JP6196599B2 - Endoscope processor device and method of operating endoscope processor device - Google Patents

Description

  The present invention relates to an endoscopic processor device that determines a defective image by using a degree of unsharpness obtained from a blood vessel in an image and a blood vessel index value, and an operating method of the endoscopic processor device.

  In recent medical treatments, diagnosis using an endoscope system including an endoscope light source device (hereinafter referred to as a light source device), an electronic endoscope (hereinafter referred to as an endoscope), and a processor device is widely performed. Yes. The light source device generates illumination light for illuminating the observation target. The endoscope includes an image sensor and images an observation target illuminated with illumination light to generate an image signal. The processor device performs image processing on the image signal transmitted from the endoscope, and generates an image to be displayed on the monitor.

  In the diagnosis using the endoscope system, first, screening is performed by non-magnifying observation in order to pick up a possible lesion site that may be a lesion. When a lesion-possible site is picked up, a detailed diagnosis is performed by enlarging the lesion-possible site by approaching the distal end of the endoscope to the lesion-possible site or by optical zoom. During magnified observation, there may be a case where a defective image in which blood vessels or the like important for diagnosis are unclear is easily obtained due to blurring or blurring of the image due to the operation of the endoscope or the pulsation of the observation target. Since a defective image may cause a doctor's misdiagnosis, the processor device determines that the acquired image is a defective image, and then performs image processing such as correcting the image (the following patent document). 1).

Japanese Patent No. 5562808

  In the endoscope field in recent years, there is a movement to further objectively diagnose a lesioned part by digitizing information on blood vessels such as a blood vessel shape and a blood vessel density as a blood vessel index value. In this way, when information about blood vessels is digitized, it is assumed that blood vessels are clearly shown in the image.

  However, as described above, during the diagnosis of the endoscope, the image is blurred or blurred due to the operation of the endoscope or the pulsation of the observation target, and it is difficult to clearly display the blood vessels in the image. There is a case. In particular, when observing in a state where the distal end portion of the endoscope is stationary as in magnified observation, even a slight movement by the endoscope or the observation target affects the visibility of the blood vessels in the image. It becomes even more difficult to project clearly.

  On the other hand, it is conceivable that the blood vessel index value is obtained after the blood vessel is clarified by correcting the blur and the blur by the method according to Patent Document 1. Here, in Patent Document 1, a blood vessel intersection is extracted from an image, and blur correction is performed based on the amount of motion obtained from the blood vessel intersection. However, it is difficult to accurately determine the amount of movement when the image has already been blurred or out of focus. In this case, the blur cannot be corrected completely, and as a result, it is difficult to accurately calculate the blood vessel index value.

  The present invention relates to an endoscopic processor device and an endoscopic processor device capable of accurately displaying blood vessel information even when blurring or out of focus occurs in an image during observation with an endoscope. It aims at providing the operating method of.

To achieve the above object, an endoscope processor device according to the present invention includes an image signal acquisition unit that acquires an image signal obtained by imaging an observation target with an endoscope at different timings, and an image signal. A blood vessel extraction unit that extracts a blood vessel and generates a blood vessel image signal, a blood vessel index value calculation unit that calculates a blood vessel index value from the extracted blood vessel, and an image based on the image signal from the blood vessel index value comprising a determining unit which determines whether a defective image, a process based on the result of the determination, a determination postprocessing section which performs for at least one of the blood vessel image signal and the blood vessel index value, the determination unit Is determined to be a defective image when the blood vessel index value changes by a certain value or more .

In the operating method of the processor device for an endoscope of the present invention, the image signal acquisition unit acquires the image signal obtained by imaging the observation target with the endoscope at different timings, and the blood vessel extraction unit includes: Extracting a blood vessel from the image signal and generating a blood vessel image signal; a blood vessel index value calculating unit calculating a blood vessel index value from the extracted blood vessel; and a determining unit calculating the image from the blood vessel index value. A step of determining whether the image based on the signal is a defective image with respect to sharpness, and a post-determination processing unit that performs processing based on the determination result for at least one of the blood vessel image signal and the blood vessel index value comprising the steps performed by the determination unit, when the blood vessel index value has changed more than a certain value, it is determined to be defective image.

  The blood vessel index value calculation unit preferably calculates the blood vessel index value from at least one of the width of the blood vessel, the density of the blood vessel, the number of blood vessels, the traveling direction of the blood vessel, the shape of the blood vessel, and the sharpness of the blood vessel.

  The image signal acquisition unit acquires the image signal at the first timing, acquires the image signal at the second timing before the first timing, and the blood vessel extraction unit acquires the image signal acquired at the first timing. A blood vessel is extracted from the first timing to generate a blood vessel image signal at the first timing, a blood vessel is extracted from the image signal acquired at the second timing to generate a second timing blood vessel image signal, and a blood vessel index value calculation unit Calculates the blood vessel index value at the first timing based on the blood vessel extracted from the image signal acquired at the first timing, and the second based on the blood vessel extracted from the image signal acquired at the second timing. And the determination unit determines that the image is a defective image when the blood vessel index value at the first timing changes by a predetermined value or more with respect to the blood vessel index value at the second timing. But Masui.

  It is preferable to include an image generation unit that generates an image based on the determination result.

  The post-determination processing unit preferably includes an image correction unit that performs image correction processing on an image based on the image signal when it is determined that the image is a defective image. The image signal acquisition unit acquires the image signal at the first timing, acquires the image signal at the second timing before the first timing, and the image correction unit performs the image correction processing at the second timing. It is preferable to carry out based on the image signal. A movement amount calculation unit that calculates a movement amount between the image signal at the first timing and the image signal at the second timing, and the positions of the blood vessel at the first timing and the blood vessel at the second timing from the movement amount The image correction unit preferably performs image correction processing based on the movement amount.

  When it is determined that the image is a defective image, the image generation unit preferably generates an image in which the blood vessel at the second timing overlaps the image at the first timing. The blood vessel index value calculation unit calculates the blood vessel index value at the first timing based on the blood vessel extracted from the image signal acquired at the first timing, and the blood vessel extracted from the image signal acquired at the second timing. And when the image generation unit determines that the image is a defective image, the image generation unit converts the information based on the blood vessel index value at the second timing into the image at the first timing. It is preferable to generate an overlapped image. The image generation unit preferably replaces the blood vessel index value at the first timing with the blood vessel index value at the second timing.

  The post-determination processing unit preferably includes an index value correction unit that performs an index value correction process on the blood vessel index value when it is determined that the image is a defective image. The image signal acquisition unit acquires the image signal at the first timing, acquires the image signal at the second timing before the first timing, and the index value correction unit performs the index value correction processing in the first timing. It is preferable to carry out based on the image signal at the second timing before the timing. A movement amount calculation unit that calculates a movement amount between the image signal at the first timing and the image signal at the second timing has an index value correction unit that performs the index value correction process based on the movement amount. It is preferable. It is preferable to have a blood vessel position correction unit that adjusts the blood vessel at the first timing to the position of the blood vessel at the second timing based on the movement amount.

  When it is determined that the image is a defective image, the image generation unit preferably generates an image in which the blood vessel at the second timing overlaps the image at the first timing. When the blood vessel index value calculation unit calculates the blood vessel index value at the second timing based on the blood vessel extracted from the image signal acquired at the second timing, and the image generation unit determines that the image is a defective image It is preferable to generate an image in which information based on the blood vessel index value at the second timing is overlapped with the image at the first timing.

  When it is determined that the image is a defective image, the image generation unit preferably hides information based on blood vessels and information based on blood vessel index values. When the image generation unit determines that the image is a defective image, it is preferable to display a warning for the image based on the image signal.

  According to the present invention, a processor device for an endoscope that can accurately display information on blood vessels by accurately determining a defective image using a blood vessel index value obtained from the blood vessels in the image. It is possible to provide a method of operating the processor device of the present invention.

It is an external view of an endoscope system. It is a block diagram which shows the function of an endoscope system. It is a graph which shows the spectrum of purple light, blue light, green light, and red light. It is a graph which shows the spectral characteristic of a color filter. It is a block diagram which shows the function of a special image process part. It is a block diagram which shows the function of a blood vessel extraction part. It is explanatory drawing which shows a mode that the light from the blood vessel is diffused. It is a graph showing distribution of the received light quantity in an image sensor. It is explanatory drawing which shows the production | generation method of the blood vessel position signal. It is explanatory drawing which shows the production | generation method of the blood vessel width signal. It is a schematic diagram of a blood vessel image signal. It is a flowchart which shows the determination method of a defective image. It is a block diagram which shows the function of an image correction part. It is a schematic diagram of a blood vessel emphasis image signal. It is a schematic diagram of a special image signal that has been pseudo-colored. It is a schematic diagram of a special image signal with a region of interest. It is a schematic diagram of a special image signal to which information related to warning display is given. It is a flowchart of a 1st embodiment. It is a block diagram which shows the function of the special image process part of 2nd Embodiment. It is a block diagram which shows the function of the index value correction | amendment part of 2nd Embodiment. It is a block diagram which shows the function of the endoscope system of 3rd Embodiment. It is a graph which shows the emission spectrum of white light. It is a graph which shows the emission spectrum of special light. It is a block diagram which shows the function of the endoscope system of 4th Embodiment. It is a top view which shows a rotation filter.

[First Embodiment]
As shown in FIG. 1, the endoscope system 10 includes an endoscope 12, a light source device 14, a processor device 16, a monitor 18, and a console 19. The endoscope 12 is optically connected to the light source device 14 and electrically connected to the processor device 16. The endoscope 12 includes an insertion portion 12a to be inserted into the body to be observed, an operation portion 12b provided at the proximal end portion of the insertion portion 12a, a bending portion 12c provided at the distal end side of the insertion portion 12a, and a distal end. Part 12d. By operating the angle knob 12e of the operation unit 12b, the bending unit 12c performs a bending operation. By this bending operation, the distal end portion 12d is directed in a desired direction.

  In addition to the angle knob 12e, the operation unit 12b is provided with a mode switch SW (mode switch) 12f, a still image acquisition instruction unit 12g, and a zoom operation unit 12h. The mode switching SW 12f is used for an observation mode switching operation. The endoscope system 10 has a normal observation mode and a special observation mode as observation modes. In the normal observation mode, an image having a natural color (hereinafter referred to as a normal image) obtained by imaging an observation target using white light as illumination light is displayed on the monitor 18. In the special observation mode, an image obtained by using light of a specific wavelength band as illumination light (hereinafter referred to as a special image) is displayed on the monitor 18. The still image acquisition instruction unit 12g is used to cause the endoscope system 10 to acquire a still image and to store the acquired still image in a storage (not shown). The zoom operation unit 12h is used to instruct a change between magnified observation in which an observation target is magnified and non-magnified observation in which magnified observation is not performed.

  The processor device 16 is electrically connected to the monitor 18 and the console 19. The monitor 18 outputs and displays an image to be observed, information attached to the image to be observed, and the like. The console 19 functions as a user interface that receives input operations such as function settings. The processor device 16 may be connected to an external recording unit (not shown) for recording images, image information, and the like.

  As shown in FIG. 2, the light source device 14 includes a light source 20 and a light source control unit 22 that controls the light source 20. The light source 20 includes, for example, a plurality of semiconductor light sources, and these are turned on or off, and when they are turned on, the amount of light emitted from each semiconductor light source is controlled to generate illumination light that irradiates the observation target. In the present embodiment, the light source 20 includes a V-LED (Violet Light Emitting Diode) 20a, a B-LED (Blue Light Emitting Diode) 20b, a G-LED (Green Light Emitting Diode) 20c, and an R-LED (Red Light Emitting Diode). Diode) 20d has four-color LEDs.

  As shown in FIG. 3, the V-LED 20a is a violet semiconductor light source that emits violet light V having a center wavelength of 405 nm and a wavelength band of 380 nm to 420 nm. The B-LED 20b is a blue semiconductor light source that emits blue light B having a center wavelength of 460 nm and a wavelength band of 420 nm to 500 nm. The G-LED 20c is a green semiconductor light source that emits green light G having a wavelength band ranging from 480 nm to 600 nm. The R-LED 20d is a red semiconductor light source that emits red light R with a center wavelength of 620 nm to 630 nm and a wavelength band of 600 nm to 650 nm. The center wavelengths of the V-LED 20a and the B-LED 20b have a width of about ± 5 nm to ± 10 nm.

  The lighting and extinguishing of each of these LEDs 20a to 20d, the light emission amount at the time of lighting, and the like can be controlled by the light source control unit 22 by inputting an independent control signal. In this embodiment, the light source control unit 22 turns on all the V-LEDs 20a, B-LEDs 20b, G-LEDs 20c, and R-LEDs 20d in both the normal observation mode and the special observation mode. For this reason, white light including purple light V, blue light B, green light G, and red light R is used as illumination light in the normal observation mode and special observation mode.

  The light of each color emitted from each LED 20a to 20d is incident on a light guide 41 inserted into the insertion portion 12a through an optical path coupling portion 23 formed by a mirror, a lens, or the like. The light guide 41 is built in the endoscope 12 and the universal cord (a cord connecting the endoscope 12, the light source device 14, and the processor device 16). The light guide 41 propagates the illumination light generated by the light source 20 to the distal end portion 12 d of the endoscope 12.

  The distal end portion 12d of the endoscope 12 is provided with an illumination optical system 30a and an imaging optical system 30b. The illumination optical system 30 a has an illumination lens 45, and the illumination light propagated by the light guide 41 is irradiated to the observation object via the illumination lens 45. The imaging optical system 30 b includes an objective lens 46, a zoom lens 47, and an imaging sensor 48. Various types of light such as reflected light, scattered light, and fluorescence from the observation target due to the irradiation of the illumination light enter the image sensor 48 via the objective lens 46 and the zoom lens 47. As a result, an image to be observed is formed on the image sensor 48. The zoom lens 47 is freely moved between the tele end and the wide end by operating the zoom operation unit 12h, and enlarges or reduces the reflected image of the observation object formed on the image sensor 48.

  The imaging sensor 48 is a color imaging sensor that images an observation target irradiated with illumination light. Each pixel of the image sensor 48 is provided with any of an R (red) color filter, a G (green) color filter, and a B (blue) color filter shown in FIG. Therefore, the imaging sensor 48 receives purple to blue light at the B pixel (blue pixel) provided with the B color filter, and receives green light at the G pixel (green pixel) provided with the G color filter. The red light is received by the R pixel (red pixel) provided with the R color filter. Then, RGB color image signals are output from each color pixel.

  As the image sensor 48, a CCD (Charge Coupled Device) image sensor or a CMOS (Complementary Metal-Oxide Semiconductor) image sensor can be used. Further, instead of the primary color imaging sensor 48, a complementary color imaging sensor including complementary color filters of C (cyan), M (magenta), Y (yellow), and G (green) may be used. When the complementary color image sensor is used, CMYG four-color image signals are output. By converting the CMYG four-color image signals into RGB three-color image signals by complementary color-primary color conversion, An RGB image signal similar to that of the image sensor 48 can be obtained. Further, instead of the imaging sensor 48, a monochrome sensor without a color filter may be used.

  The CDS / AGC circuit 51 performs correlated double sampling (CDS) and automatic gain control (AGC) on the analog image signal obtained from the image sensor 48. The image signal that has passed through the CDS / AGC circuit 51 is converted into a digital image signal by an A / D (Analog to Digital) converter 52. The digital image signal after A / D conversion is input to the processor device 16.

  The processor device 16 includes an image signal acquisition unit 54, a DSP (Digital Signal Processor) 56, a noise removal unit 58, an image processing switching unit 61, a normal image processing unit 66, a special image processing unit 67, and a video signal. And a generating unit 68. The image signal acquisition unit 54 acquires a digital image signal from the imaging sensor 48 via the CDS / AGC circuit 51 and the A / D converter 52.

  The DSP 56 performs various signal processing such as defect correction processing, offset processing, gain correction processing, linear matrix processing, gamma conversion processing, and demosaicing processing on the acquired image signal. In the defect correction process, the signal of the defective pixel of the image sensor 48 is corrected. In the offset process, the dark current component is removed from the image signal subjected to the defect correction process, and an accurate zero level is set. In the gain correction process, the signal level is adjusted by multiplying the image signal after the offset process by a specific gain.

  The image signal after gain correction processing is subjected to linear matrix processing for improving color reproducibility. After that, brightness and saturation are adjusted by gamma conversion processing. The image signal after the gamma conversion processing is subjected to demosaic processing (also referred to as isotropic processing or synchronization processing), and a signal of a color that is insufficient at each pixel is generated by interpolation. By this demosaic processing, all the pixels have RGB signals. The noise removal unit 58 removes noise by performing noise removal processing (for example, using a moving average method, a median filter method, or the like) on the image signal that has been demosaiced by the DSP 56. The image signal from which the noise has been removed is transmitted to the image processing switching unit 61. When the normal observation mode is set by the operation of the mode switch SW12f, the image processing switching unit 61 transmits the RGB color image signals to the normal image processing unit 66, and when the special observation mode is set, The RGB image signal is transmitted to the special image processing unit 67.

  The normal image processing unit 66 operates when the normal observation mode is set, and performs a color conversion process, a color enhancement process, and a structure enhancement process on the RGB image signal to generate a normal image signal. In the color conversion processing, color conversion processing is performed on the RGB image signal by 3 × 3 matrix processing, gradation conversion processing, three-dimensional LUT (look-up table) processing, and the like. The color enhancement process is performed on the image signal that has been subjected to the color conversion process. The structure enhancement process is a process for enhancing a structure to be observed such as a surface blood vessel or a pit pattern, and is performed on the image signal after the color enhancement process. As described above, a color image using a normal image signal that has been subjected to various types of image processing up to the structure enhancement processing is a normal image.

  The special image processing unit 67 is an image processing unit that operates when the special observation mode is set, and generates a special image based on the RGB image signal. As shown in FIG. 5, the special image processing unit 67 includes a blood vessel extraction unit 70, a blood vessel index value calculation unit 72, a determination unit 74, an image correction unit 76 (post-determination processing unit), and a special image generation unit 78. And comprising. In the following description, the function of the special image processing unit 67 will be described using an image signal acquired at the first timing (hereinafter also simply referred to as an image signal).

  The blood vessel extraction unit 70 generates a blood vessel image signal obtained by extracting a blood vessel to be observed from the image signal. As illustrated in FIG. 6, the blood vessel extraction unit 70 includes a blood vessel position signal generation unit 80, a blood vessel width signal generation unit 81, and a blood vessel image signal generation unit 82.

  The blood vessel position signal generation unit 80 generates a blood vessel position signal representing the position of the blood vessel to be observed using the image signal. Specifically, the blood vessel position signal generation unit 80 extracts a blood vessel to be observed from the input image signal by the black hat process, and further binarizes the image signal after the black hat process, thereby obtaining a blood vessel. A blood vessel position signal having a specific positive value (for example, “1”) and a pixel value of the other pixels being zero is generated. The blood vessel position signal is input to the blood vessel image signal generation unit 82.

  The black hat process is a morphological process (also referred to as a morphological process) that extracts a pixel having a smaller pixel value than a neighboring pixel while removing noise, and the original image signal is obtained from the image signal subjected to the closing process. This is a subtraction process. The closing process is a process of performing an erosion process for contracting a bright area after performing a dilation process for expanding a bright area. The image signal obtained from the image sensor 48 has a pixel value proportional to the amount of light incident from the observation target. The blood vessel contains a lot of hemoglobin that easily absorbs illumination light compared to the mucous membrane. Therefore, since the blood vessel has a small pixel value in the image signal, the blood vessel can be extracted by the black hat process. In addition, since the original image signal is subtracted from the image signal subjected to the closing process, the pixel value of the pixel representing the blood vessel is a large value in the image signal after the black hat process.

  If the size, shape, etc. of the structural elements (also called kernels) used for black hat processing are set appropriately, only the blood vessels can be accurately extracted by binarizing the image signal after black hat processing. Can do. For this reason, the blood vessel position signal generated by the blood vessel position signal generation unit 80 accurately represents the position of the blood vessel. However, the blood vessel represented by the blood vessel position signal has an inaccurate width (thickness on the image) and includes an error. This is because the light 85 from the blood vessel 84 is diffused by scattering or the like while propagating through the observation object 86, as shown in FIG. As shown in FIG. 8, when the light 85 from the blood vessel 84 is diffused by scattering or the like, and the distribution of the amount of light received by the imaging sensor 48 spreads in a Gaussian function type, as shown in FIG. When the processed image signal 88 is binarized to generate the blood vessel position signal 89, the width of the blood vessel 84 in the blood vessel position signal 89 changes depending on the setting value of the threshold Th for binarization. Therefore, the blood vessel position signal 89 is accurate in the position of the blood vessel 84, but there is an error in the width of the blood vessel 84. The accurate position of the blood vessel 84 means that there is no noise and only the blood vessel 84 is extracted.

  Note that the special image processing unit 67 receives RGB color image signals from the image processing switching unit 61, and the blood vessel position signal generation unit 80 uses the B image signal corresponding to at least the blue wavelength band among these to output the blood vessel position signal. Is generated. This is because of the RGB image signals, the B image signal is the image signal with the highest contrast of blood vessels in the vicinity of the mucosal surface layer, which is highly important for the diagnosis of lesions and the like. When extracting a blood vessel at a relatively deep position below the mucosa by setting, a G image signal corresponding to the green wavelength band may be used.

  The blood vessel width signal generation unit 81 generates a blood vessel width signal representing the width of the blood vessel to be observed using the image signal, and inputs it to the blood vessel image signal generation unit 82. Specifically, the blood vessel width signal generation unit 81 extracts a blood vessel to be observed by black hat processing, and further performs LOG filter (Laplacian Of Gaussian Filter) processing on the image signal after the black hat processing. Then, a binary blood vessel width signal is generated using the zero point of the image signal after the LOG filter processing. The LOG filter process is a composite filter process of a Gaussian filter process and a Laplacian filter process, and is a filter process for smoothing an image signal by Gaussian filter process to remove noise and then performing second order differentiation by Laplacian filter process. That is, the blood vessel width signal generation unit 81 generates a blood vessel width signal using the zero point of the image signal after the second order differentiation.

  For example, when the LOG filter process is performed on the image signal 88 after the black hat process shown in FIG. 10A, the zero point of the image signal 90 after the LOG filter process is a blood vessel as shown in FIG. The 84 edges are represented almost exactly. Therefore, as shown in FIG. 10C, the blood vessel width signal generation unit 81 extracts the blood vessel width signal 91 by extracting a region between zero points and a negative pixel value of the image signal 90 after the LOG filter processing. Generate. In the blood vessel width signal 91, a region representing a blood vessel is represented by a “white” pixel having a specific positive value (for example, “1”), and a region other than the blood vessel is represented by a “black” pixel having a pixel value of zero. As can be seen from the above generation method, the width of the blood vessel 84 is accurate in the blood vessel width signal 91. However, since Laplacian filter processing for differentiating is used, even a very small amount of noise is emphasized, and those other than the blood vessel 84 are also extracted as noise. Therefore, the blood vessel width signal 91 accurately represents the width of the blood vessel 84, but also includes noise other than the blood vessel 84.

  The blood vessel image signal generation unit 82 generates a blood vessel image signal representing the blood vessel to be observed using the blood vessel position signal and the blood vessel width signal. Specifically, a blood vessel image signal is generated by a logical product (“AND”) of the blood vessel position signal and the blood vessel width signal. When the logical product of the blood vessel position signal and the blood vessel width signal is taken, only the pixels having a specific positive value in common with the blood vessel position signal and the blood vessel width signal are extracted, and only one of the blood vessel position signal and the blood vessel width signal is extracted. A pixel having a specific positive value becomes a pixel having a pixel value of zero. Accordingly, the blood vessel represented by the blood vessel image signal is at a position represented by the blood vessel position signal and has a width represented by the blood vessel width signal. Further, the blood vessel image signal contains almost no noise components other than blood vessels. That is, as shown in FIG. 11, the blood vessel image signal 92 corresponds to an image signal obtained by extracting only blood vessels from the original image signal with accurate position and width. The blood vessel image signal 92 has no noise appearing in the blood vessel width signal, and the position of the superficial blood vessel 93 near the surface of the mucous membrane and the extreme superficial blood vessel 94 distributed at a depth very close to the surface of the mucosa among the superficial blood vessels 93 are correct. And the widths of the superficial blood vessel 93 and the extreme superficial blood vessel 94 are also correct. The reason why the superficial blood vessel 93 and the polar superficial blood vessel 94 can be extracted is that illumination light including purple light V is used.

  Note that the blood vessel width signal generation unit 81 generates a blood vessel width signal using a B image signal corresponding to at least the blue wavelength band among the RGB image signals in the same manner as the blood vessel position signal generation unit 80. . Depending on the setting, a G image signal may be used.

  As shown in FIG. 5, the blood vessel index value calculation unit 72 calculates a blood vessel index value obtained by indexing the blood vessel represented by the blood vessel image signal 92. The blood vessel index value includes the width of the blood vessel represented by the blood vessel image signal 92, the density of the blood vessel, the number of blood vessels, the running direction of the blood vessel, the shape of the blood vessel, the sharpness of the blood vessel, and the like. For example, when calculating the blood vessel density (ratio of blood vessels in a unit area) as a blood vessel index value, the blood vessel image signal 92 has a specific size (unit area) centered on a pixel for calculating the blood vessel density. A region is cut out, and the ratio of the superficial blood vessel 93 and the polar superficial blood vessel 94 occupying all the pixels in the region is calculated. By performing this operation for all the pixels of the blood vessel image signal 92, the blood vessel density of each pixel of the blood vessel image signal 92 is calculated. The calculated blood vessel index value is transmitted to the determination unit 74.

  Note that the endoscope system 10 images an observation target at a plurality of timings, and the blood vessel index value calculation unit 72 calculates a blood vessel index value at each timing. The blood vessel index value changes at the timing before and after this when the image is shaken or blurred due to the operation of the endoscope or the pulsation of the observation target. On the other hand, when there is no blur or out of focus, the blood vessel index value becomes a constant value at the timing before and after. For this reason, the blood vessel index value can be used to determine whether or not blurring or defocusing has occurred in the image.

  The determination unit 74 uses the blood vessel index value received from the blood vessel index value calculation unit 72 to determine whether the image corresponding to the blood vessel image signal 92 obtained at the first timing is a defective image with respect to the sharpness. Make a decision. The determination result is transmitted to the image correction unit 76. The sharpness is a degree indicating how clearly the blood vessels in the image appear, and the greater the sharpness, the smaller the blurring and blurring of the image and the clearer the blood vessels are expressed. A defective image is an image with low sharpness and unclear thin blood vessels. The determination unit 74 includes a blood vessel index value memory (not shown) for storing the blood vessel index value at each timing, and stores the blood vessel index value in the blood vessel index value memory every time the blood vessel index value is received. It has become.

  As illustrated in FIG. 12, the determination unit 74 compares the blood vessel index value at the first timing with the blood vessel index value at the second timing before the first timing, and the blood vessel at the second timing. When the blood vessel index value at the first timing changes by a certain value or more with respect to the index value, it is determined that the image at the first timing is a defective image.

  When the blood vessel index value at the first timing is less than a certain value with respect to the blood vessel index value at the second timing, frequency analysis is performed on the blood vessel image signal 92 at the first timing. In the frequency analysis, a high frequency component corresponding to a thin blood vessel and a low frequency component corresponding to a thick blood vessel are obtained. Then, the high-frequency component included in the blood vessel image signal 92 at the first timing is less than the high-frequency component included in the blood vessel image signal at the second timing, and the low-frequency component included in the blood vessel image signal 92 at the first timing. Is greater than the low-frequency component included in the blood vessel image signal at the second timing, the determination unit 74 determines that the image at the first timing is a defective image.

  The high frequency component included in the first timing blood vessel image signal 92 is greater than or equal to the high frequency component included in the second timing blood vessel image signal, and the low frequency component included in the first timing blood vessel image signal 92 is the first timing. If it is equal to or lower than the low-frequency component included in the blood vessel image signal at the timing 2, the determination unit 74 determines that the image at the first timing is not a defective image.

  As a result of the determination by the determination unit 74, the image correction unit 76 performs image correction processing on the blood vessel image signal at the first timing when it is determined as a defective image. As shown in FIG. 13, the image correction unit 76 includes a signal switching unit 96, a movement amount calculation unit 97, and an alignment unit 98.

  The signal switching unit 96 receives the blood vessel image signal and the determination result from the determination unit 74, and transmits the blood vessel image signal to the movement amount calculation unit 97 when the determination result indicates that the image is a defective image. When it is determined that the image is not an image, the transmission destination is switched so that the blood vessel image signal is transmitted to the special image generation unit 78.

  The movement amount calculation unit 97 receives the blood vessel image signal from the signal switching unit 96 and calculates the movement amount between the blood vessel image signal at the first timing and the blood vessel image signal at the second timing. Specifically, by performing a comparison calculation of the image signals for the blood vessels represented in the blood vessel image signal at the first timing and the blood vessels represented in the blood vessel image signal at the second timing, X The movement amount in the direction and the movement amount in the Y direction are calculated.

  The alignment unit 98 uses the movement amount calculated by the movement amount calculation unit 97 and the blood vessel represented in the blood vessel image signal at the first timing and the blood vessel represented in the blood vessel image signal at the second timing. Align between the two. When performing alignment, the blood vessel image signal at the first timing is moved in a direction to cancel the positional shift by the amount of movement. Thereby, the position of the blood vessel represented in the blood vessel image signal at the first timing is matched with the position of the blood vessel represented in the blood vessel image signal at the second timing. The blood vessel image signal after alignment is transmitted to the special image generation unit 78.

  The special image generation unit 78 generates a special image signal using the image signal, the blood vessel image signal, and the blood vessel index value acquired at the first timing. An image using the special image signal is a special image. Specifically, the special image generation unit 78 performs a color conversion process, a color enhancement process, and a structure enhancement process on the image signal acquired at the first timing, and generates a base image signal. Next, a blood vessel emphasis image signal is generated by overlapping the blood vessel image signal with respect to the base image signal. As shown in FIG. 14, in the image based on the blood vessel emphasized image signal 100, the shape 101 such as the undulation to be observed can be observed, and the superficial blood vessel 93 and the extreme superficial blood vessel 94 are emphasized.

  The special image generation unit 78 generates a special image signal by performing overlap processing on the blood vessel emphasized image signal 100 with information based on the blood vessel index value. Specifically, the pseudo-color special image signal 102 is obtained by subjecting the blood vessel emphasized image signal 100 to color processing according to the blood vessel index value. For example, in the special image signal 102 shown in FIG. 15, the region 103 having a blood vessel index value equal to or greater than a certain value is displayed in a pseudo color, and the pseudo color region 103 is displayed in a different color according to the blood vessel index value. ing. Further, a region of interest (ROI (Region of Interest)) 104 is set for the blood vessel enhanced image signal 100 based on the blood vessel index value, thereby obtaining a special image signal 105 with a region of interest. For example, in the special image signal 105 shown in FIG. 16, a frame indicating the region of interest 104 is displayed in a region where the blood vessel index value is a certain value or more. Note that the overlap processing based on the blood vessel index value may be performed by replacing the blood vessel index value at the first timing with the blood vessel index value at the second timing. This is particularly effective when a defective image is blurred or out of focus.

  When the determination unit 74 determines that the image is defective, the special image generation unit 78 generates a special image signal 107 by overlapping information 106 related to warning display on the blood vessel emphasized image signal 100. To do. For example, as information regarding the warning display, as shown in FIG. 17, “current image is“ defective image ”” is displayed in the upper right area on the monitor 18. When the determination unit 74 determines that the image is defective, the special image generation unit 78 does not display information based on the blood vessel and the blood vessel index value with respect to the blood vessel emphasized image signal 100 (that is, overlap). (Do not process). For example, when the coloring process is performed according to the blood vessel index value, the coloring process is not performed when the determination unit 74 determines that the image is defective. Note that the warning display may be performed when the image correction unit 76 has a very large movement amount and cannot be aligned.

  The video signal generation unit 68 converts the image signal received from the normal image processing unit 66 or the special image generation unit 78 into a video signal to be displayed as an image that can be displayed on the monitor 18, and sequentially outputs the video signal to the monitor 18. Thus, the normal image is displayed on the monitor 18 when a normal image signal is input, and the special image is displayed when a special image signal is input.

  Next, the operation of the present invention will be described along the flowchart shown in FIG. First, screening is performed in the normal observation mode (S11). At the time of this screening, if a site with potential lesion such as a brownish area or redness (hereinafter referred to as a possible lesion) is found (S12), the doctor stops the movement operation of the endoscope 12 (S13). Then, the mode switching SW 12f is operated to switch the observation mode to the special observation mode (S14).

  In the special observation mode, the observation target is imaged at the first timing to acquire an image signal (S15). A blood vessel to be observed is extracted from the image signal (S16), and a blood vessel image signal representing the blood vessel to be observed is generated (S17). A blood vessel index value obtained by indexing a blood vessel is calculated from the generated blood vessel image signal (S18). Then, the defective image is determined using the blood vessel index value (S19).

  At the time of determination, first, the blood vessel index value at the first timing is compared with the blood vessel index value at the second timing before the first timing, and for the blood vessel index value at the second timing, When the blood vessel index value at the first timing changes by a certain value or more, it is determined as a defective image. When the blood vessel index value at the first timing is less than a certain value with respect to the blood vessel index value at the second timing, the frequency analysis is performed on the blood vessel image signal at the first timing, The high-frequency component contained in the blood vessel image signal at the timing is less than the high-frequency component contained in the blood vessel image signal at the second timing, and the low-frequency component contained in the blood vessel image signal at the first timing is the blood vessel at the second timing. When there are more than low frequency components included in the image signal, it is determined that the image is defective. On the other hand, the high frequency component included in the blood vessel image signal at the first timing is equal to or higher than the high frequency component included in the blood vessel image signal at the second timing, and the low frequency component included in the blood vessel image signal at the first timing. Is less than the low frequency component included in the blood vessel image signal at the second timing, it is determined that the image is not a defective image.

  When it is determined that the image is a defective image, the movement amount between the blood vessel image signal at the first timing and the blood vessel image signal at the second timing is calculated, and the movement amount is used to calculate the first timing. Image correction processing for aligning the blood vessel represented in the blood vessel image signal and the blood vessel represented in the blood vessel image signal at the second timing is performed (S20). On the other hand, when it is determined that the image is not defective, the image correction process is not performed. Thereafter, a special image signal is generated using the image signal acquired at the first timing, the blood vessel image signal subjected to post-determination processing, and the blood vessel index value (S21). Then, a special image is generated based on the special image signal (S22), and this special image is displayed on the monitor 18 (S23). The special observation mode is repeated until the normal observation mode is switched (S24) or the diagnosis is completed (S25).

  As described above, in the special observation mode, the present invention extracts a blood vessel from the image signal acquired at the first timing, and uses the blood vessel index value calculated from the extracted blood vessel to perform the first timing. It is possible to accurately determine whether an image is a defective image. And since the post-determination process according to the determination result is performed on the image signal acquired at the first timing, information about the blood vessel can be accurately displayed.

[Second Embodiment]
In the first embodiment, when it is determined that the image is a defective image, the image correction process is performed on the blood vessel image signal at the first timing. In the second embodiment, the blood vessel index at the first timing is used. An index value correction process is performed on the value. As shown in FIG. 19, in the second embodiment, a special image processing unit 110 is provided instead of the special image processing unit 67. The special image processing unit 110 includes an index value correction unit 114 (post-determination processing unit) and a blood vessel position correction unit 116. Since other members are the same as those in the first embodiment, the description thereof is omitted.

  As illustrated in FIG. 20, the index value correction unit 114 includes a signal switching unit 120, a movement amount calculation unit 121, and a correction processing unit 122.

  The signal switching unit 120 receives the determination result from the determination unit 74 and the blood vessel index value from the blood vessel index value calculation unit 72. If the determination result is a defective image, the signal switching unit 120 transmits the blood vessel index value to the correction processing unit 122. If it is not a defective image, the transmission destination is switched so that the blood vessel index value is transmitted to the special image generation unit 78.

  The movement amount calculation unit 121 receives the blood vessel image signal from the blood vessel extraction unit 70 and calculates the movement amount between the blood vessel image signal at the first timing and the blood vessel image signal at the second timing. The calculation of the movement amount is the same as that of the movement amount calculation unit 97 of the first embodiment, and is expressed in the blood vessel represented in the blood vessel image signal at the first timing and the blood vessel image signal in the second timing. For the pixel corresponding to the blood vessel, the amount of movement in the X direction and the amount of movement in the Y direction are calculated by performing a comparison operation of the image signals.

  The correction processing unit 122 receives the blood vessel index value from the signal switching unit 120 and the movement amount from the movement amount calculation unit 121, and performs an index value correction process on the blood vessel index value at the first timing according to the magnitude of the movement amount. Run. The blood vessel index value is calculated as a correct numerical value when the movement amount is zero (when there is no blur or blur), and the change from the correct numerical value increases as the movement amount increases. Therefore, an accurate blood vessel index value can be obtained by performing the index value correction process on the blood vessel index value by the amount of movement.

  The blood vessel position correction unit 116 receives the blood vessel image signal from the blood vessel extraction unit 70 and the movement amount from the index value correction unit 114, and uses the movement amount to represent the blood vessel represented in the blood vessel image signal at the first timing, Position alignment with the blood vessel represented in the blood vessel image signal at timing 2 is performed (see FIG. 19). Regarding the alignment, similarly to the alignment unit 98 of the above-described embodiment, the blood vessel image signal at the first timing is moved in a direction to cancel the positional deviation by the amount of movement. Thereby, the position of the blood vessel represented in the blood vessel image signal at the first timing is matched with the position of the blood vessel represented in the blood vessel image signal at the second timing. The blood vessel image signal after alignment is transmitted to the special image generation unit 78. Similar to the first embodiment, the special image generation unit 78 performs overlap processing on information based on the blood vessel index value, overlap processing on information related to warning display, and information based on the blood vessel index value according to the determination result. Processing such as displaying is performed.

  As described above, in the second embodiment, an accurate blood vessel index value can be obtained by performing the index value correction process on the blood vessel index value at the first timing, so that information related to blood vessels can be accurately displayed.

[Third Embodiment]
In the third embodiment, the observation target is illuminated using a laser light source and a phosphor instead of the four-color LEDs 20a to 20d shown in the first and second embodiments. The rest is the same as in the first embodiment.

  As shown in FIG. 21, in the endoscope system 200 of the second embodiment, in the light source device 14, instead of the four color LEDs 20a to 20d, a blue laser light source (see FIG. 21) that emits blue laser light having a central wavelength of 445 ± 10 nm. 21, a blue-violet laser light source (denoted as “405LD” in FIG. 21) 206 that emits blue-violet laser light having a center wavelength of 405 ± 10 nm is provided. Light emission from the semiconductor light emitting elements of these light sources 204 and 206 is individually controlled by the light source control unit 208, and the light quantity ratio between the emitted light of the blue laser light source 204 and the emitted light of the blue-violet laser light source 206 is freely changeable. It has become.

  The light source control unit 208 drives the blue laser light source 204 in the normal observation mode. On the other hand, in the special observation mode, both the blue laser light source 204 and the blue violet laser light source 206 are driven, and the emission ratio of the blue laser light is larger than the emission ratio of the blue violet laser light. I have control. The laser beams emitted from the light sources 204 and 206 are incident on the light guide 41 through optical members (all not shown) such as a condenser lens, an optical fiber, and a multiplexer.

  Note that the full width at half maximum of the blue laser beam or the blue-violet laser beam is preferably about ± 10 nm. As the blue laser light source 204 and the blue-violet laser light source 206, a broad area type InGaN laser diode can be used, and an InGaNAs laser diode or a GaNAs laser diode can also be used. In addition, a light-emitting body such as a light-emitting diode may be used as the light source.

  In addition to the illumination lens 45, the illumination optical system 30a is provided with a phosphor 210 on which blue laser light or blue-violet laser light from the light guide 41 is incident. When the phosphor 210 is irradiated with the blue laser light, the phosphor 210 emits fluorescence. Some of the blue laser light passes through the phosphor 210 as it is. The blue-violet laser light is transmitted without exciting the phosphor 210. The light emitted from the phosphor 210 is irradiated into the specimen through the illumination lens 45.

  Here, in the normal observation mode, mainly the blue laser light is incident on the phosphor 210. Therefore, as shown in FIG. 22, the blue laser light and the fluorescence emitted from the phosphor 210 by the blue laser light are combined. White light is irradiated to the observation target. On the other hand, in the special observation mode, since both the blue-violet laser beam and the blue laser beam are incident on the phosphor 210, the phosphor is generated by the blue-violet laser beam, the blue laser beam, and the blue laser beam as shown in FIG. Special light obtained by combining fluorescence excited and emitted from 210 is irradiated into the specimen.

The phosphor 210 absorbs part of the blue laser light and emits green to yellow excitation light (for example, YAG phosphor or phosphor such as BAM (BaMgAl ₁₀ O ₁₇ )). It is preferable to use what is comprised including. If a semiconductor light emitting device is used as an excitation light source for the phosphor 210 as in this configuration example, high intensity white light can be obtained with high luminous efficiency, and the intensity of white light can be easily adjusted. Changes in temperature and chromaticity can be kept small.

[Fourth Embodiment]
In the fourth embodiment, instead of the four-color LEDs 20a to 20d shown in the first and second embodiments, the observation target is illuminated using a broadband light source such as a xenon lamp and a rotary filter. Further, instead of the color image sensor 48, the observation target is imaged by a monochrome image sensor. The rest is the same as in the first embodiment.

  As shown in FIG. 24, in the endoscope system 300 of the third embodiment, the light source device 14 is provided with a broadband light source 302, a rotary filter 304, and a filter switching unit 305 instead of the four-color LEDs 20a to 20d. Yes. The imaging optical system 30b is provided with a monochrome imaging sensor 306 that is not provided with a color filter, instead of the color imaging sensor 48.

  The broadband light source 302 is a xenon lamp, a white LED, or the like, and emits white light having a wavelength range from blue to red. The rotary filter 304 includes a normal observation mode filter 308 provided on the inner side and a special observation mode filter 309 provided on the outer side (see FIG. 25). The filter switching unit 305 moves the rotary filter 304 in the radial direction. When the normal switching mode is set by the mode switching SW 12f, the normal switching mode filter 308 of the rotating filter 304 is inserted into the white light path. When the special observation mode is set, the special observation mode filter 309 of the rotation filter 304 is inserted into the optical path of white light.

  As shown in FIG. 25, the normal observation mode filter 308 includes, along the circumferential direction, a B filter 308a that transmits blue light of white light, a G filter 308b that transmits green light of white light, and white light. Among them, an R filter 308c that transmits red light is provided. Therefore, in the normal observation mode, the rotation filter 304 is rotated, so that blue light, green light, and red light are alternately irradiated on the observation target.

  The special observation mode filter 309 includes, along the circumferential direction, a Bn filter 309a that transmits blue narrow-band light having a specific wavelength among white light, a G filter 309b that transmits green light among white light, and white light. Among them, an R filter 309c that transmits red light is provided. Therefore, in the special observation mode, the rotation filter 304 is rotated so that blue narrow band light, green light, and red light are alternately irradiated on the observation target.

  In the endoscope system 300, in the normal observation mode, the monochrome imaging sensor 306 images the inside of the specimen every time blue light, green light, and red light are irradiated on the observation target. Thereby, RGB image signals of three colors are obtained. Based on the RGB image signals, a normal image is generated by the same method as in the first embodiment.

  On the other hand, in the special observation mode, the monochrome imaging sensor 306 images the inside of the specimen every time the observation target is irradiated with blue narrow band light, green light, and red light. Thereby, a Bn image signal, a G image signal, and an R image signal are obtained. A special image is generated based on the Bn image signal, the G image signal, and the R image signal. For the generation of the special image, a Bn image signal is used instead of the B image signal. Other than that, a special image is generated in the same manner as in the first embodiment.

  In the above embodiment, the special image processing unit determines whether the image at the first timing is a defective image. If the image is a defective image, the special image processing unit performs image correction processing or index value correction processing. However, the normal image processing unit may determine whether or not the image is a defective image, and may perform an image correction process or an index value correction process when the image is a defective image.

10, 200, 300 Endoscope system 12 Endoscope 14 Light source device 16 Processor device 20 Light source 53 Image signal acquisition unit 67, 110 Special image processing unit 70 Blood vessel extraction unit 72 Blood vessel index value calculation unit 74 Determination unit 76 Image correction unit 78 Special image generation unit 97, 121 Movement amount calculation unit 98 Position alignment unit 116 Blood vessel position correction unit 114 Index value correction unit 122 Correction processing unit

Claims (19)

An image signal acquisition unit that acquires image signals obtained by imaging an observation target with an endoscope at different timings;
A blood vessel extraction unit that extracts a blood vessel from the image signal and generates a blood vessel image signal;
A blood vessel index value calculation unit for calculating a blood vessel index value from the extracted blood vessels;
A determination unit that determines whether the image based on the image signal is a defective image with respect to the sharpness from the blood vessel index value;
A post-determination processing unit that performs processing based on the determination result on at least one of the blood vessel image signal and the blood vessel index value ;
Equipped with a,
The processor unit for an endoscope , wherein the determination unit determines that the image is a defective image when the blood vessel index value changes by a predetermined value or more . The blood vessel index value calculation unit calculates the blood vessel index value from at least one of a blood vessel width, a blood vessel density, the number of blood vessels, a blood vessel traveling direction, a blood vessel shape, and a blood vessel sharpness. The processor device according to claim 1 . The image signal acquisition unit acquires an image signal at a first timing, acquires an image signal at a second timing before the first timing,
The blood vessel extraction unit extracts a blood vessel from the image signal acquired at the first timing by generating a blood vessel image signal at the first timing by extracting a blood vessel from the image signal acquired at the first timing. To generate a blood vessel image signal at the second timing,
The blood vessel index value calculation unit calculates a blood vessel index value at the first timing based on a blood vessel extracted from the image signal acquired at the first timing, and from the image signal acquired at the second timing. Calculating a blood vessel index value of the second timing based on the extracted blood vessels;
The determination unit, when the blood vessel index value at the first timing changes by a predetermined value or more with respect to the blood vessel index value at the second timing, determines that the image is the defective image. 2. The processor device according to 2 .   The processor device according to claim 1, further comprising an image generation unit configured to generate an image based on the determination result. The processor apparatus according to claim 4 , wherein the post-determination processing unit includes an image correction unit that performs an image correction process on an image based on the image signal when it is determined that the image is a defective image. The image signal acquisition unit acquires an image signal at a first timing, acquires an image signal at a second timing before the first timing,
6. The processor device according to claim 5 , wherein the image correction unit performs the image correction processing based on the image signal at the second timing. A movement amount calculation unit for calculating a movement amount between the image signal at the first timing and the image signal at the second timing;
An alignment unit that aligns the blood vessel of the first timing and the blood vessel of the second timing from the movement amount;
The processor device according to claim 6 , wherein the image correction unit performs the image correction processing based on the movement amount. The image generation unit generates an image in which the blood vessel at the second timing overlaps the image at the first timing when it is determined that the image is the defective image. Item 8. The processor device according to Item 7 . The blood vessel index value calculation unit calculates a blood vessel index value at the first timing based on a blood vessel extracted from the image signal acquired at the first timing, and from the image signal acquired at the second timing. Calculating a blood vessel index value of the second timing based on the extracted blood vessels;
When it is determined that the image is the defective image, the image generation unit generates an image in which information based on the blood vessel index value at the second timing is overlapped with the image at the first timing. 9. A processor device according to claim 7 or 8, wherein: The processor device according to claim 9 , wherein the image generation unit replaces the blood vessel index value at the first timing with the blood vessel index value at the second timing. The processor apparatus according to claim 4 , wherein the post-determination processing unit includes an index value correction unit that performs an index value correction process on the blood vessel index value when it is determined that the image is a defective image. The image signal acquisition unit acquires an image signal at a first timing, acquires an image signal at a second timing before the first timing,
12. The processor device according to claim 11, wherein the index value correction unit performs the index value correction processing based on the image signal at the second timing. A movement amount calculation unit for calculating a movement amount between the image signal at the first timing and the image signal at the second timing;
13. The processor device according to claim 12, wherein the index value correction unit performs the index value correction processing based on the movement amount. 14. The processor device according to claim 13 , further comprising a blood vessel position correction unit that adjusts the blood vessel at the first timing to the position of the blood vessel at the second timing based on the movement amount. The image generation unit generates an image in which the blood vessel at the second timing overlaps the image at the first timing when it is determined that the image is the defective image. Item 15. The processor device according to Item 14 . The blood vessel index value calculating unit calculates a blood vessel index value at the second timing based on a blood vessel extracted from the image signal acquired at the second timing;
When it is determined that the image is the defective image, the image generation unit generates an image in which information based on the blood vessel index value at the second timing is overlapped with the image at the first timing. The processor device according to claim 14 or 15, The image generation unit, when the it is determined to be defective image, information based on the blood vessel, and any one of claims 4 to 16, characterized in that the hidden information based on the blood vessel index value 1 A processor device according to item. 18. The processor device according to claim 4 , wherein the image generation unit displays a warning for an image based on the image signal when it is determined that the image is a defective image. An image signal acquisition unit acquiring image signals obtained by imaging an observation target with an endoscope at different timings;
A blood vessel extraction unit extracting a blood vessel from the image signal to generate a blood vessel image signal;
A blood vessel index value calculating unit calculating a blood vessel index value from the extracted blood vessels;
A step of determining whether the image based on the image signal is a defective image with respect to sharpness from the blood vessel index value;
A step in which the post-determination processing unit performs processing based on the result of the determination for at least one of the blood vessel image signal and the blood vessel index value ;
Equipped with a,
The operation method of the processor device for an endoscope , wherein the determination unit determines that the image is a defective image when the blood vessel index value changes by a predetermined value or more .

Images