JP2967830B2 - Endoscope color shift detection device and color shift correction device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an endoscope pixel composed of a plurality of color images obtained in time series by an endoscope apparatus using a frame sequential method. The present invention relates to an endoscope color misregistration detection device that detects a color misregistration and an endoscope color misregistration correction device that corrects a color misregistration of an endoscope image.

[Prior art] In recent years, by inserting an elongated insertion portion into a body cavity,
2. Description of the Related Art Endoscopes capable of observing organs in a body cavity and the like and performing various treatments using a treatment tool inserted into a treatment tool channel as necessary are widely used.

Also, various electronic endoscopes using a solid-state imaging device such as a charge-coupled device (CCD) as an imaging unit have been proposed.

By the way, in an endoscope that performs imaging in a frame-sequential manner, since color separation is performed in a time-series manner, when a subject moves quickly, for example, the position of each image corresponding to each color is shifted, and primary colors and the like appear. That is, a so-called color shift occurs.

To cope with this, Japanese Patent Application Laid-Open No. Sho 62-145529 discloses that a still image is divided into a plurality of regions and each image is moved or moved so that the correlation value between the RGB images constituting each region is maximized. An apparatus that corrects an image having a color shift to an image having no color shift by performing an interpolation process is disclosed. Also, JP-A-63-1091
Japanese Patent Publication No. 87 discloses an image still unit, a unit for recording a plurality of frame or field images, and the most color shift among a plurality of frame or field images which are stopped by the image still unit and recorded on the recording unit. An apparatus is disclosed which includes a detecting unit for detecting an image with a small amount, and selectively displays an image with the least amount of color shift based on the detecting unit of the detecting unit.

[Problems to be Solved by the Invention] However, in the device disclosed in Japanese Patent Application Laid-Open No. Sho 62-145529, correction is performed based on the correlation between a set of RGB images. Good between good GB images, but bad R images with poor A / P and other GB images
At the time of correction between images, the color shift does not always become the minimum when the correlation value becomes the maximum, and satisfactory correction was not performed.

Further, the apparatus disclosed in Japanese Patent Application Laid-Open No. 63-109187 has a problem that the circuit scale is increased because a plurality of image memories are required.

In view of the above problems, an object of the present invention is to provide a color shift detecting device for an endoscope having a small circuit scale.

Another object of the present invention is to provide a color shift correction device for an endoscope which has a small circuit scale and can perform good color shift correction.

[Means for Solving the Problems] A color shift detecting apparatus for an endoscope according to claim 1 inputs a plurality of color image signals obtained by performing frame sequential imaging, and outputs a saturation signal and a hue signal. Color signal converting means, primary color part specifying means for specifying a primary color part in a predetermined coordinate system based on the saturation signal and the hue signal, and a color based on the color signal in the primary color part specified in the coordinate system. A color shift detecting means for detecting occurrence of a shift.

In addition, the color shift correction device for an endoscope according to claim 2 is a color signal conversion unit that inputs an image signal of a plurality of colors obtained by performing frame sequential imaging and outputs a saturation signal and a hue signal, Primary color portion specifying means for specifying a primary color portion in a predetermined coordinate system based on a saturation signal and the hue signal; and color shift detection for detecting a color shift based on each signal in the primary color portion specified in the coordinate system. Means, and a control circuit capable of controlling the plurality of color image signals so as to shift a specific image with respect to a reference image among the plurality of color images obtained from the plurality of color image signals. It is characterized by.

In addition, the color shift correction device for an endoscope according to claim 3 is a color signal conversion unit that inputs an image signal of a plurality of colors obtained by performing frame sequential imaging and outputs a saturation signal and a hue signal, Primary color portion specifying means for specifying a primary color portion in a predetermined coordinate system based on a saturation signal and the hue signal; and color shift detection for detecting a color shift based on the color signal in the primary color portion specified in the coordinate system. Means, a color misregistration amount detecting means for detecting a color misregistration amount based on a color misregistration detection result by the color misregistration detecting means, and a reference image among a plurality of color images obtained from the plurality of color image signals. And a control circuit capable of controlling the image signals of the plurality of colors so as to shift the specific image by shifting the specific image by the control circuit. Shift amount that minimizes the amount A detecting means for detecting that, based on the shift amount detected by the detection means, and having and an image reconstruction means for reconstructing an image from said plurality of colors image signals.

According to the first aspect of the present invention, the image signals of a plurality of colors obtained by image-sequential imaging are converted into a saturation signal and a hue signal, and specified in a predetermined coordinate system based on the saturation signal and the hue signal. The occurrence of a color shift is detected from the color signal appearing in the primary color portion.

According to the second aspect of the present invention, the image signals of a plurality of colors obtained by image-sequential imaging are converted into a saturation signal and a hue signal, and specified in a predetermined coordinate system based on the saturation signal and the hue signal. The occurrence of color misregistration is detected from the color signal appearing in the primary color portion, and the color misregistration is corrected by shifting a specific image with respect to a reference image among the plurality of color images.

According to the third aspect of the present invention, the image signals of a plurality of colors obtained by image-sequential imaging are converted into a saturation signal and a hue signal, and specified in a predetermined coordinate system based on the saturation signal and the hue signal. The color misregistration amount is detected from the color signal appearing in the primary color portion, and based on the color misregistration amount, among the plurality of color images,
The color shift is corrected by shifting a specific image with respect to a reference image.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

1 to 5 relate to a first embodiment of the present invention, FIG. 1 is a block diagram showing a configuration of a color misregistration correction device, FIG. 2 is a block diagram showing a configuration of an endoscope device, and FIG. FIG. 4A is a side view showing the entire endoscope apparatus, FIG. 4A is an explanatory view showing a color distribution on a color difference plane of an endoscope image having no color shift, and FIG. Fig. 5A is an explanatory diagram showing a color distribution of an endoscope image having a color shift on a color difference plane, Fig. 5A is an explanatory diagram showing a matching area of a G image, and Figs.
FIG. 2B is an explanatory diagram showing a matching area and a scan area of the R or B image.

As shown in FIG. 3, the endoscope apparatus according to the present embodiment includes an electronic endoscope 1. This electronic endoscope 1
It has an elongated and flexible insertion section 2, for example, and a large-diameter operation section 3 is connected to the rear end of the insertion section 2. The operation unit 3
A flexible universal cord 4 is extended laterally from a rear end of the cable, and a connector 5 is provided at a distal end of the universal cord 4. The electronic endoscope 1 is connected via the connector 5 to a video processor 6 having a light source device and a signal processing circuit built therein.
Further, a monitor 7 is connected to the video processor 6.

On the distal end side of the insertion portion 2, a rigid distal end portion 9 and a bending portion 10 which can be bent rearward adjacent to the distal end portion 9 are sequentially provided. The operating section 3 is provided with a bending operation knob 11, and by rotating the bending operation knob 11, the bending section 10 can be bent in the up / down / left / right directions. The operation section 3 has an insertion port communicating with a treatment instrument channel provided in the insertion section 2.
There are twelve.

As shown in FIG. 2, a light guide 14 for transmitting illumination light is inserted into the insertion section 2 of the electronic endoscope 1. The distal end surface of the light guide 14 is arranged at the distal end 9 of the insertion section 2 so that illumination light can be emitted from the distal end 9. The light guide 14 has an incident end inserted through the universal cord 4 and connected to the connector 5. Further, an objective lens system 15 is provided at the distal end portion 9, and a solid-state imaging device 16 is provided at an image forming position of the objective lens system 15. This solid-state imaging device 16
Has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region including the visible region. The solid-state imaging device 16 includes:
The signal lines 26 and 27 are connected, and these signal lines 26 and 27 are inserted through the insertion section 2 and the universal cord 4 and connected to the connector 5.

On the other hand, the video processor 6 is provided with a lamp 21 that emits light in a wide band from ultraviolet light to infrared light. As the lamp 21, a general xenon lamp, a strobe lamp, or the like can be used. The xenon lamp and the strobe lamp emit a large amount of ultraviolet light and infrared light as well as visible light. This lamp 21 is connected to a power supply 22
Is supplied with power.

A rotary filter 39 that is driven to rotate by a motor 23 is provided in front of the lamp 21. In the rotary filter 39, filters that transmit light in the respective wavelength regions of red (R), green (G), and blue (B) are arranged along the circumferential direction. The rotation of the motor 23 is controlled by a motor driver 25 to be driven.

The light that has passed through the rotary filter 39 and has been separated in time series into light in the R, G, and B wavelength regions is incident on the incident end of the light guide 14, and the distal end portion is transmitted through the light guide 14. 9 and is emitted from the tip 9 to illuminate the observation site.

The light from the observation site illuminated by this illumination light,
An image is formed on the solid-state imaging device 16 by the objective lens system 15 and photoelectrically converted. A drive pulse from a driver circuit 31 in the video processor 6 is applied to the solid-state imaging device 16 via the signal line 26,
Reading and transferring are performed by this drive pulse. The video signal read from the solid-state imaging device 16 is transmitted to the video processor 6 via a signal line 27.
The signal is input to a preamplifier 32 provided inside or inside the electronic endoscope 1. The video signal amplified by the preamplifier 32 is input to a process circuit 33, which performs signal processing such as γ correction and carrier removal, and has a knee characteristic for a halation portion. Then, a process is performed to apply a bias to the pedestal level to the dark part. The output of the process circuit 33 is converted into a digital signal by an A / D converter. The digital video signal is selected by a selector 35 into, for example, a memory (1) 36a, a memory (2) 36b, and a memory (3) 36c corresponding to each color of red (R), green (G), and blue (B). Is memorized. The memory (1) 36a, the memory (2)
The memory 36b and the memory (3) 36c are read at the same time, converted into analog signals by the D / A converter 37, and output as R, G, B color signals.

Further, a screen frame generating circuit 40 for generating a screen frame for display is provided, and a control signal from the screen frame generating circuit 40
A display frame is synthesized with the output image signal of the D / A converter 37 and output to the superimpose circuit 41. In the superimpose circuit 41, the patient information input by the character information input circuit 42 is superimposed on the image information. The image signal to which the display frame and the character information such as patient information are added in this manner is input to the TV monitor 46, the color misregistration correction device 100, and the matrix circuit 43 as R, G, and B signals. It has become so. And the TV monitor
The subject image is displayed in color at 46. In the matrix circuit 43, the R, G, B signals are converted into a color difference signal and a luminance signal.The color difference signal and the luminance signal are input to an encoder circuit 44, converted into an NTSC signal and output, and output to a VTR 45. It is to be recorded.

In the video processor 6, a timing generator 38 for generating the timing of the whole system is provided, and the timing generator 38 controls a cycle between respective circuits such as the motor driver 25, the driver circuit 31, the memories 36a, 36b and 36c. Has been taken.

By the way, when observing a color distribution in an endoscope image obtained by such a field sequential type endoscope apparatus on a color difference plane, in an endoscope image which does not cause a normal color shift, As shown in FIG. 4 (a), the range is limited to a narrow hue range centered on R. This is because hemoglobin largely determines the color tone of the mucous membrane of the living body during the observation of the living body with the endoscope. On the other hand, as shown in FIG. 4 (b), R, G, B
And its complementary colors cyan (Cy), magenta (Mg), and yellow (Ye). This is noticeable when observing a high-brightness and high-speed moving subject such as during water supply.
Further, it is remarkably observed when observing a part having a large contrast difference from the background, such as a stomach corner, or a part that moves at high speed due to pulsation, such as the esophagus. The color misregistration correction apparatus 100 according to the present embodiment uses the difference in characteristics on a color difference plane between an image in which color misregistration occurs and an image in which color misregistration does not occur in such a frame sequential method, and calculates the amount of color misregistration. To detect.

The color misregistration correction device 100 is configured as shown in FIG.

That is, the output from the superimpose circuit 41
RGB image signals are A / D converters 101, 102, 103, respectively.
Is converted into a digital image signal by the frame memory circuit.
One frame is recorded on each of 104, 105, and 106. Here, the reading from each of the frame memory circuits 104, 105, and 106 is controlled by the memory control circuit 107 as follows.

Since the movement of the object on the screen is not uniform, as shown in FIGS. 5 (a) and (b), for example, 100 detection points are provided in the image to perform local color shift detection.
A matching area for detecting a color shift is set around the detection point. In the G image serving as the reference image, as shown in FIG. 5A, the matching area is fixed. On the other hand, in the R and B images, the matching area is sequentially moved within the scan area centered on the detection point, as shown in FIG. 5 (b). The scan area is G
This is a range in which a matching area corresponding to the matching area of the image is searched.

The image in the matching area read by each frame memory circuit 104, 105, 106
The GB image signal is decoded into RY and GY color difference signals. This decoding circuit 108 is configured by a ROM table. The image signal converted into the color difference signal by the decoding circuit 108 is polar-coordinate-converted from the color difference signal to hue and saturation for displaying the color difference plane in polar coordinates by the polar coordinate conversion circuit 109 using a ROM table. That is, the decoding circuit 108 and the polar coordinate conversion circuit 109
Function as the color signal conversion means in the first to third aspects.

The saturation signal output from the polar coordinate conversion circuit 109 is
It is designed to be input to a saturation level detection circuit 110 for detecting a saturation level. This saturation level detection circuit 110
Thus, malfunction due to a wide range of hue components of the noise component is prevented. On the other hand, the hue data output from the polar coordinate conversion circuit 109 is
The image data having a saturation level equal to or higher than a certain value output from the saturation level detection circuit 110 and existing in the range of R, G, B, and Ye, Mg, and Cy is output for each pair of matching areas. To detect. That is, the primary color part detection circuit 111 is provided in the first embodiment.
4. A primary color portion specifying unit according to any one of claims 1 to 3, and a primary color portion specifying unit.
Function as a color misregistration detecting means.

The primary color portion, that is, the color shift portion detected by the primary color portion detection circuit 111 is input to the primary color area calculation circuit 112, and the primary color area, that is, the color shift amount for each matching area set is calculated. . That is, the primary color area calculation circuit 112 functions as the color misregistration amount detection circuit in claim 3. The calculated primary color area is input to the primary color area minimum value detection circuit 113. The primary color area minimum value detection circuit 113 detects the primary color area (color shift amount) of each of a plurality of sets of matching areas obtained by sequentially moving the matching areas of the R and B images in the scan area. The minimum value is detected, the minimum value is stored, and the shift amount of the matching area when the color shift amount becomes the minimum value is recorded in the shift map memory 114. That is, the primary color area minimum value detection circuit 113 functions as a detecting unit that detects a shift amount that minimizes the color shift amount in the claims. The shift map memory 114
Stores the shift amount, which is the position of the minimum color shift in the scan area of each matching area, for each matching area. Note that the memory control circuit 107 receives a matching area clear signal from the primary color part detection circuit 111 and the primary color area calculation circuit 112, and a scan area clear signal from the primary color area minimum value detection circuit 113 and the shift map memory 114. The matching area and the scan area are updated according to each signal. That is, the memory control circuit 107, the primary color part detection circuit 111, the primary color area calculation circuit 11
2, primary color area minimum value detection circuit 113, shift map memory 11
4 functions as a control circuit for shifting a specific image with respect to a reference image in claims 2 and 3 as a whole.

In this way, the relative positional relationship between the matching areas where the amount of color shift is minimized is obtained, and the image is reconstructed by the image reconstruction circuit 116 based on the positional relationship.
At this time, the interpolation processing circuit 115 performs interpolation processing between the respective matching areas. That is, the image reconstruction circuit 116 uses the R image and the B image read from the frame memory circuits 104 and 106 to shift the matching area so that the amount of color misregistration is minimized. An image is reconstructed based on the data obtained by interpolating the data of each of the matching areas. By performing this interpolation processing, the boundary between the matching areas is reconstructed without unnaturalness when reconstructing the image.

The reconstructed R and B images are recorded in the sub-frame memories 117 and 118 as image data for one frame of each color. Each sub-frame memory 117, 118
Is converted into an analog signal by the D / A converters 119 and 121 and output. On the other hand, the G image serving as the reference image is converted into an analog signal by the D / A converter 120 and output without performing image reconstruction processing.

As described above, in the color misregistration correction apparatus according to the present embodiment, the color misregistration is corrected so that the primary color area on the hue plane, that is, the color misregistration amount is minimized. The color misregistration correction error can be reduced, and more accurate color misregistration correction can be performed. Further, since a plurality of sets of RGB image memories are not required, the circuit scale is small and the configuration can be made easily.

FIG. 6 is a block diagram showing a configuration of a color misregistration correction apparatus according to a second embodiment of the present invention.

In the color misregistration correction device 100 of the present embodiment, the hue data output from the polar coordinate conversion circuit 109 of the first embodiment is
The data is input to a hue memory 201 that records hue data for one frame. This hue memory 201
The image data of one frame before is input to a primary color part detection circuit 202 instead of the primary color part detection circuit 111 in the first embodiment. Further, the current hue data output from the polar coordinate conversion circuit 109 is also input to the primary color portion detection circuit 202.

The primary color part detection circuit 202 compares the current hue data output from the polar coordinate conversion circuit 109 with the hue data of one frame before output from the hue memory 201, thereby obtaining R, G, B or Ye, By detecting each of the primary colors Cy and Mg on the color-difference plane and comparing it with the immediately preceding frame, it is possible to detect whether the hue has moved, that is, whether or not the subject being observed has moved. That is, the primary color part detection circuit 202
Only the primary color portion that has changed compared to that before the frame is output to primary color area detection section 112. Therefore, in the present embodiment, the color shift correction is performed only for the primary color portion having motion.

 Other configurations and operations are the same as those of the first embodiment.

According to the present embodiment, the same effect as that of the first embodiment can be obtained, and the primary color portion caused by dyeing by spraying a dye such as methylene blue and Congo red and the primary color portion caused by bleeding are erroneously recognized as color misregistration. Can be prevented, and more accurate color shift correction can be performed.

FIG. 7 is a block diagram showing a configuration of a color misregistration correction apparatus according to a third embodiment of the present invention.

In the color misregistration correction apparatus 100 according to the present embodiment, the area of the primary color portion due to the color misregistration of the observation image calculated by the primary color area calculation circuit 112 according to the second embodiment is equal to the primary color area minimum value detection circuit 113 according to the second embodiment. Primary color area minimum value detection circuit 3 instead of
01 is to be entered. The primary color area minimum value detection circuit 301 detects the shift amount of the matching area where the area of the primary color portion is the minimum and the minimum value of the area.

By the way, it is possible to correct the color misregistration by setting the scan area to a certain extent, even for a site where a lesion is likely to occur, such as a stomach corner, and where the movement amount of the subject is large. For a subject that is largely out of the scan area and hardly involved in the diagnosis, it is desired to make the observed image easier to see by reducing the color shift that is visually obstructive without correcting the RGB image. Therefore, in this embodiment, the primary color area minimum value detection circuit
The minimum value comparison circuit 302 detects whether the minimum value detected in 301 does not become smaller than a predetermined value. That is, the minimum value comparison circuit 302 compares the minimum value detected by the primary color area minimum value detection circuit 301 with a predetermined set value.

Further, a matching area average color calculation circuit 303 for calculating an average color in the matching area from the RGB image signals from the frame memory circuits 104, 105, and 106 is provided, and an output of the average color calculation circuit 303 and an output of the interpolation processing circuit 115 are provided. , To the selection circuit 304. The selection circuit 304 selects one of the output of the average color calculation circuit 303 and the output of the interpolation processing circuit 115 according to the output of the minimum value comparison circuit 302, and sends it to the screen reconstruction circuit 305. ing.

The minimum value comparison circuit 302 outputs a signal to the selection circuit 304 so as to select the output of the average color calculation circuit 303 for a portion where the compared minimum value is larger than the set value, that is, for a portion where the color shift is extremely large. I do. On the other hand, the minimum value comparison circuit 3
For the portion where the minimum value compared in 02 is equal to or smaller than the set value, the selection circuit 304 selects the image data on which the interpolation processing circuit 115 has corrected the color misregistration and performed the interpolation processing. The image data selected by the selection circuit 304 is output to the screen reconstruction circuit 305.
And the screen is reconstructed. Reconstructed R and B
The image is recorded as image data for one frame of each color in the sub-frame memories 117 and 118, and the image signal recorded in each of the sub-frame memories 117 and 118 is stored in the D / A converter 11
At 9,121, it is converted into an analog signal and output. On the other hand, the G image serving as the reference image is converted into an analog signal by the D / A converter 120 and output without performing screen reconstruction processing.

 Other configurations and operations are the same as those of the second embodiment.

According to the present embodiment, the same effects as those of the second embodiment can be obtained, and even for a subject that moves so fast that it cannot be corrected as in the case of water supply, the color shift that hinders visual observation is matched. This can be reduced by performing the masking process by replacing the average color in the area with the average color, and the observability can be improved in the frame sequential method.

If the average color cannot be sufficiently reduced in the matching area due to the color shift, the average color with the neighboring matching area is adopted to mask the color shift of the moving object at higher speed. Processing may be performed.

Note that the present invention is not limited to the above embodiments. For example, the detection of primary colors is not limited to processing on a color difference plane by RY and BY, but may be performed on a color plane such as a uv color plane and an XY color plane. , Or a process in another color space such as the XYZ or a ^* b ^* L ^* color space.

In addition, the endoscope to which the present invention is applied is a type having a solid-state image sensor at the tip, and a type in which an image is guided to the outside of an object to be observed via an image guide using an optical fiber and then imaged by the image sensor. Either is acceptable.

[Advantage of the Invention] According to the color shift detecting apparatus for an endoscope according to claim 1, the image signals of a plurality of colors obtained by performing frame sequential imaging are converted into a saturation signal and a hue signal. Based on the hue signal,
Since the occurrence of color misregistration is detected from the color signal appearing in the primary color portion specified in the predetermined coordinate system, the circuit scale can be reduced.

According to the second aspect of the present invention, the image signals of a plurality of colors obtained by image-sequential imaging are converted into a saturation signal and a hue signal, and specified in a predetermined coordinate system based on the saturation signal and the hue signal. Since the occurrence of color misregistration is detected from the color signal appearing in the primary color portion, and a specific image is shifted with respect to a reference image among the plurality of color images, the color misregistration is corrected. Can be reduced, and good color shift correction can be performed.

According to the third aspect of the present invention, the image signals of a plurality of colors obtained by image-sequential imaging are converted into a saturation signal and a hue signal, and specified in a predetermined coordinate system based on the saturation signal and the hue signal. The color misregistration amount is detected from the color signal appearing in the primary color portion, and based on the color misregistration amount, among the plurality of color images,
Since color misregistration correction is performed by shifting a specific image with respect to a reference image, the circuit scale can be reduced, and good color misregistration correction can be performed.

[Brief description of the drawings]

1 to 5 relate to a first embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration of the color misregistration correction device, FIG. 2 is a block diagram showing the configuration of the endoscope device, FIG. 3 is a side view showing the entire endoscope device, and FIG. FIG. 4 (b) is an explanatory diagram showing a color distribution on a color difference plane of an endoscope image having no color shift, and FIG. 4 (b) is a color distribution of an endoscope image having a color shift on a color difference plane. FIG. 5 (a)
FIG. 5B is an explanatory view showing a matching area of a G image, FIG. 5B is an explanatory view showing a matching area and a scan area of an R or B image, and FIG. 6 is a diagram of a color misregistration correcting apparatus according to a second embodiment of the present invention. FIG. 7 is a block diagram showing the configuration, and FIG. 7 is a block diagram showing the configuration of a color misregistration correction apparatus according to a third embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope 100 ... Color misregistration correction device 111 ... Primary color part detection circuit 112 ... Primary color area calculation circuit 113 ... Primary color area minimum value detection circuit 114 ... Shift map memory 115 ... Interpolation processing circuit 116 …… Image reconstruction circuit

Claims (3)

(57) [Claims] 1. A color signal conversion means for inputting image signals of a plurality of colors obtained by frame-sequential imaging and outputting a saturation signal and a hue signal, and a predetermined signal based on the saturation signal and the hue signal. A primary color part specifying means for specifying a primary color part in a coordinate system; and a color shift detecting means for detecting occurrence of a color shift based on a color signal in the primary color part specified in the coordinate system. Endoscope color shift detector. 2. A color signal conversion means for inputting image signals of a plurality of colors obtained by frame sequential imaging and outputting a saturation signal and a hue signal, and a predetermined signal based on the saturation signal and the hue signal. Primary color portion specifying means for specifying a primary color portion in a coordinate system; color misregistration detecting means for detecting color misregistration based on a color signal in the primary color portion specified in the coordinate system; A control circuit capable of controlling the image signals of the plurality of colors so as to shift a specific image with respect to a reference image among the images of the plurality of colors. apparatus. 3. A color signal conversion means for inputting image signals of a plurality of colors obtained by performing frame sequential imaging and outputting a saturation signal and a hue signal, and a predetermined signal based on the saturation signal and the hue signal. Primary color portion specifying means for specifying a primary color portion in a coordinate system; color shift detecting means for detecting a color shift based on a color signal in the primary color portion specified in the coordinate system; color shift detection by the color shift detecting device A color misregistration amount detection unit configured to detect a color misregistration amount based on a result; and the plurality of colors are shifted from a plurality of color images obtained from the plurality of color image signals by shifting a specific image with respect to a reference image. And a control circuit capable of controlling the image signal of, when the specific image is shifted by the control circuit,
Detecting means for detecting a shift amount at which the color misregistration amount detected by the color misregistration amount detecting means is minimized; and detecting an image from the plurality of color image signals based on the shift amount detected by the sensing means. An image reconstructing means for reconstructing a color shift correcting device for an endoscope.