JP2008093225A - Endoscope system and image processing method in this endoscope system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an endoscope system capable of displaying a site observed under a first light condition in a monitor as if the observation is performed under a second light condition. <P>SOLUTION: A signal (R<SB>out</SB>, G<SB>out</SB>, B<SB>out</SB>) imaged by a camera 11 under the first light 10 for illuminating the inside of the living body (a subject 1) is changed into an image signal (X'<SB>1</SB>, Y'<SB>1</SB>, Z'<SB>1</SB>) of a color space independent of a device based on the characteristic information on the first light 10, the camera 11 and the living body (subject 1) at a camera color changing part 12. The characteristic information on this living body is calculated from spectral reflection factors of several points in the living body. Additionally, the image signal (X'<SB>1</SB>, Y'<SB>1</SB>, Z'<SB>1</SB>) is changed into an image signal (X'<SB>2</SB>, Y'<SB>2</SB>, Z'<SB>2</SB>) of a color space independent of a device under the second light means environment from the characteristic information of the second light means recorded beforehand. Further it is changed into an image signal (R<SB>in</SB>, G<SB>in</SB>, B<SB>in</SB>) of a color space dependent on the monitor 15 based on the characteristic information of the color space of the monitor 15 recorded beforehand. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an endoscope system that captures an image of a living tissue and performs image processing, and an image processing method in the endoscope system.

  2. Description of the Related Art Conventionally, endoscope systems that obtain an endoscopic image in a body cavity by irradiating illumination light are widely known. In this type of endoscope system, an electronic endoscope having an imaging unit that guides illumination light from a light source device into a body cavity using a light guide or the like and images a subject by the return light is used by a video processor. An image signal from the imaging means is signal-processed to display an endoscopic image on an observation monitor and observe an observation site such as an affected area.

Since the diagnosis and operation by the endoscope system are performed based on the observation image displayed on the monitor, the color reproducibility of the observation image is faithfully reproduced on the observation monitor for accurate diagnosis and surgery. It is necessary to do. Therefore, in this type of endoscope system, in order to correct variations in color reproducibility due to differences in sensitivity between light source devices, solid-state imaging devices, differences in spectral sensitivity of color filters, variations in video signal processing circuits, and the like. In addition, a white balance correction (white balance adjustment) function is provided. In normal use, a white subject is imaged after starting the endoscope system, the white balance correction function is operated by the operation switch, and the patient is diagnosed and operated after performing the white balance correction. The color reproducibility of the affected area or the like is performed with an observation monitor. In addition to the white balance correction described above, recent endoscope systems are provided with color mode setting means to cope with differences in color rendering due to the lamp type of the light source device and user preferences. The user can set the color reproducibility according to the type and preference of the light source device. Such conventional endoscope systems are disclosed in, for example, Patent Document 1 (Japanese Patent Laid-Open No. 2000-221417) and Patent Document 2 (Japanese Patent Laid-Open No. 2001-127712).
Japanese Patent Laid-Open No. 2000-22214 JP 2001-127712 A

  By the way, it is known that the color perceived by the human visual system looks different depending on the illumination light even if the light entering the eye is the same. The conventional endoscope systems described in Patent Documents 1 and 2 only have a white balance correction function and a function to set a user-favorable color mode for color reproducibility, and such human vision. The system is not considered. In other words, the conventional endoscope system does not aim at faithful color reproduction similar to that under, for example, a surgical light, where a user actually observes a site such as an affected area. For this reason, there is a problem that colors that can be easily separated when actually observing with the naked eye under a surgical light are displayed as difficult colors on the observation monitor, which may hinder examination and treatment. there were.

  In order to solve such a problem, the invention according to claim 1 is an endoscope system that performs color space conversion processing, the first illuminating means for illuminating the inside of the living body, and the first illuminating means. The first illuminating means and the second illuminating means which have an imaging means for imaging the part illuminated by the image sensor and a display device for outputting an image signal, and store the image signal output from the imaging means in advance Then, based on the characteristic information of the imaging means, the display device, and the characteristic information of the living body that is the subject, the color of the subject under the second illumination means environment is finally output to the display device, and the biological characteristic information is And calculating from the spectral reflectance at a plurality of points in the living body.

  The invention according to claim 2 is an image processing method in an endoscope system that performs color space conversion processing, and is illuminated by a first illumination unit that illuminates the inside of a living body, and the first illumination unit The first illuminating means, the second illuminating means, and the imaging means, which have an imaging means for imaging a part and a display device for outputting an image signal, and that store the image signal output from the imaging means, Based on the characteristic information of the display device and the characteristic information of the living body that is the subject, the color of the subject in the second illumination unit environment is finally output to the display device. It is calculated from the spectral reflectance of a point.

  The invention according to claim 3 is an endoscope system that performs color space conversion processing, and images a first illumination unit that illuminates the inside of a living body and a portion illuminated by the first illumination unit The imaging means and the image signal output from the imaging means are stored in the first illumination means environment based on the first illumination means stored in advance, the characteristic information of the imaging means and the characteristic information of the living body that is the subject. First color space conversion means for converting to an image signal in a color space independent of the device, and biological information and second illumination means for storing in advance the image signal output from the first color space conversion means Based on the characteristic information of the second lighting means, the second color space conversion means for converting the image signal of the color space independent of the device under the environment of the second illumination means, and the characteristic information of the color space of the display device stored in advance Depending on the display device And a third color space conversion means for converting into an image signal of the existing color space, and finally outputs the color under the environment of the second illumination means to the display device. It is calculated from the spectral reflectance at a plurality of points.

  The invention according to claim 4 is the endoscope system according to claim 3, wherein the image signal after being converted by the first color space conversion means and the second color space conversion means is XYZ. It is a signal.

  The invention according to claim 5 is the endoscope system according to claim 3 or claim 4, wherein the first color space conversion means is a matrix conversion means, or a gamma correction means and a matrix. It consists of a combination of conversion means.

  The invention according to claim 6 is the endoscope system according to any one of claims 3 to 5, wherein the second color space conversion means is a matrix conversion means. .

  The invention according to claim 7 is the endoscope system according to any one of claims 3 to 6, wherein the third color space conversion means is matrix conversion means, or matrix conversion means and gamma correction It is a combination of means or a lookup table.

  The invention according to claim 8 is an image processing method in an endoscope system that performs color space conversion processing, and is illuminated by the first illumination unit that illuminates the inside of the living body, and the first illumination unit The first illumination based on the imaging means for imaging the part and the image signal output from the imaging means based on the first illumination means, the characteristic information of the imaging means, and the characteristic information of the living body that is the subject First color space conversion means for converting to an image signal in a color space independent of the device in the environment, and the image signal output from the first color space conversion means, the biological characteristic information stored in advance and the first A second color space converting means for converting the image signal of the color space independent of the device in the environment of the second lighting means based on the characteristic information of the second lighting means, and the color space of the display device stored in advance. Based on characteristic information And a third color space converting means for converting the image signal into a color space depending on the display device, and finally outputting the color under the second illumination means environment to the display device, The characteristic information is calculated from spectral reflectances at a plurality of points in the living body.

  The invention according to claim 9 is an endoscope system that performs color space conversion processing, and images a first illumination unit that illuminates the inside of a living body and a portion illuminated by the first illumination unit The imaging means and the image signal output from the imaging means are stored in the first illumination means environment based on the first illumination means stored in advance, the characteristic information of the imaging means and the characteristic information of the living body that is the subject. First color space conversion means for converting to an image signal in a device-independent color space, and characteristics of the first and second illumination means that store in advance the image signal output from the first color space conversion means Based on the information, based on the second color space conversion means for converting the image signal of the color space independent of the device in the second illumination means environment, and the color space characteristic information of the display device stored in advance, Color sky depending on the display device And a third color space conversion means for converting to the image signal, and finally outputs the color under the second illumination means environment to the display device, the biological characteristic information is a plurality of points in the living body It is calculated from the spectral reflectance.

  The invention according to claim 10 is the endoscope system according to claim 9, wherein the image signal after being converted by the first color space conversion means and the second color space conversion means is XYZ. It is a signal.

  The invention according to claim 11 is the endoscope system according to claim 9 or claim 10, wherein the first color space conversion means is a matrix conversion means, or a gamma correction means and a matrix. It consists of a combination of conversion means.

  The invention according to claim 12 is the endoscope system according to any one of claims 9 to 11, wherein the second color space conversion means is a matrix conversion means. .

  The invention according to claim 13 is the endoscope system according to any one of claims 9 to 12, wherein the third color space conversion means is a matrix conversion means, or a matrix conversion means and a gamma correction. It is a combination of means or a lookup table.

  The invention according to claim 14 is an image processing method in an endoscope system that performs color space conversion processing, and is illuminated by a first illumination unit that illuminates the inside of a living body, and the first illumination unit. The first illumination based on the imaging means for imaging the part and the image signal output from the imaging means based on the first illumination means, the characteristic information of the imaging means, and the characteristic information of the living body that is the subject First color space conversion means for converting to an image signal in a color space independent of the device under the environment, and first and second image signals output from the first color space conversion means are stored in advance. Based on the characteristic information of the illumination means, the second color space conversion means for converting the image signal of the color space independent of the device in the second illumination means environment, and the color space characteristic information of the display device stored in advance Based on the display A third color space conversion means for converting the image signal into a color space depending on the chair, and finally outputting the color under the second illumination means environment to the display device, the biological characteristic information is And calculating from the spectral reflectance at a plurality of points in the living body.

  The invention according to claim 15 is an endoscope system that performs color space conversion processing, and images a first illumination unit that illuminates the inside of a living body and a portion illuminated by the first illumination unit Based on the characteristics information of the imaging means and the first illumination means, the second illumination means, the imaging means, and the biological information as the subject stored in advance, the image signal output from the imaging means is stored in the second A color space that depends on the display device based on the color space characteristic information of the display device that has been stored in advance, and a first color space conversion device that converts the image signal into a color space that does not depend on the device Second color space conversion means for converting to an image signal, and finally outputting the color under the second illumination means environment to the display device, the biological characteristic information is a plurality of points in the biological body It is calculated from the spectral reflectance. The

  The invention according to claim 16 is the endoscope system according to claim 15, wherein the first color space conversion means is composed of matrix conversion means or a combination of gamma correction means and matrix conversion means. It is characterized by.

  The invention according to claim 17 is the endoscope system according to claim 15 or 16, wherein the second color space conversion means is a matrix conversion means, or a combination of matrix conversion means and gamma correction means. Or a look-up table.

  The invention according to claim 18 is an image processing method in an endoscope system that performs color space conversion processing, and is illuminated by a first illumination unit that illuminates the interior of a living body, and the first illumination unit An imaging unit that images a region, and an image signal output from the imaging unit is preliminarily stored based on the first illumination unit, the second illumination unit, characteristic information of the imaging unit, and characteristic information of a living body that is a subject. Based on the first color space conversion means for converting the image signal of the color space independent of the device under the second illumination means environment and the color space characteristic information of the display device stored in advance, the display device Second color space conversion means for converting into an image signal of a dependent color space, and finally outputs a color under the environment of the second illumination means to the display device. Calculated from spectral reflectance at multiple points It is characterized by being put out.

  The invention according to claim 19 is an endoscope system that performs color space conversion processing, and images a first illumination unit that illuminates the inside of a living body and a portion illuminated by the first illumination unit An imaging unit, and image signals output from the imaging unit, the first illumination unit, the second illumination unit, characteristic information of the imaging unit, characteristic information of the living body serving as a subject, and the color of the display device, which are stored in advance Based on the characteristic information of the space, it has first color space conversion means for converting into an image signal of a color space depending on the display device in the second lighting means environment, and finally the second lighting means environment The lower color is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body.

  The invention according to claim 20 is the endoscope system according to claim 19, wherein the first color space conversion means is a matrix conversion means or a combination of a gamma correction means and a matrix conversion means. It is characterized by.

  The invention according to claim 21 is an image processing method in an endoscope system that performs color space conversion processing, and is illuminated by a first illumination unit that illuminates the inside of a living body, and the first illumination unit Imaging means for imaging a part, image signals output from the imaging means, the first illumination means, the second illumination means, the characteristic information of the imaging means, the characteristic information of the living body that is the subject, Based on the characteristic information of the color space of the display device, the first color space conversion means for converting the image signal of the color space depending on the display device under the second illumination means environment, and finally the second The color under the illumination means environment is output to a display device, and the characteristic information of the living body is calculated from the spectral reflectances at a plurality of points in the living body.

  According to the endoscope system of the present invention, the part observed under the first illumination condition can be displayed on the monitor as if it was observed under the second illumination condition. That is, the endoscope system of the present invention performs color reproduction under a second illumination (for example, a surgical light) where a user actually observes a site such as an affected area under the first illumination. Since colors that can be separated with the naked eye are displayed on the monitor as colors that can be separated, inspection and treatment can be performed in a state closer to observation with the naked eye. Further, according to the endoscope system of the present invention, color reproduction is performed under the second illumination as described above, so that color reproduction close to the user's memory color is realized, and an image that is easy for the user's intuition to work is achieved. Since it can provide to a monitor, after observing an affected part site | part with a monitor, a user's discomfort at the time of shifting to a laparotomy can be eliminated and safety can be improved.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram for explaining the principle of an endoscope system according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a subject, 10 denotes first illumination that emits irradiation light for irradiating the subject 1, 11 denotes a camera that captures an observation site in the body cavity, and 12 denotes a camera color conversion unit that performs image processing on the output of the camera 11. , 13 is an illumination color conversion unit that processes the output from the camera color conversion unit 12, 14 is a monitor color conversion unit that converts the output from the illumination color conversion unit 13 into a monitor input, and 15 is an endoscope image display. A monitor for observing an observation site such as an affected part, 20 indicates first illumination, camera and subject characteristic information, 21 indicates second illumination characteristic information, and 22 indicates monitor characteristic information.

The endoscope system of the present invention includes all components other than the subject 1 in FIG. In the endoscope system, a first illumination 10 that illuminates a subject 1 is imaged by a camera 11, and the camera 11 outputs RGB signals. When the camera output of the video imaged under the first illumination 10 is (R _out , G _out , B _out ), the camera color conversion unit 12 takes into account the first illumination, camera, and subject characteristic information 20. Then, this is converted into (X ′ ₁ , Y ′ ₁ , Z ′ ₁ ).

  When image data is transmitted between devices such as a camera 11 that captures an image and a monitor 15 that outputs an image, that is, an image or display output captured by an arbitrary device on the input side (hereinafter referred to as an input device). When the displayed image is displayed and output by another device on the output side (hereinafter referred to as an output device), the input device or the output device has RGB data (such as CMYK data) defined for each device. Each processing is performed based on the image data. For this reason, for example, a large color shift occurs between the image in the input device and the image in the output device due to the difference in the characteristics of the color filter incorporated in the camera as the input device and the phosphor and color filter of the monitor as the output device.

  Therefore, in the present invention, the color space of image data defined for each device is an intermediate color of XYZ (CIE / XYZ), which is a device-independent color space defined by the CIE (International Lighting Commission). Image processing that makes the color of the image in the input device and the color of the image in the output device the same at the colorimetric value level within the range of the capabilities of the device, such as stability and color reproduction area, by converting to space Adopt the method.

  Now, even if the spectral sensitivity of the camera is not linear conversion of the color matching function, if the camera output is linear with respect to the incident light and the spectral reflectance of the subject subject is sufficiently limited, the camera color conversion unit 12 If the color conversion parameter (matrix) in P is P, the camera color conversion unit 12

で十分正確に近似することができる（詳細は後述）。カメラの出力が入射光に対して線形でない場合は、ルックアップテーブル等を用いて線形になるように補正すればよい。次に照明色変換部１３では、第１の照明と第２の照明、又は第２の照明と生体の照明の特性情報２１を加味して、（Ｘ'₁，Ｙ'₁，Ｚ'₁）を（Ｘ'₂，Ｙ'₂，Ｚ'₂）に変換する。すなわち、照明色変換部１３における色変換パラメータ（マトリクス）をQとすると、照明色変換部１３では

Can be approximated sufficiently accurately (details will be described later). When the output of the camera is not linear with respect to the incident light, it may be corrected to be linear using a lookup table or the like. Next, the illumination color conversion unit 13 takes into account the characteristic information 21 of the first illumination and the second illumination, or the second illumination and the biological illumination, and (X ′ ₁ , Y ′ ₁ , Z ′ ₁ ). Is converted to (X ′ ₂ , Y ′ ₂ , Z ′ ₂ ). That is, if the color conversion parameter (matrix) in the illumination color conversion unit 13 is Q, the illumination color conversion unit 13

で十分正確に近似することができる（詳細は後述）。ここで、第２の照明とは、不図示のユーザーが患部等の観察部位を実際に観察する際に用いられる照明等である。なお、この第２の照明については図１においては図示されていない。次に、モニタ色変換部１４では、照明色変換部１３からの出力を受けて、モニタ１５に入力するための信号（Ｒ_in，Ｇ_in，Ｂ_in）に変換する。まず、理想的な加法混色を仮定して決定した色変換パラメータ（マトリクス）をRとして、照明色変換部13から出力された(X'₂ , Y'₂, Z'₂)を(R'_in, G'_in, B'_in)に変換する。

Can be approximated sufficiently accurately (details will be described later). Here, the second illumination is illumination used when a user (not shown) actually observes an observation site such as an affected area. The second illumination is not shown in FIG. Next, the monitor color conversion unit 14 receives the output from the illumination color conversion unit 13 and converts it into signals (R _in , G _in , B _in ) for input to the monitor 15. First, assuming that the color conversion parameter (matrix) determined on the assumption of an ideal additive color mixture is R, (X ′ ₂ , Y ′ ₂ , Z ′ ₂ ) output from the illumination color conversion unit 13 is (R ′ _in , G ' _in , B' _in ).

次に、一般にモニタのガンマ特性は非線形であるため、(R'_in, G'_in, B'_in)を次式で(R_in, G_in, B_in)に変換する。
Ｒ_in ＝ ２５５×（ Ｒ’_in ／ ２５５）^1/2.2
Ｇ_in ＝ ２５５×（ Ｇ’_in ／ ２５５）^1/2.2 （４）
Ｂ_in ＝ ２５５×（ Ｂ’_in ／ ２５５）^1/2.2
ここでは、モニタのガンマ特性がR,G,Bともに2.2であり、RGB信号がいずれも8bitの整数値で表されているものとしている。モニタのガンマ特性が2.2以外である場合も同様であることは言うまでもない。また、(4)式の変わりに、モニタのガンマ特性を線形に補正するようなルックアップテーブルを用いても良い。また、(3)式と(4)式の変わりに(X'₂ , Y'₂, Z'₂)を直接(R_in, G_in, B_in)に変換するような3次元ルックアップテーブルを用いても良い。

Next, since the gamma characteristic of the monitor is generally non-linear, (R ′ _in , G ′ _in , B ′ _in ) is converted into (R _in , G _in , B _in ) by the following equations.
R _in = 255 × (R ′ _in / 255) ^{1 / 2.2}
_{G in = 255 × (G '} in / 255) 1 / 2.2 (4)
B _in = 255 × (B ′ _in / 255) ^{1 / 2.2}
Here, it is assumed that the gamma characteristics of the monitor are 2.2 for R, G, and B, and the RGB signals are all represented by 8-bit integer values. It goes without saying that the same applies when the gamma characteristic of the monitor is other than 2.2. Further, instead of the equation (4), a look-up table that linearly corrects the gamma characteristic of the monitor may be used. In addition, instead of (3) and (4), a 3D lookup table that directly converts (X ' ₂ , Y' ₂ , Z ' ₂ ) to (R _in , G _in , B _in ) It may be used.

In the endoscope system according to the embodiment of the present invention having the above-described configuration, the color conversion parameter (matrix) P in the camera color conversion unit 12, the color conversion parameter (matrix) Q in the illumination color conversion unit 13, and the monitor If the respective color conversion parameters (matrix) R in the color conversion unit 14 can be obtained, appropriate input signals (R _in , G _in , B _in ) to the monitor 15 can be obtained.

  Hereinafter, a method for obtaining the color conversion parameters (matrix) P, Q, and R in the endoscope system according to the embodiment of the present invention will be described. First, how to obtain the color conversion parameter (matrix) P will be described.

  The sensitivity of the eye to the equal energy spectrum determined by the CIE (International Commission on Illumination) is called a spectral stimulus value, and this sensitivity curve is called a color matching function. This color matching function is

とする。なお、等色関数は、人間の目に対応する分光感度であるということもできる。図８は、等色関数の特性曲線を示す図である。また、カメラ１１の各チャンネルの分光感度特性を、r(λ),g(λ),b(λ) とする。なお、カメラ１１の分光感度特性は前記等色関数の線形変換とはなっていない。図９は、カメラ１１のr(λ),g(λ),b(λ)の 分光感度特性曲線を示す図である。また、第１の照明手段の分光特性をs₁(λ)とする。図１０は、第１の照明１０の波長分布特性曲線を示す図である。

And It can be said that the color matching function is spectral sensitivity corresponding to human eyes. FIG. 8 is a diagram illustrating a characteristic curve of a color matching function. Further, the spectral sensitivity characteristics of each channel of the camera 11 are represented by r (λ), g (λ), b (λ). The spectral sensitivity characteristic of the camera 11 is not a linear conversion of the color matching function. FIG. 9 is a diagram showing spectral sensitivity characteristic curves of r (λ), g (λ), and b (λ) of the camera 11. Further, the spectral characteristic of the first illumination means is s ₁ (λ). FIG. 10 is a diagram showing a wavelength distribution characteristic curve of the first illumination 10.

Further, let h _i (λ) be the spectral reflectance of a subject in a typical living body. FIG. 11 is a diagram illustrating a characteristic curve of the spectral reflectance h _i (λ) (i = 1 to 32) of a representative living body (subject). Here, in the endoscope system according to the embodiment of the present invention, a certain number of spectral reflectances h _i (λ) of representative subjects in a living body are sampled and used in the camera color conversion unit 12. A color conversion parameter (matrix) P including characteristic information of the first illumination 10, the camera 11, and the subject 1 is obtained. Specifically, a living body is, for example, a pig that is considered to approximate a color in a human body cavity, and samples of a plurality of organs in the living body are measured. In the present invention, based on any 10 points of the spectral reflectances h _i (λ) at a plurality of points in the living body, the camera outputs (R _out , G _out , B _out ) to (X ′ ₁ , Y ′ _1). , Z ′ ₁ ), a color conversion parameter (matrix) P is obtained. If a matrix is created with some sample points in this way, other points can be estimated correctly.

With respect to the reflectance h _i (λ) (i = 1 to 10) of a representative living body (subject), the camera output and the colorimetric value under the first illumination condition are calculated by the following equations (5), respectively. can do. Here, R _i , G _i , and B _i indicate R _out , G _out , and B _out when the i-th sample living body is imaged by the camera 10, respectively.

また、第１の照明１０条件下での三刺激値は下式（６）にて計算することができる。

The tristimulus value under the first illumination 10 condition can be calculated by the following equation (6).

ここで、第１の照明１０の条件下での代表的な被写体のカメラ出力（Ｒ_out，Ｇ_out，Ｂ_out）を並べたマトリクスCを以下の式で定義する。

Here, a matrix C in which camera outputs (R _out , G _out , B _out ) of typical subjects under the condition of the first illumination 10 are arranged is defined by the following expression.

また、第１の照明１０条件下での前記代表的な被写体の三刺激値を並べた行列V₁を以下の式で定義する。

Further, a matrix V _{1 in} which tristimulus values of the representative subject under the first illumination 10 condition are arranged is defined by the following expression.

第１の照明１０条件下でのカメラ１１の出力から第1の照明１０条件下での三刺激値を推定するには、

To estimate the tristimulus values under the first illumination 10 condition from the output of the camera 11 under the first illumination 10 condition,

を満たすマトリクスｘ₁を求めればよく、このようなマトリクスは最小二乗法により以下の式（１０）で求められることが知られている。（木村英紀著「線形代数 数理科学の基礎」財団法人東京大学出版会発行、２００３年１２月１９日初版１０９頁乃至１１１頁等参照）

It is known that such a matrix x ₁ satisfying the following equation (10) can be obtained by the least square method. (See Kimura Hideki, “Basics of Linear Algebra and Mathematical Sciences” published by the University of Tokyo Press, December 19, 2003, first edition, pages 109 to 111)

このマトリクスｘ₁を利用して、以下の式でカメラ出力から第1の照明１０条件下での被写体の三刺激値を推定できる。

Using this matrix x ₁ , the tristimulus value of the subject under the first illumination 10 condition can be estimated from the camera output by the following equation.

すなわち、カメラ色変換部１２にて用いられる第１の照明１０、カメラ１１、被写体１の特性情報を含む色変換パラメータ（マトリクス）Pは、

That is, the color conversion parameter (matrix) P including the characteristic information of the first illumination 10, the camera 11, and the subject 1 used in the camera color conversion unit 12 is

によって求めることができる。

Can be obtained.

Next, a method for obtaining the color conversion parameter (matrix) Q in the illumination color conversion unit 13 using the second illumination and biological characteristic information will be described. A matrix V _{2 in} which tristimulus values of the representative subject under the second illumination condition are arranged is defined by the following expression. The tristimulus value under the second illumination condition can be calculated by substituting S ₁ (λ) in the equation (6) with the spectral characteristic S ₂ (λ) of the _second illumination. Here, the second illumination means specifically refers to illumination of halogen, a surgical light, or sunlight, xenon or the like having characteristics close to it.

すると、以下のようにＶ１とＶ２との関係は、マトリクスｘ₂によって、

Then, the relationship between V1 and V2 is expressed by the matrix x ₂ as follows:

と表現することができる。したがって、このようなマトリクスは前述の最小二乗法により以下の式（１５）として求めることができる。

It can be expressed as Therefore, such a matrix can be obtained as the following equation (15) by the above least square method.

このマトリクスｘ₂を利用して、以下の式で第２の照明条件下での被写体の三刺激値を推定できる。

Using this matrix x _2, it can be estimated tristimulus values of the object in the second illumination conditions by the following equation.

すなわち、照明色変換部１３にて用いられる第２の照明の特性情報を含む色変換パラメータ（マトリクス）Qは、

That is, the color conversion parameter (matrix) Q including the second illumination characteristic information used in the illumination color conversion unit 13 is:

によって求めることができる。

Can be obtained.

  Next, a method for obtaining the color conversion parameter (matrix) Q in the illumination color conversion unit 13 using the first and second illuminations and the biological characteristic information will be described. The tristimulus values of the fully diffuse reflecting surface under the conditions of the first illumination 10 are

第２の照明条件下での完全拡散反射面の三刺激値を、

The tristimulus value of the fully diffuse reflecting surface under the second illumination condition is

とするとき、以下のように定義される色変換マトリクスｄを利用して、第1の照明条件下での被写体の三刺激値（Ｘ_w1，Ｙ_w1，Ｚ_w1）から第2の照明条件下での三刺激値（Ｘ_w2，Ｙ_w2，Ｚ_w2）を推定することができる。

When using the color conversion matrix d defined as follows, the tristimulus values (X _w1 , Y _w1 , Z _w1 ) of the subject under the first illumination condition are used for the second illumination condition. The tristimulus values (X _w2 , Y _w2 , Z _w2 ) can be estimated.

すなわち、

That is,

となる。

It becomes.

  Next, a method for obtaining the color conversion parameter (matrix) R in the monitor color conversion unit 14 will be described. The monitor color conversion unit 14 is a well-known color of the monitor 15 defined by the display color data input to the monitor 15 and the color actually displayed by the monitor 15 based on the display color data. The monitor characteristic information which is the color reproduction characteristic indicating the relationship is stored in advance. In general, if Xr, Yr, Zr are R tristimulus values, Xg, Yg, Zg are G tristimulus values, and Xb, Yb, Zb are B tristimulus values, (R, G, B) and (X .YZ), ideally

ただし、

However,

の関係が成立することが知られているので、モニタ色変換部１４におけるＲは、

Since it is known that this relationship is established, R in the monitor color conversion unit 14 is

から、

From

と求めることができる。

It can be asked.

With the method according to the present embodiment described above, the first illumination 10 and the camera 11 obtained from any 10 points of the spectral reflectances h _i (λ) of the representative living body (subject) shown in FIG. The color conversion parameter (matrix) P including the characteristic information of the subject 1 is

であった。このマトリクスの計算によって、ｉ＝１〜３２のカメラ出力（Ｒ_out，Ｇ_out，Ｂ_out）から（Ｘ'₁，Ｙ'₁，Ｚ'₁）を求めたものが表１である。すなわち、カメラ出力（Ｒ_out，Ｇ_out，Ｂ_out）に基づいて（Ｘ'₁，Ｙ'₁，Ｚ'₁）を推定したものの結果である。

Met. Table 1 shows (X ′ ₁ , Y ′ ₁ , Z ′ ₁ ) obtained from the camera outputs (R _out , G _out , B _out ) of i = 1 to 32 by calculation of this matrix. That is, it is a result of estimating (X ′ ₁ , Y ′ ₁ , Z ′ ₁ ) based on the camera outputs (R _out , G _out , B _out ).

次に、本実施形態において、推定値と測定値との間の評価に用いたＬ^*ａ^*ｂ^*表色系について説明する。Ｌ^*ａ^*ｂ^*表色系とは、ＣＩＥが１９７６年に定めた均等色空間のひとつである。次の三次元直交座標を用いる色空間を Ｌ^*ａ^*ｂ^*色空間といい、この色空間を用いた表色系を Ｌ^*ａ^*ｂ^*表色系またはＣＩＥＬＡＢ表色系（シー・アイ・イー・エル・エー・ビーまたはシーラブ）といいう。
明度指数を

Next, the L ^* a ^* b ^* color system used for the evaluation between the estimated value and the measured value in this embodiment will be described. The L ^* a ^* b ^* color system is one of the uniform color spaces defined by the CIE in 1976. The color space using the following three-dimensional orthogonal coordinates is called the L ^* a ^* b ^* color space, and the color system using this color space is the L ^* a ^* b ^* color system or CIELAB color system (see・ It is called “ELB or Sea Love”.
Brightness index

と定義する。
また、クロマティクネス指数

It is defined as
Also, the chromaticness index

と定義する。
ただし、

It is defined as
However,

である。

It is.

  Here, X, Y, and Z are tristimulus values in the XYZ color system of the sample. Xn, Yn, and Zn are the tristimulus values of the complete diffuse reflection surface. When X / Xn, Y / Yn, and Z / Zn have 0.008856 or less, calculation is performed by replacing the corresponding cubic root terms in the equation (30) with the following equations, respectively.

なお、本実施形態ではＸｎ＝１１６９．５８８、Ｙｎ＝１１７６．４８、Ｚｎ＝１１１４．７８８とした。

In this embodiment, Xn = 1169.588, Yn = 1176.48, and Zn = 1114.788.

On the other hand, the measured values of the representative locations of the living body with i = 1 to 32 are shown in Table 2. In the table, (X ₁ , Y ₁ , Z ₁ ) indicates an actually measured value that is not estimated using a matrix, and the previous (X ′ ₁ , Y ′ ₁ , Z ′ ₁ ) Corresponds to the comparison target. If the difference between the estimated value L ^* a ^* b ^* and the measured value L ^* a ^* b ^* is ΔL ^* , Δa ^* , and Δb ^* , respectively, the color difference ΔE is

で求められる。

Is required.

表１におけるＬ^*ａ^*ｂ^*色度座標（推定値）と表２におけるＬ^*ａ^*ｂ^*色度座標（実測値）とを、Ｌ^*ａ^*ｂ^*色度図に図示したものが図１２である。図１２に示すように、Ｌ^*ａ^*ｂ^*色度図中、推定値と実測値とはほぼ同一点にプロットされていることがわかる。また、表２において示すように、推定値と測色値との色差ΔＥについても充分小さな値に集束していることがわかる。

L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 1 and L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 2 are illustrated in the L ^* a ^* b ^* chromaticity diagram. FIG. As shown in FIG. 12, in the L ^* a ^* b ^* chromaticity diagram, it can be seen that the estimated value and the actually measured value are plotted at substantially the same point. Further, as shown in Table 2, it can be seen that the color difference ΔE between the estimated value and the colorimetric value is also converged to a sufficiently small value.

Next, from the tristimulus values X ′ ₁ , Y ′ ₁ , and Z ′ ₁ (estimated values) of the subject under the first illumination condition, the second illumination condition is obtained using the second illumination and the biological characteristic information. Table 3 shows the results of estimation of the tristimulus values X ′ ₂ , Y ′ ₂ , and Z ′ ₂ of the subject. Table 4 shows measured values X ₂ , Y ₂ , and Z ₂ of tristimulus values. The definition of the color difference ΔE is the same as described above. Here, Xn = 1321.493, Yn = 1361.721, and Zn = 759.275. The color conversion parameter Q is

を用いた。また、表３におけるＬ^*ａ^*ｂ^*色度座標（推定値）と表４におけるＬ^*ａ^*ｂ^*色度座標（実測値）とを、Ｌ^*ａ^*ｂ^*色度図に図示したものが図１３である。

Was used. Further, L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 3 and L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 4 are illustrated in the L ^* a ^* b ^* chromaticity diagram. The thing is FIG.

次に第１の照明条件下での被写体の三刺激値Ｘ'₁，Ｙ'₁，Ｚ'₁（推定値）から、第１及び第２の照明の特性情報を用いて、第２の照明条件下での被写体の三刺激値Ｘ'₂，Ｙ'₂，Ｚ'₂を推定した結果を表５に示す。また、表６には、三刺激値の実測値Ｘ₂，Ｙ₂，Ｚ₂を示す。色差ΔＥの定義は前述と同様である。ここでは、Ｘｎ＝１３２１．４９３、Ｙｎ＝１３６１．７２１、Ｚｎ＝７５９．２７５とした。また、比例変換マトリクスは次のものを用いた。

Next, the second illumination is performed using the first and second illumination characteristic information from the tristimulus values X ′ ₁ , Y ′ ₁ , and Z ′ ₁ (estimated values) of the subject under the first illumination condition. Table 5 shows the results of estimating the tristimulus values X ′ ₂ , Y ′ ₂ and Z ′ ₂ of the subject under the conditions. Table 6 shows measured values X ₂ , Y ₂ , and Z ₂ of tristimulus values. The definition of the color difference ΔE is the same as described above. Here, Xn = 1321.493, Yn = 1361.721, and Zn = 759.275. The proportional transformation matrix used was as follows.

表５におけるＬ^*ａ^*ｂ^*色度座標（推定値）と表６におけるＬ^*ａ^*ｂ^*色度座標（実測値）とを、Ｌ^*ａ^*ｂ^*色度図に図示したものが図１４である。

L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 5 and L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 6 are shown in the L ^* a ^* b ^* chromaticity diagram. FIG.

このように本発明の内視鏡システムによれば、第１の照明条件下で観察した部位を、あたかも第２の照明条件下で観察したかの如くモニタ１５に表示できる。すなわち、本発明の内視鏡システムは、第１の照明下における患部等の部位を、ユーザーが実際に観察する（例えば無影灯などの）第２の照明下での色再現を行うので、肉眼で分離できる色はモニタ上でも分離できる色として表示されるため、肉眼での観察により近い状態での検査、治療が可能になる。また、本発明の内視鏡システムによれば、上記のように第２の照明下での色再現を行うので、ユーザーの記憶色に近い色再現を実現し、ユーザーの直感が働きやすい画像をモニタに提供できるので、モニタで患部部位を観察した後、開腹手術に移行した場合のユーザーの違和感をなくし安全性を高めることができる。

Thus, according to the endoscope system of the present invention, the part observed under the first illumination condition can be displayed on the monitor 15 as if it was observed under the second illumination condition. That is, the endoscope system of the present invention performs color reproduction under a second illumination (for example, a surgical light) where a user actually observes a site such as an affected area under the first illumination. Since colors that can be separated with the naked eye are displayed on the monitor as colors that can be separated, inspection and treatment can be performed in a state closer to observation with the naked eye. Further, according to the endoscope system of the present invention, color reproduction is performed under the second illumination as described above, so that color reproduction close to the user's memory color is realized, and an image that is easy for the user's intuition to work is achieved. Since it can provide to a monitor, after observing an affected part site | part with a monitor, a user's discomfort at the time of shifting to a laparotomy can be eliminated and safety can be improved.

  Next, another embodiment of the present invention will be described with reference to the drawings. FIG. 2 is a block diagram for explaining the principle of an endoscope system according to another embodiment of the present invention. In FIG. 2, 1 is a subject, 10 is a first illumination that emits irradiation light that irradiates the subject 1, 11 is a camera that images an observation site in a body cavity, 16 is a camera color conversion unit and illumination color conversion unit, and 14 is A monitor color conversion unit that converts the output from the camera color conversion unit and the illumination color conversion unit 16 into a monitor input, 15 is a monitor that displays an endoscopic image and observes an observation site such as an affected area, and 23 is a first monitor. Illumination, second illumination, camera, subject characteristic information, and 22 indicate monitor characteristic information. In the previous embodiment, the camera color conversion unit 12 and the illumination color conversion unit 13 are separate, but in the present embodiment, these are combined as a camera color conversion unit and an illumination color conversion unit 16.

The endoscope system of the present embodiment includes all components other than the subject 1 in FIG. In the endoscope system, a first illumination 10 that illuminates a subject 1 is imaged by a camera 11, and the camera 11 outputs RGB signals. When the camera output of the video imaged under the first illumination 10 is R _out , G _out , B _out , the camera color conversion unit and the illumination color conversion unit 16 use the first illumination, the second illumination, and the camera. Taking into account the characteristic information 23 of the subject, this is converted into X ′ ₂ , Y ′ ₂ , Z ′ ₂ . That is, when the color conversion parameter (matrix) in the camera color conversion unit and the illumination color conversion unit 16 is L, the camera color conversion unit and the illumination color conversion unit 16

が成立する。（Ｘ'₂，Ｙ'₂，Ｚ'₂）をモニタ１５に入力するための信号（Ｒ_in，Ｇ_in，Ｂ_in）に変換するためのモニタ色変換部１４における色変換パラメータ（マトリクス）Rについては、左記の実施形態と同様なので説明を省略する。

Is established. Color conversion parameters (matrix) R in the monitor color conversion unit 14 for converting (X ′ ₂ , Y ′ ₂ , Z ′ ₂ ) into signals (R _in , G _in , B _in ) for input to the monitor 15. Since is the same as the embodiment on the left, the description thereof is omitted.

  Next, a method for obtaining the color conversion parameter (matrix) L in the camera color conversion unit and the illumination color conversion unit 16 will be described. To estimate the tristimulus value under the second illumination condition from the output of the camera 11 without estimating the colorimetric value of the subject 1 under the first illumination 10 condition,

となるマトリクスｘ₃を求めればよい。このようなマトリクスは前述の最小二乗法により以下の式（３８）として求めることができる。

It may be obtained matrix x ₃ to be. Such a matrix can be obtained as the following equation (38) by the above-mentioned least square method.

このマトリクスｘ₃を利用して、以下の式でカメラ出力から第２の照明１０条件下での被写体の三刺激値を推定できる。

Using this matrix x ₃ , the tristimulus value of the subject under the second illumination 10 condition can be estimated from the camera output by the following equation.

すなわち、カメラ色変換部及び照明色変換部１６にて用いられる第１の照明、第２の照明、カメラ、被写体の特性情報２３を含む色変換パラメータ（マトリクス）Ｌは、

That is, the color conversion parameter (matrix) L including the first illumination, the second illumination, the camera, and the subject characteristic information 23 used in the camera color conversion unit and the illumination color conversion unit 16 is:

によって求めることができる。

Can be obtained.

Next, Table 7 shows the result of directly estimating the tristimulus values (X ′ ₂ , Y ′ ₂ , Z ′ ₂ ) of the subject under the second illumination condition from the camera outputs (R _out , G _out , B _out ). Show. Table 8 shows measured values X ₂ , Y ₂ , and Z ₂ of tristimulus values. The definition of the color difference ΔE is the same as described above. Here, Xn = 1321.493, Yn = 1361.721, and Zn = 759.275. In addition, the following color estimation matrix was used.

表７におけるＬ^*ａ^*ｂ^*色度座標（推定値）と表８におけるＬ^*ａ^*ｂ^*色度座標（実測値）とを、Ｌ^*ａ^*ｂ^*色度図に図示したものが図１５である。

L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 7 and L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 8 are shown in the L ^* a ^* b ^* chromaticity diagram. FIG.

次に、これまでに述べた本発明のより詳細な実施の形態を、図面を参照しつつ説明する。図3は図1に示される実施の形態を、実際の内視鏡システムにおける処理に即したブロック図にしたものである。カメラ色変換部12において示されているマトリクスは前記の色変換パラメータ（マトリクス）Pに、照明色変換部13で示されているマトリクスは前記の色変換パラメータ（マトリクス）Qに、またモニタ色変換部14で示されているマトリクスは前記の色変換パラメータ（マトリクス）Rにそれぞれ対応している。

Next, a more detailed embodiment of the present invention described so far will be described with reference to the drawings. FIG. 3 is a block diagram of the embodiment shown in FIG. 1 adapted to processing in an actual endoscope system. The matrix shown in the camera color conversion unit 12 is the color conversion parameter (matrix) P, the matrix shown in the illumination color conversion unit 13 is the color conversion parameter (matrix) Q, and the monitor color conversion. The matrices shown in the section 14 correspond to the color conversion parameters (matrix) R, respectively.

  FIG. 4 is a block diagram of an endoscope system according to another embodiment of the present invention. The embodiment shown in FIG. 4 is a modification of the embodiment shown in FIG. The matrix shown in the camera color conversion unit 12 is the color conversion parameter (matrix) P, the matrix shown in the illumination color conversion unit 13 is the color conversion parameter (matrix) Q, and the monitor color conversion. The matrix shown in the section 14 corresponds to the color conversion parameter (matrix) R as in the previous embodiment, but the difference in this embodiment is that the camera color conversion section 14 Considering the case where the camera output is non-linear with respect to the incident light, the gamma correction processing is performed to linearly correct the camera output before the matrix.

  FIG. 5 is a block diagram of an endoscope system according to another embodiment of the present invention. The embodiment shown in FIG. 5 is a modification of the embodiment shown in FIG. The matrix shown in the camera color conversion unit 12 corresponds to the color conversion parameter (matrix) P, and the matrix shown in the illumination color conversion unit 13 corresponds to the color conversion parameter (matrix) Q. This is the same as the previous embodiment, but the difference in this embodiment is that the monitor color conversion unit 14 replaces the color conversion parameter (matrix) R and the subsequent gamma correction with a three-dimensional lookup table 3D-LUT. It is a point using. In this embodiment, since a lookup table is used instead of a matrix, an error at the time of monitor output can be suppressed as compared with matrix calculation.

Next, a more detailed embodiment of the present invention will be described with reference to the drawings. FIG. 6 is a block diagram in which the embodiment shown in FIG. 2 is adapted to processing in an actual endoscope system. The matrix shown in the camera color conversion unit and the illumination color conversion unit 16 is the color conversion parameter (matrix) L, and the matrix shown in the monitor color conversion unit 14 is the color conversion parameter (matrix) R. It corresponds to each.
FIG. 7 is a block diagram of an endoscope system according to another embodiment of the present invention. In the present embodiment, a camera color conversion unit, an illumination color conversion unit, and a monitor in which all the matrices in the camera color conversion unit 12, the illumination color conversion unit 13, and the monitor color conversion unit 14 of the embodiment shown in FIG. It is characterized by using a color conversion unit 17. As the color conversion parameters (matrix) used in the camera color conversion unit, the illumination color conversion unit, and the monitor color conversion unit 17, for example, a matrix RQP calculated by multiplying the P, Q, and R matrices in the order of processing is used. Use it. In the present embodiment, the scale of the matrix calculation circuit can be reduced by combining all the matrices into one. Needless to say, this effect is the same not only when all the matrices are combined into one, but also when some of the plurality of matrices are combined into one.

  As described above, in any modification of the present invention, the part observed under the first illumination condition can be displayed on the monitor 15 as if it was observed under the second illumination condition. That is, the endoscope system of the present invention performs color reproduction under a second illumination (for example, a surgical light) where a user actually observes a site such as an affected area under the first illumination. Since colors that can be separated with the naked eye are displayed on the monitor as colors that can be separated, inspection and treatment can be performed in a state closer to observation with the naked eye. Further, according to the endoscope system of the present invention, color reproduction is performed under the second illumination as described above, so that color reproduction close to the user's memory color is realized, and an image that is easy for the user's intuition to work is achieved. Since it can provide to a monitor, after observing an affected part site | part with a monitor, a user's discomfort at the time of shifting to a laparotomy can be eliminated and safety can be improved.

It is a block diagram explaining the principle of the endoscope system which concerns on embodiment of this invention. It is a block diagram explaining the principle of the endoscope system which concerns on other embodiment of this invention. It is a block diagram of the endoscope system concerning other embodiments of the present invention. It is a block diagram of the endoscope system concerning other embodiments of the present invention. It is a block diagram of the endoscope system concerning other embodiments of the present invention. It is a block diagram of the endoscope system concerning other embodiments of the present invention. It is a block diagram of the endoscope system concerning other embodiments of the present invention. It is a figure which shows the characteristic curve of a color matching function. It is a figure which shows the r ((lambda)), g ((lambda)), b ((lambda)) spectral sensitivity characteristic curve of the camera of the endoscope system which concerns on embodiment of this invention. 3 is a diagram illustrating a wavelength distribution characteristic curve of the first illumination 10. FIG. It is a diagram showing a characteristic curve of the spectral reflectance _{h i (λ) (i =} 1~32) representative biological (subject). The L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 1 and the L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 2 are shown in the L ^* a ^* b ^* chromaticity diagram. is there. The L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 3 and the L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 4 are shown in the L ^* a ^* b ^* chromaticity diagram. is there. The L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 5 and the L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 6 are shown in the L ^* a ^* b ^* chromaticity diagram. is there. The L ^* a ^* b ^* chromaticity coordinates (estimated values) in Table 7 and the L ^* a ^* b ^* chromaticity coordinates (actually measured values) in Table 8 are shown in the L ^* a ^* b ^* chromaticity diagram. is there.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Subject, 10 ... 1st illumination, 11 ... Camera, 12 ... Camera color conversion part, 13 ... Illumination color conversion part, 14 ... Monitor color conversion part, 15. .. Monitor, 16... Camera color conversion unit and illumination color conversion unit, 20... First illumination, camera, subject characteristic information, 21. Second illumination characteristic information, 22. Monitor characteristic information, 23... First illumination, second illumination, camera, subject characteristic information

Claims (21)

An endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging a part illuminated by the first illuminating means, and a display device for outputting an image signal,
The image signal output from the imaging unit is finally determined based on the first illumination unit, the second illumination unit, the imaging unit, the characteristic information of the display device, and the characteristic information of the living body that is the subject. An endoscope system characterized in that the color of a subject under the second illumination means environment is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body. An image processing method in an endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging a part illuminated by the first illuminating means, and a display device for outputting an image signal,
The image signal output from the imaging unit is finally determined based on the first illumination unit, the second illumination unit, the imaging unit, the characteristic information of the display device, and the characteristic information of the living body that is the subject. In addition, the color of the subject under the second illumination means environment is output to a display device, and the characteristic information of the living body is calculated from the spectral reflectances at a plurality of points in the living body. Method. An endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the imaging unit is not dependent on the device in the first illumination unit environment based on the first illumination unit, the characteristic information of the imaging unit and the characteristic information of the living body that is the subject stored in advance. First color space conversion means for converting to an image signal of a color space;
The image signal output from the first color space conversion means is a device-independent color in the environment of the second illumination means based on the biological characteristic information stored in advance and the characteristic information of the second illumination means. A second color space conversion means for converting to a spatial image signal;
A third color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An endoscope system characterized in that a lower color is output to a display device, and the biological characteristic information is calculated from spectral reflectances at a plurality of points in the biological body. 4. The endoscope system according to claim 3, wherein the image signal after being converted by the first color space conversion unit and the second color space conversion unit is an XYZ signal. 5. The endoscope system according to claim 3, wherein the first color space conversion unit includes a matrix conversion unit or a combination of a gamma correction unit and a matrix conversion unit. 6. The endoscope system according to claim 3, wherein the second color space conversion unit is a matrix conversion unit. 7. The endoscope according to claim 3, wherein the third color space conversion unit is a matrix conversion unit, a combination of matrix conversion unit and gamma correction unit, or a lookup table. system. An image processing method in an endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the imaging unit is not dependent on the device in the first illumination unit environment based on the first illumination unit, the characteristic information of the imaging unit and the characteristic information of the living body that is the subject stored in advance. First color space conversion means for converting to an image signal of a color space;
The image signal output from the first color space conversion means is a device-independent color in the environment of the second illumination means based on the biological characteristic information stored in advance and the characteristic information of the second illumination means. A second color space conversion means for converting to a spatial image signal;
A third color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An image processing method in an endoscope system, characterized in that a lower color is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body. An endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the imaging unit is not dependent on the device in the first illumination unit environment based on the first illumination unit, the characteristic information of the imaging unit and the characteristic information of the living body that is the subject stored in advance. First color space conversion means for converting to an image signal of a color space;
The image signal output from the first color space conversion means is based on the characteristics information of the first and second illumination means stored in advance, and the device-independent color space in the environment of the second illumination means Second color space conversion means for converting to an image signal;
A third color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An endoscope system characterized in that a lower color is output to a display device, and the biological characteristic information is calculated from spectral reflectances at a plurality of points in the biological body. 10. The endoscope system according to claim 9, wherein the image signal after being converted by the first color space conversion unit and the second color space conversion unit is an XYZ signal. 11. The endoscope system according to claim 9, wherein the first color space conversion unit includes a matrix conversion unit or a combination of a gamma correction unit and a matrix conversion unit. 12. The endoscope system according to claim 9, wherein the second color space conversion unit is a matrix conversion unit. 13. The endoscope according to claim 9, wherein the third color space conversion unit is a matrix conversion unit, a combination of matrix conversion unit and gamma correction unit, or a lookup table. system. An image processing method in an endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the imaging unit is not dependent on the device in the first illumination unit environment based on the first illumination unit, the characteristic information of the imaging unit and the characteristic information of the living body that is the subject stored in advance. First color space conversion means for converting to an image signal of a color space;
The image signal output from the first color space conversion means is based on the characteristics information of the first and second illumination means stored in advance, and the device-independent color space in the environment of the second illumination means Second color space conversion means for converting to an image signal;
A third color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An image processing method in an endoscope system, characterized in that a lower color is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body. An endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
Based on the first illumination means, the second illumination means, the characteristic information of the imaging means, and the characteristic information of the living body that is the subject, the image signal output from the imaging means is stored in advance. First color space conversion means for converting into an image signal in a color space independent of the device below,
A second color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An endoscope system characterized in that a lower color is output to a display device, and the biological characteristic information is calculated from spectral reflectances at a plurality of points in the biological body. 16. The endoscope system according to claim 15, wherein the first color space conversion unit includes a matrix conversion unit or a combination of a gamma correction unit and a matrix conversion unit. 17. The endoscope system according to claim 15, wherein the second color space conversion means is a matrix conversion means, a combination of matrix conversion means and gamma correction means, or a lookup table. An image processing method in an endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
Based on the first illumination means, the second illumination means, the characteristic information of the imaging means, and the characteristic information of the living body that is the subject, the image signal output from the imaging means is stored in advance. First color space conversion means for converting into an image signal in a color space independent of the device below,
A second color space conversion means for converting into an image signal of a color space depending on the display device based on characteristic information of the color space of the display device stored in advance, and finally a second illumination means environment An image processing method in an endoscope system, characterized in that a lower color is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body. An endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the image pickup means is stored in advance as the first illumination means, the second illumination means, the characteristic information of the image pickup means, the characteristic information of the living body serving as the subject, and the characteristic information of the color space of the display device The first color space conversion means for converting into an image signal of a color space depending on the display device under the second illumination means environment, and finally the color under the second illumination means environment Is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body. 20. The endoscope system according to claim 19, wherein the first color space conversion unit includes a matrix conversion unit or a combination of a gamma correction unit and a matrix conversion unit. An image processing method in an endoscope system that performs color space conversion processing,
A first illuminating means for illuminating the inside of the living body, an imaging means for imaging the part illuminated by the first illuminating means,
The image signal output from the image pickup means is stored in advance as the first illumination means, the second illumination means, the characteristic information of the image pickup means, the characteristic information of the living body serving as the subject, and the characteristic information of the color space of the display device The first color space conversion means for converting into an image signal of a color space depending on the display device under the second illumination means environment, and finally the color under the second illumination means environment Is output to a display device, and the characteristic information of the living body is calculated from spectral reflectances at a plurality of points in the living body.

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