JPH09308609A - Ophthalmologic image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively store a fluorescent contrast image without omitting any required information part. SOLUTION: An ICG is injected to a reagent and at the same time, a timer 28 is started. A photographer observes the output image or the like of an infrared observation enable CCD camera 22 connected to the finder part of an eyebottom camera 21 and when fluorescent light appears on the eyebottom of an eye to be examined, a photograph switch is pushed. Timer data at the time of photographing are measured by the timer 28 and stored in a data processing part 24 every time. The photographed images are photoelectrically transduced on the CCD camera 22, afterwards, converted to digital data by an A/D converter 23 and stored in the data processing part 24. In case of ICG fluorescent contrast photographing, the time of a change from initial image to following image is previously set to a timer data setting part 29 and after photographing time exceeds set time, prescribed picture quality improving processing is executed to the images transferred from the data processing part 24 to a picture quality improving part 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ophthalmic image processing apparatus for performing image processing of a fundus image or the like obtained by an ophthalmologic apparatus.

[0002]

2. Description of the Related Art Conventionally, fluorescence contrast imaging, which has been performed to examine the blood flow condition of the fundus of the eye, has been performed by recording on a 35 mm film using a fundus camera, but recently, a fundus camera. A method is generally known in which an image captured by a CCD camera connected to is digitally converted and the image data is recorded.

FIG. 15 is a block diagram of the first conventional example, in which the output of the CCD camera 2 connected to the fundus camera 1 is A / D.
The output of the A / D converter 3 and the output of the timer 4 are connected to a converter 3, and are connected to a data processing unit 5 for temporarily storing image data and managing timer data.
Is connected to the hard disk 7 via a digital interface 6 such as SCSI.

In the above-described structure, first, a contrast agent such as fluorescein or ICG (indocyanine green) is intravenously injected into a subject prior to photographing, and at the same time, the timer 4 is started by a start switch (not shown). Then, the photographer starts photographing when fluorescence appears on the fundus of the eye to be examined, and timer data at the time of photographing is stored in the data processing unit 5 each time. The photographed image is photoelectrically converted by the CCD camera 2, converted into digital data by the A / D converter 3 and stored in the data processing unit 5, and further, via the digital interface 6, the hard disk 7 together with the timer data. Stored in.

The images obtained by such fluorescence contrast imaging are usually roughly divided into an initial image from the appearance of fluorescence up to several minutes and a later image after several tens of minutes, and each is used for diagnosis. The features of the two contrast-enhanced fluorescence images are greatly different between the images, and the details and brightness of the blood vessels are clear in the initial image, and the changes with time are significant, whereas the latter image is blurred overall and the contrast is not clear. , The change over time is gradual.

Therefore, various attempts have been proposed to improve the image quality of the later image, and generally, histogram stretching processing, contrast enhancement processing using a look-up table, and the like are performed.

FIG. 16 shows a configuration diagram of a second conventional example, and the same reference numerals as those in FIG. 15 represent the same members. The output of the CCD camera 2 is sequentially connected to the A / D converter 3, the memory 8 for temporarily storing image data, the D / A converter 9, and the television monitor 10, and the output of the timer 4 is the character generator. It is connected to the D / A converter 9 via 11.

In the above-mentioned structure, when photographing is started in the same manner as the first conventional example, the timer data at the time of photographing is sent to the D / A converter 9 as character data each time by the character generator 11. The captured image is stored in the memory 16 as digital data and is displayed on the television monitor 10 together with the timer data via the D / A converter 9.

In particular, as described in the first conventional example, the late fluorescence contrast image becomes a blurred image with no clear contrast, and the condition of the retina and the condition of the fundus such as hemorrhagic spots, white spots, and photocoagulation spots are accurate. Since it cannot be grasped, it is displayed on the television monitor 10 by superimposing the fundus image captured through the infrared transmission filter on the late fluorescence contrast image, and the positional relationship between them is confirmed.

FIG. 17 shows a block diagram of a third conventional example provided with image quality improving means for improving the image quality of a later image obtained by fluorescence contrast imaging. The output of the CCD camera 2 is the character synthesizing section 12 and the image quality improving. The means 13, the video tape recorder 14, and the television monitor 10 are sequentially connected, and the output of the timer 4 is connected to the character synthesizing section 12 via the character generator 11.

In this structure, the fluorescent switch is intravenously injected into the subject to start the start switch, and then the recording switch of the video tape recorder 14 is pressed. The fluorescence contrast image photoelectrically converted by the CCD camera 2 is combined by the character combining unit 12 with the character indicating the timer value generated by the character generator 11 after being counted by the timer 4. Then, after the contrast and the like are improved by the image quality improving unit 13, the video is recorded on the video tape recorder 14, and the recorded moving image is displayed on the television monitor 10.

For the fluorescence contrast image improved by the image quality improving unit 13, a changeover switch (not shown) is connected to the image quality improving unit 13, and the changeover switch is operated to improve the image quality only for the fluorescent late image. You may comprise.

FIG. 18 is a block diagram of the fourth conventional example, in which the output of the CCD camera 2 connected to the fundus camera 1 is A /
The D converter 3, the image memory 8 including a volatile memory such as a RAM, the D / A converter 9, and the television monitor 10 are sequentially connected, and further connected to the hard disk via the interface 6. Further, the output of the timer 15 built in the fundus camera 1 is connected to a timer data storage unit 16 that stores timer data for each photographing, and further, D /
It is connected to the television monitor 10 via the A converter 9 and to the hard disk 7 via the interface 6.

In the above-mentioned structure, first, before photographing, I
The CG is intravenously injected to the subject, and at the same time as the intravenous injection, the start switch (not shown) of the fundus camera 1 is operated to start the timer 15. The photographer starts photographing when fluorescence appears on the fundus of the subject, and the timer data of the timer 4 is stored in the timer data storage unit 16 each time the photographing is performed.

The photographed image is photoelectrically converted by the CCD camera 1, converted into digital data by the A / D converter 3, and stored in the image memory 8. Further, this image can be confirmed on the television monitor 10 via the D / A converter 9, and together with the timer data stored in the timer data storage unit 16, the hard disk 7 via the digital interface 6. Stored in.

[0016]

However, the above-mentioned prior art has the following problems. (B) High resolution is required for the initial image of fluorescence contrast imaging because it contains a lot of necessary information in the high frequency component, and high resolution is not required for the latter image because it contains a lot of information in the low frequency component. There is a characteristic that. However, since recording is performed based on the same method for both the initial image and the latter image, unnecessary data is also recorded as a result.

(B) Since the degree of image quality improvement is uniform, the image quality improvement effect cannot be fully utilized for the fluorescence contrast image which changes every moment when recording an image.

(C) When improving the image quality of the fluorescent late image, it is necessary to determine that the image has reached the latter period and perform an operation for improving the image quality.

(D) The operation is complicated because it is visually judged whether or not the image is a late image of fluorescence, and the infrared light image and the like are synthesized and displayed each time.

(E) Since the ratio of superimposition at the time of superimposing display is uniform, the fluorescent contrast images that change from moment to moment are displayed without sufficiently exerting the superimposing effect. .

The first object of the present invention is the above-mentioned problem (a).
SUMMARY OF THE INVENTION It is an object of the present invention to provide an ophthalmic image processing device capable of effectively storing information without missing information components necessary for a fluorescence contrast image.

The second object of the present invention is the above-mentioned problem (b).
It is an object of the present invention to provide an ophthalmic image processing device capable of solving the above problem and improving the image quality suitable for the fluorescence contrast image at each time.

The third object of the present invention is the above-mentioned problem (c).
It is an object of the present invention to provide an ophthalmic image processing apparatus capable of automatically improving the image quality only from the late fluorescent image.

A fourth object of the present invention is the above-mentioned problem (d).
It is an object of the present invention to provide an ophthalmic image processing device capable of automatically confirming the condition of the fundus of the eye even in the later fluorescence image.

The fifth object of the present invention is the above-mentioned problem (e).
SUMMARY OF THE INVENTION It is an object of the present invention to provide an ophthalmic image processing device capable of solving the above-mentioned problem and superimposing a display suitable for a fluorescent contrast image for each time and changing the display.

[0026]

An ophthalmic image processing apparatus according to a first aspect of the present invention for achieving the above object is an image inputting means for inputting a fluorescent fundus image, and a time when an image is input to the image inputting means. Is provided, and an image processing unit for performing a predetermined process on the image input by the image input unit in association with the timer data measured by the timer.

Further, the ophthalmic image processing apparatus according to the second aspect of the present invention sets the image input means for inputting the fluorescent fundus image, the timer for counting the time when the image is input to the image input means, and the threshold value for the timer. A timer threshold setting means for performing the predetermined processing, and an image processing means for performing a predetermined process on the image input from the image input means based on the threshold set by the timer threshold setting means.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail with reference to the embodiments shown in FIGS. FIG. 1 shows a block diagram of the first embodiment. The output of a CCD camera 22 connected to a fundus camera 21 is an A / D converter 23, a data processing unit for temporarily storing image data and managing timer data. 24,
The image quality improving unit 25, a digital interface 26 such as SCSI, and a hard disk 27 are sequentially connected. On the other hand, the output of the timer 28 is connected to the data processing unit 24, the timer data setting unit 29, and the image quality improvement parameter setting unit 30, and the outputs of the timer data setting unit 29 and the image quality improvement parameter setting unit 30 are sent to the image quality improvement unit 25. The output of the image quality improvement parameter setting unit 30 is connected to the hard disk 27 via the interface 26.

In the above structure, first, the ICG is applied to the subject.
, And simultaneously press the timer start switch (not shown) to start the timer 28. The photographer observes an output image or the like of the CCD camera 22 which is connected to a finder section (not shown) of the fundus camera 21 and is capable of infrared observation, and when fluorescence appears on the fundus of the eye to be examined, presses a photographing switch (not shown) on the fundus camera 21. Push.

The timer data at the time of photographing is measured by the timer 28 and stored in the data processing unit 24 each time. The photographed image is photoelectrically converted by the CCD camera 22 connected to the fundus camera 21, further converted into digital data by the A / D converter 23, and stored in the data processing unit 24. The stored image may be confirmed on a television monitor (not shown) via a D / A converter (not shown).

In the ICG fluorescence contrast imaging, the time for changing from the initial image to the latter image in advance is set by the timer data setting unit 29.
When the shooting time exceeds the set time, a predetermined image quality improving process is performed on the image transferred from the data processing unit 24 to the image quality improving unit 25 thereafter. Here, the setting of data in the timer data setting unit 29 may be programmed in advance, or may be configured by using a data input means such as a keyboard or a mouse (not shown).

Further, the image quality improving process in the image quality improving unit 25 starts when the time set in the timer data setting unit 29 has elapsed, but by a process execution switch (not shown) connected to the image quality improving unit 25. It can also be configured to switch. Then, the image on the data processing unit 24 is stored in the hard disk 27 via the digital interface 26 together with the timer data.

The image quality improving process in the image quality improving unit 25 is performed as follows. (1) Contrast enhancement by LUT (look-up table) FIGS. 2 and 3 are graph diagrams of the LUT used for image quality improvement processing, where the horizontal axis is the input image level, for example, a commonly used 8-bit density gradation. In the case of the image data having, the gradation is represented by 0 to 255. On the other hand, the vertical axis represents the output image level after processing, and this graph is used to determine which density gradation in the output image each density gradation of the input image corresponds to.

FIG. 2 shows the timer data setting section 2 from the beginning of contrast enhancement.
9 shows the LUT immediately after the late contrast period used immediately after the lapse of the time set in FIG. 9, and FIG. 3 shows the LUT immediately after the end of the late contrast period, which is used immediately before the end of the fluorescence contrast imaging. The LUT is indicated by.

In this embodiment, the shape of the LUT shown in FIG. 2 to the shape of the LUT shown in FIG. 3 is linearly changed based on the value measured by the timer 28, so that the specific shape of the LUT is obtained. It is uniquely determined according to the value measured by the timer 28.

The image quality improvement parameter setting section 30 shows the correspondence between the value measured by the timer 28 and the value of the LUT used at that time in a table format. For example, the value measured by the timer 28 is 10 times. The LUT used in the case of 15 minutes is stored in the table format of the output image level with respect to the input image level.

At this time, the time of the timer 28 using the LUT of FIG. 2 and the time of the timer 28 using the LUT of FIG. 3 are stored in advance or are connected to the image quality improvement parameter setting unit 30. It is set by input means such as a mouse and a keyboard (not shown). Further, although the image quality improvement parameter setting unit 30 uses the LUT as a table format, it may have a format in which a function with time as a variable is used.

(2) Contrast Enhancement by Stretching Histogram FIGS. 4 and 5 are graphs of the density histogram of an image, where the horizontal axis is the density level, and 0 to 255 in the image data of 8-bit density gradation. It is represented by gradation, and the vertical axis represents the number of pixels for each density level.

FIG. 4 shows the timer data setting unit 2 from the initial stage of contrast enhancement.
FIG. 5 shows the histogram stretching state immediately after the late contrast period after the time set in 9 is reached, and FIG. 5 shows a histogram stretch at the end period after the contrast period just before the end of the fluorescence contrast imaging after a considerable amount of time has elapsed since the start of the late contrast period. Showing the state of the ring.

In stretching the histogram, for example, the positions A1 and A2 indicating the stretching range in FIG.
, Respectively, are entirely stretched in the directions indicated by the arrows to enhance the contrast. That is, the stretching range immediately after the late contrast period shown in FIG. 4 is continuously changed to the stretching range at the end period after the contrast period shown in FIG. 5 based on the value measured by the timer 28, and the stretching at that time is performed. Is determined according to the value measured by the timer 28.

The image quality improvement parameter setting unit 30 stores the values measured by the timer 28 and the stretching range used at that time (for example, values of 50 and 200 in the case of 8 bits) in a table format. Has been done. At this time, the time by the timer 28 in the case of using the positions A1 and A2 indicating the stretching range immediately after the late contrast period in FIG.
Position indicating the stretch range in the final period after contrast enhancement in FIG.
The time by the timer 28 when B1 and B2 are used can be stored in advance or can be set by an input means such as a mouse or a keyboard connected to the image quality improvement parameter setting unit 30.

(3) Improvement of S / N ratio by averaging processing Since the contrast late image has little change in the image, temporally continuous images are added and the obtained images are divided by the number of added images. As a result, S / with random noise removed
An image with a good N ratio can be generated. The image quality improvement parameter setting unit 30 stores the value measured by the timer 28 and the number of added images used at that time in a table format.

The image quality improvement parameter is not stored in advance in the image quality improvement parameter setting unit 30, but the image quality improvement parameter is set by an input means such as a mouse or a keyboard (not shown) connected to the image quality improvement parameter setting unit 30. You can also Furthermore, not only ICG fluorescence contrast imaging but also fluorescein fluorescence contrast imaging can be similarly performed.

FIG. 6 is a block diagram of the second embodiment, and FIG.
The same reference numerals as in FIG. CCD camera 22
Is sequentially connected to the A / D converter 23, the image memory 31 for temporarily storing the image data, the display system changing unit 32 for changing the image display system, the D / A converter 33, and the television monitor 34. ing. On the other hand, the output of the timer 28 is connected to the timer data setting unit 29, the character generating unit 35, and the display method setting unit 36, and the timer data setting unit 2
9. The output of the display system setting unit 36 is connected to the display system changing unit 32, and the output of the character generating unit 35 is connected to the television monitor 34 via the D / A converter 33.

In the above-mentioned structure, as in the first embodiment, ICG is intravenously injected to the subject, at the same time, the timer 28 is started, and when fluorescence appears on the fundus of the subject's eye, a photographing switch (not shown) is pressed. The timer data at the time of shooting is measured by the timer 28, and is converted into character data by the character generator 35 each time, and then sent to the D / A converter 33.

The photographed image is photoelectrically converted by the CCD camera 22 connected to the fundus camera 21, converted into digital data by the A / D converter 23, stored in the memory 31, and further displayed by the display system changing section 32. After being input to D /
It is sent to the A converter 33 and displayed on the television monitor 34 as shown in FIG. 7 together with the timer data.

The display system setting unit 36 for setting the display system in the display system changing unit 32 has the image memory 31 in advance.
The image transferred from the device is set to be transferred to the D / A converter 33 as it is, and the setting to the display method setting unit 36 may be programmed in advance, or data such as a keyboard or a mouse may be set. You may comprise so that it may set using an input means.

In ICG fluorescence contrast imaging, the time for changing from the initial image to the later image is set in advance in the timer data setting unit 29, and when the time measured by the timer 28 has passed the set time, the display system changing unit 32 causes the timer to change. Upon receiving a display system change command from the data setting unit 29, the display system of the transferred image is changed according to the display system set in the display system setting unit 36.

The data setting in the timer data setting unit 29 may be programmed in advance, or may be configured by using a data input means such as a keyboard or a mouse (not shown). In addition, the display system changing unit 32
The display method is changed by the time set in the timer data setting section 29, but it can be changed by a change execution switch (not shown) connected to the display method changing section 32. is there.

Further, a display switching unit (not shown) is connected to the display system changing unit 32, and this display switching unit receives a display system changing command from the timer data setting unit 29, and based on this command, the display system changing unit 32. Is switched from the through mode in which the display method is not changed to the mode in which the display method is changed, and the image transferred from the image memory 31 to the display method changing unit 32 thereafter is displayed in the display method setting unit 36. The display method may be changed according to the above.

For example, if the timer data setting unit 29 is set to 15 minutes and 30 seconds, the time measured by the timer 28 is 15 minutes and 3 seconds.
When the time reaches 0 seconds, the timer data setting unit 29 issues a display switching command to the display switching unit by a command or an electric level change by an interface connecting the both. The display switching unit that receives this command is the display system changing unit 32.
On the other hand, the display mode setting unit 36 is instructed to change the display according to the set mode, thereby changing the display mode of the fluorescence contrast image input to the display mode changing unit 32 thereafter.

The display system changing unit 32 changes the display system as follows. (1) 'Change by LUT FIG. 8 shows the LUT used when changing the display method.
Similar to FIGS. 2 and 3, the horizontal axis represents the input image level and the vertical axis represents the output image level after the display system is changed.

FIG. 8A shows an LU used immediately after the time set in the timer data setting unit 29 has elapsed from the beginning of contrast enhancement.
FIG. 8 (c) is a LUT used immediately before the end of the fluorescence contrast imaging after a considerable amount of time has passed since the start of the latter stage of the contrast.
Is shown. Then, from the shape of the LUT shown in FIG.
During the process up to the shape of the LUT, the specific LUT shape is changed linearly through the state of FIG. 8 (b) based on the value measured by the timer 28.
It is uniquely determined according to the value clocked in.

In the image of the LUT of FIG. 8 (a), the density level near the center is emphasized, whereas in the latter stage of contrast, the entire gray level in the narrow range between black and white contains many gray levels. In order to obtain an image, as shown in the LUT of FIG. 8C, the density level is changed so that only the density level near the center is emphasized.

In the display system setting section 36, the correspondence between the value measured by the timer 28 and the value of the LUT used at that time is shown in a table format. For example, the timer 28
L used when the value measured in 10 minutes 15 seconds
What the UT looks like is stored in a table format of output image levels versus input image levels. At this time, the time of the timer 28 using the LUT of FIG. 8 (a) and the time of the timer 28 using the LUT of FIG. 8 (c) are stored in advance, or the display method setting unit 36 is set. It can be set by a connected input means such as a mouse or a keyboard (not shown).

In the above description, the central value of the input level is changed by the LUT, but it can be changed by the LUT which is offset to the black side or the white side. Further, the image quality improvement parameter setting unit 3 may be modified by using an LUT having the same S-shaped characteristic as that of the first embodiment.
In the case of 0, the parameter may be set by using the LUT shape as a function having time as a variable.

Also, using an LUT as shown in FIG.
Negative / positive inversion may be performed so that the dark portion and the light portion of the image are inverted to make it easier to see the dark portion of the image. Here, the horizontal axis represents the density level of the image before the change, and the vertical axis represents the density level of the image after the change. Further, the image quality improvement parameter may be set by an input means such as a mouse or keyboard (not shown) connected to the image quality improvement parameter setting unit 30,
Not only ICG fluorescence contrast imaging but also fluorescein fluorescence contrast imaging can be performed in the same manner.

(2) 'Superimposition display with image photographed by infrared transmission filter As shown in FIG. 10, the image photographed in the later stage of fluorescence is the blood vessel, hemorrhagic spot, white spot, photocoagulation spot, and other parts of the fundus. Since the positional relationship of No. is unknown, a fundus image of the same eye to be inspected, which is pre-stored in the memory 31 or the like in this image by the infrared transmission filter as shown in FIG. 7, is shown in FIG. By displaying them in an overlapping manner, their positional relationship can be clarified. Note that there are methods such as watermark composition and mask pattern for superimposing images.
In the watermark composition method, an image in the latter stage of fluorescence and an image captured by an infrared transmission filter can be displayed simultaneously by changing the ratio of display density.

In the present embodiment, from the initial stage of contrast enhancement to immediately after the time set by the timer data setting unit 29 has elapsed,
The density display ratio between the image in the latter stage of fluorescence and the image obtained by the infrared transmission filter is set to a large value, for example, 7: 3, and the density ratio in the latter stage of fluorescence is set to a large value, and a considerable time has elapsed from the beginning of the latter stage of the contrast imaging. Immediately before the end, conversely, the density display ratio is set to, for example, 3 to 7, and the density ratio of the image by the infrared transmission filter is set to increase.

By continuously changing during this period based on the value measured by the timer 28, a specific concentration ratio can be uniquely determined according to the value measured by the timer 28. Note that the density ratio can be determined to an arbitrary value such as 6: 4 or 2: 8 depending on which image should be clearly displayed. In the case of the density ratio of 1: 1, each image can be determined. Shows that each of them was half the density value and then superposed.

Further, by using a mask pattern as shown in FIG. 12, the images can be displayed alternately in black and white by the adjacent pixels, so that the images can be combined. FIG.
FIG. 12A shows a mask pattern used immediately after the time set in the timer data setting unit 29 has passed from the initial stage of contrast enhancement, and FIG. The mask pattern used immediately before the end of contrast imaging is shown. In each mask pattern, data corresponding to each position of the image in the latter stage of fluorescence is arranged in the white part, and data corresponding to each position of the image photographed by the infrared transmission filter is arranged in the black part.

In the present embodiment, between the pattern shape of FIG. 12 (a) and the pattern shape of FIG. 12 (c),
Based on the value measured by the timer 28, FIG.
By continuously changing so as to go through the state of (b), the specific pattern shape is uniquely determined according to the value measured by the timer 28. The type of the mask pattern may be a pattern in which the size of the grating is partially different, and the mask pattern is not an image captured by an infrared transmission filter but is composed of data such as R, G, and B. Image data such as a G image of a color image may be used.

As described above, by changing the image display method according to the timer data, the fluorescent image for each time is automatically generated in the later image at the time of fluorescence contrast imaging without being aware of the time of the timer. It is possible to perform display by a display method suitable for the image.

FIG. 13 shows the configuration of the third embodiment, and the same reference numerals as those in FIGS. 1 and 6 represent the same members. The output of the CCD camera 22 is sequentially connected to the character synthesizing section 37, the image quality improving section 25, the video tape recorder 38, and the television monitor 34, and the output of the timer 28 is sent to the character synthesizing section 37 via the character generating section 35. Connected,
Further, it is connected to the image quality improving unit 25 via the timer data setting unit 29.

In the above-mentioned structure, ICG is intravenously injected into the subject and the timer 28 is started at the same time as in the first embodiment. Then, when the recording switch of the video tape recorder 38 is pressed, the fluorescence contrast image of the subject's eye photoelectrically converted by the CCD camera 22 is input to the character synthesizing unit 37.

On the other hand, the timer data counted by the timer 28 is continuously sent to the character generating section 35,
The character combination unit 37 combines the character data with the fluorescence contrast image. The combined image is input to the image quality improving unit 25, then recorded on the video tape recorder 38, and simultaneously displayed on the television monitor 34 as a moving image.

In ICG fluorescence contrast imaging, the time for changing from the initial image to the later image is set as a threshold value in the timer data setting unit 29 in advance, and when the time measured by the timer 28 exceeds the set threshold time, the image quality is improved. A processing switching unit (not shown) connected to the unit 25 receives a processing start command from the timer data setting unit 29, and switches the image quality improving unit 25 from a non-processing mode to a processing mode based on the command. The image quality improving process in the image quality improving unit 25 is started.

For example, if the timer data setting unit 29 sets 15 minutes and 30 seconds as the threshold time, after the timer 28 reaches the threshold time, the timer data setting unit 29 causes the image quality improving unit 25 to perform processing. The switching unit is automatically instructed to start processing by a command from the interface connecting them or an electric level change.
In response to this instruction, the image quality improving unit 25 executes the image quality improving process on the fluorescence contrast image image input after the threshold time according to the preset image quality improving process.

The method of image quality improvement processing may not be set in advance, but may be set by an instruction from the timer data setting unit 29, and the setting of data in the timer data setting unit 29 may be performed in advance. It may be programmed or may be configured to be set by using a data input means such as a keyboard or a mouse.

The image quality improving process in the image quality improving unit 25 is performed as follows. (1) “Contrast enhancement by LUT” As in the first embodiment, the LUT shown in FIG. 3 is used to enhance the dark part or the light part of the image, and most of the data in the middle part is distributed to either light or dark. , Enhance the contrast of the image.

(2) "Contrast enhancement by stretching of histogram Similarly, in the density histogram as shown in FIG.
Contrast enhancement of the image is performed by extending necessary image information components to the dark side and the bright side, respectively, as indicated by arrows in the figure.

(3) Improvement of S / N ratio by averaging processing In the latter period image of contrast, temporally continuous images are added and divided by the number of added images to obtain the S / N ratio from which random noise is removed. It can generate good images.
The number of images to be added may be arbitrary, but normally 3 to 5 is appropriate.

Data such as parameters used for changing the above-mentioned display system may be set by the display system setting unit 36, and the same applies not only to ICG fluorescence contrast imaging but also to fluorescein fluorescence contrast imaging. It can be carried out.

In this way, by changing the display method after the threshold time set by the timer data setting means, it is necessary to be aware of the time when the display method is changed to make the image easier to see in the later period of the fluorescence contrast enhancement image. Instead, it is possible to reliably display an easily viewable image after an appropriate time.
Further, by changing the display method and combining and displaying with the image photographed by the infrared transmission filter, it is possible to grasp the situation of the fundus in detail.

FIG. 14 is a block diagram of the fourth embodiment, in which the same symbols as in the previous embodiment represent the same members. The output of the CCD camera 22 connected to the fundus camera 21 is A / D.
The converter 23, the image memory 31, which is composed of a volatile memory such as RAM, the D / A converter 33, and the television monitor 34 are sequentially connected, and the output of the image memory 31 is a hard disk via the digital interface 26. It is connected to 27. The output of the timer 39 built in the fundus camera 21 is connected to the television monitor 34 via the timer data storage unit 40 and the D / A converter 33, and the timer data setting unit 41, the thinning processing unit 42, and the digital interface 26. Is connected to the hard disk 27 via.

In the above structure, first, as in the first embodiment, ICG is intravenously injected to the subject, and at the same time, the fundus camera 21.
The timer 39 is started by pressing a timer start switch (not shown). The photographer observes an output image of the CCD camera 22 and the like from a finder unit (not shown) connected to the fundus camera 21 and presses a photographing switch (not shown) on the fundus camera 21 when fluorescence appears on the fundus of the subject. The timer data at the time of shooting is measured by the timer 39, and each time,
It is stored in the timer data storage unit 40.

The photographed image is photoelectrically converted by the CCD camera 22, converted into digital data by the A / D converter 23, and stored in the image memory 31. At the same time, this image reaches the television monitor 34 via the D / A converter 33 and is confirmed by the photographer. Then, the image memory 31
The above image is stored in the hard disk 27 via the digital interface 26 together with the timer data stored in the timer data storage unit 40.

In ICG fluorescence contrast imaging, if the time for changing from the initial image to the later image is set as a threshold value in the timer data setting section 41 in advance, when the imaging time exceeds the set threshold time, The image data from the image memory 31 is subjected to thinning processing by a predetermined thinning method in the thinning processing unit 42, and the interface 26
Transferred to

The data setting in the timer data setting section 41 may be programmed in advance, or may be set using a data input means such as a keyboard or a mouse. Further, similarly to the case of setting the timer data, with respect to the thinning-out method in the thinning-out processing unit 42, the thinning-out rate at which the thinning-out is performed can be arbitrarily set.

In the above description, the thinning process is performed when the image data stored in the image memory 31 is transferred to the hard disk 27, but the output of the CCD camera 22 is transferred from the A / D converter 23 to the image memory 31. It may be configured to perform the thinning-out process when the data is stored in.

A data compression processing unit may be provided instead of the thinning processing unit 42 to perform compression processing of image data. In this case, J is the data compression method.
Using PEG, LZW, or the like, the compression rate can be arbitrarily changed in the same manner as the thinning rate described above.

Further, instead of the thinning-out processing section 42, a peripheral image addition / averaging processing section may be provided to perform addition / averaging processing of the peripheral images. This peripheral image addition and averaging processing includes a method of thinning out the entire image using the addition average value of two adjacent pixels, and a method of thinning the entire image using the addition average value of the surrounding four or eight pixels.

A density gradation changing unit may be provided instead of the thinning processing unit 42 to change the density gradation. In this case, for example, the density gradation is compressed in the latter image of the ICG fluorescence contrast imaging.

In this way, by processing the images input after the threshold value set by the timer data setting means so as to reduce the point of the image, it is necessary for the initial image and the later image in the fluorescence contrast imaging. It is possible to suppress the loss of various information and efficiently use the memory area. Further, by performing the arithmetic mean of the peripheral images as the image processing means, it is possible to improve the image even for the conventional late image having a poor S / N ratio.

The image processing of the above-described embodiment can be carried out not only for ICG fluorescence contrast imaging but also for fluorescein fluorescence contrast imaging.

[0086]

As described above, the ophthalmic image processing apparatus according to the first aspect of the present invention improves the image quality of the input image according to the timer data, so that the time of the timer is increased in the later image at the time of fluorescence contrast imaging. It is possible to automatically perform the image quality improvement processing suitable for the fluorescence contrast image at each time without being aware of the above.

Further, the ophthalmic image processing apparatus according to the second aspect of the present invention performs the image quality improvement process after the threshold time set by the timer data setting means, so as to be aware of the time when the image quality improvement process of the fluorescence contrast enhancement late image is performed. Instead, it is possible to reliably record the image for which the image quality improvement processing has been performed after an appropriate time.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a first embodiment.

FIG. 2 is a LUT for contrast enhancement processing immediately after the latter period of contrast enhancement.
FIG.

FIG. 3 is a graph diagram of an LUT of contrast enhancement processing after the end of contrast period.

FIG. 4 is a graph diagram of histogram stretching processing immediately after the latter period of contrast enhancement.

FIG. 5 is a graph of a post-contrast end period histogram stretching process.

FIG. 6 is a configuration diagram of a second embodiment.

FIG. 7 is an explanatory diagram of a fundus image.

FIG. 8 is a graph of a LUT for contrast enhancement processing.

FIG. 9 is a graph of a negative / positive inversion LUT.

FIG. 10 is an explanatory diagram of a fluorescent late fundus image.

FIG. 11 is an explanatory diagram of a superimposed fundus image.

FIG. 12 is a front view of a mask pattern.

FIG. 13 is a configuration diagram of a third embodiment.

FIG. 14 is a configuration diagram of a fourth embodiment.

FIG. 15 is a configuration diagram of a first conventional example.

FIG. 16 is a configuration diagram of a second conventional example.

FIG. 17 is a configuration diagram of a third conventional example.

FIG. 18 is a configuration diagram of a fourth conventional example.

[Explanation of symbols]

 21 fundus camera 22 CCD camera 24 data processing unit 25 image quality improving unit 27 hard disk 28, 39 timer 29, 41 timer data setting unit 30 image quality improving parameter setting unit 31 image memory 32 display method changing unit 34 TV monitor 35 character generating unit 36 display Method setting unit 37 Character combining unit 38 Video tape recorder 40 Timer data storage unit 42 Thinning processing unit

Claims (21)

[Claims] 1. An image input unit for inputting a fluorescent fundus image, a timer for counting the time when an image is input to the image input unit, and an input by the image input unit in association with timer data measured by the timer. An image processing apparatus for ophthalmology, comprising: an image processing unit that applies a predetermined process to the captured image. 2. The ophthalmic image processing apparatus according to claim 1, wherein the fluorescent fundus image is an ICG fluorescent fundus image. 3. The ophthalmic image processing apparatus according to claim 1, wherein the image processing means is image quality improvement processing means for improving the image quality of an image. 4. The ophthalmic image processing apparatus according to claim 3, wherein the image quality improvement processing unit is a contrast enhancement processing unit using a lookup table. 5. The ophthalmic image processing apparatus according to claim 3, wherein the image quality improvement processing unit is a contrast enhancement processing unit by stretching a histogram. 6. The ophthalmic image processing apparatus according to claim 3, wherein the image quality improvement processing unit is image averaging processing unit. 7. The image display method changing means for changing the display method of the image input by the image input means, and the image display means for displaying the image changed by the image display method changing means. The described ophthalmic image processing device. 8. An image storage unit for storing a fundus image of the same eye as the image input by the image input unit,
The ophthalmic image processing apparatus according to claim 7, wherein the display method by the image display method changing unit is changed to a combined display of an image input by the image input unit and an image stored in the image storage unit. 9. An image input means for inputting a fluorescent fundus image, a timer for counting the time when an image is input to the image input means, a timer threshold setting means for setting a threshold value for the timer, and the timer threshold setting means. An image processing apparatus for ophthalmology, comprising: an image processing unit that applies a predetermined process to an image input from the image input unit based on the threshold value set in step 2. 10. An image display method setting means for setting a display method of an image input by the image input means, and an image display means for displaying an image according to the display method set by the image display method setting means. The ophthalmic image processing device according to claim 9. 11. An image storage means for storing a fundus image of the same eye to be examined as the image input by the image input means is provided, and the image display method setting means stores the image input by the image input means and the image storage means. The ophthalmic image processing apparatus according to claim 10, wherein composite display with the stored image is set. 12. The ophthalmic image processing apparatus according to claim 9, wherein the fluorescent fundus image is an ICG fluorescent fundus image. 13. The ophthalmic apparatus according to claim 12, wherein the image processing means is an image quality improvement processing means for improving the image quality of the image, and an image recording means for recording the image improved in image quality by the image quality improvement processing means is provided. Image processing device. 14. The ophthalmic image recording apparatus according to claim 13, wherein the image quality improvement processing unit is a contrast enhancement processing unit using a lookup table. 15. The ophthalmic image recording apparatus according to claim 13, wherein the image quality improvement processing unit is a contrast enhancement processing unit by stretching a histogram. 16. The ophthalmic image recording apparatus according to claim 12, wherein the image quality improvement processing unit is an image averaging processing unit. 17. The ophthalmic image processing apparatus according to claim 9, wherein the image processing means is image capacity reduction processing means for reducing the image capacity. 18. The ophthalmic image processing apparatus according to claim 17, wherein the image capacity reduction processing means is image data thinning processing means. 19. The ophthalmic image processing apparatus according to claim 17, wherein the image capacity reduction processing means is image data compression processing means. 20. The ophthalmic image processing apparatus according to claim 17, wherein the image capacity reduction processing unit is a peripheral image addition averaging processing unit. 21. The ophthalmic image processing apparatus according to claim 17, wherein the image capacity reduction processing means is image density gradation change processing means.