Endoscopic apparatus

Abstract

Provided is an endoscopic apparatus 1 applicable to various objects or the like.　The endoscopic apparatus 1 includes: an endoscope 10 having an imaging unit 15; an image processing circuit 31 for generating an image of an object; a calculation circuit 32 for calculating an index by normalizing a sum of a red pixel value and a green pixel value of each pixel of the image of the object by twice a blue pixel value; a memory 50 for storing a plurality of thresholds for identifying three or more pathological levels in a plurality of regions of the object, and identification colors corresponding to the pathological levels; an identification circuit 33 for identifying a pathological level from the index; an identification color acquisition circuit 34 for acquiring the identification color corresponding to the pathological level; an image generation circuit 35 for generating an identified image using the identification colors; and a monitor 40 for displaying the identified image.

Description

Endoscopic Devices

[0001] The present invention relates to an endoscope apparatus for capturing images of an object inside a body.

[0002] International Publication No. 2018 / 230130 discloses an endoscope device that calculates an index indicating the degree of abnormality of a subject based on the color contained in an image of the subject captured with an endoscope, and identifies and displays the index based on a threshold value.

[0003] International Publication No. 2018 / 230130

[0004] However, in the above-mentioned endoscope device, the index indicates the degree of abnormality as either abnormal or normal. Also, because the threshold for identifying the index is simple, there is a risk that the applicable subjects may be limited.

[0005] An object of the present invention is to provide an endoscope apparatus that can distinguish and display three or more symptom levels and that can be applied to many subjects.

[0006] An endoscopic device according to an embodiment of the present invention includes an endoscope having an imaging unit that images at least one subject inside the body of a subject and outputs an image signal; an image processing unit that performs image processing on the image signal to generate a subject image; a calculation unit that calculates an index for each pixel by normalizing the sum of red and green pixel values ​​of each of a plurality of pixels in at least a partial region of the subject image by twice the blue pixel value; a memory that stores a plurality of thresholds for classifying a plurality of regions of the subject into one of three or more symptom levels and discrimination colors corresponding to each of the plurality of symptom levels; a discrimination unit that discriminates the symptom level of each pixel based on the index using the plurality of thresholds; a discrimination color acquisition unit that acquires the discrimination color corresponding to the symptom level of each pixel; an image generation unit that generates a discrimination image using the discrimination colors of each of the plurality of pixels; and a monitor that displays the discrimination image.

[0007] According to the present invention, an endoscope apparatus that can distinguish and display three or more symptom levels can be provided, and that can be applied to many subjects.

[0008] FIG. 1 is a diagram showing the configuration of an endoscopic device according to an embodiment of the present invention. FIG. 2 is a diagram illustrating the relationship between the absorption characteristics of plasma and the emission characteristics of a light source. FIG. 3 is a diagram illustrating the absorption characteristics of a subject. FIG. 4 is a diagram illustrating a calculation formula for an index of the endoscopic device according to an embodiment of the present invention. FIG. 5 is a diagram illustrating a calculation formula for an index of the endoscopic device according to an embodiment of the present invention. FIG. 6 is a flowchart of an operation method of the endoscopic device according to an embodiment of the present invention. FIG. 7 is a diagram illustrating the relationship between a symptom level and a threshold value in the endoscopic device according to an embodiment of the present invention. FIG. 8 is a diagram illustrating the relationship between a symptom level and a threshold value set in the endoscopic device according to an embodiment of the present invention. FIG. 9 is a diagram illustrating the relationship between a symptom level and a discrimination color in the endoscopic device according to an embodiment of the present invention. FIG. 10 is a display example 1 of a monitor screen of the endoscopic device according to an embodiment of the present invention. FIG. 11 is a display example 2 of a monitor screen of the endoscopic device according to an embodiment of the present invention. FIG. 12 is a display example 3 of a monitor screen of the endoscopic device according to an embodiment of the present invention. FIG. 13 is a display example 4 of a monitor screen of the endoscopic device according to an embodiment of the present invention. FIG. 14 is a display example 5 of a monitor screen of the endoscopic device according to an embodiment of the present invention. Fig. 15 shows a sixth display example of the monitor screen in the endoscope apparatus according to the embodiment of the present invention. Fig. 16 shows a seventh display example of the monitor screen in the endoscope apparatus according to the embodiment of the present invention.

[0009] <Configuration of Endoscope Apparatus> As shown in FIG. 1 , an endoscope apparatus 1 of the embodiment includes an endoscope 10 , a light source device 20 , a processor 30 , a monitor 40 , and a memory 50 .

[0010] The endoscope 10 has an elongated insertion section 11 to be inserted into the subject 90, an operation section 12 provided at the proximal end of the insertion section 11, a universal cord 13 extending from the operation section 12, and a connector 14. The operation section 12 has a plurality of buttons 12A and the like which are endoscope setting sections for operating the endoscope functions and the imaging functions. The insertion section 11 of the endoscope 10 has, in order from the distal end, a distal end portion 11A, a bending section 11B provided at the proximal end of the distal end portion 11A, and an elongated flexible tube 11C provided at the proximal end of the bending section 11B. The distal end portion 11A is provided with an imaging unit 15 which is an imaging section and an illumination unit 16 which is an illumination section.

[0011] The connector 14 of the endoscope 10 is connected to the light source device 20 and the processor 30. Illumination light L generated by the light source device 20 is guided to the illumination unit 16 at the tip 11A of the insertion section 11 and illuminates an object 91 inside the body of the subject 90. The imaging unit 15 has an imaging element such as a CCD. The imaging unit 15 converts reflected light R from the object 91 into an electrical signal and outputs an image of the object to the processor 30.

[0012] The light source device 20 includes a light source control unit 22 , a light source 23 , and a multiplexer 24 .

[0013] The light source control unit 22 is a light source control circuit that is connected to the light source 23 and controls the light source 23 in response to a control signal from the processor 30 .

[0014] The light source 23 has a plurality of light-emitting elements such as LEDs. The light source 23 has an R element 23R, a G element 23G, and a B element 23B. The R element 23R emits red light Br in a normal band. The G element 23G emits green light Bg in a normal band. The B element 23B emits blue light Bb in a normal band. The B element 23B not only outputs the normal blue light Bb, but also narrows the band of the blue light using, for example, a narrow-band optical filter (not shown), and outputs narrow-band blue light Nb.

[0015] The multiplexer 24 multiplexes the multiple light beams input from the light sources 23 and outputs the illumination light L to the illumination unit 16 .

[0016] The processor 30 has an image processing unit 31, a calculation unit 32, a discrimination unit 33, a discrimination color acquisition unit 34, an image generation unit 35, and a setting unit 36. The processor 30, which is made up of a CPU, controls the entire endoscopic device 1, generates an endoscopic image based on an imaging signal input from the endoscope 10, and generates a discrimination image based on the endoscopic image, as described below.

[0017] The setting unit 36, which is a setting circuit, is a button or the like through which the user inputs various instructions. The setting unit 36 ​​may be a touch panel, a keyboard, a foot switch, or the button 12A of the endoscope 10, which is separate from the processor 30. For example, instructions such as an instruction to bend the bending portion, an instruction to drive the light source device 20, the type of illumination light L that illuminates the subject 91, the type of observation portion of the subject 91, and an image to be displayed on the monitor 40 are input from the setting unit 36.

[0018] The configurations of the image processing unit 31, the calculation unit 32, the discrimination unit 33, the discrimination color acquisition unit 34, and the image generation unit 35 will be described later.

[0019] At least one of the multiple configurations of the processor 30 and the light source control unit 22 may be configured by the processor 30 or the internal circuit (CPU) of the light source device that operates by software (program), or may be configured by a dedicated hardware circuit.

[0020] The monitor 40 is, for example, a liquid crystal display (LCD) or a CRT that displays a color image. The monitor 40 displays an image instructed by the processor 30. The monitor 40 having a touch panel function may constitute a part of the setting unit 36.

[0021] The memory 50 is a RAM, a ROM, a hard disk drive, or the like that stores data such as operating conditions of the processor 30, programs, and the like. The memory 50 may be an internal memory of the processor 30 to which data, and the like, is transferred and stored from a non-transitory computer-readable storage medium such as a CD or DVD. The processor 30 performs predetermined processing based on the programs and data stored in the memory 50. Furthermore, past examination data of the subject 90, and the like, stored in, for example, a server separate from the endoscope device 1, may be transferred to the memory 50 via an internet line, or the like.

[0022] The calculation unit 32 is a calculation circuit that calculates an index VI for each of a plurality of pixels of the subject image output by the imaging unit. The index VI, which quantitatively indicates the symptom level of the subject 91, is calculated using a predetermined calculation formula.

[0023] The process for selecting the calculation formula will be explained below. Fig. 2 is a diagram illustrating the relationship between the light absorption characteristic W of plasma and the wavelength of light emitted by the light source 23. Fig. 2 shows normal band red light Br, normal band green light Bg, normal band blue light Bb, narrow band blue light Nb, the light absorption characteristic W of plasma, and the peak wavelength Wp of the absorption coefficient of plasma.

[0024] As shown in FIG. 2, the absorption characteristic W of plasma is low at a wavelength of about 415 nm, peaks at a wavelength of about 465 nm, and approaches 0 at a wavelength of about 550 nm.

[0025] Therefore, while blue light Bb may be in a normal band, in order to detect plasma significantly, it is particularly preferable that the band be narrowed so that the central wavelength is the same as the peak wavelength Wp of the absorption coefficient of plasma. For example, blue light Bb is narrowed so that the central wavelength is around 465 nm and used as narrow-band blue light Nb. Blue light Bb may also be narrowed so that the central wavelength is 460 nm to 470 nm. Furthermore, blue light Bb may also be narrowed so that the central wavelength is 415 nm to 495 nm.

[0026] When irradiated with special light including red light Br, green light Bg, and narrow-band blue light Nb, the blood plasma absorbs more blue light than red and green light, and appears more yellow than when irradiated with normal light including normal blue light Bb.

[0027] Next, Fig. 3 shows a schematic cross section of a mucosa. Shown in Fig. 3 are normal mucosa N, edema M, polyp S, blood vessels Bv, and illumination light L. Here, illumination light L is monochromatic light with a short wavelength, such as narrowband blue light Nb. The pigment in the mucosa is plasma.

[0028] As shown in the light penetration area L1, the penetration of illumination light L is high in normal mucosa N, and reflected light R appears pale yellow due to intramucosal pigments that have a higher absorption coefficient on the short wavelength side than on the long wavelength side.

[0029] As shown in the light penetration region L2, the penetration of illumination light L is reduced in edema M compared to normal mucosa N. More specifically, in edema M, illumination light L is scattered more at short wavelengths than at long wavelengths by the thickened epithelium, and is reflected without being absorbed by the pigment in the mucosa. Therefore, reflected light R appears whiter in edema M than in normal mucosa N.

[0030] As shown in the light penetration region L3, the degree of light penetration in the polyp S is even lower than in the edema M, and the reflected light R appears even whiter than in the edema M.

[0031] 4 shows an index VI obtained by normalizing the green pixel value Vg, red pixel value Vr, blue pixel value Vb, or the sum of the green pixel value Vg and the red pixel value Vr of a pixel included in an endoscopic image. The pixel value V is obtained as, for example, 8-bit data (0-255).

[0032] Fig. 4 shows the difference in index VI due to differences in the calculation formula for index VI among normal mucosa N, edema M, and polyp S. In Fig. 4, "Vg / Vb," "Vr / Vb," "Vr / Vg," and "(Vr+Vg) / 2Vb" on the X-axis each represent the calculation formula for index VI, and the Y-axis represents the index VI normalized by each calculation formula.

[0033] The solid line indicates normal mucosa N, the dashed-dotted line indicates edema M, and the dashed-two-dotted line indicates polyp S. Hereinafter, edema M and polyp S will be referred to as abnormal mucosa.

[0034] In the mucosa of the body, for example, the mucosa of the nasal sinuses, the symptom levels increase in order of normal mucosa N, edema M, and polyps S. There is a difference in color between normal mucosa N and abnormal mucosa, and as the symptom level increases, the mucosal epithelium becomes thicker and the appearance becomes whiter. Therefore, the calculation formula that gives the largest index VI for normal mucosa N and the largest index VI for polyps S is "(Vr + Vg) / 2Vb."

[0035] Figure 5 shows the index VIN for edema M and polyp S, obtained by normalizing the index VI for edema M and polyp S, which are the same as those in Figure 4, by the index VI for normal mucosa N. In Figure 5, the X-axis shows the formula used to calculate the index VIN normalized by the index VI for normal mucosa N, and the Y-axis shows the index VIN.

[0036] As shown in Figures 4 and 5, for normal mucosa N and polyp S, the indices VI and VIN calculated using the calculation formula "(Vr + Vg) / 2Vb" are greater than the indices VI and VIN calculated using other index calculation formulas.

[0037] That is, the indices VI and VIN calculated by the calculation formula "(Vr+Vg) / 2Vb" largely represent the difference in color between the normal mucosa N and the abnormal mucosa.

[0038] <Operation Method of Endoscope Apparatus> The operation method of the endoscope apparatus 1 will be described with reference to the flowchart of FIG.

[0039] <Step S10> Illumination Light Irradiation The insertion section 11 of the endoscope 10 is inserted into the living body of the subject 90, for example, into the nasal cavity. Illumination light L from the light source device 20 is irradiated onto the mucous membrane, which is the subject 91, via the illumination unit 16 at the tip section 11A. The illumination light L is red light Br, green light Bg, and blue light Bb.

[0040] <Step S20> Output of Image Signal The image pickup unit 15 of the tip portion 11A receives reflected light R from the subject 91, converts it into an electrical signal, and outputs the image pickup signal to the processor 30.

[0041] <Step S30> Image processing The image processing unit 31 is an image processing circuit that performs image processing such as gain adjustment, white balance adjustment, gamma correction, contour emphasis correction, and zoom adjustment based on the imaging signal to generate an endoscopic image, which is an image of the subject.

[0042] <Step S40> Calculation of Index The calculation unit 32 calculates the index VI for each pixel by normalizing the sum of the red pixel value Vr and the green pixel value Vg for each of the multiple pixels in the subject image by twice the blue pixel value Vb (Nb). In other words, the calculation unit 32 calculates the index VI for multiple regions (pixels) of the subject.

[0043] 4 and 5, the formula "(Vr+Vg) / 2Vb" is used to normalize pixel values ​​and calculate the index VI. However, the formula can be changed as appropriate as long as it normalizes the sum of red and green pixel values ​​by twice the value of the blue pixel value.

[0044] For example, the indicator VI may be converted into 8-bit (0-255) data, an additional value may be added to the 8-bit data, or the k value in the calculation formula "(Vr+Vg) / kVb" may be changed. In the following, the indicator VI is calculated using Formula 1.

[0045] <Formula 1> VI=32×log2[(Vr+Vg) / 2Vb]+256

[0046] The calculation unit 32 preferably calculates the index VI using one of a plurality of calculation formulas corresponding to each of a plurality of subjects 91 (for example, the nasal sinuses, the digestive tract).

[0047] <Step S50> Symptom Level Identification The identification unit 33 is an identification circuit that identifies the symptom level of each pixel using a plurality of threshold values ​​T based on the index VI.

[0048] In the endoscope device 1, there are five symptom levels: "normal / mild / moderate / severe / very severe." If there are three or more symptom levels, it is easier to determine the detailed symptoms than if there are only two levels: "normal / abnormal."

[0049] In order to distinguish between five symptom levels, four thresholds T (a first threshold T1 for distinguishing between normal and mild symptoms, a second threshold T2 for distinguishing between mild and moderate symptoms, a third threshold T3 for distinguishing between moderate and severe symptoms, and a fourth threshold T4 for distinguishing between severe and extremely severe symptoms) are required. The thresholds T are appropriately set in advance based on the judgments of multiple experts. It goes without saying that the magnitude relationship of the four thresholds T, each set within a predetermined range, is in the order of T1 to T4.

[0050] 7 shows an example of the threshold value T. It is preferable that the differences ΔT between multiple threshold values ​​are approximately the same. For example, it is preferable that the difference ΔT3 (threshold value T4-threshold value T3) is 80% or more and 120% or less of the difference ΔT2 (threshold value T3-threshold value T2).

[0051] However, depending on the conditions, the first threshold difference ΔT1 between the first threshold T1 and the second threshold T2 may be larger than the second threshold difference ΔT2 between the second threshold T2 and the third threshold T3, and the second threshold difference ΔT2 may be larger than the third threshold difference ΔT3 between the third threshold T3 and the fourth threshold T4. Conversely, the first threshold difference ΔT1 may be smaller than the second threshold difference ΔT2, and the second threshold difference ΔT2 may be smaller than the third threshold difference ΔT3.

[0052] Furthermore, depending on the system to be combined and the imaging device to be installed, the threshold difference ΔT may become larger as the severity of the condition increases.

[0053] The memory 50 stores a plurality of threshold sets, each consisting of a plurality of thresholds, corresponding to each of the plurality of subjects 91, and the classification unit 33 performs classification using the threshold set corresponding to the subject 91. The threshold set used by the classification unit 33 may be automatically acquired or may be set by the setting unit 36.

[0054] 8, there is variation (dispersion) among the thresholds T (T1-T4) included in the multiple threshold sets, but it is preferable that the variation among the thresholds T (T1-T4) be set within a predetermined range. For example, the maximum value of threshold T1 is 313, and the minimum value of threshold T1 is 291. In contrast, the maximum value of threshold T4 is 273, and the minimum value is 267. In other words, the variation LT1 (= 6) of threshold T4 is smaller than the variation LT2 (= 22) of threshold T1.

[0055] This is due to the color balance calibration performed by the image processing unit 31. That is, the image processing unit 31 performs white balance as color balance calibration, using a white color close to the color of the most severe area as a reference.

[0056] It is possible to adjust the variation in the threshold value T by changing the color used in color balance calibration or by performing calibration using multiple colors. For example, by performing color balance calibration using the color of the normal region (red-yellow), the variation LT2 in the threshold value T1 can be reduced. Furthermore, by performing color balance calibration using an intermediate color between the color of the most severe region and the color of the normal region (red-yellow), the variation in multiple threshold values ​​T can be reduced and averaged.

[0057] <Step S60> Distinguishing Color Acquisition Unit The distinguishing color acquisition unit 34 acquires a distinguishing color according to the symptom level of the pixel acquired by the identification unit 33.

[0058] 9 shows the identification colors according to the symptom levels. The index VI is, for example, data in the range of (0-511) obtained by adding 256 to 8-bit data. A plurality of threshold values ​​T and identification colors are stored in the memory 50.

[0059] In the example of Figure 9, the identification color acquisition unit 34 acquires multiple colors with different hues, but it may also acquire multiple saturations with different vividness, multiple brightness levels with different brightness, multiple hatching with different spacing, or multiple patterns with different patterns.

[0060] Note that an endoscopic image may contain pixels having error pixel values ​​of colors that do not occur in normal imaging. In the endoscope device 1, a pixel having a pixel value V where at least one of the red pixel value, green pixel value, and blue pixel value is less than a predetermined lower limit pixel value or greater than a predetermined upper limit pixel value is considered to be a first error pixel. For example, a pixel having a pixel value V in the range (0-255) that is less than 5 or greater than 250 is considered to be a first error pixel.

[0061] Furthermore, a pixel having an index VI that is equal to or smaller than a predetermined lower threshold or equal to or larger than a predetermined upper threshold is determined to be a second error pixel. For example, in the example shown in FIG. 9, a pixel having an index VI that is equal to or smaller than the lower threshold of 10 or equal to or larger than the upper threshold of 500 is determined to be a second error pixel.

[0062] The discrimination color acquisition unit 34 acquires error colors for error pixels (first error pixel and second error pixel). The image generation unit generates a discrimination image using the error colors for the error pixels. The error colors are not limited to black and white as shown in FIG. 9, but may be, for example, gray. Furthermore, pixels below a lower limit and above an upper limit of a threshold may have the same error color (for example, white). The numerical values ​​of the error pixel determination criteria and the error color data are stored in the memory 50.

[0063] The ratio of the number of error pixels to the total number of pixels (error ratio) may be calculated, and if the error ratio is equal to or greater than a predetermined value, the processor 30 may issue a warning. The number of error pixels may be the number of first error pixels, the number of second error pixels, or the total number of error pixels. The warning may be displayed, for example, in text or graphics on the monitor 40.

[0064] Symptom levels can be easily identified by, for example, changing the threshold set based on the warning, which may be done automatically or by the user.

[0065] <Step S70> Generate a discrimination image The discrimination color acquisition unit 34 acquires a discrimination color corresponding to the symptom level of each pixel. The image generation unit 35 is a discrimination color acquisition circuit that generates a discrimination image using the discrimination colors of each of the multiple pixels.

[0066] <Step S80> Display The monitor 40 displays the identification image in various forms.

[0067] <Display Example 1> Fig. 10 shows an example of a display image on the monitor 40. In Fig. 10, a partial area of ​​an endoscopic image 40A displayed in color is replaced with an identification image 40B. In other words, a superimposed image in which the identification image 40B is superimposed on the endoscopic image 40A is displayed. The area displayed as the identification image 40B is indicated by a frame on the endoscopic image 40A.

[0068] From the viewpoint of visibility and operability, it is preferable that the area of ​​the identification image 40B be 20% to 70% of the area of ​​the entire region of the endoscopic image 40A. The area of ​​the identification image 40B can be changed by operating the setting unit 36, for example.

[0069] Additionally, an index average value 40D is displayed on the monitor 40 together with the discrimination color list display 40C. That is, the calculation unit 32 calculates an index average value 40D for a plurality of pixels, and the monitor 40 displays the index average value 40D.

[0070] The user can easily understand the subject's symptoms based on the average index value of 40D.

[0071] 11 , an identification image 40B is displayed on the monitor 40 in place of the endoscopic image 40A. That is, the calculation unit 32 may calculate an index from a plurality of pixels in the entire area of ​​the endoscopic image 40A, which is the subject image, and the image generation unit 35 may generate an identification image corresponding to the entire area of ​​the endoscopic image 40A.

[0072] 12 , an identification image 40B of a framed area in an endoscopic image 40A is displayed in a separate area from the endoscopic image 40A on the monitor 40. At least one of the position and range (area) of the partial area from which the identification image 40B is generated within the entire area of ​​the endoscopic image 40A, which is the subject image, can be appropriately selected by operating the setting unit 36.

[0073] In a narrow duct, it may not be easy to point the center of the endoscopic image 40A (the center of the field of view of the imaging unit 15) at the region of interest. However, by selecting at least one of the position and range of the region in which the identification image 40B is displayed, the user can easily identify the region of interest.

[0074] <Display Example 4> As shown in Figure 13, the monitor 40 displays, together with the endoscopic image 40A and the identification image 40B, an identification image 40BP, which is a past image of a range similar to the identification image 40B from a previous examination of the subject 90, and an average value 40DP of the index.

[0075] To select the range of the past identified image 40BP based on the identified image 40B, the endoscopic image or pattern matching of the identified image, the state at the time of the examination (for example, the position and direction of the tip of the endoscope), etc. are used.

[0076] The display screen of the endoscopic image 40A and the identification image 40B at the time of the examination and the display screen of the past endoscopic image and the identification image 40BP may be switched between or displayed on separate monitors. It is preferable that the display range and display position of the past identification image 40BP can also be changed as appropriate. The identification images 40BP and the like from past examinations of the subject 90 are stored, for example, in a server in the hospital and transferred to the processor 30.

[0077] Alternatively, the difference between the past identification image 40BP and the identification image 40B at the time of examination may be calculated and displayed. For example, by displaying only pixels where the difference in the index VI for each pixel has increased by a predetermined value or more, it is possible to clearly indicate areas where the condition is changing.

[0078] 10, but in the identification image 40B, only the most severe level red of the five color regions is displayed in color, and the normal level to severe level regions are displayed in a single color, white or gray. Alternatively, the normal level to severe level regions may be displayed as a normal endoscopic image illuminated with white light.

[0079] The level (color) areas displayed in color may be preset, but are preferably configurable as needed. For example, clicking one of the five color areas of the identification color list display 40C changes the level area from the identification color display to a white display, and clicking again changes the white display back to the color display. There may be multiple level areas displayed in color. Furthermore, a normal endoscopic image illuminated with white light may be displayed in the identification image area displayed in white.

[0080] <Display Example 6> The screen of the monitor 40 in Fig. 15 is similar to that in Fig. 10, but unlike Fig. 10, the identification image 40B is made semi-transparent by setting the transmittance and is displayed superimposed on the endoscopic image 40A. When the transmittance is 0%, only the identification image is displayed but not the endoscopic image 40A, and when the transmittance is 100%, only the endoscopic image 40A is displayed but not the identification image 40B.

[0081] Furthermore, the transmittance of each of the five distinguishing colors of the five color regions of the distinguishing image 40B can be set for each distinguishing color. Of course, only the selected distinguishing color may be made semi-transparent.

[0082] To set the translucency of the identification image 40B, for example, the monitor 40 is a touch panel, and pressing and holding each of the five color areas of the identification color list display 40C and sliding it to the left increases the transmittance of the identification color of that level area, and sliding it to the right decreases the transmittance of that identification color.

[0083] (Table 1)

[0084] In Case A of Table 1 above, all identification colors (levels) are set to a transmittance of 50%. In Case B of Table 1 above, the transmittance decreases as the severity level changes from the most severe level to the moderate level, and is set to 0% for the mild and normal levels. Figure 15 shows the screen of the monitor 40 in Case B. In Case C of Table 1 above, only the most severe level has a transmittance of 50%, and the other levels are set to a transmittance of 0%.

[0085] If there is an area set to a transmittance of 100%, only the endoscopic image 40A is displayed in that area, and it is therefore not clear which part of the image displays the identification image 40B. For this reason, it is acceptable to display it as in the following cases 1 to 3.

[0086] (Case 1) As shown in Figure 14, when an identification image 40B having a 100% transmittance area is superimposed only on the center portion of an endoscopic image 40A, the boundary of the identification image 40B is displayed with a solid or dashed line. (Case 2) Although not shown, when only the most severe (red) area has a transmittance of 50% and the other levels have a transmittance of 100%, the boundary between the most severe area and the other areas is displayed with a solid or dashed line. (Case 3) When multiple levels are set to 100% transmittance, such as when the transmittance is set to 100% for areas from moderate to normal, the boundaries between the multiple level areas are not visible on the screen. Although not shown, the boundaries between the multiple level areas are displayed with a solid or dashed line. For example, by displaying the boundaries between the moderate and mild areas and the mild and normal areas with a solid line, the boundaries between the areas can be seen even when multiple levels have a transmittance of 100%.

[0087] 13, the screen of the monitor 40 in Fig. 16 displays an endoscopic image 40A and an identification image 40B, as well as an identification image 40BP of a range similar to the identification image 40B from a past examination of the subject 90. However, unlike Fig. 13, in the identification image 40B, of the five color regions, only the red color representing the most severe level is displayed in color, and the regions from normal levels to severe levels are displayed in white.

[0088] The most severe level is the level with the largest number of pixels, in other words, the largest area, in the past identification image 40BP. The level at which the identification image 40B is displayed in color is not limited to the most severe level, and can be set as appropriate.

[0089] As described above, in another embodiment of the method for operating an endoscopic system, the imaging unit 15 of the endoscope 10 captures an image of an object 91 inside the body of a subject 90 and outputs an image signal, the processor 30 performs image processing on the image signal to generate an object image, calculates an index for each pixel by normalizing the sum of the red pixel value and the green pixel value of each of a plurality of pixels in at least a partial area of ​​the object image by twice the blue pixel value, stores a plurality of thresholds for classifying a plurality of areas of the object into one of three or more symptom levels and discrimination colors corresponding to each of the plurality of symptom levels, discriminates the symptom level of each pixel using the plurality of thresholds based on the index, obtains the discrimination color corresponding to the symptom level of each pixel, generates a discrimination image using the discrimination colors of each of the plurality of pixels, and the monitor 40 displays the discrimination image.

[0090] A program according to another embodiment causes a computer to execute the above process.

[0091] In another embodiment, a non-transitory computer-readable storage medium stores a program that causes a computer to perform the above processes.

[0092] The ranges of the numerical values ​​described above, for example, the wavelength, are not limited to the ranges described above and can be increased or decreased as appropriate. Furthermore, the endoscope 10 may have a rigid insertion section 11. The present invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the present invention.

[0093] DESCRIPTION OF SYMBOLS 1 Endoscope device 3 Insertion section 9 Endoscope 10 Endoscope 11 Insertion section 11A Tip section 11B Bending section 11C Flexible tube 12 Operation section 12A Button 13 Universal cord 14 Connector 15 Imaging unit 16 Lighting unit 20 Light source device 22 Light source control section (light source control circuit) 23 Light source 23B B element 23G G element 23R R element 24 Multiplexer 30 Processor 31 Image processing section (image processing circuit) 32 Calculation section (calculation circuit) 33 Identification section (identification circuit) 34 Distinguished color acquisition section (distinguished color acquisition circuit) 35 Image generation section (image generation circuit) 36 Setting section 40 Monitor 40A Endoscopic image 40B, 40BP... Identification image 40C... Identification color list display 40D... Average value 50... Memory 90... Subject 91... Subject

Claims

1. An endoscopic device comprising: an endoscope having an imaging unit that images at least any subject inside a subject's body and outputs an image signal; an image processing unit that performs image processing on the image signal to generate an image of the subject; a calculation unit that calculates an index for each of a plurality of pixels in at least a portion of the image of the subject by normalizing the sum of the red pixel value and the green pixel value of each of the pixels in at least a portion of the image of the subject by twice the blue pixel value; a memory that stores a plurality of thresholds for classifying the plurality of regions of the subject into one of three or more symptom levels and discrimination colors corresponding to each of the plurality of symptom levels; a discrimination unit that uses the plurality of thresholds to discriminate the symptom level of each of the pixels based on the index; a discrimination color acquisition unit that acquires the discrimination color corresponding to the symptom level of each of the pixels; an image generation unit that generates a discrimination image using the discrimination color of each of the plurality of pixels; and a monitor that displays the discrimination image.

2. An endoscope apparatus according to claim 1, characterized in that the multiple symptom levels are normal / mild / moderate / severe / very severe.

3. An endoscope apparatus according to claim 1, wherein each of the plurality of threshold values ​​is set within a predetermined range.

4. The endoscope apparatus according to claim 1, wherein the differences between the multiple threshold values ​​are approximately the same.

5. The endoscopic device described in claim 2, characterized in that a first threshold difference between a first threshold for discriminating between the normal condition and the mild condition and a second threshold for discriminating between the mild condition and the moderate condition is greater than a second threshold difference between the second threshold and a third threshold for discriminating between the moderate condition and the severe condition, and the second threshold difference is greater than a third threshold difference between the third threshold and a fourth threshold for discriminating between the severe condition and the most severe condition.

6. The endoscopic device described in claim 2, characterized in that a first threshold difference between a first threshold for discriminating between the normal condition and the mild condition and a second threshold for discriminating between the mild condition and the moderate condition is smaller than a second threshold difference between the second threshold and a third threshold for discriminating between the moderate condition and the severe condition, and the second threshold difference is smaller than a third threshold difference between the third threshold and a fourth threshold for discriminating between the severe condition and the most severe condition.

7. The endoscope apparatus according to claim 2, wherein the memory stores a plurality of threshold sets including the plurality of thresholds corresponding to a plurality of subjects, respectively.

8. An endoscopic device as described in claim 7, characterized in that the variation in the thresholds in the multiple threshold sets that distinguish between the severe condition and the most severe condition is smaller than the variation in the thresholds that distinguish between the normal condition and the mild condition.

9. The endoscope apparatus according to claim 8, wherein the image processing section performs white balance adjustment using white as the color balance calibration.

10. An endoscope apparatus according to claim 7, wherein the variation in the threshold value is controlled by the colors used in color balance calibration.

11. The endoscope device according to claim 10, wherein the image processing unit performs adjustment using intermediate colors between the colors of the normal area and the most severe area as color balance calibration.

12. The endoscope apparatus according to claim 1, wherein the calculation unit calculates the index using one of a plurality of calculation formulas corresponding to each of a plurality of subjects.

13. The endoscope device described in claim 1, characterized in that the memory stores an error color as the identification color for a first error pixel in which at least one of the red pixel value, the green pixel value, and the blue pixel value is below a predetermined lower limit pixel value or above a predetermined upper limit pixel value, and for a second error pixel in which the index is below a predetermined lower limit threshold value or above a predetermined upper limit threshold value, and the image generation unit generates the identification image using the error color for the first error pixel and the second error pixel.

14. The endoscope device according to claim 13, characterized in that a warning is output when the ratio of the number of the first error pixels, the number of the second error pixels, or the sum of the number of the first error pixels and the number of the second error pixels to the total number of pixels is greater than a predetermined ratio.

15. An endoscope apparatus according to claim 1, wherein a past image, which is an identification image from a past examination of the subject, is displayed on the monitor together with the identification image.

16. An endoscopic device as described in claim 15, characterized in that an identification color is selected from the respective identification colors of the plurality of pixels for the past image, and only the pixels of the selected identification color are displayed as an identification image, and the other pixels are displayed in white or an endoscopic image.

17. An endoscope device as described in claim 1, characterized in that at least one discrimination color is selected from the discrimination colors of each of the plurality of pixels, and only the pixels of the selected discrimination color are displayed in color, and the other pixels are displayed in white.

18. The endoscope apparatus according to claim 1, wherein the identification image is made semi-transparent and is displayed on the monitor superimposed on the subject image.

19. An endoscope apparatus according to claim 17, characterized in that the identification image is made semi-transparent with a different transmittance for each of the plurality of identification colors.

20. The endoscope apparatus according to claim 17, wherein only a discrimination color selected from said plurality of discrimination colors is made semi-transparent.

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