JPH05344528A - Outline correcting device for endoscope image - Google Patents

Abstract

PURPOSE:To obtain a sufficient diagnostic effect by setting up/changing the correction quantity of a video signal by a correction quantity setting means arranged on the outside. CONSTITUTION:An input signal is respectively delayed by delay lines 32, 33 in each picture element for instance. An output signal from the delay line 33 which is delayed by two picture elements is added to the input signal by an adder 34. The output signal of the adder 34 is inverted to 1/2 by a 1/2 inverter 35 and the output signal of the 1/2 inverter 35 is added to the output signal of the delay line 32 to obtain an outline-emphasized component. The outline- emphasized component is set up to a prescribed size by a multiplier 37 and the output signal of the multiplier 37 is added to the output signal of the delay line 32 to obtain an outline-emphasized output signal. The multiplier value of the multiplier 37 is determined by a DC voltage level inputted from a variable resistor 40 in an emphasizing level setting circuit 32. Thereby the outline emphasizing level of an outline emphasizing circuit 31 can be optionally set up by adjusting the resistor 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an endoscopic image contour correcting device capable of emphasizing a change in a specific color component.

[0002]

2. Description of the Related Art Recently, various endoscopes (referred to as electronic endoscopes in the present invention) using a solid-state image pickup device such as a charge coupled device (CCD) as an image pickup means have been proposed.

This electronic endoscope has a higher resolution than a fiberscope, is easy to record and reproduce images, and is easy to perform image processing such as image enlargement and comparison of two screens. Have advantages.

By the way, in a conventional television camera or the like, a luminance signal Y and color difference signals RY and BY are formed from imaged R, G and B color signals, and contour enhancement processing is performed on the luminance signal Y. Is performed to improve the resolution of image quality. Similarly, some electronic endoscopes are designed to perform edge enhancement. For example, in a frame sequential electronic endoscope, the amount of edge enhancement of each of the captured R, G, and B color signals is increased. It was the same.

[0005]

However, as described above, when the contour enhancement is performed only on the luminance signal Y or the same amount for each of the R, G, and B color signals, each color component has a common contour. To be emphasized. Therefore, for example, even when a specific color component characterizes a lesion, color components other than this specific color component are also edge-emphasized, and the change of this specific color component becomes inconspicuous. There is a problem that a sufficient diagnostic effect cannot be obtained.

The present invention has been made in view of the above circumstances, and it is possible to change the contour correction amount of a video signal by a correction amount setting means provided outside, so that a sufficient diagnostic effect can be obtained. It is an object of the present invention to provide a contour correction device for endoscopic images.

[0007]

In order to achieve the above object, an endoscopic image contour correcting apparatus according to the present invention comprises:
A contour correction device for an endoscopic image in which a subject image is captured by a solid-state image sensor and a video signal thereof is corrected by a contour correction means, and correction amount setting means capable of changing a contour correction amount is provided outside the contour correction means. , The contour correction amount of the video signal is changed by the external setting means.

[0008]

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

1 to 3 relate to a first embodiment of the present invention. FIG. 1 is a block diagram of an electronic endoscope, FIG. 2 is a block diagram showing a contour emphasis circuit and a emphasis amount setting circuit, and FIG. 3 is a contour. It is a wave form diagram which shows operation | movement of the emphasis circuit.

As shown in FIG. 1, the electronic endoscope 1 has an objective lens 3 for image formation housed on the distal end side of an elongated insertion part 2, and a drive circuit 5 drives the focal plane of the objective lens 3 to drive it. The solid-state image sensor 4 is provided.

A light guide 6 formed of a flexible fiber bundle is inserted into the insertion portion 2 as an illumination light transmission means. The rear end of the light guide 6 can be detachably attached to the light source device 7. A light source lamp 8 is arranged in the light source device 7, and a rotary color filter 9 composed of color transmission filters of three primary colors of red, green and blue is arranged in front of the light source lamp 8. The rotary color filter 9 is driven to rotate by, for example, a stepping motor 10. Then, the illumination light of the light source lamp 8 passes through the rotary color filter 9 and is sequentially converted into light of each wavelength of red, green, and blue, and is condensed by a condenser lens 11 to be condensed by the light guide 6.
It is designed to be incident on the rear end of. The illumination light passes through the light guide 6 and is emitted from the tip of the light guide 6, passes through the orientation lens 12, and illuminates the subject in color plane order.

Reflected light corresponding to red, green, and blue light from the subject is sequentially received by the solid-state image pickup device 4 through the objective lens 3. A signal corresponding to each pixel of the solid-state image pickup device 4 is sequentially output in the lateral direction, for example, in response to a clock signal applied from the drive circuit 5. This pixel signal is amplified by a preamplifier 13, a video signal is extracted by a sample hold circuit 14, and further γ corrected by a γ correction circuit 15, and then A / D
It is converted into a digital signal by the converter 16. This video signal is switched by the multiplexer 17 in synchronism with color plane sequential illumination, and stored in the R frame memory 18, G frame memory 19 and B frame memory 20 corresponding to red, green and blue colors in sequence. It Each frame memory 1
8, 19, and 20 are simultaneously read out in the horizontal direction at a speed matching the display device such as the color CRT monitor 30.
The D / A converters 21, 22, and 23 convert the analog signals into R, G, and B color signals.

In the present embodiment, the R, G and B color signals are respectively supplied to the R contour emphasizing circuit 24 and the G contour emphasizing circuit 2.
5. The B contour emphasizing circuit 26 performs the contour emphasizing process. In addition, each of the contour emphasis circuits 24,
The outline emphasis amounts at 25 and 26 are R emphasis amount setting circuit 27, G emphasis amount setting circuit 28, and B emphasis amount setting circuit 30, respectively.
Can be set independently by. And
R, G, which are edge-emphasized by the independently set edge emphasis amount,
The B color signal is output to the color CRT monitor 30 so that the subject is displayed in color.

Next, each of the contour emphasis circuits 24, 25, 2
6 and the respective specific configurations of the emphasis amount setting circuits 27, 28 and 29 will be described with reference to FIG.

Incidentally, each of the contour emphasis circuits 24, 25, 2
6 has the same configuration, and is represented by reference numeral 31 in FIG.
Further, the respective emphasis amount setting circuits 27, 28, 29 have the same configuration, and are represented by the reference numeral 32 in FIG.

As shown in FIG. 2, the contour emphasizing circuit 31 includes:
The first and second delay lines (DL) 32 and 33 for delaying the input signal, the adder 34 for adding the input signal and the output signals of the delay lines 32 and 33 connected in series, and the adder 34 A 1/2 inverter 35 that inverts the output signal by 1/2, an adder 36 that adds the output signal of the 1/2 inverter 35 and the output signal of the first delay line 32, and the adder A multiplier 37 for multiplying the output signal of the multiplier 36 by a predetermined magnitude, and an adder 38 for adding and outputting the output signal of the multiplier 37 and the output signal of the first delay line 32. It

On the other hand, the emphasis amount setting circuit 32 includes a power source 39.
And a variable resistor 40 connected to the power source 39, and the DC voltage divided by the variable resistor 40 is applied to the multiplication amount setting terminal of the multiplier 37.

Next, the operation of the contour emphasizing circuit 31 will be described with reference to FIG.
Will be described.

For example, the input signal as shown in (a) is delayed by the first and second delay lines 32 and 33 by one pixel as shown in (b) and (c), respectively. Second delay line 33 delayed by two pixels
The output signal (c) and the input signal (a) are added by the adder 34 to obtain the output signal (d). The output signal (d) of the adder 34 is halved by a 1/2 inverter 35 and inverted to obtain an output signal (e). Then, when the output signal (e) of the 1/2 inverter 35 and the output signal (b) of the first delay line 32 are added by the adder 36,
The contour emphasis component (f) is obtained. The contour emphasis component (f) is set to a predetermined magnitude by the multiplier 37, and is added to the output signal (b) of the first delay line 32 by the adder 38 to obtain the contour emphasized output signal ( g) is obtained.

The multiplication amount in the multiplier 37 is determined by the DC voltage level input from the variable resistor 40 of the emphasis amount setting circuit 32. Therefore, by adjusting the variable resistor 40, the outline emphasis amount in the outline emphasis circuit 31 can be arbitrarily set. The variable resistor 4
For 0, an electronic volume for microcomputer control or the like can also be used.

When the first and second delay lines 32 and 33 delay the input signal by one pixel as described above, the contour in the horizontal direction of the screen is emphasized. Further, the delay amount of the first and second delay lines 32 and 33 may be larger than one pixel, and if the delay amount is increased, the contour of the low frequency component can be emphasized. Further, by setting the delay amount of the first and second delay lines 32 and 33 to be one horizontal scanning line, the contour in the vertical direction of the screen can be emphasized. In addition, the contour emphasis circuit 31 is set to 2
Two-dimensional contour enhancement can be performed by using a combination of two types, one on the one hand to carry out contour enhancement in the horizontal direction on the screen and the other on the other hand to enhance contour in the vertical direction on the screen.

As described above, according to this embodiment, R, G, B
A contour enhancement circuit 2 for independently enhancing the contours of color signals
4, 25, 26 and the contour enhancement circuits 24, 25, 26
Since the emphasis amount setting circuits 27, 28, and 29 capable of independently setting the outline emphasis amounts in the above are provided, the outline emphasis amounts of the R, G, and B color signals can be changed to emphasize the change of a specific color component. This makes it possible to perform optimal contour enhancement according to the site to be diagnosed. For example, it is easy to make the blood vessels stand out by increasing the contour enhancement amount of the G signal, and to distinguish between a normal pink mucous membrane and a ulcer that is hyperemic by increasing the contour enhancement amount of the B signal. become. As described above, according to the present embodiment, optimum diagnosis of various lesions becomes easy.

In this embodiment, the color signals R,
Although the case of using the G and B color signals is shown, the color signals may be complementary color systems of cyan, magenta and yellow. Also, R,
Instead of providing the contour emphasis circuit for each of the G and B color signals, the contour emphasis circuit may be provided for one or two of the R, G, B color signals.

FIGS. 4 and 5 relate to the second embodiment of the present invention. FIG. 4 is a circuit diagram showing the contour emphasizing circuit, and FIG. 5 is a waveform diagram showing the operation of the contour emphasizing circuit.

In this embodiment, when the input signal (a) is applied to the base of the transistor Tr, the high frequency component of the color signal is bypassed by the capacitor C _2, so that the signal obtained on the collector side is (b). As shown, the high frequency components are emphasized. This signal (b) is transferred to capacitor C
_{1. When} added to the series resonance circuit of the coil L, the coil L
A ringing voltage as shown in FIG. The emphasis amount setting variable resistor VR includes the coil L
And the emitter voltage as shown in (d) where the high frequency component is lost in the integrating circuit of the variable resistor VR and the capacitor C ₂ . Therefore, the variable resistance V
By adjusting R, the magnitude of the ringing operation (c) is adjusted, and the sliding terminal of the variable resistor VR is adjusted as shown in FIG.
When moved in the A direction, an output signal with pre-shoot and overshoot added and contour enhancement is obtained, as shown in (e). Conversely, when moved in the B direction,
A soft output signal with a contour as shown in (d) is obtained.

Other functions and effects are similar to those of the first embodiment.

The contour emphasizing circuit is not limited to the above embodiment, and various known circuit configurations can be used.

FIG. 6 is a block diagram of an electronic endoscope according to a third embodiment of the present invention.

In this embodiment, the contour emphasis circuit 31 is inserted between the sample hold circuit 14 and the γ correction circuit 15. The amount of edge enhancement in the edge enhancement circuit 31 can be set by the enhancement amount setting circuit 32.

In this embodiment, the contour emphasizing circuit 31 is
Since the R, G, B color signals are sequentially input, this R, G, B
By switching the outline emphasis amount set by the emphasis amount setting circuit 32 in synchronization with the switching of the B color signal, R, G, B
The contours of the color signals can be emphasized by the independently set contour emphasis amounts.

In the present embodiment, the solid-state image pickup device 4
The signals corresponding to the respective pixels are sequentially output in the vertical direction, and the first and second delay lines 32,
By setting the delay amount of 33 to 1 pixel, for example, the contour in the vertical direction of the screen can be emphasized. In this case, the frame memories 18, 19 and 20 are read out in the horizontal direction as in the first embodiment.

According to this embodiment, the contour emphasizing circuit 31 and the emphasizing amount setting circuit 32 need only be one circuit each.

Other functions and effects are similar to those of the first embodiment.

The present invention can be applied not only to the frame-sequential type electronic endoscope but also to a single plate type electronic endoscope in which a color mosaic filter is arranged in front of the solid-state image pickup device. In the present invention, the color difference signals R-Y and B- are used as color signals.
It can also be applied to a device using Y, in which case R, Y formed from a luminance signal Y and color difference signals R-Y, B-Y.
The G and B color signals may be edge-enhanced by independent edge-enhancement amounts, or the luminance signal Y, the color difference signals RY,
By edge-enhancing each of BY by an independent edge-enhancing amount, the R, G, B color signals formed from the luminance signal Y and the color difference signals RY, BY are indirectly independent edges. The contour may be emphasized by the amount of emphasis.

[0035]

As described above, according to the present invention, the correction amount of the video signal can be changed by the correction amount setting means provided outside.

[Brief description of drawings]

1 to 3 relate to a first embodiment of the present invention,
FIG. 1 is a block diagram of an electronic endoscope.

FIG. 2 is a block diagram showing an outline emphasis circuit and an emphasis amount setting circuit.

FIG. 3 is a waveform diagram showing the operation of the contour emphasis circuit.

4 and 5 relate to a second embodiment of the present invention, and FIG. 4 is a circuit diagram showing a contour emphasis circuit.

FIG. 5 is a waveform diagram showing the operation of the contour emphasis circuit.

FIG. 6 is a configuration diagram of an electronic endoscope according to a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Electronic endoscope 4 ... Solid-state image sensor 24, 25, 26, 31 ... Edge enhancement circuit 27, 28, 29, 32 ... Enhancement amount setting circuit 30 ... Color CRT monitor 40 ... Variable resistance VR ... Variable resistance

Claims (1)

[Claims] 1. An endoscopic image contour correcting device for picking up a subject image by a solid-state image sensor and correcting a video signal of the subject image by a contour correcting means, wherein the contour correcting amount is changeable outside the contour correcting means. An endoscopic image contour correction device, characterized in that an amount setting means is provided so that a correction amount of the video signal can be changed by the correction amount setting means.