JP2005124755A - Image processor for endoscope - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor for an endoscope which can appropriately set the diaphragm means of illumination light and improve the precision of an image processing at the time of performing the image processing. <P>SOLUTION: Signals image-picked up by the CCD 30 of an electronic endoscope 2 are processed in a video signal processing block 4 inside a video processor 6 and then IHb calculation or the like is executed in an image processing block 5 when the image processing is ON. A CPU 56 judges whether or not the image processing is ON, and when it is ON, a diaphragm 25 is maintained fully open, appropriate brightness is attained by an electronic shutter, and the image processing is executed. Thus, the fluctuation of an illumination light quantity is suppressed and an accurate image processing result is obtained. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an endoscope image processing apparatus that performs image processing on an image signal of an endoscope.

  In recent years, an image processing apparatus has been used that makes it easy to distinguish between a normal site and a lesioned part in a subject by performing image processing on an endoscopic image obtained from an endoscope. Became.

For example, the conventional example of Japanese Patent Laid-Open No. 6-319695 discloses a device that can calculate the blood information amount from an image signal of an endoscopic image and display it in a pseudo color.
Japanese Patent Laid-Open No. 6-319695

  However, in the above conventional example, although the color tone and brightness of the observation image are good, the calculation accuracy of the blood information amount may be insufficient.

  For this reason, there is a demand for an image processing apparatus that can further improve the results of image processing, such as the accuracy of blood information calculation.

(Object of invention)
The present invention has been made in view of the above-described points. An endoscope image processing apparatus capable of appropriately setting illumination light aperture means and improving the accuracy of image processing when performing image processing. The purpose is to provide.

The present invention relates to an endoscope image processing apparatus for processing an image signal obtained by imaging an inside of a body cavity of a subject with an endoscope.
Image processing based on the signal level of the image signal obtained by the endoscope to perform predetermined processing on the image signal and obtain at least one of a processed image or a processing result value capable of displaying the processing result Means,
Illumination light supply means for supplying illumination light including a visible light region for obtaining the image signal;
A diaphragm means for adjusting the amount of illumination light,
Comprising
When the image processing means is in an operating state, the amount of illumination light through the aperture means is controlled so that an image signal after image processing by the image processing means is appropriate.

  With the above configuration, the amount of illumination light by the diaphragm means is controlled so that the image signal is appropriate, so that the accuracy of image processing can be improved.

  According to the present invention, since the amount of illumination light through the aperture means is controlled so that the image signal is appropriate, the amount of illumination light is set so that the image signal is appropriate, and the accuracy of image processing can be improved. .

  Embodiments of the present invention will be described below with reference to the drawings.

  1 to 14 relate to a first embodiment of the present invention, FIG. 1 shows an overall configuration of an endoscope apparatus including the first embodiment, FIG. 2 shows an internal configuration in FIG. 1, and FIG. 3 shows a rotary filter. 4 shows the transmission characteristics of the RGB filter and the like provided in the rotation filter, FIG. 4 shows a display example of the menu screen, and FIG. 5 changes the endoscope image display area displayed on the monitor screen, and the display position and size. 6 shows a possible region of interest, FIG. 6 shows a display example in which the processed image is displayed in a pseudo color in the region of interest set in the endoscope image display region, FIG. 7 shows a display example different from FIG. FIG. 8 shows the operation of detecting the CCD type and generating the corresponding mask signal, FIG. 9 shows the processing operation of generating the type 1 mask signal in FIG. 8, and FIG. 10 is of interest when image processing is performed. Image processing within the region of interest according to the size of the region FIG. 11 shows the pseudo color processing and the original image display processing operation, FIG. 12 shows the pseudo color processing display processing operation in FIG. 11, and FIG. FIG. 14 shows the processing operation of the imaging control (brightness control of the image signal) using the electronic shutter.

  As shown in FIG. 1, an endoscope apparatus 1 including the present embodiment includes an electronic endoscope 2 including an imaging unit, a light source unit 3 that supplies illumination light to the electronic endoscope 2, and imaging. A video processor 6 including a video signal processing block 4 that performs video signal processing (image signal processing) on the means and an image processing block 5 that performs image processing on an output signal from the video signal processing block 4; A monitor 7 for displaying an image signal output from the processor 6, a monitor image photographing device 8A for photographing a monitor image (endoscopic image) displayed on the monitor 7, and the video processor 6 are connected to the image information. And an image filing device 8B that performs recording and the like, and a keyboard 9 that transmits an image processing ON / OFF instruction signal and inputs patient data.

  The electronic endoscope 2 has an elongated and movable insertion portion 11, for example, and a thick operation portion 12 is connected to the rear end of the insertion portion 11. A flexible universal cord 13 is extended from the side, and a connector 14 at the end of the universal cord 13 is detachably connected to a connector receiving portion 15 of the video processor 6.

  The insertion portion 11 of the electronic endoscope 2 is provided with a rigid distal end portion 16 from the distal end side, a bendable bending portion 17 adjacent to the distal end portion 16, and a long flexible portion 18 having flexibility. It has been. Further, the user can bend the bending portion 17 in the left-right direction or the up-down direction by rotating the bending operation knob 19 provided in the operation portion 12 of the electronic endoscope 2. Further, the operation section 12 of the electronic endoscope 2 is provided with an insertion port 20 that communicates with a treatment instrument channel provided in the insertion section 11.

  Further, a scope switch 10 such as a freeze switch for giving a freeze instruction, a release switch for giving a release instruction, an observation mode changeover switch or the like is provided on the top of the operation unit 12 of the electronic endoscope 2. When the user operates the scope switch 10 to give a freeze instruction, for example, the instruction signal is input to the CPU 56 (see FIG. 2) via the control circuit 40 (see FIG. 2) inside the video processor 6. The CPU 56 controls the memory unit 39 (the R, G, and B memories 39r, 39g, and 39b) so that the freeze image is displayed via the control circuit 40.

  Further, when the user performs a freeze instruction operation from the keyboard 9 or the front panel 55 (see FIG. 2) of the video processor 6, the instruction signal is sent to the control circuit 40 via the CPU 56 (see FIG. 2). The CPU 56 performs corresponding control via the control circuit 40.

  When the user performs a release instruction operation, the CPU 56 first controls the display of the freeze image via the control circuit 40 unless the freeze image is displayed, and sends a release control signal to the monitor image photographing device 8A. The monitor image photographing device 8A takes a picture according to the control signal.

  The user can also operate the keyboard 9 or the front panel 55 of the video processor 6 to input an instruction to turn on image processing and to turn off image processing. When this instruction signal is input, The CPU 56 controls the IHb calculation circuit 61, the IHb average value calculation circuit 62, the luminance detection circuit 67, the invalid area detection circuit 68, and the like of the IHb processing block 44 to perform corresponding image processing.

  When the user operates the observation mode changeover switch to give an observation mode switching instruction, the instruction signal is input to the control circuit 40 inside the video processor 6, and the control circuit 40 is operated by a moving motor 31 described later. Then, the rotation filter 27 is moved to perform control such as switching the observation mode from normal observation to fluorescence observation.

  As shown in FIG. 2, an illumination lens 21 and an objective optical system 22 are attached to the illumination window and the observation window at the distal end portion 16, respectively. For example, a charge coupled device (abbreviated as CCD) 30 is disposed at the imaging position of the objective optical system 22 as a solid-state imaging device.

  A light guide 23 made of a fiber bundle is disposed on the rear end side of the illumination lens 21. The light guide 23 is inserted through the insertion portion 11, the operation portion 12, and the universal cord 13 and is connected to the connector 14. .

  Then, the user connects the connector 14 to the video processor 6 so that the illumination light emitted from the light source unit 3 in the video processor 6 enters the incident end of the light guide 23. Yes.

  The light source unit 3 includes a lamp 24 that generates illumination light. The illumination light of the lamp 24 is incident on a rotary filter 27 rotated by a motor 26 through a diaphragm 25 disposed in the optical path, and the light transmitted through the rotary filter 27 is condensed by a condenser lens. Then, the light is incident on the incident end of the light guide 23.

  The lamp 24 emits illumination light including visible light. The diaphragm 25 is driven by a diaphragm motor 25 a controlled by the control circuit 40.

  In the rotary filter 27, a normal observation RGB filter 28 is disposed on the inner peripheral side, and a fluorescence observation filter 29 is disposed on the outer peripheral side. The rotary filter 27 is moved together with the motor 26 that rotates the rotary filter 27 by a moving motor 31 in a direction perpendicular to the optical path (see reference symbol P in FIG. 1).

  For example, a rack is attached to the motor 26, and the rotary filter 27 and the motor 26 are moved in a direction orthogonal to the optical path (see reference A in FIG. 1) by a moving motor 31 provided with a pinion gear. That is, when the observation mode switching instruction is given, the moving motor 31 moves the rotary filter 27 and the like, and switches the filter arranged in the optical path.

  As shown in FIG. 3A, in this rotary filter 27, the RGB filter 28 for normal observation is arranged on the concentric inner peripheral side, and the fluorescence observation filter 29 is arranged on the concentric outer peripheral side. Then, according to switching between the normal mode and the fluorescence mode, the inner-side RGB filter 28 and the outer-side fluorescence observation filter 29 are selected.

  The RGB filter 28 for normal observation on the inner peripheral side has a transmission characteristic as shown in FIG. That is, the R filter 28a is set to transmit the red wavelength band of 600 to 700 nm, the G filter 28b is set to transmit the green wavelength band of 500 to 600 nm, and the B filter 28c is set to transmit the blue wavelength band of 400 to 500 nm. Yes.

  The fluorescence observation filter 29 provided on the outer peripheral side includes R2, G2, and E filters 29a, 29b, and 29c, and the transmission characteristics thereof are set to the characteristics shown in FIG. That is, the R2 filter 29a is set to transmit 600 to 660 nm, the G2 filter 29b is set to transmit 540 to 560 nm, and the E filter 29c is set to transmit 400 to 470 nm. Note that the transmission characteristics of the R2 filter 29a and the G2 filter 29b are set to low levels, and red and green color signals captured under these narrow-band illumination lights (for simplicity, respectively) R2 and G2 signals are abbreviated) and the fluorescence signal so as to enable pseudo color display for fluorescence observation.

  As shown in FIG. 2, an excitation light cut filter 32 for cutting the excitation light is disposed in front of the CCD 30, and the excitation light cut filter 32 is set to have transmission characteristics as shown in FIG. Has been. Specifically, the excitation light cut filter 32 cuts the wavelength band of 400 to 470 nm, which is the transmission band of the E filter 29c that transmits the excitation light, and shortens the light of the wavelength band of 490 to 700 nm, that is, the short wavelength of the blue band. Transmits visible light excluding a part on the wavelength side.

  The light emitted from the lamp 24 is separated into each wavelength region in time series by the rotary filter 27 and is incident on the incident end of the light guide 23.

  This illumination light is guided to the distal end portion 16 by the light guide 23 and passes through the illumination lens 21 attached to the illumination window on the distal end surface to irradiate the subject such as the site to be inspected in a surface sequential manner. In this case, in the normal observation mode, R, G, B normal observation surface-sequential illumination light is used. In the fluorescence observation mode, the illumination light is R2, G2, and E in the order of frames.

  An object image illuminated by plane-sequential illumination light is imaged on the photoelectric conversion surface by the objective optical system 22 on the CCD 30 disposed at the imaging position of the objective optical system 22, and is converted into an electrical signal by the CCD 30. Converted. When a CCD drive signal is applied by the CCD driver 33, the CCD 30 reads and outputs the signal charge photoelectrically converted and accumulated by the CCD 30. The control circuit 40 (or the CPU 56) controls the CCD driver 33 so that the electronic shutter can be operated to variably control the charge accumulation time of the CCD 30.

  A time-series image signal (imaging signal) that is photoelectrically converted and output from the CCD 30 is input into the video signal processing block 4 and is amplified to a predetermined range of an electrical signal (for example, 0 to 1 volt). Input to the amplifier 34.

  In this case, the time-series image signals are R, G, and B color signals in the normal observation mode, and signals captured under R2 and G2 illumination in the fluorescence observation mode (denoted as R2 and G2), It becomes a fluorescence signal imaged under the excitation light of E.

  The output signal of the amplifier 34 is converted into a digital signal by an A / D converter 35 and further input to an auto gain control circuit (abbreviated as AGC circuit) 36, and the gain is adjusted by the AGC circuit 36 so as to obtain an appropriate level. It is automatically controlled. The signal passed through the AGC circuit 36 is input to a 1-input 3-output selector 37.

  The imaging signals sent in time series are switched to R, G, B color signals or R2, G2, and fluorescence signals by the selector 37 and input to the white balance adjustment circuit 38. The white balance adjustment circuit 38 adjusts the gain for each color signal, that is, adjusts the white balance so that the levels of the R, G, and B color signals are equal when a white subject as a reference is imaged. The output signal of the white balance adjustment circuit 38 is input to the memory unit 39.

  Signals input to time-series examples such as R, G, and B color signals are stored in R, G, and B memories 39r, 39g, and 39b constituting the memory unit 39.

  That is, in the normal observation mode, the R, G, and B color signals are stored in the R, G, and B memories 39r, 39g, and 39b constituting the memory unit 39, respectively. In the fluorescence observation mode, R2, G2, and fluorescence signals are stored in the R, G, and B memories 39r, 39g, and 39b, respectively.

  A / D conversion by the A / D converter 35, switching of the selector 37, control at the time of white balance adjustment, and storage (writing) of color signals to the R, G, B memories 39r, 39g, 39b of the memory unit 39 ) And reading are controlled by the control circuit 40.

  The control circuit 40 sends a reference signal to a synchronization signal generation circuit (abbreviated as SSG in FIG. 2) 41, and the synchronization signal generation circuit 41 generates a synchronization signal synchronized with the reference signal.

  It should be noted that a still image can be displayed by prohibiting writing to the R, G, B memories 39r, 39g, and 39b (also possible with an internal memory in the synchronization circuit 53 described later). Becomes).

  The output signal of the A / D converter 35 is input to a photometric circuit 42 that performs photometry, and the photometric signal is input to the control circuit 40. Then, the control circuit 40 compares the average value obtained by integrating the photometric signal with a reference value (in the case of appropriate brightness), and controls the aperture motor 25a as a dimming signal so as to reduce the difference. The aperture amount (on the illumination optical path) of the diaphragm 25 driven by the diaphragm motor 25a is varied and adjusted to an appropriate illumination light amount.

  The diaphragm motor 25a is provided with a rotary encoder (not shown) as position detecting means for detecting the diaphragm position (corresponding to the opening amount) of the diaphragm 25, and the detection signal of this rotary encoder is sent to the control circuit 40. Entered. Based on this detection signal, the control circuit 40 can detect the position of the diaphragm 25. The control circuit 40 is connected to the CPU 56 through a signal line that sends signals in both directions, and the CPU 56 can also check the position of the diaphragm 25.

  In the case of the normal observation mode, the R, G, B signals read from the R, G, B memories 39r, 39g, 39b are used as the amount of dye serving as the amount of blood information constituting the image processing block 5. The value is input to an IHb processing block 44 that performs processing such as calculation of a value correlated with the amount of hemoglobin (hereinafter abbreviated as IHb).

  In the present embodiment, this IHb processing block 44 calculates pseudo color based on the calculation of the amount (value) of IHb at each pixel and the average value thereof and the value of IHb at each pixel within the set region of interest. The configuration includes an IHb processing circuit unit 45 that performs a pseudo image generation process to be displayed as an image, and an invalid region detection unit 46 that detects an invalid region that is not suitable for image processing for the set region of interest.

  In addition, in this embodiment, when an IHb pseudo color image is displayed as a freeze image, a color misregistration detection circuit 47 that performs color misregistration detection is also provided so that it can be displayed with little color misregistration. The frame sequential signal output from the IHb processing block 44 is subjected to γ correction by the γ correction circuit 50 and further subjected to structure enhancement in the subsequent image processing circuit 51. After that, the patient superimposing circuit 52 superimposes the patient data and the calculated average value of IHb, and then the synchronizing circuit 53 converts the frame sequential signal into a synchronized signal.

  The synchronization circuit 53 has three frame memories inside, and sequentially writes frame-sequential signal data to the temporary three frame memories, and simultaneously reads out the synchronized signals such as synchronized RGB signals. Output.

  The synchronized signals are respectively input to the three D / A converters of the D / A converter 54, converted into analog RGB signals, etc., and then sent to the monitor 7, the monitor image photographing device 8A, and the image filing device 8B. Entered. Note that writing and reading of the frame memory in the synchronization circuit 53 and D / A conversion of the D / A conversion unit 54 are controlled by the control circuit 40. The CPU 56 controls the operations of the γ correction circuit 50, the subsequent image processing circuit 51, and the character superimposing circuit 52.

  The monitor image photographing device 8A is a monitor (not shown) that displays an image or the like as with the monitor 7, and a photograph photographing device (specifically a camera) that records an image or the like displayed on the monitor by photographing. Consists of

  Then, the user causes the monitor 7 to display a normal image (also referred to as an original image) that is illuminated and picked up with normal visible light, or performs an instruction operation on the switch or the keyboard 9 provided on the front panel 55 of the video processor 6. Thus, when an instruction to display an IHb image is issued, the instruction signal is input to the CPU 56, and the CPU 56 controls the IHb processing block 44 and the like in response to the instruction signal.

  When the fluorescence observation mode is set, the R2, G2, and fluorescence signals read from the R, G, and B memories 39r, 39g, and 39b pass through the image synthesis circuit 65, the frame sequential circuit 66, and the like. For example, pseudo color display is performed by using red and green color signals by R2 and G2 and fluorescent signals colored by blue color signals.

  Further, in the present embodiment, even when the electronic endoscope 2 having different identification information (denoted by reference numeral 43 in FIG. 2) that is unique to the endoscope is mounted, the electronic endoscope 2 is accurately identified for these different types. Signal processing can be performed.

  Here, the information unique to the endoscope includes, for example, optical type information such as angle of view and optical zoom, application information (use information for the upper digestive tract or the lower digestive tract, etc.), and the pixels of the CCD 30 installed therein. Information such as numbers.

  In this embodiment, the identification information 43 is detected by the connector 14, the connector receiving portion 15, the detection circuit 57, and the like.

  Note that, as an optimal example of the storage means for the endoscope unique identification information 43, examples using storage means such as RAM and ROM, or examples of distinguishing unique information based on differences in resistance values of resistance elements and the like. Etc. are considered.

  In addition, the present embodiment also has a function of directly detecting type information such as the number of pixels of the image sensor (CCD 30) provided in the electronic endoscope 2 from the signal path related to the CCD 30 among the identification information. For example, the detection circuit 57 detects, for example, a difference in the number of pins of the connector 14 through the connector receiving unit 15 on the signal path that guides the signal from the CCD 30 to the subsequent amplification unit, thereby allowing the video processor 6 to The type type such as the number of pixels of the CCD 30 incorporated in the actually connected electronic endoscope 2 can be detected. That is, the detection circuit 57 determines the type such as the number of pixels of the CCD 30 based on the difference in the number of pins of the connector 14.

  The means for detecting the type such as the number of pixels of the CCD 30 is not limited to that detected by the number of pins of the connector 14 corresponding to the type of the number of pixels of the CCD 30 and the like. The number of pixels (the number of horizontal images and the number of vertical images) may be detected from the number of waveforms of the output signals.

  Next, the configuration of the IHb processing block 44 will be described. As shown in FIG. 2, the R signal from the R memory 39r and the G signal from the G memory 39g are input to the IHb calculation circuit 61 in the IHb processing block 44, and the value of IHb is calculated. The output signal of the IHb calculation circuit 61 is input to the IHb average value calculation circuit 62 that calculates the IHb average value.

  The CCD type information detected by the detection circuit 57 is input to a region of interest setting circuit 63 for setting a region of interest, and the region of interest setting circuit 63 displays a pseudo image according to the information of the CCD type. In this case, the display area of the pseudo image is set so as to display with an appropriate size.

  Also, the information on the region of interest set by the region of interest setting circuit 63 is sent to the IHb calculation circuit 61 and the IHb average value calculation circuit 62, and IHb is calculated from pixels in the region of interest other than the invalid region.

  Specifically, the IHb calculation circuit 61 calculates the value of IHb in each pixel by performing the calculation of the following equation (1).

IHb = 32 × log ₂ (R / G) (1)
R: R image data excluding the invalid region in the region of interest G: G image data excluding the invalid region in the region of interest This expression (1) can be easily realized by a circuit, for example, input R This can be realized by calculating image data and G image data using a divider (not shown) and converting the output result using a log conversion table (not shown) configured by a ROM or the like. Further, the above equation (1) may be calculated using a CPU or the like.

  The IHb calculated by the IHb calculation circuit 61 is output to the IHb average value calculation circuit 62, and the IHb average value calculation circuit 62 is invalid in the region of interest set by the region of interest setting circuit 63 with respect to the input IHb. The IHb average value is calculated by averaging in the area excluding the area. Note that the post-stage image processing circuit 51 may be color tone adjustment or color enhancement.

  The IHb calculated by the IHb calculation circuit 61 is input to the pseudo image generation circuit 64. The pseudo image generation circuit 64 generates a pseudo image to be displayed in pseudo color from the value of IHb, and outputs the pseudo image to the image synthesis circuit 65 that performs image synthesis. The pseudo image generation circuit 64 also receives a signal corresponding to the invalid area from the invalid area display circuit 69.

  The image composition circuit 65 receives the pseudo image data generated by the pseudo image generation circuit 64 and the R, G, B image data from the R, G, B memories 39r, 39g, 39b. 65 performs a process of combining both image data based on the mask signal from the region-of-interest setting circuit 63, and outputs the combined image data to the frame sequential circuit 66 that converts the combined image data into a frame sequential signal. Specifically, the image composition circuit 65 outputs R, G, B image data corresponding to the original image when the mask signal is “0”, and outputs pseudo image data when the mask signal is “1”. The image data synthesized so as to output the image data indicating the invalid area is output to the subsequent frame sequential circuit 66. In this case, the image data indicating the invalid area is displayed in an achromatic color. The frame sequential circuit 66 performs a process of outputting the R, G, and B components of the combined image data in a frame sequential manner. That is, image data of R, G, and B components is output in frame sequential order to the γ correction circuit 50 side.

  In the present embodiment, the region-of-interest information (specifically, mask signal) by the region-of-interest setting circuit 63 is sent to the γ correction circuit 50 and the subsequent image processing circuit 51, and the region around the region of interest is selected by the user. Γ correction and structure enhancement can also be performed on the original image portion. In addition, the IHb average value calculated by the IHb average value calculation circuit 62 is sent to the character superimposing circuit 52 so that the calculated IHb average value can be displayed on the monitor screen. Also in this case, display / non-display can be selected via the CPU 56 by the user's selection.

  The R, G, B image data from the R, G, B memories 39r, 39g, 39b is input to the luminance detection circuit 67 that constitutes the invalid area detector 46. The luminance detection circuit 67 detects the luminance level of the R, G, and B image data in the region of interest and outputs the detection result to the invalid region detection circuit 68.

  The invalid area detection circuit 68 detects (determines) whether or not it is an invalid area by comparing with a preset threshold value.

  The invalid area detection circuit 68 compares the luminance level detected by the luminance detection circuit 67 with two threshold values. The two threshold values are a halation detection threshold value and a dark portion detection threshold value. The halation detection threshold value is set to 200/255, and the dark portion detection threshold value is set to 20/255. Has been. Here, 255 indicates a saturation level when quantized with 8 bits.

  When the luminance level is equal to or lower than the dark portion detection threshold and when the luminance level is equal to or higher than the halation detection threshold, it is determined as an invalid area.

  The invalid area detection circuit 68 outputs the invalid area detection result to the invalid area display circuit 69 and also outputs it to the IHb calculation circuit 61, the IHb average value calculation circuit 62, and the CPU 56. Then, the invalid area display circuit 69 outputs a 0 or 1 signal indicating the invalid area portion to the pseudo image generation circuit 64, and the pseudo image generation circuit 64 displays, for example, an achromatic color (gray) in the invalid area. To be.

  Also, the IHb calculation circuit 61 does not calculate IHb in the region of interest when the invalid region detection information is input from the invalid region detection circuit 68, and the IHb average value calculation circuit 62 is invalid in the region of interest. The IHb average value is calculated in the area excluding the area.

  Further, the CPU 56 counts (counts) the size (size) of the invalid area based on the invalid area detection information, and determines whether or not to perform image processing (compared to a threshold value). The user can be notified by voice from the speaker 70 connected to the CPU 56 or display on the monitor 7.

  In this embodiment, the CPU 56 has an illumination light quantity control function 56a for controlling the illumination light quantity by the diaphragm 25 to a state suitable for image processing in a state where the image process is being executed depending on whether or not the image process is being executed. It is characterized by having.

  In this case, the CPU 56 also includes an electronic shutter control function 56b for controlling the CCD driver 33 via the control circuit 40 and controlling the operation of the electronic shutter by the CCD 30 as necessary.

  The CPU 56 includes, for example, a ROM 56c as a recording means in which a control program for performing such an image processing method is written, for example, and the CPU 56 reads the control program in the ROM 56c at the time of start-up and reads the above-described control program. Such image processing is performed. Specifically, control is performed so as to perform the image processing operations of the flowcharts shown in FIGS.

  The user can instruct the monitor 7 to display a normal image (also referred to as an original image) illuminated and imaged with normal visible light by an instruction switch provided on the front panel 55 of the video processor 6 or an instruction operation from the keyboard 9. When an instruction to display an IHb image is given, the instruction signal is input to the CPU 56, and the CPU 56 performs control such as ON / OFF of image processing in the IHb processing block 44 in response to the instruction signal.

  In this case, when the user gives an instruction to turn on / off the display of the IHb image (pseudo image) or ON / OFF of the color enhancement from the switch or keyboard 9 provided on the front panel 55, the CPU 56 responds to the instruction. ON / OFF control.

  The R, G, B image data from the R, G, B memories 39r, 39g, 39b is input to the color misregistration detection circuit 47, and the correlation amount of the R, G, B image data is detected. Detects the amount of color misregistration.

  When an image freeze instruction is given, a signal is sent to the control circuit 40 so that an image with the smallest color misregistration is detected within a set time or the like, and an image of the field in which the image with the smallest color misregistration is detected is displayed. The sending and control circuit 40 prohibits writing to the R, G, B memories 39r, 39g, and 39b of the memory unit 39 and displays the image displayed on the monitor 7 as the display means and the monitor of the monitor image photographing device 8A. Set the image displayed in to a still image state.

  FIG. 4 shows a menu screen for performing various settings from the front panel 55 and the keyboard 9. By displaying the menu screen, as shown in FIG. 4A, the display size of the endoscopic image, the display size of the region of interest, the selection of Normal / Wide in the IHb range as the processed image, and the display of the average value of IHb ON / OFF, freeze level selected from 1 to 7 as shown in FIG. 4B, color shift detection by pre-freeze / color shift prevention freeze, full / light character display, average / auto / peak photometry The system can be selected and set.

  Here, the display size of the endoscopic image can be selected from, for example, large, medium, and small, and the display size of the region of interest can be selected and set from large, medium, and small. Also, when the IHb range is Normal, those with IHb values from 30 to 70 are displayed in 16 levels of pseudo-color, and when Wide, those with IHb values from 10 to 90 are displayed in 16 levels. Display in pseudo color.

  The freeze level varies the number of images to be detected for color misregistration detection. The number of images is either before or after the freeze switch is pressed, and is determined by the image captured in the memory for a predetermined time. The value of the level can be set from 1 to 7, for example, about 50 msec at level 1 and about 1 sec at level 7.

  In the color misregistration detection, pre-freezing is performed before the freeze switch is pressed and a color misregistration prevention freeze is performed after the freeze switch is pressed. In addition, the full character display displays all necessary items, and the light is displayed limited to some information. Furthermore, photometry is to adjust the light quantity of the light source so that the brightness of the endoscopic image is in a desired state. The average in photometry is adjusted so that the entire image becomes bright. Even if the image appears in the image, it is adjusted so that the resulting halation does not darken and the peak in photometry is adjusted so that halation does not occur.

  FIG. 5 shows a state in which the region of interest 7c is set at, for example, five different positions from the case of only the endoscope image display region 7a (FIG. 5A) (from the center position in FIG. 5B to FIG. 5F). And the region of interest 7c shown in FIG. 5E, for example, is set from a large state to a middle state (FIG. 5G) and small (FIG. 5H).

  In this embodiment, it is possible to set the region of interest 7c for performing image processing such as IHb processing on the endoscopic image, and when the image processing in the region of interest 7c is performed, the luminance is determined by the luminance level. An invalid area is detected (determined) as to whether or not the invalid area is inappropriate for processing. In addition, an invalid area is displayed and image processing is optimized by prohibiting or notifying image processing according to the size of the invalid area.

  Although it has been described with reference to FIG. 5 that the position and size of the region of interest 7c can be selected and set, FIG. 6 illustrates a processed image obtained by performing image processing on the region of interest 7c from a state in which the endoscope image is displayed in the endoscope image display region 7a. FIG. 6 is an explanatory diagram in the case of displaying a pseudo color image to be displayed in a pseudo color according to the value of IHb.

  For example, in a normal operation state, the endoscope image is displayed as a moving image in the octagonal endoscope image display area 7a on the display surface of the monitor 7 as shown in FIG. In addition to patient data and the like, an IHb average value display preparation display is displayed on the left side of the endoscope image display area 7a.

  Specifically, IHb = --- (indicated by 7b) is displayed, and preparations for displaying the IHb average value are made. The display of the IHb average value display preparation can be hidden by selection. It should be noted that information serving as a standard for diagnosing whether a lesion part or a healthy part (normal part) can be obtained based on the average value of IHb.

  When the user performs an instruction operation to turn on the display of the pseudo color image, for example, as shown in FIG. 6B, a pseudo image as an image processing image is displayed in the set region of interest 7c in the endoscope image display region 7a. Display a color image. In this case, when an image processed image is displayed in the region of interest 7c, the luminance level is detected, and the invalid region detection circuit 68 determines whether or not the region is an invalid region.

  If the size of the invalid area 7d is a size suitable for image processing, the monitor 7 enters a state in which the pseudo color image 7e is displayed in a portion excluding the invalid area 7d, and the invalid area 7d is displayed. Display in achromatic color. Also, the display of the IHb average value (indicated by 7f) can be performed from the display of the IHb average value display preparation in FIG. FIGS. 6B and 6C show a state in which the region of interest 7c is set to a large size. Note that, when the region of interest 7c is set to a large size as will be described later with reference to FIG. 10, it is determined whether or not to execute image processing depending on whether the invalid region 7d is 40% or less of the region of interest 7c. to decide.

  In the case of FIG. 6B, since the invalid area 7d is 40% or less of the region of interest 7c, image processing is executed, and as a result of the image processing, a pseudo color image 7e is displayed in the region of interest 7c. The display 7f of the average value of IHb is performed.

  On the other hand, in the case where the size of the invalid area 7d is greater than or equal to the size unsuitable for image processing, specifically in the case shown in FIG. 6C, the invalid area 7d exceeds 40% of the region of interest 7c. In this case, the image processing is not executed, the pseudo color image 7e is not displayed, and the display 7f of the average value of IHb is not performed. In the case of FIG. 6C, the invalid area 7d is a dark part. In this case, the invalid area 7d is mainly a dark part. The user is informed that the amount of light should be increased, and the user can optimize the image processing so that the invalid area 7d can be reduced and image processing can be performed by performing an operation in accordance with this notification. To do. In this case, the endoscope image display region 7a, the region of interest 7c, and the invalid region 7d may not be displayed.

  In addition, a color bar 7g indicating a range when displayed as a pseudo color image is displayed on the right side of the endoscope image display area 7a. In this case, it is shown in the case of a standard range (however, in FIG. 5, it is simplified and shown as Norm).

  FIG. 7A shows a display example when the region of interest 7c is set to a medium size, and FIG. 7B shows a display example when the region of interest 7c is set to a small size and dark. Show. As illustrated in FIG. 10, when the region of interest 7c is set to a medium size and a small size, if the invalid region 7d is 30% or 20% or less of the region of interest 7c, image processing is performed. % And 20%, image processing is not executed. In FIG. 7A, the invalid region 7d is 30% or less of the region of interest 7c, which is a display example when image processing is executed. FIG. 7B shows the invalid region 7d exceeding 20% of the region of interest 7c. This is a display example when image processing is not executed. Also, notification is performed, and the user can optimize the image processing by performing an operation according to the notification.

  FIG. 7C shows a case where the region of interest 7c has a large size and a ratio of the invalid region 7d is small (substantially the same as the case of FIG. 6B). 7 (D) shows an example in which the pseudo color display range is changed from Normal to Wide.

  In the present embodiment, as shown in FIG. 6B and the like, when the pseudo color image or the invalid region 7d is displayed only in the region of interest 7c set in the endoscope image display region 7a, the region of interest setting circuit 63 A mask signal is generated by the action as shown in FIG. 8 so that a processed image such as a pseudo color image can be displayed in an appropriate size even in the case of the CCD 30 having a different number of pixels. For example, when a pseudo color image is displayed as a processed image, the region-of-interest setting circuit 63 uses the detection signal from the detection circuit 57 and the CCD 30 actually used is of type 1 as shown in step S1 of FIG. If it is determined whether or not it is a type, a mask signal for type 1 is generated as shown in step S 2, and this mask signal is output to the image composition circuit 65.

  The mask signal for type 1 is “1” at the timing of displaying a processed image such as a pseudo color image, and outputs a binary mask signal that is “0” in other periods. By this mask signal, image synthesis is performed such that a processed image such as a pseudo color image is partially inserted into the original image and output to the subsequent stage. Then, a pseudo color image is partially displayed on the display surface of the monitor 7 as shown in FIG.

  On the other hand, if it does not correspond to step S1 in FIG. 8, the process proceeds to step S3 to determine whether or not the CCD 30 is of type 2. When it is determined that the type 2 type is applicable, the region-of-interest setting circuit 63 generates a type 2 mask signal and outputs the mask signal to the image composition circuit 65 as shown in step S4. Also in this case, a pseudo color image is displayed in substantially the same manner as in FIG.

  On the other hand, if the condition in step S3 is not satisfied, the process proceeds to step S5, and a mask signal corresponding to another type is generated. In this manner, even in the case of a plurality of types of CCD 30, partial display of a pseudo color image can be performed with a size appropriate for the number of pixels of the CCD 30 and the like.

  For example, in the type 1 CCD 30, if the number of pixels is 400 × 400, the size of the region of interest is large, and the position is the central portion, the central portion is 200 × 200. A binary mask signal is generated that is “1” in the pixel region (that is, ¼ size) and “0” in other periods. In the type 2 CCD 30, the number of pixels is 800 × 600, and in this case, “1” is obtained in a 400 × 300 pixel region (again a size of ¼) at the center, and the other periods. Then, a binary mask signal which is “0” is generated.

  Accordingly, in either case of type 1 or type 2, the pseudo color image is displayed at the 1/4 display size at the center of the original image or the like.

  In either case of type 1 or type 2, a mask signal corresponding to the size of the region of interest 7c is generated. FIG. 9 shows the processing content of, for example, type 1 mask signal generation. When this process starts, in step S6, the region of interest setting circuit 63 determines whether the region of interest 7c to be set or selected is large. If this is the case, the process proceeds to step S8a to generate a mask signal corresponding to the large area of interest 7c, and in the next step S9a, the threshold value of the invalid area 7d is set.

  If it is determined in step S6 that the region of interest 7c is not large, the process proceeds to the next step S7, and the region of interest setting circuit 63 determines whether the region of interest 7c is inside. If this is the case, the process proceeds to step S8b to generate a mask signal corresponding to the intermediate region of interest 7c, and in the next step S9b, the threshold value of the invalid region 7d is set.

  If it is determined in step S7 that the region of interest 7c is not inside, the process proceeds to step S8c to generate a mask signal corresponding to the small region of interest 7c, and in the next step S9c, the threshold value of the invalid region 7d is set. I do.

  As described above, in this embodiment, the threshold value is set according to the size of the region of interest 7c, and image processing is performed more appropriately, that is, so as to maintain a predetermined accuracy.

  The operation of setting the threshold value according to the size of the region of interest 7c in this way will be described with reference to FIG. As described below, the threshold value is variably set according to the size of the region of interest 7c when the region of interest 7c is set large. ) Even if the relative ratio is large, the number of pixels in the remaining area is sufficiently large. Therefore, in this case, the analysis result can be obtained with sufficiently high accuracy. Therefore, the larger the region of interest 7c is, the larger the threshold is set.

  When the image processing starts as shown in FIG. 10, the position and size of the region of interest 7c are set as shown in step S11. In this case, the user performs an input operation for setting the position and size of the region of interest 7c from the keyboard 9 or the like.

  In the next step S12, the CPU 56 determines whether or not the size of the region of interest 7c set in this way is large. If it is determined that the threshold value is large, the threshold value is set to 40% as shown in step S14a, and the process proceeds to step S15.

  On the other hand, when the CPU 56 determines in step S12 that the size of the region of interest 7c is not large, the process proceeds to the next step S13, and determines whether or not the size of the region of interest 7c is medium. And when it is judged that it is inside, as shown to step S14b, a threshold value is set to 30% and it moves to step S15.

  In step S13, if the CPU 56 determines that the size of the region of interest 7c is not medium, the process proceeds to step S14c, determines that the size of the region of interest 7c is small, sets the threshold to 20%, and proceeds to step S15.

  In step S15, the luminance detection circuit 67 performs luminance calculation for each pixel in the region of interest 7c, and sends the calculation result to the CPU 56.

  In the next step S <b> 16, the CPU 56 calculates the number of pixels using a threshold value for discriminating halation and dark portions from the luminance calculation result.

  In the next step S17, the CPU 56 determines whether or not the number of pixels in the invalid area 7d is equal to or smaller than the threshold value using the threshold values set in steps S14a, 14b, and 14c. In the determination, if the number of pixels in the invalid area 7d is equal to or smaller than the threshold, the CPU 56 turns on the image processing in the region of interest 7c and causes the image processing to be performed as shown in step S18.

  On the other hand, if it is determined in step S17 that the number of pixels in the invalid area 7d exceeds the threshold, the CPU 56 turns off image processing in the region of interest 7c as shown in step S19.

  That is, when there are many invalid areas 7d, image processing is prohibited. For this reason, when there are many invalid areas 7d, an inappropriate processing result cannot be obtained, and optimization of image processing is performed so that it is not necessary to check whether the processing result has a predetermined accuracy. I am doing. In addition to this prohibition, the CPU 56 notifies that the image processing is not appropriate as shown in step S20. For example, a notification message or notification sound that “brightness is not appropriate” is performed on the monitor 7 or the speaker 70. For this reason, the user can easily know that the image processing is not performed because the brightness is not appropriate. And it can also optimize so that image processing can be performed by adjusting a brightness.

  In the above, an example in which the number of pixels of the CCD 30 mounted on the electronic endoscope 2 mounted on the video processor 6 is different has been described. However, the present embodiment is not limited to this and is mounted by other elements as described above. It is also possible to determine the type of endoscope to be set, and to set each condition so as to perform image processing suitable for the mounted electronic endoscope.

  That is, based on the identification information 43 (see FIG. 2), when it is detected that an electronic endoscope having a different optical element such as an angle of view or an optical zoom is mounted, a display with an appropriate size is performed. Set each condition as follows. For example, when an electronic endoscope having an optical zoom function is attached, the image obtained from the CCD 30 has an overall important meaning, so that the size of the region of interest is set to be large, while the optical zoom function is set. When an electronic endoscope that is not provided is mounted, the size may be set small.

  In addition, unlike the upper gastrointestinal endoscope mainly used for gastric observation, etc., when the lower gastrointestinal endoscope used for large intestine observation, etc. is attached, it is possible to observe a relatively dark part with many lumens. The region of interest may be set large to facilitate easy image processing.

  Next, the operation of setting the endoscope apparatus 1 to the operating state and performing pseudo color display of the IHb distribution will be described with reference to FIG.

  When the endoscope apparatus 1 is turned on and set in the operating state, the CPU 56 in the video processor 6 monitors the instruction input from the keyboard 9 and the like, and the pseudo color ON instruction input as shown in step S21. It is determined whether or not

  If the pseudo color is not turned on, the original image is displayed in step S22. For example, the endoscope image is displayed as a moving image on the display surface of the monitor 7 in the state shown in FIG.

  In this embodiment, in the case of displaying the original image, the structure-enhanced image of the rear-stage image processing circuit 51 is turned on to display the structure-enhanced image. Further, in the case of pseudo color display, the structure emphasis is automatically set to OFF so that the tone of the pseudo color display does not change.

  For this reason, if the pseudo color display is once made and then the pseudo color is turned off, the structure enhancement OFF processing at the time of the pseudo color image is canceled in step S22, and the original image is displayed in the state of the structure enhancement ON. become.

  On the other hand, if it is determined in step S21 that the pseudo color is ON, the CPU 56 performs a range check in step S23. That is, it is determined whether the color assignment for displaying in pseudo color is normal (normal) or wide (wide).

  Then, the display control of the color bar with the color assignment corresponding to normal or wide is performed. In step S24, it is determined whether the mask signal is 1.

  When the mask signal is 1, the CPU 56 controls the region-of-interest setting circuit 63 to output a region-of-interest setting signal to the image composition circuit 65. Then, the pseudo image generated by the pseudo image generation circuit 64 is synthesized with the original image by the image synthesizing circuit 65 and the pseudo color process is displayed as shown in step S25, and the process proceeds to step S27. For example, as shown in FIG. 6B, a pseudo color image is displayed in the region of interest 7c in the original image of the endoscope image display region 7a. The invalid area 7d is displayed in an achromatic color. A color bar is displayed on the right side of the endoscopic image display area 7a.

  On the other hand, when the mask signal is not 1, processing for displaying the original image is performed as shown in step S26, and the process proceeds to step S27.

  After the pseudo color image display process, the CPU 56 determines whether or not the structure enhancement in the subsequent image processing circuit 51 is ON in step S27. If ON, the structure emphasis is turned OFF and the process returns to step S21.

  On the other hand, if the structure enhancement is not turned on, the structure enhancement remains off and the process returns to step S21.

  In this way (when displaying the pseudo color image), the process of automatically turning off the structure enhancement is performed to display the pseudo color image, so that the pseudo color display by IHb was performed. In this case, it is possible to effectively prevent the pseudo color display from changing due to structure enhancement.

  Details of the pseudo color process display process in step S25 are shown in FIG.

  When the display process of the pseudo color process is started, as shown in step S30, the CPU 56 determines whether it is within the region of interest 7c. If this is not the case, a normal image is displayed as shown in step S31.

  On the other hand, if it is determined in step S30 that the region is within the region of interest 7c, luminance calculation is performed by the luminance detection circuit 67 as shown in step S32.

  The result of the luminance calculation is sent to the invalid area detection circuit 68, and the invalid area detection circuit 68 determines whether or not the area is the invalid area 7d as shown in step S33. The determination result is sent to the IHb calculation circuit 61, the invalid area display circuit 69, and the CPU 56.

  If it is determined that the area is not the invalid area 7d, the IHb calculation circuit 61 performs IHb calculation as shown in step S34. Then, as shown in step S35, pseudo color display is performed in the region of interest 7c based on the IHb calculation result.

  On the other hand, if it is determined in step S33 that the area is invalid, the invalid area display circuit 69 performs invalid area display processing as shown in step S36. Further, in step S37, the size of the invalid area 7d is calculated.

  For example, the CPU 56 counts the pixels determined to be the invalid area 7d from the invalid area detection circuit 68 and calculates the size thereof. In step S38, the CPU 56 determines whether or not the calculated size of the invalid area 7d is equal to or smaller than a threshold value. In this determination, if the calculated size of the invalid area 7d is equal to or smaller than the threshold value, the image processing is continued as shown in step S39. On the other hand, when the calculated size of the invalid area 7d exceeds the threshold, the CPU 56 stops the image processing as shown in step S40.

  Further, as described above, in this embodiment, when performing image processing at the time of endoscopy, the CPU 56 controls the illumination light amount to be appropriate so that the image processing is appropriately performed. ing.

  That is, in the above description, the illumination light amount is automatically adjusted so as to obtain an appropriate brightness according to the brightness detected by the photometry circuit 42. However, when image processing is being performed, the illumination light amount is set appropriately. It is characterized in that control is performed to fix the amount of illumination light (more specifically, to fix the diaphragm 25 to the open side) so that an image processing result, that is, an accurate image processing result can be obtained. .

  Next, the operation of the illumination light quantity control at the time of endoscopy in the present embodiment will be described below with reference to FIG. As shown in FIG. 13, when endoscopy is started and signal processing by the video processor 6 is started, the CPU 56 determines whether or not image processing is being executed (image processing is turned ON) as shown in step S91. Make a decision.

  If it is determined that image processing is not being performed, the process proceeds to step S92. If it is determined that image processing is being performed, the process proceeds to step S93. In step S93, the CPU 56 controls the driving operation of the aperture motor 25a via the control circuit 40 so as to fix the aperture 25 of the light source unit 3 at the fully open position. As a modification of the processing operation for fixing the diaphragm 25 at the fully open position, the diaphragm position may be set (fixed) at a predetermined position close to the fully open side.

  On the other hand, in step S92, the CPU 56 captures the photometric result of the photometric circuit 42 via the control circuit 40, and determines whether the brightness of the image signal is appropriate.

  If the determination result in step S92 is not appropriate, the process proceeds to step S94. If it is appropriate, the process proceeds to step S95. In step S95, since the brightness is appropriate, the CPU 56 maintains the state of the aperture position and controls the operation of the aperture motor 25a that drives the aperture 25 via the control circuit 40 so as not to change the aperture position. .

  On the other hand, in step S94, the CPU 56 further determines whether the image signal is too bright. If the CPU 56 determines that the image signal is not too bright, the CPU 56 proceeds to step S96 and controls the aperture 25 to open by a predetermined amount to increase the amount of illumination light. Thereafter, the process returns to step S91. On the other hand, if it is determined in step S94 that the image signal is too bright, the CPU 56 proceeds to step S97 and controls the aperture 25 to be closed by a predetermined amount to reduce the amount of illumination light. Thereafter, the process returns to step S91.

  When the image processing is not executed in this way, the aperture amount by the diaphragm 25 is adjusted so that the brightness of the image signal becomes an appropriate value, so that the illumination light quantity with the appropriate brightness is obtained. Can be set.

  Also, in this embodiment, when image processing is being executed, the aperture 25 is fully opened and is fixed at a value near the fully open position so that the aperture 25 varies during image processing and the illumination light quantity state varies. It is possible to obtain an accurate image processing result. In other words, it is possible to reduce a subtle change in color tone that is not hindered by observation or difficult to identify, and to improve the accuracy of the image processing result.

  Thus, according to the present embodiment, a more accurate image processing result can be obtained.

  In addition, when fixing illumination light quantity as mentioned above, since the insertion part 11 of the electronic endoscope 2 is inserted in the body cavity, it may be set when it is too dark rather than when it is too bright. . For this reason, in this embodiment, the aperture 25 is fully opened and is fixed to a value close to this, so that an accurate image processing result is obtained in many cases.

  However, there is a possibility that it may be too bright as described above. Therefore, as a modification of the present embodiment, a value close to this is obtained when the aperture 25 shown in step S93 is fully opened by the determination process in step S91 in FIG. Further, as shown in FIG. 14, an image pickup control (brightness control) operation using an electronic shutter may be performed.

  Next, processing when the electronic shutter is operated will be described with reference to FIG.

  As described above, when the CPU 56 determines that image processing is being performed, the aperture 25 is fixed to a value close to the fully open aperture 25. Then, the CPU 56 controls the CCD driver 33 via the control circuit 40 and starts the operation of the electronic shutter by the CCD driver 33 and the CCD 30.

  When the operation of the electronic shutter starts, the CPU 56 determines whether the image signal is at an appropriate level from the brightness measured by the photometry circuit 42 via the control circuit 40 as shown in step S101.

  If the CPU 56 determines that the brightness is appropriate, the CPU 56 proceeds to step S102 and controls the CCD driver 33 via the control circuit 40 so as to maintain the state. That is, the CCD driver 33 outputs the CCD drive signal to the CCD 30 so as to maintain the electronic shutter state in the state determined to be appropriate in step S101.

  On the other hand, when determining in step S101 that the image signal is not at an appropriate level, the CPU 56 determines whether the image signal is too bright in step S103. If the CPU 56 determines that the image signal is too bright, the CPU 56 controls the image signal level to be dark by a predetermined amount by shortening the imaging time (charge accumulation time) of the electronic shutter in step S104. Then, the process proceeds to step S106.

  On the other hand, if it is determined in step S103 that the image signal is not too bright, the CPU 56 increases the image pickup time of the electronic shutter in step S105 so that the level of the image signal is increased by a predetermined amount. Then, the process proceeds to step S106. In step S106, the CPU 56 determines whether the imaging time by the electronic shutter is within a variable range. If it is determined that the imaging time is within the variable range, the CPU 56 returns to step S101 and repeats the same operation. On the other hand, if the CPU 56 determines that it is not within the variable range, the CPU 56 proceeds to step S107 and controls to maintain that state.

  Also in the processing of FIG. 14, if it is determined in step S101 that the level of the image signal is once appropriate, the process proceeds to step S102 and is fixed (maintained) in that state.

  According to the modified example that operates as described above, when performing image processing, the illumination light quantity is fixed, and if the brightness is not appropriate even in the fixed state, the electronic shutter function is operated to obtain the appropriate brightness. As described above, it is possible to perform image processing with high accuracy by fixing the imaging time based on the image signal.

  In the case of calculating the IHb as the blood information amount specifically described above as the image processing, a highly accurate average value of the IHb is obtained with respect to the calculated average value of the IHb, and the IHb in each pixel is obtained. When the calculated amount is displayed in pseudo color, pseudo color display with higher accuracy can be performed.

  Further, when the image processing is applied to fluorescence observation, more accurate fluorescence information can be obtained.

  Next, a second embodiment of the present invention will be described with reference to FIGS. The configuration of this embodiment is almost the same as that of Embodiment 1, but the means and method for white balance adjustment are different. The relationship between the position of the diaphragm 25 shown in FIG. 2 and the amount of illumination light supplied to the light guide 23 through the opening of the diaphragm 25 is, for example, as shown in FIG.

  When adjusting the white balance for normal observation, a white object is used. Since this white object is bright, white balance is performed with the aperture 25 considerably closed as shown in FIG. It will be in a state to end.

  On the other hand, when imaging the inside of the body cavity, for example, the insertion portion 11 in the stomach, the position of the diaphragm 25 is the half-opened B or the half-opened C included in the range R1 or the range R2 on the full open side in FIG. It becomes the position. That is, in the body cavity, the position of the diaphragm 25 is often near the position of the half-open B near the center reaching the full opening, or the position of the half-open C opened more from the vicinity of the center.

  For this reason, in the present embodiment, the iris 25 is set to a condition closer to the actual position of the iris 25 in the body cavity, and the white balance adjustment is performed under the condition, and the white ballast adjustment state is set. Maintain image processing.

  An operation for obtaining a white balance adjustment value (abbreviated as white balance value in the drawing) by white balance adjustment in this case will be described with reference to FIG. When the white balance adjustment operation starts as shown in FIG. 16, the user images a white subject as a reference with the electronic endoscope 2 as shown in step S <b> 111.

  In the next step S112, the CPU 56 controls the control circuit 40, and the control circuit 40 uses the output of the photometry circuit 42 that measures the image picked up by the CCD 30 to set the aperture of the aperture 25 by the aperture motor 25a. Adjust the light intensity to an appropriate value. The position of the diaphragm 25 in this state is normally in the vicinity of the half-open A in FIG.

  In this state, as shown in step S <b> 113, the CPU 56 acquires the white balance adjustment value for normal observation via the control circuit 40. In other words, when the R, G, B input signals are set so that these signal levels are equal to the R, G, B signal levels output by the CCD 30 in this state and output from the white balance adjustment circuit 38. The gain values for the R, G, and B signals are acquired as white balance adjustment values. The CPU 56 stores (stores) the acquired white balance adjustment value in, for example, an internal register.

  In the next step S114, the CPU 56 controls the CCD driver 33 via the control circuit 40 to operate the electronic shutter so that the output signal from the CCD 30 is 60%. That is, the CCD driver 33 applies the CCD drive signal to the CCD 30 and reads it out in a time 60% shorter than the imaging time for accumulating the signal charge by the CCD 30 when the electronic shutter is not operated, and this signal is used. To. Then, the remaining signal charges are swept away.

  In the next step S115, the CPU 56 drives the aperture motor 25a via the control circuit 40, and sets the aperture position of the aperture 25 to the half-open position B in FIG.

  In this state, the CPU 56 acquires the white balance adjustment value for image processing (1) via the control circuit 40. That is, since the level of the output signal of the CCD 30 can be lowered by the electronic shutter in step S114, even if the illumination light quantity is increased from the half-open A to the half-open B, it is input to the white balance adjustment circuit 38. The R, G, and B signal levels are substantially the same as those in step S113.

  For this reason, if the white balance adjustment value for image processing (1) is acquired in this state, the white balance adjustment value for image processing (1) can be acquired with high accuracy. The CPU 56 stores (stores) the acquired white balance adjustment value in an internal register or the like.

  In the next step S117, the CPU 56 controls the CCD driver 33 via the control circuit 40 to operate the electronic shutter so that the output signal from the CCD 30 is 30%. Thereafter, as shown in step S118, the CPU 56 drives the aperture motor 25a via the control circuit 40, and sets the position of the aperture 25 to the half-open C position in FIG.

  In this state, the CPU 56 acquires the white balance adjustment value for image processing (2) via the control circuit 40. That is, since the level of the output signal of the CCD 30 can be lowered by the electronic shutter in step S117, even if the illumination light quantity is increased from the half-open A to the half-open C, the R input to the white balance adjustment circuit 38 is achieved. , G, B signal levels are substantially the same as in step S113.

  Therefore, when the image processing (2) white balance adjustment value is acquired in this state, the image processing (2) white balance adjustment value can be acquired with high accuracy. The CPU 56 stores (stores) the acquired white balance value in an internal register or the like. In this way, in this embodiment, after obtaining white balance adjustment values for normal observation, image processing (1), and image processing (2), normal observation or image processing is performed as described in FIG. The white balance adjustment value used in the white balance adjustment circuit 38 is made appropriate in accordance with the state of.

  After the white balance adjustment is completed, the insertion portion 11 of the electronic endoscope 2 is inserted into the body cavity, imaging by the CCD 30 is performed, and an endoscopic examination operation for displaying an endoscopic image on the monitor 7 is started.

  Then, in the first step S121 in FIG. 17, the CPU 56 determines whether image processing is being executed. If it is determined that image processing is not being performed, the CPU 56 controls the white balance adjustment circuit 38 via the control circuit 40 so as to adopt the white balance adjustment value for normal observation in step S122. That is, the CPU 56 sends information on the white balance adjustment value for normal observation stored in the register or the like to the white balance adjustment circuit 38 via the control circuit 40, and the R, G, B signals in the white balance adjustment circuit 38 are transmitted. Set the gain.

  On the other hand, if it is determined in step S121 that image processing is being performed, the CPU 56 determines in step S123 whether the position of the diaphragm 25 is within the range R1. The position of the diaphragm 25 in this case is detected by a rotary encoder or the like, and the CPU 56 detects the position of the diaphragm 25 via the control circuit 40.

  If the CPU 56 determines that the position of the diaphragm 25 is within the range R1, the CPU 56 proceeds to step S124, and the CPU 56 determines the white balance adjustment value for image processing (1) by the white balance adjustment circuit 38. Control to adopt.

  On the other hand, if the CPU 56 determines in step S123 that the position of the diaphragm 25 is not within the range R1, the process proceeds to step S125, and the CPU 56 determines whether the position of the diaphragm 25 is within the range R2. I do.

  If it is determined that the position of the diaphragm 25 is within the range R2, the process proceeds to step S126, and the CPU 56 causes the white balance adjustment circuit 38 to adopt the white balance adjustment value for image processing (2). To control.

  On the other hand, if it is determined in step S125 that the position of the diaphragm 25 is not within the range R2, the process proceeds to step S127, and the CPU 56 determines that the white balance adjustment circuit 38 sets the white balance adjustment value for normal observation. Control to adopt.

  In this embodiment, when image processing is performed in this way, the white balance adjustment state using the white balance adjustment value in a state close to the actual aperture position in the state where the image processing is being performed is set. Therefore, an accurate image processing result can be obtained.

  Even in this embodiment, although it is almost difficult to identify by observation, subtle changes in color tone can be reduced, and the accuracy of image processing can be improved.

  When the white balance adjustment value for image processing (1) or the white balance adjustment value for image processing (2) is adopted according to the position of the diaphragm 25, the diaphragm 25 is set as described in the first embodiment. It is good to control so that it may not change to the position. In this case, as described in the first embodiment, fluctuations in the amount of illumination light during image processing are suppressed, and a highly accurate image processing result is obtained.

  Next, a first modification will be described. In this modification, for example, as shown in FIG. 18, white balance adjustment values are respectively acquired at five aperture positions P1 to P5 and stored in a storage unit such as a register of the CPU 56 or an EEPROM (of course, half-open B in FIG. 15). Or subdivided C or the like). Then, by interpolating these values, the white balance adjustment value at an arbitrary aperture position can be calculated.

  In this way, it is possible to set the white balance state in a more accurate state, and it is possible to display the value of the image processing result and the processed image with higher accuracy. Further, according to the present modification, it is possible to obtain an image processing result with higher accuracy by simple processing.

  Next, a second modification will be described. In this modification, even when AGC is turned on during normal observation and a bright image is observed, during image processing, AGC is turned off only in the region of interest 7c to prevent an increase in noise caused by turning on the AGC. The accuracy of processing is improved.

  The operation in this case will be described with reference to FIG. When image processing is started as shown in FIG. 19, in the first step S131, the CPU 56 determines whether the image of the input image signal is within the region of interest 7c according to the setting information of the region of interest setting circuit 63. Make a decision. If it is determined that the image of the image signal is not within the region of interest 7c, as shown in step S132, the CPU 56 performs control so that the normal image display state remains unchanged (the display is not changed).

  On the other hand, if it is determined in step S131 that the image signal is within the region of interest 7c, the CPU 56 determines whether AGC by the AGC circuit 36 is turned on via the control circuit 40 as shown in step S133. .

  If it is determined that AGC is ON, the CPU 56 sets AGC OFF for the image signal to be image-processed as an image in the region of interest 7c as shown in step S134. Then, the process proceeds to step S135.

  On the other hand, if it is determined in step S133 that AGC is OFF, the process proceeds to step S135, and a processed image is generated in the IHb processing block 44 in step S135. In the next step S136, the processed image is displayed on the monitor 7.

  According to this modified example that operates in this manner, AGC is turned off for an image signal when image processing is performed in the region of interest 7c, so that an increase in noise when turned on is reduced or It can be inconspicuous.

  In the process of FIG. 19, when image processing is ON, AGC is turned off in the region of interest 7c. However, AGC may be turned off for the entire image including only the region of interest 7c.

  In the case of fluorescence observation, the signal level of the fluorescence signal may be digitized and displayed.

  Note that embodiments, control methods, and the like configured by partially combining the above-described embodiments and the like also belong to the present invention.

  Insert into the body cavity and perform endoscopy, and if necessary, set a part of the region of interest in the endoscopic image region, calculate the value of IHb in the region of interest, Accordingly, when image processing is performed with pseudo color display or the like, the aperture amount is fixed so that the amount of illumination light does not fluctuate, so that a highly accurate image processing result is obtained and can be used effectively by diagnosis.

[Appendix]
1. 4. The endoscope image processing apparatus according to claim 3, wherein a white balance adjustment value for a substantially arbitrary diaphragm position is obtained by interpolation from a plurality of white balance adjustment values for image processing obtained by the diaphragm means.

Supplementary note 1: The white balance can be adjusted with high accuracy by simple processing.

2. The endoscope according to claim 1, wherein the image processing unit is a blood information amount calculating unit that calculates at least one of imaging and quantification by calculating a blood information amount. apparatus.

Supplementary note 2 effect: Blood information can be accurately grasped in pseudo-color imaging, and high-precision numerical values can be obtained in numerical values that obtain an average value.

3. In an endoscope image processing apparatus for processing an image signal obtained by imaging an inside of a body cavity of a subject with an endoscope,
Image processing means for performing predetermined processing on the image signal based on the signal level of the image signal obtained by the endoscope, and an auto gain control circuit (hereinafter referred to as AGC circuit) for amplifying the image signal, An image processing apparatus for an endoscope, wherein operation of the AGC circuit is prohibited during image processing by an image processing means.

Supplementary note 3 effect: Noise increase can be prevented and image processing accuracy can be improved.

4). 4. The endoscope for an appendix according to claim 3, further comprising region of interest setting means for setting a region of interest to be processed by the image processing means for an image region formed by an image signal obtained by the endoscope. Image processing device.

Supplementary note 4 effect: While the observation image other than the image processing unit is set to an appropriate luminance, an increase in noise is prevented and image processing accuracy is improved.

5). The illumination light supply means enables the fluorescence observation by the band limiting means that supplies the excitation light for fluorescence observation with band limitation, and digitizes or images the fluorescence signal amount. Endoscopic device.

Additional effect 5: high-precision fluorescence information can be obtained.

6). In an endoscope image processing apparatus for processing an image signal obtained by imaging an inside of a body cavity of a subject with an endoscope,
Image processing based on the signal level of the image signal obtained by the endoscope to perform predetermined processing on the image signal and obtain at least one of a processed image or a processing result value capable of displaying the processing result Means,
Illumination light supply means for supplying illumination light including a visible light region for obtaining the image signal;
A diaphragm means for adjusting the amount of illumination light,
Comprising
An endoscope image processing apparatus, wherein at least one of an illumination light amount and an output level of an image signal through the aperture means is controlled so that the image signal is appropriate.

Additional effect 6: A highly accurate image processing result can be obtained.

7). In an endoscope image processing apparatus for processing an image signal obtained by imaging an inside of a body cavity of a subject with an endoscope,
Image processing based on the signal level of the image signal obtained by the endoscope to perform predetermined processing on the image signal and obtain at least one of a processed image or a processing result value capable of displaying the processing result Means,
Illumination light supply means for supplying illumination light including a visible light region for obtaining the image signal;
A diaphragm means for adjusting the amount of illumination light,
Comprising
The aperture control unit controls at least one of the amount of illumination light and the output level of the image signal through the aperture unit so that the image signal is appropriate, and sets the white balance adjustment state by the white balance adjustment unit that performs white balance adjustment. An endoscope image processing apparatus that performs control to set a state substantially corresponding to a diaphragm position of the means.

Additional effect 7: A highly accurate image processing result can be obtained.

1 is an overall configuration diagram of an endoscope apparatus provided with a first embodiment of the present invention. FIG. The block diagram which shows the internal structure in FIG. FIG. 3 is a diagram showing transmission characteristics and the like of a rotation filter and an RGB filter provided in the rotation filter. The figure which shows the example of a display of a menu screen. The figure which shows the endoscopic image display area displayed on a monitor screen, and the region of interest possible by changing a display position and size. The figure which shows the example of a display which displays a process image in a pseudo color in the region of interest set to the endoscopic image display area. The figure which shows the example of a display different from FIG. FIG. 5 is a flowchart showing a processing operation for detecting a CCD type and generating a corresponding mask signal. FIG. 9 is a flowchart showing a processing operation for generating a type 1 mask signal in FIG. 8. The flowchart figure which shows the operation | movement which changes the threshold value of whether to perform the image processing in a region of interest according to the size of a region of interest when image processing is performed. The flowchart figure which shows the processing operation which displays the original image and the processed image which image-processed. FIG. 12 is a flowchart showing processing operations for displaying pseudo color processing in FIG. 11. The flowchart figure which shows the processing operation of the illumination light quantity control at the time of an endoscopy. The flowchart figure which shows the processing operation of the imaging (brightness) control using the electronic shutter performed under the fixed state of the illumination light quantity by a diaphragm in FIG. Explanatory drawing of the aperture position etc. which perform white balance adjustment in Example 2 of this invention. The flowchart figure which shows the processing operation of white balance adjustment. The flowchart figure which shows the control operation | movement with respect to the white balance adjustment circuit at the time of an endoscopy. Explanatory drawing which acquires the white balance adjustment value in a some aperture position, and calculates the white balance adjustment value in arbitrary aperture positions by interpolation. The flowchart figure which shows the control action which turns off AGC in the image area | region which is performing image processing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Endoscope apparatus 2 ... Electronic endoscope 3 ... Light source part 4 ... Video signal processing block 5 ... Image processing block 6 ... Video processor 7 ... Monitor 7a ... Endoscopic image display area 7c ... Area of interest 7d ... Invalid area 8A ... Monitor image photographing device 8B ... Image filing device 9 ... Keyboard 10 ... Scope switch 11 ... Insertion part 12 ... Operation part 13 ... Universal cord 14 ... Connector 15 ... Connector receiving part 16 ... Tip part 17 ... Bending part 18 ... Flexible portion 21 ... illumination lens 22 ... objective optical system 23 ... light guide 24 ... lamp 25 ... stop 25a ... stop motor 26 ... motor 27 ... rotation filter 28 ... RGB filter 29 ... fluorescence observation filter 30 ... CCD
DESCRIPTION OF SYMBOLS 31 ... Motor for movement 32 ... Excitation light cut filter 39 ... Memory part 40 ... Control circuit 44 ... IHb processing block 45 ... IHb processing circuit part 46 ... Invalid area detection part 47 ... Color shift detection circuit 51 ... Later stage image processing circuit 56 ... CPU
56a ... Illumination light quantity control function 56b ... Electronic shutter control function 57 ... Detection circuit 61 ... IHb calculation circuit 62 ... IHb average value calculation circuit 63 ... Region of interest setting circuit 64 ... Pseudo image generation circuit 65 ... Image composition circuit 66 ... Frame sequential circuit 67 ... Luminance detection circuit 68 ... Invalid area detection circuit 69 ... Invalid area display circuit Agent Attorney Susumu Ito

Claims (3)

In an endoscope image processing apparatus for processing an image signal obtained by imaging an inside of a body cavity of a subject with an endoscope,
Image processing based on the signal level of the image signal obtained by the endoscope to perform predetermined processing on the image signal and obtain at least one of a processed image or a processing result value capable of displaying the processing result Means,
Illumination light supply means for supplying illumination light including a visible light region for obtaining the image signal;
A diaphragm means for adjusting the amount of illumination light,
Comprising
Endoscopic image processing characterized in that when the image processing means is in an operating state, the amount of illumination light through the aperture means is controlled so that an image signal after image processing by the image processing means is appropriate. apparatus. The diaphragm means is characterized in that when the image processing means is in an operating state, the diaphragm means performs control to maintain a predetermined position and make the opening with respect to the optical path of the illumination light constant,
The endoscope image processing apparatus according to claim 1, further comprising an electronic shutter for making the signal level of the image signal appropriate.   The white balance adjustment means for adjusting white balance is provided, and the diaphragm means is controlled to obtain respective white balance adjustment values for normal observation and image processing. The endoscope image processing apparatus according to 2.

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