JP2003010113A - Electronic endoscope system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To display an artificial coloring matter sprayed color image and an ordinary color image on a same image screen in an electronic endoscope system. SOLUTION: The ordinary color image is displayed on a first display area RL of a monitor device 200 on the basis of a red picture element signal, a green picture element signal, and a blue picture element signal equivalent to one frame obtained from an endoscope. A processor displays the artificial coloring matter sprayed color image of emphasizing a blue component on a second display area RR of the monitor device 200 by reducing a signal level value of the red and green picture element signals on a specific picture element when the signal level value of the specific picture element is lower than an average signal level value of proximity surrounding picture elements.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides a solid-state image pickup device at the tip of a scope to generate a video color signal corresponding to an image of a subject such as an internal organ, and the subject is displayed on the screen of a monitor device based on the video color signal. The present invention relates to an electronic endoscope device that reproduces a color image.

[0002]

2. Description of the Related Art In recent years, electronic endoscope devices are mainly used for reproducing color images, and as a result, in the medical field using electronic endoscope devices, as a new medical examination method based on color image reproduction. Dye endoscopy and other methods have been developed. For example, as an auxiliary diagnostic method for endoscopic diagnosis, an inspection method is known in which an appropriate dye solution is applied to the inner wall of the stomach or the large intestine to emphasize the subtle unevenness of the mucous membrane and facilitate observation of its morphology. ing.

More specifically, the inner wall of the stomach and the inner wall of the large intestine show a reddish orange color as a whole, making it difficult to observe the morphology of the fine irregularities. In such a case, when a bluish dye solution that exhibits a clear color contrast to reddish orange, such as an indigo carmine solution, is spread on the mucosal wall through the forceps holes of the scope, the dye solution becomes mucosal. It tends to collect in the concave portions of the wall, but tends to be excluded from the convex portions of the mucous membrane wall, so that the subtle unevenness form of the mucous membrane wall is very easy to observe due to the color contrast.

However, in the above-mentioned dye endoscopy method, it is necessary to prepare a dye which is harmless to the human body and is inexpensive, and because the dye is spread, the examination time becomes long and the patient's pain increases. Or, there is a problem that the mucous membrane wall cannot be observed in its original state immediately after the pigment application. In order to improve this problem, recently, as disclosed in Japanese Patent Application Laid-Open No. 2001-25025, an electronic endoscope apparatus capable of reproducing a color image with a color contrast as if dye-sprayed by image processing is considered. Has been.

Specifically, the signal level value of a specific pixel is compared with the average signal level value of eight pixels around it, and when the signal level value of the specific pixel is low, the corresponding part of the subject is depressed from the surroundings. If it is determined that the red pixel signal and the green pixel signal are reduced, the pseudo dye-spraying process for emphasizing the blue color is performed by reducing the signal level values of the red pixel signal and the green pixel signal. As a result, the color image reproduced on the monitor device exhibits a color contrast as if the blue dye solution was sprinkled. It is possible to switch and display either the color image which has been subjected to the pseudo pigment application process or the normal color image on the monitor device.

However, in the electronic endoscope apparatus as described above,
Since only one of the color image that has been subjected to the pseudo-pigmenting treatment and the normal color image is displayed on the monitor device, it is not possible to make a comparison by comparing both images at the same time. In some cases, it may be difficult to make a detailed diagnosis with only one image, and an electronic endoscope apparatus capable of observing both images at the same time is desired.

[0007]

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to obtain an electronic endoscope apparatus which simultaneously displays a pseudo dye-sprayed color image and a normal color image on the screen.

[0008]

An electronic endoscope apparatus according to the present invention generates a first video color signal based on a plurality of color pixel signals for one frame obtained from a solid-state image sensor provided at the tip of a scope. First video signal generating means for generating,
Color balance changing means for changing the color balance by reducing the signal level value of a specific color pixel signal included in the color pixel signal, and a first video color signal based on the color pixel signal output from the color balance changing means. Second video signal generating means for generating a second video color signal having a color balance different from that of, and a first display area and a second display area are set on the same screen of the display device, and are obtained based on the first video color signal. It is most important to include a display unit capable of displaying the first reproduced color image displayed in the first display area and simultaneously displaying the second reproduced color image obtained based on the second video color signal in the second display area. Characterize.

In the above electronic endoscope apparatus, the first image memory for temporarily storing the color pixel signal for one frame obtained from the solid-state image pickup device and the color pixel signal output from the color balance changing means are stored. A second image memory for temporarily storing.

In the above electronic endoscope apparatus, the color pixel signals include the primary color red pixel signal, the green pixel signal and the blue pixel signal, and the second video signal generating means has the signal level of the red pixel signal and the green pixel signal. By reducing the value, a second color video signal having a relatively high blue signal level value is generated.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a first electronic endoscope apparatus according to the present invention.
It is a block diagram showing an embodiment. The electronic endoscope device is
A scope 10 having a flexible tube 20, a processor 100 detachable from the scope 10, and a monitor device 200 connected to the processor 100 are provided.

A light guide member 12 formed of an optical fiber bundle is inserted into the scope 10 up to the tip 20a of the flexible tube, and the base end of the light guide member 12 is attached to the processor 100 when the scope 10 is attached to the processor 100. Is optically connected to the light source 102 provided in the. The light source 102 is a white light source lamp such as a xenon lamp or a halogen lamp.

A diaphragm 112 is provided on the light emitting side (left side in the figure) of the light source 102. The diaphragm 112 has its opening adjusted by a diaphragm adjusting circuit (not shown), whereby the illumination light supplied to the light guide member 12 is supplied. The amount of light is appropriately adjusted.

In the present embodiment, since the field sequential method is adopted to reproduce a color image, a rotary color filter 114 is provided further on the light guide member 12 side of the diaphragm 112. The color filter 114 has a disk shape, and a red filter that transmits only a red light component included in white light, a green filter that transmits only a green light component, and a blue filter that transmits only a blue light component are arranged in the circumferential direction. They are evenly spaced along. A light blocking area is provided between the color filters. The color filter 114 is rotated at a constant speed, and the white illumination light supplied from the light source 102 passes through the respective color filters to become red (R) illumination light, green (G) illumination light, and blue (B) illumination light. Converted sequentially.

Red illumination light that has passed through the color filter 114,
The green illumination light or the blue illumination light is condensed on the incident end face 12a of the light guide member 12 by the condenser lens 116,
Further, it is guided to the flexible tube tip portion 20a by the light guide member 12. By rotating the color filter 114 at a constant speed in this manner, red illumination light, green illumination light, and blue illumination light are intermittently emitted from the flexible tube distal end portion 20a for a certain period of time, and a subject located in front of it is emitted. For example, the inner wall X of the digestive organ is sequentially illuminated with the illumination light of each color.

An image sensor 14 composed of a solid-state image sensor, such as a CCD, is provided at the flexible tube tip portion 20a, and this image sensor 14 is combined with an objective lens system 16. The three-color illumination light is reflected by the subject and imaged on the light receiving surface of the CCD by the objective lens system 16. While the subject is illuminated by the illumination light of each color, the image sensor 14 produces an analog electrical signal for one frame of the optical subject image of each color,
That is, it is photoelectrically converted into an analog pixel signal, and this analog pixel signal is converted into an analog image signal in the subsequent light-shielding period.
Read from. As a result, the analog pixel signals corresponding to the respective color illumination lights are sequentially read out for one frame.

The analog pixel signals of the three colors read from the image sensor 14 are sequentially input to the CCD process circuit 120 of the processor 100, and here, the processing according to the characteristics of the image sensor 14 and the optical characteristics of the scope 10, for example, is performed. Clamp processing, sample hold processing, gamma correction processing, white balance correction processing, contour enhancement processing, amplification processing, and the like are performed. The three-color analog pixel signals processed by the CCD process circuit 120 are sent to the A / D converter 122, where they are converted into, for example, 8-bit digital pixel signals, and then written into the frame memory 124 and temporarily stored. To be done. Therefore, only one frame of red digital pixel signal, green digital pixel signal and blue digital pixel signal are stored in the frame memory 124.

The digital pixel signal for one frame is the number of pixels of pixel data according to a signal level value represented by, for example, 256 gradations for each of a large number of pixels arranged in a matrix on the light receiving surface of the image sensor 14. This signal level value includes luminance information and color density information on the three primary colors of light. The higher the signal level value, the higher the brightness (brighter) and the lower the color density (the lighter the color).
It is shown that. When an uneven subject is imaged, since the concave portion is darker than the surroundings, the signal level value of the pixel corresponding to the concave portion is relatively small, and conversely, the signal level value of the pixel corresponding to the convex portion is relatively small. Grows to.

In FIG. 2, one frame of red digital pixel signals stored in the frame memory 124 is arranged in an m × n matrix to form 8-bit red pixel data r.
_{11 to} r _mn , and each red pixel data r ₁₁
˜r _mn indicates the level value of the corresponding red pixel signal. Figure 2
As shown in, the reading of the individual red pixel data from the frame memory 124 is performed according to the line reading direction and the pixel reading direction. Specifically, the red pixel data r _{11 to} r _1n included in the first line are read pixel by pixel along the pixel reading direction, and when the reading of all pixel data of the first line is completed, the red line data is written in the second line. The included red pixel data r _{21 to} r _2n are read out pixel by pixel along the pixel reading direction. Similarly, red pixel data up to the m-th line is read.

After the red pixel data r _{11 to} r _mn has been read, a predetermined time has passed and then the green pixel data g _{11 to} g _mn has been read in the same manner. The data b _{11 to} b _mn are sequentially read by the same method.

Referring again to FIG. 1, the frame memory 1
A pseudo dye spraying processing circuit 130 and a memory unit 140 are connected to the subsequent stage of 24, and further six image memories, that is, a first red signal image memory (first R memory) 140r1 and a first green signal are connected to this memory unit 140. Image memory (first G memory) 140g1, first blue signal image memory (first B memory) 140b1, second red signal image memory (second R memory) 140r2, second green signal image memory (second G memory) 140g2 and a second blue signal image memory (second B memory) 140b2 are provided. The output terminal of the frame memory 124 has four memories, that is, a first R memory 140r1 and a first G memory 140g.
1, 1B memory 140b1 and 2B memory 140
b2 is directly connected, and the remaining two memories, that is, the second R memory 140r2 and the second G memory 140g2 are indirectly connected via the pseudo dye spray processing circuit 130.

In the processor 100 of the present embodiment, the red color, as if the blue dye solution is sprinkled,
There is a pseudo-dye-spraying mode that displays the pseudo-dye-dispersed color image in which the color balance of green and blue is changed, and a normal color image that does not change the color balance in parallel, and a normal mode that displays only the normal-color image. Either one can be selected, and the mode selection is set by a mode switch SW of the operation panel 118 provided on the surface of the processor 100 or a predetermined key KEY of an external input device (here, keyboard) 300. In the initial state immediately after turning on the power, the normal mode is automatically selected.

When the normal mode is selected, each color pixel data read from the frame memory 124 is directly stored in the three memories 140r1, 140g1, 140.
Each of the other three memories 140r written in b1
It is not written in 2, 140g2, 140b2. That is, the red pixel data for one frame is stored in the first R memory 14
0r1, the green pixel data for one frame is stored in the first G memory 140g1, and the blue pixel data for one frame is subsequently stored in the first B memory 140b1.

The first R memory 140r1 and the first G memory 1
40g1 and 3 stored in the 1B memory 140b1
Color pixel data is stored in these memories 140r1 and 140g.
1, 140b1 are read simultaneously and the D / A converter 1
It is converted into an analog signal by 42 and sent to the video process circuit 144. The video process circuit 144 includes a color encoder, in which a luminance signal, a color difference signal, and a chroma signal obtained by modulating the color difference signal are generated from a three-color analog pixel signal, and an NTSC in which the luminance signal, the chroma signal, and the synchronization signal are further multiplexed. An analog video color signal such as a standard composite video signal is generated.

The analog video color signal is processed by the processor 1.
00 to the monitor device 200. Monitor device 2
In 00, a color subject image is reproduced in the normal color image display area on the screen based on the analog video color signal. The color image reproduced here has a color balance very close to the color balance when the subject illuminated by white light is viewed with the naked eye.
White balance adjustment is done in 4.

An external input device 300 such as a keyboard and a mouse is connected to the processor 100, and character information such as a patient name input from the external input device 300 and an examination date and time obtained from a timer circuit (not shown) is stored in the system control circuit 150. Is converted into a character pattern signal and output to the video process circuit, where it is added to the three-color pixel data. As a result, the character information is displayed on the screen of the monitor device 200 together with the reproduced color image of the optical subject image.

On the other hand, when the pseudo dye spraying mode is set, the red pixel data, the green pixel data and the blue pixel data are stored in the three memories 140r1 and 140g1.
And 140b1 as well as the second B memory 140b2
And the pseudo pigment application processing circuit 130. In the pseudo dye spraying processing circuit 130, for each color pixel data, of all the pixels, the signal level value of the pixel having a signal level value lower than the average signal level value of the neighboring pixels adjacent thereto is reduced. The red pixel data and the green pixel data that have been subjected to the pseudo dye spraying process are written in the second R memory 140r2 and the second G memory 140g2 that are connected to the pseudo dye spraying processing circuit 130, respectively, but the blue pixel that has undergone the pseudo dye spraying process. No data is written to either. The blue pixel data output from the frame memory 124 is input to the second B memory 140b2 without any processing.

The video process circuit 144 includes a first R memory 140r1, a first G memory 140g1 and a first B memory 140r1.
A first color video signal is generated based on the 3-color pixel data read from the memory 140b1, and a first color video signal is generated based on the 3-color pixel data read from the second R memory 140r2, the second G memory 140g2, and the second B memory 140b2. A two-color video signal is generated, and the monitor device 200
A normal color image and a pseudo dye-sprayed image that has been subjected to a color balance changing process described later are displayed in parallel.

As described above, in the pseudo dye-sprayed image displayed on the screen of the monitor device 200, the blue component is relatively emphasized by suppressing the red component and the green component in the pixels corresponding to the recessed portion and the depressed portion, It is a reproduced color image that is obtained when a blue dye solution that exhibits a clear color contrast with respect to a reddish orange color solution such as an indigo carmine solution is applied to a subject, and unevenness can be easily observed. In particular, a pixel having a signal level value lower than that of the surrounding area has a higher degree of enhancement, so that the color contrast is increased and subtle unevenness such as the inner wall of the stomach or the inner wall of the large intestine can be emphasized.

The system control circuit 150 is a microcomputer for controlling all operations of the processor 100, including a central processing unit (CPU), a read only memory (ROM) for storing programs and parameters for executing various routines, A writable / readable memory (RAM) for temporarily storing data and the like, and an input / output interface (I / O) are provided.

The timing generator 152 generates various control clock pulses based on the basic clock pulse obtained from the system control circuit 150,
Each circuit of the scope 10 and the processor 100 is operated by these control clock pulses. Specifically, reading of analog pixel signals from the image sensor 14, processing of the CCD process circuit 120, and A / D converter 1
22 sampling, and writing / reading of pixel data to / from each memory of the frame memory 124 and the memory unit 140 is controlled.

The operation panel 118 is attached to the outer wall surface of the housing of the processor 100, and in addition to the above-mentioned mode changeover switch SW, a switch for manually adjusting the white balance, the amount of light, etc., and a switch for setting various modes. It has a plurality of. Moreover, the power supply circuit 15 is provided on the side thereof.
A main power button 156 for switching ON / OFF of No. 4 is provided. The power supply circuit 154 is connected to a commercial power supply (not shown), and when the main power supply switch 156 is turned on, power is supplied to each circuit of the processor 100, the light source 102 and the scope 10, and the processor 100 and the scope 10 are in an operable state.

The pseudo dye spray processing circuit 130 is a programmable integrated circuit, for example, a PLD (Programmable Log).
ic Device), so-called spatial filtering in which the signal level value of a specific pixel at the center is a value obtained by weighting a specific pixel and the signal level values of surrounding 8 pixels close to the specific pixel Perform processing.

With reference to FIG. 3, the pseudo pigment application processing circuit 1
The configuration and operation of 30 will be described in detail. FIG. 3 is a block diagram showing in detail the circuit configuration of the pseudo dye application processing circuit 130.

The pseudo dye spray processing circuit 130 includes two one-line delay circuits D1 and D2 connected in series with each other.
Equipped with. The input terminal of the first one-line delay circuit D1 is connected to the output terminal of the frame memory 124, and the output terminal thereof is connected to the input terminal of the second one-line delay circuit D2. When the red pixel data, the green pixel data, or the blue pixel data is input, each one-line delay circuit D1 and D2 delays and outputs each line by a time corresponding to the transfer time for one line.

The output terminal of the frame memory 124 has a set of one pixel delay circuits DL1 connected in series with each other.
And DL2 are connected. First one pixel delay circuit DL
The first input terminal is connected to the output terminal of the frame memory 124, and the output terminal is connected to the input terminal of the second one-pixel delay circuit DL2. Each one pixel delay circuit DL1 and D
When the red pixel data, the green pixel data, or the blue pixel data is input, L2 delays and outputs each pixel by a time corresponding to the transfer time of one pixel.

Similarly, the third one-pixel delay circuit DL3 and the fourth one-pixel delay circuit DL4 are sequentially connected to the output terminal of the first one-line delay circuit D1, and the second one-line delay circuit D2 is connected. The output terminal has a fifth one-pixel delay circuit DL5
And a sixth one-pixel delay circuit DL6 are connected in order, and the respective one-pixel delay circuits DL3, DL4, DL5 and DL6 output each color pixel data with a delay corresponding to a transfer time for one pixel.

[0039] When the frame memory 124 the red pixel data r ₁ in the order as described above from 1 to r _mn (see FIG. 2) is read, the pseudo dye spraying processing circuit 130 is input one by one pixel. For example, in the stage from the output terminal of the frame memory 124 is a red pixel data r ₃ 3 is input, the sum of the coefficient unit pixel data r ₁₁ to 1311, r _13, r ₃₁ and r ₃₃ are the pixel data in the coefficient multiplier 1312 r ₁₂ , r ₂₁ , r
The sum of ₂₃ and r ₃₂ is input to the coefficient unit 1313 as pixel data r ₂₂ .

That is, coefficient units 1311, 1312 and 1
The nine red pixel data respectively input to 313 are
The 3 × 3 matrix red pixel data extracted from the red pixel data arranged in the m × n matrix shown in FIG. 2 is configured, and the red pixel data input to the coefficient unit 1313 is , Coefficient units 1311 and 131
It is surrounded by the red pixel data input to No. 2. In other words, the eight pieces of red pixel data r ₁₁ , r ₁₂ , r ₁₃ , r ₂₁ , r ₂₃ , r ₃₁ , input to the coefficient units 1311 and 1312.
r ₃₂ and r ₃₃ become the neighboring surrounding pixel data for the red pixel data r ₂₂ input to the coefficient unit 1313.

A coefficient unit 131 is provided after each one-pixel delay circuit.
Is provided, and this coefficient unit 131 has a fixed value of "-1/8".
Is set as a weighting coefficient for the first coefficient unit 1311
And a second coefficient unit 1312 and a third coefficient unit 1313 to which the weighting coefficient “1” is set. The first coefficient unit 1311 includes an output terminal of the frame memory 124, a second one-pixel delay circuit DL2, and a second one-line delay circuit D.
The signal obtained by adding the outputs from the second and sixth one-pixel delay circuits DL6 is input, and the weighting coefficient “−1/8” is input to this input.
And outputs to the adder 133. Second coefficient unit 13
12 includes a first one-pixel delay circuit DL1, a first one-line delay circuit D1, a fourth one-pixel delay circuit DL4 and a fifth
A signal obtained by adding the outputs from the one-pixel delay circuit DL5 is input, and this input is multiplied by the weighting coefficient “−1/8” and output to the adder 133. The third coefficient unit 1313 has a third
The output of the one-pixel delay circuit DL3 is input, and this input is multiplied by the weighting coefficient '1', that is, the adder 13 with the same value.
Output to 3. Each coefficient unit 1311, 1312, 1313
The input pixel data of is updated in the pixel reading order every transfer time of one pixel. In the adder 133, the coefficient units 1311, 1
All the outputs of 312 and 1313 are added, and the result is output to the clipping circuit 134.

In this way, the two one-line delay circuits D1
And D2, the six one-pixel delay circuits DL1 to DL6, the coefficient unit 131, and the adder 133 calculate the difference ΔR between the signal level value of the central pixel and the average signal level value of its neighboring pixels. That is, as shown in FIG. 2, 3 ×
If the level values of the red pixel data of 9 pixels represented by the matrix of 3 are r ₁₁ , r ₁₂ , ..., R ₃₂ , r ₃₃ , respectively, these signal level values are respectively multiplied by the weighting factors. , The sum is calculated. At this time, the signal level value r ₂₂ of the central pixel is always multiplied by the weighting coefficient “1”, and each signal level value of the adjacent surrounding pixels has a negative weighting coefficient “−1 /”.
8'is multiplied. As a result, the red pixel data r ₂₂ of the central pixel and the red pixel data r ₁₁ , r of the adjacent surrounding pixels
Red difference data ΔR from the arithmetic mean value of ₁₂ , r ₁₃ , r ₂₁ , r ₂₃ , r ₃₁ , r ₃₂ and r ₃₃ is calculated. The green color difference data ΔG and the blue color difference data ΔB are calculated in the same manner.

The clip value of the clip circuit 134 is set to 0, and whether the difference data ΔR (or ΔG, ΔB) is positive or negative is determined. If the difference data ΔR is greater than or equal to the clip value 0, the output value is 0. If the difference data ΔR is less than the clip value 0, that is, a negative value, the difference data ΔR that is the input value is output as it is. To be done. Thus, the two one-line delay circuits D1 and D2, the six one-pixel delay circuits DL1 to DL6, the coefficient unit 131, and the adder 1
The 33 and the clipping circuit 134 have a function as a comparison unit that compares the signal level value of the specific pixel with the average signal level value of the adjacent surrounding pixels.

The density coefficient k is set in the coefficient unit 136 by the system control circuit 150, and the clipping circuit 1
When the difference data ΔR (ΔG, ΔB) or 0 output from 34 is input to the coefficient unit 136, the density coefficient k is added to the input value.
Are multiplied and output to the adder 138.

When the normal mode is set, the density coefficient k is'
It is set to 0 ', and is set to an appropriate positive value, for example,' 20 'when the pseudo dye spraying mode is set. Clip circuit 13
Since the output of 4 is the difference data ΔR or 0 which is a negative value, the output of the coefficient unit 136 is a negative value or 0. The adder 138 has the output of the coefficient unit 136 and the one-pixel delay unit D
The output of L3 is input, and the sum of both is output.

The output from the adder 138, that is, the red pixel data R _ij and the green pixel data G _ij output from the pseudo dye spraying processing circuit 130 are expressed by the following equations (1) to (2). The adder 138 has a function as a color balance changing unit that changes the signal level value of each color pixel signal. The parameters i and j are conditions 1 ≦ i ≦ m,
It satisfies 1 ≦ j ≦ n.

[0047]

[Equation 1]

When ΔR <0, the data'k · ΔR 'to be added to the input red pixel data r _ij is a negative value as described above, so the output red pixel data R _ij is the input red pixel data r _ij. The level value is reduced. This also applies to the output green pixel data G _ij .

As described above, when the pseudo pigment application mode is selected and the red signal level value of the central pixel in the pseudo pigment application processing circuit 130 is lower than the pixel average value of the adjacent peripheral pixels (ΔR <0). Is determined to be a portion corresponding to the concave portion of the subject, and the red signal level value of the central pixel is reduced and output. On the other hand, when the red signal level value of the central pixel is the same as or higher than the pixel average value of the adjacent surrounding pixels (ΔR ≧ 0), it is determined to be a portion corresponding to the flat portion or the convex portion of the subject, and the signal of the central pixel The level value is output without any change. Such pseudo dye application processing is also performed on the green pixel data.

Therefore, when the pseudo pigment application mode is selected, when the image of a subject having irregularities is picked up, the levels of the red and green components are reduced only in the pixels corresponding to the depressions, and the level of the blue component is relatively high. The reproduced color image is enhanced, and it looks as if the blue dye solution is sprinkled.

In particular, the larger the absolute value of the difference data ΔR, ΔG, that is, the larger the depression amount at the portion corresponding to the pixel, the value'k · ΔR 'or'k · ΔG' to be subtracted from the signal level value. The absolute value of becomes larger, and the blue component of the corresponding portion in the reproduced color image is further emphasized.
When the blue dye solution is actually spread, the deeper the recesses, the greater the amount of the dye solution accumulated therein, and thus the blue density also becomes high in the reproduced color image. Therefore, the reproduced color image obtained by the pseudo dye spraying process in the present embodiment can be regarded as very close to the reproduced color image obtained when the dye solution is actually sprayed.

FIG. 4 is a timing chart showing the input / output timing (writing / reading timing) of each color pixel data with respect to each memory of the memory section 140 in the pseudo dye dispersion mode. One frame of red pixel data, green pixel data, and blue pixel data are intermittently and sequentially output from the frame memory 124 (FIG. 4A).
reference). R1, G1 and B1 shown in the figure are color pixel data associated with each other to generate a video color signal for one frame. The red pixel data R1 for one frame is input and written in the first R memory 140r1 (see FIG. 4B), and the green pixel data G1 output after a predetermined time is input and written in the first G memory 140g1. (See FIG. 4C). Further, the blue pixel data B1 output after a predetermined time is input to and written in the first B memory 140b1 (see FIG. 4D). From each of the memories 140r1, 140g1 and 140b1, color pixel data R1, G1 and B relating to the same pixel.
1 is simultaneously read and output (see FIG. 4 (e)). When the color pixel data R2, G2 and B2 of the next frame are input to the memories 140r1, 140g1 and 140b1, the data in the memories are updated.

On the other hand, the red pixel data R1 'is input to the second R memory 140r2 with a delay of the time t required for the pseudo dye dispersion processing (see FIG. 4 (f)). The red pixel data R1 ′ is obtained by subjecting the red pixel data R1 output from the frame memory 124 to pseudo dye spraying processing. Similarly, the second G memory 140g2 also stores the green pixel data G1 ′ that has been subjected to the pseudo dye application processing (see FIG. 4G). The blue pixel data B1 which is the output value of the frame memory 124 is directly written in the second B memory 140b2 (see FIG. 4 (h)). Therefore, from each of the memories 140r2, 140g2, 140b2, the color pixel data R1 ′, G1 ′ and B1 relating to the same pixel are simultaneously read and output (see FIG. 4 (i)).

FIG. 5 is a timing chart showing the output timing of the color pixel signal output from each memory and the generated video color signal, and FIG. 6 is the monitor device 200.
It is a figure which shows the screen of FIG. Note that FIG. 5 shows each timing in a non-interlaced format for convenience.

The monitor device 200 is, for example, a CRT,
On the screen AREA, a first display area RL for displaying a normal color image, a second display area RR for displaying a pseudo dye-spraying color image located on the right side thereof, and a black bordering them The level region RW is set. N
In the TSC system, the screen AREA is first scanned with odd-numbered horizontal scan lines from the left side of the screen and then with even-numbered horizontal scan lines.

Specifically, the first R memory 140 will be described.
r1, the first G memory 140g1 and the first B memory 14
0b1 sets the color pixel data R, G and B of the Mth line to D
When it is output to the video process circuit 144 through the A / A converter 142, the video process circuit 144 corresponds to the M-th color image corresponding to the normal color image based on the color pixel data.
A first video color signal V _{M for the line} is generated (FIG. 5).
(See (a)). When the output of the color pixel data R, G, and B of the Mth line is completed, immediately after that, the second R memory 140 is output.
r2, second G memory 140g2 and second B memory 14
A second video color signal V _M ′ of the Mth line corresponding to the pseudo dye-spray color image is generated based on the output of the color pixel data R ′, G ′ and B of the Mth line from 0b2 (FIG. 5 ( See b)).

FIG. 5C shows the output timing of the analog video color signal output from the video process circuit 144. As the video color signal for one line, the black level signal V _B corresponding to the black level region RW is first output during the period α, and then the first video color signal V _M and the second video color during the periods β and γ. The signal V _M 'is sequentially output, and the black level signal V _B is output during the subsequent period δ. A black level signal that should serve as a boundary line is output between the period β and the period γ.

Therefore, when such a video color signal is output, as shown in FIG. 6, black areas R are provided at both ends of the screen.
W appears, and the normal color image and the pseudo dye-spraying color image are displayed in the first display region RL and the second display region RR during that period, respectively.

The density coefficient k is automatically set to 0 when the mode changeover switch SW is OFF, that is, when the normal mode is selected, and set to a predetermined value when the mode changeover switch SW is ON, that is, when the pseudo dye spraying mode is selected. . The density coefficient k is a parameter that determines the degree to which the signal levels of the red and green digital pixel signals are reduced, and is set to '20' in the present embodiment, but it is not limited to this value and is not limited to this value. When using the endoscope device, it is possible to change the value from the external input device 300 to a value according to the operator's preference.

Changing the concentration coefficient k corresponds to using several kinds of dye solutions having different concentrations when the dye solution is actually sprayed. In other words, the simple operation of changing the concentration coefficient k via the external input device 300 produces an effect as if the concentration of the dye solution was changed and sprayed.

FIG. 7 is a flow chart showing a density coefficient setting routine executed in the system control circuit 150. The execution of this density coefficient setting routine is started by turning on the main power switch 156 of the processor 100.

First, in step S102, it is determined whether or not the mode changeover switch SW is ON. If the mode changeover switch SW is OFF, then in step S104 a predetermined key K of the external input device 300 is determined.
It is determined whether EY is ON. If either one of the mode changeover switch SW and the key KEY is ON, the pseudo dye spraying mode is set in step S106, and the density coefficient k is set to "2" in step S108.
It is set to 0 ', and the process returns to step S102. When it is determined that both the mode switch SW and the key KEY are OFF, the normal mode is set in step S110, and the density coefficient k is'in step S112.
It is set to 0 ', and the process returns to step S102.

As described above, according to the electronic endoscope apparatus of the first embodiment, the pseudo dye-sprayed color image in which the blue component is emphasized by suppressing the red component and the green component with respect to the pixel whose signal level value is lower than the surroundings. And a normal color image can be displayed side by side, and an accurate diagnosis can be made efficiently by comparing and observing both images. Incidentally, in the normal mode, the red pixel data R1 ′ and the green pixel data G1 ′ which have been subjected to the pseudo dye-spreading processing are respectively stored in the second R memory 140r2,
Since it is not written in the second G memory 140g2, the density coefficient k in the normal mode may be the same value as the density coefficient k in the pseudo dye spraying mode.

8 and 9 are views showing a second embodiment of the electronic endoscope apparatus according to the present invention. FIG. 8 is a block diagram of the entire electronic endoscope apparatus, and FIG. 9 is a color pixel for a memory section. 6 is a timing chart showing data input / output timing. The electronic endoscope apparatus of the second embodiment is different from that of the first embodiment in that the image pickup method is a simultaneous method instead of a frame sequential method, but other configurations are the same as those in the first embodiment. Therefore, the same configurations are denoted by the same reference numerals and the description thereof will be omitted.

Since the image pickup method is the simultaneous method, the rotary color filter is not provided, and the white illumination light emitted from the light source 102 is guided to the subject X as it is. Image sensor 5
14 is a CCD in which a complementary color chip filter is arranged on the light receiving surface.
The analog pixel signal read from the image sensor 514 is a complementary color signal. The analog pixel signal is converted into a digital pixel signal by the A / D converter 122 via the CCD process circuit 120 and sequentially written in the frame memory 124 for one frame. Frame memory 12
The digital pixel signal, which is the complementary color signal read from No. 4, is converted into the red color digital pixel signal, the green color digital pixel signal, and the blue color digital pixel signal of the primary colors in the RGB converter 525, and the first R memory 140r1 and the first G memory 1
40g1, 1B memory 140b1, 2B memory 14
0b2 are simultaneously output (FIGS. 9A to 9D,
(See (h)) together with the first pseudo dye spray processing circuit 527.
To the second R memory 140r2 and to the second G memory 140g2 via the second pseudo dye spraying processing circuit 529 (see FIGS. 9F and 9G).

The first and second pseudo dye spraying processing circuits 527 and 529 have the same configuration as the pseudo dye spraying processing circuit 130 of the first embodiment shown in FIG. 3, and each has a red digital pixel signal and a green digital pixel. Simultaneous pseudo-coloring processing is applied to each signal. Finally, the first R memory 140r
1, 1G memory 140g1, 1B memory 140b
1, the second B memory 140b2, the second R memory 140r2, and the second G memory 140g2 simultaneously read the red digital pixel signal, the green digital pixel signal, and the blue digital pixel signal of the same pixel respectively, and the D / A converter 1
It is output to 42 (see FIGS. 9E and 9I).

As described above, also in the electronic endoscope apparatus of the second embodiment, as in the case of the first embodiment, for pixels having a signal level value lower than that of the surroundings, the red component and the green component are suppressed and the pseudo blue component is emphasized. A dye-sprayed image and a normal color image can be displayed simultaneously. In the second embodiment, the red digital pixel signal, the green digital pixel signal, and the blue digital pixel signal are processed at the same time.
There is an advantage that the processing time can be shortened as compared with the configuration of the embodiment.

[0068]

As described above, the electronic endoscope apparatus of the present invention can simultaneously display a pseudo dye-sprayed color image and a normal color image on the screen. There is an advantage that it is possible to make a diagnosis.

[Brief description of drawings]

FIG. 1 is a block diagram showing a first embodiment of an electronic endoscope apparatus according to the present invention.

FIG. 2 is a schematic diagram showing red digital pixel signals to be input to the pseudo dye spraying processing circuit shown in FIG. 1 arranged in a matrix.

FIG. 3 is a detailed block diagram of a pseudo dye application processing circuit in the processor shown in FIG.

4 is a timing chart showing the input / output timing of each color pixel data with respect to each memory of the memory unit shown in FIG.

FIG. 5 is a timing chart showing an output timing of a color pixel signal and an output timing of a color video signal from a memory unit.

6 is a diagram schematically showing how a reproduced color image is displayed on the screen of the monitor device shown in FIG.

FIG. 7 is a flowchart showing a density coefficient setting routine executed in the system control circuit of the processor.

FIG. 8 is a block diagram showing an electronic endoscope apparatus according to a second embodiment of the present invention.

9 is a timing chart showing the input / output timing of each color pixel data with respect to each memory of the memory section shown in FIG.

[Explanation of symbols]

10 Scope 14 Image sensor 100 processors 130 Pseudo dye spray processing circuit 133,138 adder 150 system control circuit 200 monitor

Continued front page    F-term (reference) 2H040 GA03 GA06 GA10 GA11                 4C061 CC06 LL02 MM03 NN01 NN05                       SS11 SS21 TT03 WW08 WW10                 5B057 AA07 BA11 CA01 CA08 CA16                       CB01 CB08 CB16 CE08 CE17                       CH11 CH14 DB06 DB09                 5C054 CA04 CC03 EA05 EB05 ED13                       EE06 FB05 FC08 FC09 FE17                       HA12

Claims (3)

[Claims] 1. A first video signal generation unit for generating a first video color signal based on a plurality of color pixel signals for one frame obtained from a solid-state image sensor provided at the tip of a scope, and the color pixel signal The color balance changing means for changing the color balance by reducing the signal level value of the included specific color pixel signal, and the first video color signal based on the color pixel signal output from the color balance changing means A second video signal generating means for generating a second video color signal having a different color balance; and a first display area and a second display area are set on the same screen of the display device. And a second reproduction color obtained based on the second video color signal at the same time that the first reproduction color image is displayed in the first display area. An electronic endoscope apparatus comprising: a display unit capable of displaying an image in the second display area. 2. A first image memory for temporarily storing color pixel signals for one frame obtained from the solid-state image sensor, and a color pixel signal output from the color balance changing means. The electronic endoscope apparatus according to claim 1, further comprising a second image memory. 3. The color pixel signal includes a primary color red pixel signal, a green pixel signal and a blue pixel signal,
The video signal generating means generates the second color video signal having a relatively high blue signal level value by reducing the signal level values of the red pixel signal and the green pixel signal. Electronic endoscope device.