a high dynamic range process on the output image to generate a high dynamic range image; and determining whether the image of the subject's eyeball in the photographed data is the same as the reference image. The high dynamic range image generating process includes: a process of comparing the similarity between the subject's eyeball image and the reference image in order of oldest photographing time information, and when it is determined that the subject's eyeball image and the reference image are the same, overlaying the subject's eyeball image on the output image to update the output image and store the updated image in the storage means; a process for comparing the similarity between the subject's eye image and the reference image in order of oldest photographing time information, and maintaining the output image if it is determined that the subject's eye image is different from the reference image.

16. a process of continuing to use the output image when a difference between the photographing time information when it is first determined that the subject's eye image is different from the reference image and the photographing time information when it is determined that the subject's eye image has returned to the reference image is within a first threshold value set in advance; a process for causing the photographing means to photograph the subject's eyeball image again, when a difference between the photographing time information when it was first determined that the subject's eyeball image was different from the reference image and the photographing time information when it was determined that the subject's eyeball image had returned to the reference image exceeds a first threshold value that is set in advance; a process for storing the subject's eyeball image photographed again together with the photographing time information in the storage means as the photographing data; a process for storing a subject's eyeball image selected from the subject's eyeball images in the photographing data in the storage means as the reference image; and a process for storing a copy of the reference image in the storage means as the output image.

16. The high dynamic range image generating program for an ophthalmologic apparatus according to claim 15, wherein the program causes the calculation unit to execute the above steps.

17. a process of dividing the reference image, the subject's eyeball image, and the output image into a plurality of divided regions each having the same shape and the same layout; a process of updating the output image by superimposing the divided area in the subject's eyeball image on the divided area in the output image when it is determined that the difference in the numerical value for determining similarity between the divided areas in the subject's eyeball image and the reference image, which are at the same position as each other, is equal to or less than a second threshold value that is set in advance; maintaining the output image when it is determined that the difference between the numerical values ​​for similarity determination between the divided regions of the subject's eyeball image and the reference image, which are at the same position as each other, exceeds the second threshold value; 17. The high dynamic range image generating program for an ophthalmologic apparatus according to claim 15, wherein the program causes the calculation unit to execute the above steps.

18. The high dynamic range image generation program for an ophthalmic device described in claim 17, characterized in that the calculation unit uses the average value of the values ​​or converted values ​​of each pixel in each of the divided areas as the numerical value for determining similarity or difference, based on at least one value (R value, G value, B value) of the RGB values ​​of each pixel of the subject's eyeball image and the reference image, or a converted value obtained by converting the RGB values ​​using a predetermined conversion formula.

19. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 17. The high dynamic range image generating program for an ophthalmic apparatus according to claim 15, wherein the calculation unit is caused to display the output image on the image display unit every time the output image is updated.

20. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 18. The high dynamic range image generating program for an ophthalmologic apparatus according to claim 17, wherein the calculation unit is caused to display the output image on the image display unit every time the output image is updated.

21. the ophthalmologic apparatus further includes an image display unit that displays at least one of the reference image and the output image, and an image display control unit that causes at least one of the reference image and the output image to be displayed on the image display unit, 19. The high dynamic range image generating program for an ophthalmologic apparatus according to claim 18, wherein the calculation unit is caused to display the output image on the image display unit every time the output image is updated.

Images