JP2012134875A - Endoscope device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an endoscope device capable of changing the details of image processing depending on a change in a use environment and minimizing the degradation of measuring accuracy.SOLUTION: In an endoscope device, a signal picked up by an imaging device 8 using objective optical systems 7a and 7b having a parallax is input in a first image processing part 16 and a second image processing part 17 of an image processing part 15 through a video signal processing part 14. Following to an instruction from an image processing part selection part 19 that refers a reference data tabulated in advance in a storage part 20 according to a use environment depending on a detection temperature, the first image processing part 16 performs image processing by one unit of processing details among a plurality of processing details and outputs a pair of measurement images to a measurement part 18. The measurement part 18, then, measures the distance, area, and the like of the object to be inspected using the pair of measurement images and outputs the measurement result to an image display unit 4.

Description

  The present invention relates to an endoscope apparatus that measures a subject from an image obtained by driving an imaging device mounted on a distal end portion of an insertion portion.

2. Description of the Related Art Endoscope apparatuses that insert an endoscope insertion portion into a subject and image the inside of the subject with an imaging element mounted at the distal end of the insertion portion are widely used in the industrial field. Some endoscope apparatuses have a measurement function for measuring a distance, an area, and the like in a subject by imaging the subject and performing image processing on the captured image.
As a conventional example of an endoscope apparatus having such a measurement function, as disclosed in JP-A-10-248806, for example, it has two optical systems for stereo measurement and uses the parallax thereof. There is something. In this conventional example, corresponding points in two images generated by two optical systems having parallax are detected by matching processing, and a three-dimensional coordinate position is detected using the principle of triangulation.

Further, in the conventional endoscope apparatus, the original captured image data of the imaging signal is not displayed on the image display apparatus as it is, but is displayed on the display image displayed on the monitor by performing various image processing and displaying it. The visibility and reproducibility of the subject are improved.
For example, a CCD image sensor (hereinafter abbreviated as CCD) and a CMOS image sensor used as an imaging device for an endoscope have the following problems and are eliminated or reduced by image processing.
a. A pixel defect is easily generated, and a pixel portion where the pixel defect has occurred is displayed as a white bright spot or a black spot depending on the image of the subject. In this case, the pixel defect is made inconspicuous by performing pixel defect correction processing that complements the defect data of the defective pixel from the data of the peripheral pixels.

b. Sensitive to temperature changes, the fixed pattern noise increases as the temperature increases (the dark current increases and the noise increases as the temperature increases). In this case, the fixed pattern noise is extracted and filtered based on the difference between the black captured image and the captured image of the subject, and the fixed pattern noise is reduced / removed.
In addition, in order to improve the accuracy of the filtering process, correspondence data on how to generate the temperature and fixed pattern noise is prepared in advance, and a filtering process corresponding to the temperature is performed based on the data. Thereby, fixed pattern noise is reduced.
c. In the CMOS image sensor, an amplifier is prepared for each pixel, but fixed pattern noise occurs due to variations in the characteristics of the amplifier. In this case, the fixed pattern noise is extracted and filtered based on the difference between the black captured image and the captured image of the subject, thereby reducing / removing the fixed pattern noise.

2. Description of the Related Art Conventionally, an insertion portion of an endoscope apparatus is very thin, and since a physical space inside the distal end of the insertion portion is narrow, an image sensor is often used with a small size (low pixel).
In addition, since the number of pixels of the image sensor is low, upscaling is often performed when displaying on a monitor. In this case, if a pixel defect has occurred, the defective pixel is also enlarged, so that a pixel defect correction function is important in order to maintain a predetermined image quality.
In addition, because the insertion section is very long and thin for the convenience of the endoscope's usage environment and applications, it is an electrical signal for driving the image sensor placed inside the insertion section and transmitting the imaging signal. The line is long and thin. As a result, it is electrically disadvantageous, noise is superimposed on the image pickup signal, and image noise is likely to occur. Therefore, there is a tendency that filtering processing for reducing noise is strongly performed.
As described above, in the endoscope apparatus, the pixel defect correction process and the filtering process are indispensable processes, and are more important than other general camera apparatuses.

However, in the conventional endoscope apparatus in which the function of measuring the distance between the distal end of the insertion portion and the subject, the size (area / length) of the scratch on the subject, and the like is mounted, Processing may be the main cause of degradation of measurement accuracy.
In the measurement technology of the endoscope apparatus of the conventional example, the corresponding distortion point of the parallax image is matched and the geometric distortion of the image data is detected by detecting the three-dimensional coordinate position by triangulation using the parallax image. However, depending on the imaging environment or imaging environment in which the subject is imaged, accuracy degradation occurs as described below.
A. If fixed pattern noise is superimposed on the image, the luminance distribution will deviate from the actual object, so when matching the parallax image using the image after image processing, depending on the change in the luminance information of each image, the corresponding point There is a risk that the measurement accuracy will deteriorate.

B. On the other hand, if filtering processing is performed to remove noise, there is a possibility that the image information that is originally required may be removed as noise. In this case, the corresponding points are shifted as in the above case, and the measurement accuracy is degraded. There is a case to let you.
C. When performing pixel defect correction processing, it is complemented from the data of surrounding pixels, but if noise components are superimposed on the surrounding pixels, there is a possibility that the corrected luminance distribution may deviate from the real thing. In addition, the corresponding points may be shifted and the measurement accuracy may be degraded.
Therefore, an endoscope apparatus that can change the contents of image processing in accordance with changes in the use environment (or imaging environment) and can reduce deterioration in measurement accuracy using images is desired.
The present invention has been made in view of the above-described points, and an object of the present invention is to provide an endoscope apparatus that can change the contents of image processing in accordance with a change in use environment and can reduce deterioration in measurement accuracy.

  An endoscope apparatus according to the present invention is provided at a distal end portion of an insertion portion, and images an optical image of a subject using a pair of objective optical systems having parallax, and is photoelectrically converted by the imaging device. A video signal processing unit that converts a captured image signal into a video signal, and a pair of measurement images based on the pair of objective optical systems by performing image processing on the image of the video signal generated by the video signal processing unit The image processing unit for generating the image, the measurement unit for measuring the subject using the pair of measurement images generated by the image processing unit, and the processing content of the image processing for the image processing unit An image processing selection unit for instructing, and a storage unit for storing reference data serving as a reference for determining the processing content of the image processing, the reference data corresponding to a use environment in which measurement by the measurement unit is performed And reduce noise as the image processing One of a plurality of processing contents for at least one of filtering processing and pixel defect correction processing, wherein the image processing selection unit refers to reference data stored in the storage unit, and the use environment And instructing the image processing unit to select one of a plurality of processing contents of the image processing, and the image processing unit, based on the selection instruction from the image processing selection unit, The pair of measurement images used for measurement by the measurement unit is generated by image processing according to one of a plurality of processing contents for at least one of the pixel defect correction processing.

  According to the present invention, the content of image processing can be changed in accordance with changes in the usage environment, and degradation in measurement accuracy can be reduced.

FIG. 1 is a diagram showing an overall configuration of an endoscope apparatus according to a first embodiment of the present invention. FIG. 2 is a block diagram showing the configuration of the image processing unit. FIG. 3 is a diagram showing a state in which an image when the same subject is displayed on an image display device using left and right objective optical systems, and measurement results of distances and areas measured by a measurement unit are displayed. FIG. 4 is a diagram illustrating a specific example of reference data stored in a table in the storage unit. FIG. 5 is a flowchart showing processing for changing the processing contents of ON / OFF of the filtering processing according to whether the detected temperature is equal to or higher than a predetermined temperature. FIG. 6 is a flowchart showing processing for changing the processing content of the strength (level) of filtering processing according to whether the detected temperature is equal to or higher than a predetermined temperature. FIG. 7 is a flowchart showing processing for changing the processing content of the size of the spatial filter of the filtering processing according to whether or not the detected temperature is equal to or higher than a predetermined temperature. FIG. 8 is a flowchart showing processing for changing the processing contents of ON / OFF of chroma suppress as filtering processing depending on whether the detected temperature is equal to or higher than a predetermined temperature. FIG. 9 is a flowchart showing a process for changing the content of processing with and without pixel defect correction processing depending on whether or not the detected temperature is equal to or higher than a predetermined temperature. FIG. 10 is a flowchart showing processing for changing the processing content of a pixel range used for correction around a defective pixel when performing pixel defect correction processing depending on whether the detected temperature is equal to or higher than a predetermined temperature. FIG. 11 is a diagram showing an overall configuration of an endoscope apparatus according to a second embodiment of the present invention. FIG. 12 is a process for generating a measurement evaluation image with two types of processing contents of filtering processing ON and OFF, performing measurement, and setting a measurement image according to the measurement result when the detected temperature is equal to or higher than a predetermined temperature. The flowchart which shows. FIG. 13 shows that when a detected temperature is equal to or higher than a predetermined temperature, a measurement evaluation image is generated with two types of processing contents with and without pixel defect correction processing, measurement is performed, and a measurement image is set according to the measurement result. The flowchart which shows the process to do. In FIG. 14, when the detected temperature is equal to or higher than a predetermined temperature, an image for measurement evaluation is generated with two types of processing contents in which the pixel range used for correction around the defective pixel is changed, the measurement is performed, and the measurement is performed according to the measurement result. 6 is a flowchart showing processing for setting a work image.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
As shown in FIG. 1, an endoscope apparatus 1 according to the present invention has an elongated insertion portion 2 inserted into a subject such as a jet engine and a rear end (base end) of the insertion portion 2 connected to each other. An endoscope apparatus main body 3 that performs signal processing and the like, and an image display that is connected to the endoscope apparatus main body (hereinafter simply abbreviated as a main body) 3 and displays an endoscope image (abbreviated simply as an image). Device 4.
A light emitting diode (LED) 6 as an illuminating means for illuminating the subject such as a blade inside the subject is provided at the distal end portion 5 of the insertion portion 2 and a pair of objective optical systems 7a for imaging the illuminated subject. 7b is provided.
The objective optical systems 7a and 7b are arranged so as to have a parallax with respect to the subject, and a single CCD or the like that captures an optical image of the subject at the imaging position of both objective optical systems 7a and 7b. An imaging surface of the imaging element 8 such as a CMOS imager is disposed. In the present embodiment, the subject image formed by the two left and right optical systems is formed on the imaging surface of the image sensor 8 in a state having parallax.

The objective optical systems 7a and 7b and the imaging device 8 form an imaging means for imaging the subject.
In the present embodiment, by using two objective optical systems 7a and 7b having a known parallax, stereo measurement (stereoscopic measurement) can be performed using the principle of triangulation.
The data of the optical characteristics of the two objective optical systems 7a and 7b are stored in a storage unit and other storage units (to be described later) inside the main body unit 3. In addition, FIG. 1 shows a configuration example in which two objective optical systems 7a and 7b are integrally provided at the distal end portion 5 of the insertion portion 2. However, an optical adapter provided with two objective optical systems 7a and 7b is shown. You may make it the structure connected to the front-end | tip part 5 so that attachment or detachment is possible. In this embodiment, the left and right images are connected to one image sensor 8, but two image sensors may be used.

The LED 6 is connected to the LED driving unit 11 inside the main body 3 through a power line 9 inserted through the insertion unit 2, and the LED 6 emits and emits light by the LED driving power supplied from the LED driving unit 11. Illuminate the subject with illumination light.
Instead of using the LED 6, the light generated by a light source such as a lamp provided in the main body 3 is transmitted by a light guide as illumination light transmission means (or light guiding means) inserted into the insertion portion 2, You may make it the structure radiate | emitted as illumination light from an illumination window.
The image pickup device 8 is also connected to the image pickup device drive unit 13 and the video signal processing unit 14 inside the main body unit 3 by signal lines 12 a and 12 b inserted through the insertion unit 2. The image sensor drive unit 13 generates an image sensor drive signal and applies the image sensor drive signal to the image sensor 8. The imaging element 8 outputs an imaging signal corresponding to a captured image obtained by photoelectrically converting the optical image (captured by the imaging element 8) by applying an imaging element driving signal.

The imaging signal is input to the video signal processing unit 14, and the video signal processing unit 14 generates a video signal based on the imaging signal.
The video signal generated by the video signal processing unit 14 is input to an image processing unit 15 that performs various types of image processing on the image of the video signal. The image of the video signal is a pair of images corresponding to the left and right subject images formed on the imaging element 8 by the pair of objective optical systems 7a and 7b.
The image processing unit 15 performs various types of image processing on the (pair) images of the video signal generated by the video signal processing unit 14, and the image processing unit 15 includes the first image processing unit 16. And the second image processing unit 17 and the second image processing unit 17.

The first image processing unit 16 performs image processing on the (pair) image of the video signal and outputs the image to the measurement unit 18 as a (pair) measurement image used for measurement.
On the other hand, the second image processing unit 17 performs image processing on the (pair) image of the video signal and outputs a display (pair) image to the image display device 4, which is displayed on the image display device 4. Display a (pair) image for use. This image corresponds to an image of the subject imaged on the image sensor 8 that has been subjected to various types of image processing.
The measurement unit 18 performs measurement processing on the subject using the (pair) measurement images, outputs a video signal subjected to the measurement processing to the image display device 4, and includes the subject in the image display device 4. The measurement processing result is displayed in the image.

In the present embodiment, for example, the main body unit includes an image processing selection unit 19 that instructs the first image processing unit 16 in the image processing unit 15 to specify the content of the image processing, and a reference when determining the content of the image processing. And storage unit 20 having reference data.
Further, in the present embodiment, in order to detect an environmental temperature that forms a use environment in which measurement is performed by the measurement unit 18, the image sensor 8 is provided in the vicinity of the image sensor 8 mounted in the distal end portion 5 of the insertion unit 2. A temperature sensor 21 for detecting the temperature of is arranged. A sensor signal from the temperature sensor 21 is input to the temperature detection unit 23 in the main body 3 via the signal line 22. The temperature detector 23 converts the sensor signal into temperature data.

The image processing selection unit 19 takes in the reference data stored in the storage unit 20 corresponding to the temperature data from the temperature detection unit 23, and receives an instruction signal for instructing or selecting the content of the image processing by the first image processing unit 16. Output.
Therefore, the first image processing unit 16 performs various image processing in accordance with the instruction signal from the image processing selection unit 19. On the other hand, the second image processing unit 17 performs various types of image processing regardless of the instruction signal from the image processing selection unit 19 so that an image with improved visibility can be displayed.
The measurement instruction unit 24 that outputs a measurement instruction signal such as distance or area to the measurement unit 18 is also output to the image processing selection unit 19 in addition to the measurement unit 18. The image processing selection unit 19 acquires, through the temperature detection unit 23, detected temperature information as an environmental temperature that forms a use environment at a timing when a measurement instruction signal is input.

Then, the image processing selection unit 19 compares the detected temperature information with the table data (see FIG. 4) of the image processing method corresponding to the temperature stored in the storage unit 20, and the reference data corresponding to the detected temperature. Select.
FIG. 2 shows the configuration of the periphery of the image processing unit 15. The luminance signal Y and the chroma signals U and V output from the video signal processing unit 14 are input to the first image processing unit 16 and the second image processing unit 17 in the image processing unit 15.
The first image processing unit 16 includes a filtering processing circuit 31a that reduces fixed pattern noise due to dark current and a pixel defect correction processing circuit 32a that corrects pixel defects as circuits that perform various types of image processing. The measurement image (generated by these image processes) is output to the measurement unit 18.

Note that the filtering process is performed by turning on the fixed pattern noise to reduce it. In addition, the chroma signals U and V are allowed when the color noise becomes conspicuous when superimposed on the chroma signals U and V. This also includes the case of processing to reduce color noise by suppressing within the range (described later).
The second image processing unit 17 also includes a filtering processing circuit 31b that reduces fixed pattern noise due to dark current and the like, and a pixel defect correction processing circuit 32b that corrects pixel defects, but the second image processing unit 17 includes the first image. Unlike the processing unit 16, it is not affected by an instruction from the image processing selection unit 19. Note that a gamma correction circuit, a contour enhancement circuit, and the like (not shown) are provided in the video signal processing unit and perform processing such as gamma correction and contour enhancement.
Video signals of display images subjected to various types of image processing by the second image processing unit 17 are output to the image display device 4, and the image of the subject imaged on the image sensor 8 is visible in the image display device 4. Etc. are displayed as an improved image.

FIG. 3 shows a display example of the image of the subject on the image display device 4. FIG. 3 shows left and right images when the same subject is imaged by the objective optical systems 7 a and 7 b having parallax on the left and right, subjected to image processing by the second image processing unit 17 and displayed on the image display device 4. The figure on the left side of FIG. 3 shows how the distance is measured.
The user of the endoscope apparatus 1 performs a plurality of measurements on one of the displayed left and right images (for example, the right image) by operating a mouse (not shown) provided in the measurement instruction unit 24. A position is designated and the measurement unit 18 is instructed to measure a distance between a plurality of positions.
For example, the user may desire to know the size of a wound made on the surface of the subject. In this case, the user designates two positions that are both ends of the wound for one image (for example, the right image), and instructs the measurement unit 18 to measure the distance between the two positions. .

In this case, the measurement instruction signal is also input to the image processing selection unit 19, and the image processing selection unit 19 selects reference data corresponding to the use environment to which the signal is input from the storage unit 20, and the reference data Accordingly, the processing content of the image processing of the first image processing unit 16 is determined (defined). Then, the first image processing unit 16 performs image processing according to the processing content of the image processing corresponding to the selection instruction from the image processing selection unit 19.
The measurement unit 18 uses a pair of measurement images of video signals output from the first image processing unit 16, that is, left and right measurement images, and designates a plurality of designated images in one (right or left) measurement image. Measurement processing is performed to calculate the corresponding position in the other (left or right) measurement image corresponding to each position.

And the result of the measurement process of the distance between several positions is output to the image display apparatus 4, and the distance as a result of a measurement process is displayed as shown on the left side of FIG. Moreover, the right side of FIG. 3 shows a state where the area measurement is performed.
In addition, there are cases where the user has a deformed area formed on the surface of the subject and desires to calculate the area of the deformed area. In such a case, the user designates a plurality of positions so as to surround a region deformed by the measurement instruction unit with respect to one image (for example, the right image), and measures the area with respect to the measurement unit 18. Instruct.
Also in this case, the measurement unit 18 performs measurement processing for calculating corresponding positions in the other measurement image respectively corresponding to a plurality of designated positions in the one measurement image.

Then, an area calculation measurement process is performed from the results of the distance measurement process between a plurality of positions, the area measurement result is output to the image display device 4, and the area as a result of the measurement process as shown on the right side of FIG. Is displayed.
In the present embodiment, when performing distance measurement, area measurement, and the like in this way, the processing content of the image processing is changed according to the reference data stored in the storage unit 20 in response to a change in the use environment. Then, by changing the contents of the image processing according to the reference data in this way, even when the usage environment changes, deterioration in measurement accuracy is prevented or reduced.
FIG. 4 shows an example of the reference data stored in advance in the storage unit 20 and tabulated.

In this storage unit 20, whether or not to perform filtering processing on each temperature data (that is, filtering processing ON / OFF), the strength of the filtering processing when filtering, the size of the spatial filter (in the filtering processing) Whether to suppress the chroma signal (that is, chroma suppression ON / OFF), whether to perform pixel defect correction processing (that is, pixel defect correction processing ON / OFF), and the correction reference range when performing pixel defect correction processing Is stored.
Note that the predetermined temperatures X1, X2, X3, etc. in FIG. 4 have a relationship of X1 <X2 <... As described in the remarks column of FIG. That is, the lower side of the table corresponds to the reference data when the temperature is high. Further, the levels L1, L2,... Representing the strength of the filtering process have a relationship of L1 <L2 <. On the other hand, the size of the spatial filter when performing the filtering process has a relationship of A> B. Note that the temperature X1 in FIG. 4 represents, for example, a normal temperature region, and X3 represents a high temperature region.

The reference data shown in FIG. 4 is classified from the measurement data accumulated in the past by actually performing the filtering process ON and OFF, the pixel defect correction process ON and OFF, etc. at each temperature. The processing contents when a highly accurate measurement result is obtained at the temperature are determined. Therefore, if the measurement image is generated according to the processing content of the reference data shown in FIG. 4, it is possible to perform highly accurate measurement in many cases.
In the present embodiment, the storage unit 20 is configured by a storage unit such as a rewritable flash memory, and the reference data can be updated to more reliable reference data based on the accumulation result of further measurement data. Yes.
For example, in the table of FIG. 4, when the temperature in the usage environment is equal to or higher than the predetermined temperature X3, the filtering process is turned from OFF to ON, and when it is turned ON, the filtering process is performed depending on whether the temperature is higher than the predetermined temperature. The intensity (level) changes.

Further, the filtering process tends to be performed when the temperature is high and the size of the spatial filter is smaller than when the temperature is low. In FIG. 4, for example, at temperatures X1 and X2, the filtering process is normally set to OFF, but may be set to ON by selection from the user. The used levels L1, L2, size A × A, and the like are also stored.
In addition, when performing pixel defect correction processing as shown in the remarks column of FIG. 4, pixel defect correction processing is performed (applied) with reference to an adjacent pixel adjacent to the defective pixel, and further outside the adjacent pixel. In some cases, pixel defect correction processing is performed with reference to adjacent pixels (neighboring pixels in this embodiment).

The table of FIG. 4 shows a tendency that the defective pixel correction process is performed by increasing the reference range in which surrounding pixels of the defective pixel are referred to in the use environment where the environmental temperature is low.
That is, as the reference data in FIG. 4, when the environmental temperature increases, the filtering process tends to be turned on from OFF. Further, when the environmental temperature increases, the size of the spatial filter tends to be reduced.
Further, when the environmental temperature increases, the suppression processing for the chroma signal tends to be turned from OFF to ON as the filtering processing. On the other hand, regarding the pixel defect correction processing, when the environmental temperature increases, the pixel defect correction processing tends to be turned from ON to OFF.

The endoscope apparatus 1 of the present embodiment having such a configuration is provided at the distal end portion 5 of the insertion portion 2 and images an optical image of the subject using a pair of objective optical systems 7a and 7b having parallax. An image sensor 8; an image sensor driver 13 for driving the image sensor 8; and a video signal processor 14 for converting a signal of a captured image photoelectrically converted by the image sensor 8 into a video signal. .
Further, the endoscope apparatus 1 performs image processing on the image of the video signal generated by the video signal processing unit 14, and generates a pair of measurement images based on the pair of objective optical systems 7a and 7b. An image processing unit 15 (including the first image processing unit 16), a measurement unit 18 that performs measurement on a subject using the pair of measurement images generated by the image processing unit 15, and the image processing An image processing selection unit 19 for instructing the processing content of the image processing unit 15 to the unit 15, and a storage unit 20 for storing reference data serving as a reference for determining the processing content of the image processing unit 15. .

  The reference data defines one of a plurality of processing contents for at least one of filtering processing and pixel defect correction processing for reducing noise as the image processing according to a use environment in which measurement by the measurement unit 18 is performed. The image processing selection unit 19 refers to the reference data stored in the storage unit 20, and makes a plurality of the image processing unit 15 to the image processing unit 15 according to the use environment. One of the processing contents is selected and instructed, and the image processing unit 15 is based on a selection instruction from the image processing selecting unit 19 and includes at least one of the filtering process and the pixel defect correction process. The pair of measurement images used for measurement by the measurement unit 18 is generated by image processing according to one.

Next, the operation of this embodiment according to FIG. 4 will be described with reference to FIGS. As described above, when the measurement instruction is given by the user, the image processing selection unit 19 acquires the detected temperature T detected by the temperature sensor 21 in order to recognize the temperature environment that forms the use environment at the time of the instruction. To do. Then, the image processing selection unit 19 selects ON / OFF as the processing content of the filtering process according to the reference data according to the environmental temperature corresponding to the detected temperature T.
As shown in step S1 of FIG. 5, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) at which the filtering process is turned ON / OFF. If the detected temperature T is equal to or higher than the predetermined temperature X3, the image processing selection unit 19 selects processing contents for turning on the filtering processing as shown in step S2. Then, the image processing selection unit 19 instructs this selection to the filtering processing circuit 31a of the first image processing unit 16.

On the other hand, if the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 selects processing contents for turning off the filtering processing as shown in step S3. Then, the image processing selection unit 19 instructs this selection to the filtering processing circuit 31a of the first image processing unit 16. The filtering processing circuit 31a of the first image processing unit 16 performs a filtering process with the processing content corresponding to the instruction, and generates a measurement image. In this way, the process of FIG.
When the temperature is low, the influence of noise such as the fixed pattern is small. Therefore, in this embodiment, when the temperature is low according to the table of FIG. Process. Thereby, measurement can be performed with high accuracy.

On the other hand, since the noise such as the fixed pattern increases as the temperature increases, the filtering process is switched from OFF to ON when the temperature is equal to or higher than the predetermined temperature based on the reference data accumulated in advance. Thereby, measurement can be performed with high accuracy. When the filtering process is turned on, the first image processing unit is selected by selecting the processing contents such as the strength of the filtering process, the size of the spatial filter, and the chroma suppress as shown in FIGS. 16 filtering processing circuits 31a are instructed.
By performing ON / OFF of the filtering process according to the procedure of FIG. 5, it is possible to prevent the measurement accuracy using the measurement image from being deteriorated.
When the filtering process is turned on, as shown in step S6 of FIG. 6, the image processing selection unit 19 further detects the detected temperature T equal to or higher than a threshold temperature (in this case, a predetermined temperature X4) that changes the intensity of the filtering process. It is determined whether or not.

When it is determined that the detected temperature T is equal to or higher than the predetermined temperature X4, the image processing selection unit 19 selects the filtering processing intensity to be level L4 as shown in step S7. Then, the image processing selection unit 19 instructs this selection to the filtering processing circuit 31a of the first image processing unit 16.
On the other hand, if the detected temperature T is lower than the predetermined temperature X4, the image processing selection unit 19 selects the level of filtering processing to be level L3 as shown in step S8. Then, the image processing selection unit 19 instructs this selection to the filtering processing circuit 31a of the first image processing unit 16. The filtering processing circuit 31a of the first image processing unit 16 performs a filtering process with the processing content corresponding to the instruction, and generates a measurement image. In this way, the process of FIG.

As described above, when the temperature becomes high, deterioration of measurement accuracy can be prevented by turning on the filtering process. Further, even when the filtering process is turned on, by further changing the strength of the filtering process as shown in FIG. 6, it is possible to prevent the measurement accuracy from being deteriorated as compared with the case where the filtering process is not changed.
Specifically, when the temperature becomes high, deterioration of measurement accuracy can be prevented by increasing (increasing) the strength of the filtering process.
FIG. 7 shows an operation of selecting the size of the spatial filter when the image processing selection unit 19 performs the filtering process according to the detected temperature T. In the following, description of the operation for instructing the first image processing unit 16 and the operation for generating the measurement image corresponding to the instruction by the first image processing unit 16 will be omitted.

As shown in step S11, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) for changing the size of the spatial filter. If the detected temperature T is equal to or higher than the predetermined temperature X3, the image processing selection unit 19 selects the processing content that employs the B × B spatial filter, as shown in step S12.
On the other hand, if the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 selects the processing content that employs the A × A spatial filter, as shown in step S13. Then, the process of FIG. 7 ends.
As described above, when the temperature becomes high, deterioration of measurement accuracy can be prevented by turning on the filtering process. Even in the state where the filtering process is turned on, by further changing the size of the spatial filter when the filtering process is performed as shown in FIG.

Specifically, when the temperature becomes high, the measurement accuracy can be prevented from deteriorating by reducing the size of the spatial filter.
Further, as shown in step S16 of FIG. 8, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) for turning on / off the filtering processing of chroma suppress. . If the detected temperature T is equal to or higher than the predetermined temperature X3, the image processing selection unit 19 selects the processing content for turning on the chroma suppression filtering processing as shown in step S17.
On the other hand, if the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 selects the processing content for turning off the filtering processing of the chroma suppress as shown in step S18. Then, the process of FIG. 8 ends.

As described above, when the temperature is high, the chroma suppression is turned on as shown in FIG. 8 in order to prevent deterioration in measurement accuracy due to noise mixed in the chroma signal. Degradation of measurement accuracy can be prevented.
Further, as shown in step S21 of FIG. 9, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) with / without pixel defect correction processing (ON / OFF). Determine. If the detected temperature T is equal to or higher than the predetermined temperature X3, as shown in step S22, the image processing selection unit 19 selects the processing content for which no pixel defect correction processing is performed (OFF).
On the other hand, if the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 selects the processing content to be set to the pixel defect correction processing present (ON) as shown in step S23. Then, the process of FIG. 9 ends.

When the temperature rises, the amount of noise superimposed on the pixel signal increases. Therefore, when there is a pixel defect correction process, the defective pixel is corrected based on the luminance value and color value of its surrounding pixels. Therefore, the increased noise component is also superimposed together. For this reason, the accuracy of detection of the corresponding position decreases. For this reason, the accuracy of measurement can be prevented from deteriorating by eliminating the pixel defect correction processing above the threshold temperature.
In addition, when the pixel defect correction process is performed, as illustrated in step S26 in FIG. 10, the image processing selection unit 19 further detects the threshold temperature at which the detected temperature T changes the correction reference range of the pixel defect correction process (in this case, It is determined whether or not the temperature is equal to or higher than a predetermined temperature X2). When it is determined that the detected temperature T is equal to or higher than the predetermined temperature X2, as illustrated in step S27, the image processing selection unit 19 selects the processing content to be corrected for the defective pixel using the adjacent pixel of the defective pixel.

On the other hand, if the detected temperature T is lower than the predetermined temperature X2, as shown in step S28, the image processing selection unit 19 selects the processing content to be corrected for the defective pixel using the adjacent pixel and the neighboring pixel of the defective pixel. Then, the process of FIG.
When the pixel defect correction processing is performed, deterioration of measurement accuracy can be prevented by selecting a correction reference range around the defective pixel when the defective pixel is corrected according to the temperature.
According to this embodiment that operates as described above, ON / OFF of filtering processing or pixel defect correction processing is selected according to the reference data stored in advance in the storage unit 20 according to the use environment, and image processing is performed according to the selection. Since measurement of distance, area, or the like is performed using the measurement image, highly accurate measurement can be performed. Therefore, according to the present embodiment, even when the usage environment changes, it is possible to perform measurement with reduced or prevented accuracy degradation according to the usage environment.
Although typical processing is shown in FIG. 5 to FIG. 10, processing in which filtering processing and pixel defect correction processing are combined may be performed.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 11 shows an endoscope apparatus 1B according to the second embodiment of the present invention, and the configuration of the main body 3B is partially different from that in FIG.
In the first embodiment described above, the measurement data accumulated in the past is classified so that measurement can be performed with high accuracy, and the processing contents can be determined (defined) according to each environmental temperature as a table as reference data. It has become. By adopting the processing content according to the reference data, it is possible to prevent a decrease or deterioration in measurement accuracy in many cases according to a change in the environmental temperature as a use environment.
On the other hand, when the user changes the processing contents for the subject to be actually measured, the user grasps the influence of noise from the deviation amount (difference amount) of the measurement result due to the change of the processing contents, and responds to the deviation amount. In some cases, it may be desired to set a measurement image. Alternatively, for example, when the temperature is high and it is easily affected by noise, the user may desire to actually perform measurement by changing the processing content and set a measurement image according to the measurement result. .

Alternatively, in the vicinity of the temperature at which the processing content changes as the reference data, the processing content changes due to a slight temperature difference, so the reference data is corrected according to the imaging conditions (imaging environment) of the subject as the actual measurement object. There is a possibility that it can be measured more accurately.
Moreover, there is a possibility that it corresponds to a use environment that does not apply to data accumulated in the past.
In order to cope with such a case, in this embodiment, a plurality of provisional measurement images (referred to as measurement evaluation images) generated with different processing contents are generated as described below, and each is used. A function is provided for actually measuring and determining a pair of measurement images to be used for actual measurement according to the measurement result.

In this embodiment, in the first embodiment, the first image processing unit 16 can further generate two pairs of measurement evaluation images having different processing contents, and the measurement unit 18 uses two pairs of measurement evaluation images. To obtain two measurement results for the same measurement instruction. Then, based on the two measurement results, for example, from the two pairs of measurement evaluation images according to the comparison result between the difference amount between the two measurement results and the set range, the measurement image that is actually used for measurement by the measurement unit 18 The function to determine
The endoscope apparatus 1B according to the present embodiment is the same as the endoscope apparatus 1 shown in FIG. 1 except that the user performs measurement from the first measurement instruction for performing the measurement instruction of the first embodiment from the measurement instruction unit 24 and the measurement evaluation image. A second measurement instruction for determining a use image and giving a measurement instruction can be performed.

Since the operation in the case of the first measurement instruction is the same as that of the first embodiment, the case of the second measurement instruction will be described below.
As the second measurement instruction, the user gives an instruction to generate two pairs of measurement evaluation images according to two different process contents from a plurality of process contents in one image process in the filtering process or the pixel defect correction process.
In response to the second measurement instruction, the image processing selection unit 19 instructs the first image processing unit 16 of two different processing contents in the instructed image processing, and the first image processing unit 16 2 pairs of measurement evaluation images are generated and output to the measurement unit 18. That is, the first image processing unit 16 includes a measurement evaluation image generation unit 40 that generates two pairs of measurement evaluation images.

In response to the second measurement instruction, the measurement unit 18 performs the same measurement using the two pairs of measurement evaluation images, and provides two measurement results in the case where each measurement is performed in the main body 3B. The result is output to the measurement result comparison unit 41.
As described above, in the present embodiment, the main body 3 </ b> B includes the measurement result comparison unit 41 that compares two measurement results output from the measurement unit 18. When comparing two measurement results, the measurement result comparison unit 41 calculates, for example, a difference amount between the two measurement results, and determines whether or not the difference amount is within a preset setting range.
For example, if the processing content is changed, the absolute value of the difference amount may increase due to noise, and image processing is basically performed when it is within the set range as the allowable range threshold. Alternatively, a measurement image is generated with processing contents close to this.

On the other hand, if the difference amount (absolute value) deviates from the setting range, it is considered that the influence of noise is large. Therefore, an image for measurement is generated without image processing or with weaker processing content. To do.
The main body 3B has a storage unit 42 for storing data of the setting range, and the measurement result comparison unit 41 refers to the data of the setting range to determine whether or not the difference amount of the measurement result is within the setting range. judge. Note that the storage unit 20 may store data of the setting range. In addition, the measurement result comparison unit 41 may determine whether or not the difference value is within a setting range allowed by noise by comparing whether or not the absolute value of the difference value is within a positive setting value. good.
The measurement result comparison unit 41 selects and determines a pair of measurement images actually used for measurement from two pairs of measurement evaluation images according to the comparison result between the difference amount and the set range. 43. Other configurations are the same as those of the first embodiment.

Next, the operation of this embodiment will be specifically described with reference to FIG. In FIG. 12, when the user as the use environment is, for example, when the detected temperature T is equal to or higher than the predetermined temperature X3, the second measurement instruction is performed so as to select (determine) the measurement image by turning on / off the filtering process. The processing procedure is shown.
In the first step S31, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) at which the filtering process is turned ON / OFF. If the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 refers to the reference data in the storage unit 20 and selects the processing content for turning off the filtering processing, as shown in step S32.

On the other hand, when the detected temperature T is equal to or higher than the predetermined temperature X3, the image processing selection unit 19 determines the processing contents when the filtering process is turned on and when the filtering process is turned off (two pairs of measurement evaluations) as shown in step S33. And select the processing contents corresponding to this selection to the filtering processing circuit 31a of the first image processing unit 16.
As shown in step S <b> 34, the first image processing unit 16 (the filtering processing circuit 31 a) generates two pairs of measurement evaluation images corresponding to the instructions and outputs them to the measurement unit 18.
As shown in step S <b> 35, the measurement unit 18 performs the same measurement using the two pairs of measurement evaluation images, acquires two measurement results, and outputs them to the measurement result comparison unit 41.

As shown in step S36, the measurement result comparison unit 41 performs a comparison process on the two measurement results. The measurement result comparison unit 41 calculates, for example, a difference amount between two measurement results in order to perform a comparison process on the two measurement results. Then, as shown in step S <b> 37, a comparison is made as to whether or not the amount of difference between the measurement results of the 41 measurement result comparison units 41 is within the set range.
In the case of a comparison result in which the difference amount is within the set range, as shown in step S38, the measurement result comparison unit 41 selects a pair of measurement evaluation images when the filtering process is ON as a pair of measurement images ( Setting).
On the other hand, in the case of a comparison result in which the difference amount does not fall within the set range and deviates from the set range, as shown in step S39, the measurement result comparison unit 41 sets a pair of measurement evaluation images when the filtering process is OFFN. Is selected (set) as a pair of measurement images.

Thus, the measurement unit 18 selects (sets) a pair of measurement images that are actually used for measurement from the two pairs of measurement evaluation images depending on whether or not the measurement result is within the setting range, and selects Measurement is executed using the paired measurement images.
As described above, in this embodiment, the processing contents are different, that is, two pairs of measurement evaluation images that are turned on and off are generated, and each measurement is actually performed in an actual use environment, and based on the measurement result. Therefore, even when the usage environment changes, it is possible to set an appropriate pair of measurement images according to the usage environment and prevent deterioration in accuracy. It becomes possible to do.
In addition, for temperature environments that are easily affected by noise, near temperatures where processing contents change, and usage environments that do not apply to past accumulated data, it is necessary to perform appropriate pairs of measurements according to the usage environment. It is possible to set an image and perform measurement while preventing deterioration in accuracy.

FIG. 13 shows a process when the user gives a second measurement instruction to select (determine) a measurement image with / without pixel defect correction processing, for example, when the detected temperature T is equal to or higher than the predetermined temperature X3. Show the procedure.
In first step S41, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X3) at which pixel defect correction processing is performed / not performed. If the detected temperature T is lower than the predetermined temperature X3, the image processing selection unit 19 refers to the reference data in the storage unit 20 as shown in step S42, and selects the processing content to be subjected to the pixel defect correction processing. Note that the processing corresponding to step S42 may be performed (particularly when the detected temperature is lower than a predetermined temperature different from the predetermined temperature X3) according to a user's selective instruction.

On the other hand, if the detected temperature T is equal to or higher than the predetermined temperature X3, as shown in step S43, the image processing selection unit 19 performs two types of processing contents with and without pixel defect correction processing (two pairs). To generate a measurement evaluation image). The image processing selection unit 19 instructs the processing content corresponding to this selection to the pixel defect correction processing circuit 32a of the first image processing unit 16 (which forms the measurement evaluation image generation unit 40).
As shown in step S <b> 44, the first image processing unit 16 (the pixel defect correction processing circuit 32 a) generates two pairs of measurement evaluation images corresponding to the instructions and outputs them to the measurement unit 18.
As shown in step S <b> 45, the measurement unit 18 performs the same measurement using two pairs of measurement evaluation images, acquires two measurement results, and outputs the two measurement results to the measurement result comparison unit 41.

As shown in step S46, the measurement result comparison unit 41 performs a comparison process on the two measurement results. The measurement result comparison unit 41 calculates, for example, a difference amount between two measurement results in order to perform a comparison process on the two measurement results. Then, as shown in step S47, the measurement result comparison unit 41 compares whether or not the difference amount between the two measurement results is within the set range.
In the case of the comparison result in which the difference amount is within the set range, as shown in step S48, the measurement result comparison unit 41 uses the pair of measurement evaluation images when the pixel defect correction processing is performed as the pair of measurement images. Select (set).
On the other hand, in the case of a comparison result in which the difference amount does not fall within the set range and deviates from the set range, as shown in step S49, the measurement result comparison unit 41 is for measurement evaluation of a pair without pixel defect correction processing. The image is selected (set) as a pair of measurement images.

Thus, the measurement unit 18 selects (sets) a pair of measurement images that are actually used for measurement from the two pairs of measurement evaluation images depending on whether or not the measurement result is within the setting range, and selects Measurement is executed using the paired measurement images.
As described above, in this embodiment, the processing contents are different, that is, two pairs of measurement evaluation images with and without pixel defect correction processing are generated, and each measurement is actually performed in an actual use environment, and the measurement result is obtained. Since the measurement images for the pair are set based on this, even when the usage environment changes, an appropriate pair of measurement images can be set according to the usage environment, preventing deterioration of accuracy. Measurement can be performed.
In addition, even in a temperature environment that is easily affected by noise, in the vicinity of a temperature at which the content of processing changes, or in a usage environment that does not apply to past accumulated data, accuracy deterioration was prevented according to the usage environment. Measurement can be performed.

  FIG. 14 shows a case where the user selects a measurement image when the pixel defect correction processing is corrected from an adjacent pixel and when correction is performed from an adjacent pixel and a neighboring pixel, for example, when the detected temperature T is equal to or higher than a predetermined temperature X2. A processing procedure in the case where the second measurement instruction is performed as shown in FIG. In the first step S51, the image processing selection unit 19 determines whether or not the detected temperature T is equal to or higher than a threshold temperature (in this case, a predetermined temperature X2) corrected by the adjacent pixels. If the detected temperature T is lower than the predetermined temperature X2, as shown in step S52, the image processing selection unit 19 refers to the reference data in the storage unit 20 and performs pixel defect correction processing using adjacent pixels and neighboring pixels. Select the process to be performed.

On the other hand, when the detected temperature T is equal to or higher than the predetermined temperature X2, as shown in step S53, the image processing selection unit 19 performs pixel defect correction processing using correction using adjacent pixels and neighboring pixels, and correction using only adjacent pixels. Are selected (in order to generate two pairs of measurement evaluation images). The image processing selection unit 19 instructs the processing content corresponding to this selection to the pixel defect correction processing circuit 32 a of the first image processing unit 16.
As shown in step S <b> 54, the first image processing unit 16 (the pixel defect correction processing circuit 32 a) generates two pairs of measurement evaluation images corresponding to the instructions and outputs them to the measurement unit 18.
As shown in step S <b> 55, the measurement unit 18 performs the same measurement using the two pairs of measurement evaluation images, acquires the two measurement results, and sends the difference between the two measurement results to the measurement result comparison unit 41. Output.

As shown in step S56, the measurement result comparison unit 41 performs a comparison process on the two measurement results. The measurement result comparison unit 41 calculates, for example, a difference amount between two measurement results in order to perform a comparison process on the two measurement results. Then, as shown in step S57, the measurement result comparison unit 41 compares whether or not the difference amount between the two measurement results is within the set range.
In the case of the comparison result in which the difference amount is within the set range, as shown in step S58, the measurement result comparison unit 41 measures the pair of measurement evaluation images when the correction is performed using the adjacent pixel and the neighboring pixel. Select (set) as an image.
On the other hand, in the case of a comparison result in which the difference amount does not fall within the set range and deviates from the set range, as shown in step S59, the measurement result comparison unit 41 performs pair measurement when correction is performed using only adjacent pixels. The evaluation image is selected (set) as a pair of measurement images.

Thus, the measurement unit 18 selects (sets) a pair of measurement images that are actually used for measurement from the two pairs of measurement evaluation images depending on whether or not the measurement result is within the setting range, and selects Measurement is executed using the paired measurement images.
Therefore, according to the present embodiment, two pairs of measurement evaluation images having different processing contents are generated, each measurement is actually performed in an actual use environment, and a pair of measurement images is set based on the measurement result. Therefore, even when the usage environment changes, an appropriate pair of measurement images can be set according to the usage environment, and measurement with reduced or prevented deterioration in accuracy can be performed. . In addition, the present embodiment also has the same effect as the first embodiment.

In the present embodiment, typical processing has been described with reference to FIGS. 12 to 14, but processing other than that illustrated in FIGS. 12 to 14 can also be performed. For example, in the case of FIG. 12, processing similar to FIG. 12 may be performed depending on whether the detected temperature T is equal to or higher than the predetermined temperature X4 instead of the predetermined temperature X3.
In this case, when the detected temperature T is lower than the predetermined temperature X4, as the processing corresponding to step S32, the image processing selection unit 19 sets the processing content to turn on the filtering processing at a level where the filtering processing strength is low. select.
On the other hand, when the detected temperature T is equal to or higher than the predetermined temperature X4, as a process corresponding to step S33, the image processing selection unit 19 turns on the filtering process and turns off the filtering process at a level where the strength of the filtering process is small. Two types of processing contents may be selected, and the processing after step S34 may be performed.

Further, the combination processing of FIG. 12 and FIG. 13 or FIG. 14 may be performed. In the above description, two pairs of measurement evaluation images having different processing contents are generated. However, the present invention is not limited to the case of generating a pair of measurement evaluation images. A plurality of pairs of measurement evaluation images including a pair or more cases may be generated, and a pair of measurement images actually used in the use environment may be set according to a plurality of measurement result values. Even when three or more pairs of measurement evaluation images are generated, conditions to be used as a pair of measurement images may be determined in advance according to the amount of deviation of three or more measurement results.
Note that embodiments configured by partially combining the above-described embodiments and the like also belong to the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Endoscope apparatus, 2 ... Insertion part, 3 ... Main-body part, 4 ... Image display apparatus, 5 ... Tip part, 6 ... LED, 7a, 7b ... Objective optical system, 8 ... Imaging element, 14 ... Video signal processing 15, image processing unit, 16, first image processing unit, 17, second image processing unit, 18, measurement unit, 19, image processing selection unit, 20, 42, storage unit, 21, temperature sensor, 23,. Temperature detection unit, 24 ... measurement instruction unit, 31a and 31b ... filtering processing circuit, 32a and 32b ... pixel defect correction processing circuit, 40 ... measurement evaluation image generation unit, 41 ... measurement result comparison unit, 43 ... measurement image selection unit

Japanese Patent Laid-Open No. 10-248806

Claims (5)

An image sensor that is provided at the distal end of the insertion unit and captures an optical image of the subject using a pair of objective optical systems having parallax;
A video signal processing unit that converts a signal of a captured image photoelectrically converted by the imaging element into a video signal;
An image processing unit that performs image processing on an image of the video signal generated by the video signal processing unit, and generates a pair of measurement images based on the pair of objective optical systems;
Using the pair of measurement images generated by the image processing unit, a measurement unit that performs measurement on a subject;
An image processing selection unit for instructing the image processing unit to process the image processing;
A storage unit that stores reference data serving as a reference in determining the processing content of the image processing;
Have
The reference data defines one of a plurality of processing contents for at least one of filtering processing and pixel defect correction processing for reducing noise as the image processing according to a use environment in which measurement by the measurement unit is performed. Yes,
The image processing selection unit refers to the reference data stored in the storage unit, and instructs the image processing unit to select one of a plurality of processing contents of the image processing according to the use environment. ,
Based on the selection instruction from the image processing selection unit, the image processing unit performs measurement by image processing according to one of a plurality of processing contents for at least one of the filtering processing and the pixel defect correction processing. An endoscope apparatus, characterized in that the pair of measurement images to be used for the generation is generated. The image processing unit further generates two pairs of measurement evaluation images when the image processing is not performed on the image of the video signal and when the image processing is performed. It has an image generation unit for measurement evaluation,
The measurement unit calculates two measurement results using the two pairs of measurement evaluation images generated by the image processing unit in response to the same measurement instruction for the subject,
Furthermore, it has a measurement result comparison part which compares whether two measurement results by the said measurement part are in the preset setting range, and the comparison result by the said measurement result comparison part deviates from the said setting range. If the image processing unit does not perform image processing among the two pairs of measurement evaluation images generated by the image processing unit,
On the other hand, when the comparison result is within the set range, a pair of measurement evaluation images when the image processing generated by the image processing unit is performed is selected as the pair of measurement images. The endoscope apparatus described in 1. When the environmental temperature measured by the measurement unit as the use environment is less than a predetermined temperature, the image processing unit does not perform the filtering process with reference to the reference data for the image of the video signal, or Generating a pair of measurement images with reduced strength of the filtering process;
On the other hand, when the environmental temperature is equal to or higher than a predetermined temperature, the image processing unit further performs two pairs of measurements when the filtering process is performed on the image of the video signal and when the filtering process is not performed. It has an image generation unit for measurement evaluation that generates an image for evaluation,
The measurement unit calculates two measurement results using the two pairs of measurement evaluation images generated by the image processing unit in response to the same measurement instruction for the subject,
Furthermore, it has a measurement result comparison part which compares whether two measurement results by the said measurement part are in the preset setting range, and the comparison result by the said measurement result comparison part deviates from the said setting range. If there is, the pair of measurement evaluation images when the filtering process is not performed among the two pairs of measurement evaluation images is selected as the measurement target image used for measurement by the measurement unit. The endoscope apparatus according to claim 1. When the environment temperature measured by the measurement unit as the use environment is less than a predetermined temperature, the image processing unit performs the pixel defect correction processing with reference to the reference data for the image of the video signal, and Generate a pair of measurement images,
On the other hand, when the environmental temperature is equal to or higher than a predetermined temperature, the image processing unit further performs two pairs of pixel defect corrections for the image signal image when the pixel defect correction process is performed and when the pixel defect correction process is not performed. A measurement evaluation image generation unit for generating a measurement evaluation image;
The measurement unit calculates the same measurement for the subject, and calculates two measurement results using the two pairs of pixel defect correction measurement evaluation images created by the image processing unit,
Furthermore, it has a measurement result comparison part which compares whether two measurement results by the said measurement part are in the preset setting range, and the comparison result by the said measurement result comparison part deviates from the said setting range. The measurement unit uses the pair of pixel defect correction measurement evaluation images for measurement when the pixel defect correction processing is not performed, of the two pairs of pixel defect correction measurement evaluation images. The endoscope apparatus according to claim 1, wherein the endoscope apparatus is selected as a target image. When the environmental temperature measured by the measurement unit as the use environment is less than a predetermined temperature, the image processing unit for the image of the video signal refers to the reference data and the adjacent pixel adjacent to the defective pixel and the pixel Generate the pair of measurement images by performing the pixel defect correction processing for correcting the defective pixels from neighboring pixels adjacent to the outside of the adjacent pixels,
On the other hand, when the environmental temperature is equal to or higher than a predetermined temperature, the image processing unit further applies the pixel defect correction processing from an adjacent pixel and a neighboring pixel adjacent to the defective pixel to the image of the video signal, A measurement evaluation image generation unit that generates two pairs of pixel defect correction measurement evaluation images when performing the pixel defect correction processing from adjacent pixels adjacent to the defective pixels;
The measurement unit calculates the same measurement for the subject, and calculates two measurement results using the two pairs of pixel defect correction measurement evaluation images created by the image processing unit,
Furthermore, it has a measurement result comparison part which compares whether two measurement results by the said measurement part are in the preset setting range, and the comparison result by the said measurement result comparison part deviates from the said setting range. If the pixel defect correction measurement evaluation image for the pixel defect correction is performed from the adjacent pixels of the defective pixel, the measurement evaluation image for the pixel defect correction pair of the two pairs of pixel defect correction measurement evaluation images is measured. The endoscope apparatus according to claim 1, wherein the unit selects the measurement target image used for measurement.

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