JPH10313465A - Video signal processing device - Google Patents

Abstract

(57) [Problem] To provide a video signal processing device capable of performing color correction with little change in luminance. A color difference signal is converted into an RGB signal by a color difference / RGB conversion circuit, then color corrected by a color correction circuit, further converted by an RGB / color difference conversion circuit, and a luminance signal component is converted into a luminance signal correction circuit. The luminance correction is performed so that the luminance signal level does not change before and after the color correction by the correction coefficient value of the luminance signal comparison circuit 45 that compares the luminance signal before and after the color correction by 46.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal processing apparatus provided with color correction means for performing color correction on a color signal corresponding to an image displayed on a display means.

[0002]

2. Description of the Related Art In recent years, endoscopes have been widely used for diagnosis in the medical field and for medical treatment using a treatment tool as required. FIG. 12 shows a conventional electronic endoscope apparatus 1.
Is shown. This electronic endoscope apparatus 1 has an electronic endoscope 2,
The electronic endoscope 2 is elongated, for example, a flexible insertion portion 3.
A large-diameter operation unit 4 is connected to the rear end of the insertion unit 3.

[0003] A flexible universal cable 5 extends laterally from the vicinity of the rear end of the operation section 4, and a connector 6 is provided at an end of the cable 5. The electronic endoscope 2 is connected to the light source device 7 and the video processor 8 as a video signal processing device via the connector 6 (see FIG. 13).
Are connected to a control device 9 having a built-in. Further, a color monitor 10 is connected to the control device 9.

The insertion portion 3 has a rigid distal end 11 provided on the distal end side thereof, a bendable bending portion 12 provided adjacent to the rear end of the distal end portion 11, and a rear end of the bending portion 12. A flexible portion 13 extending from the end to the front end of the operation portion 4
Are sequentially provided.

[0005] By rotating a bending operation knob 14 provided on the operation section 4, the bending section 12 is rotated.
Can be bent in the horizontal direction or the vertical direction. In addition, near the front end of the operation section 4, an insertion port 15 communicating with a treatment instrument channel (not shown) provided in the insertion section 3 is provided.

FIG. 13 shows an internal configuration of the electronic endoscope 2 and the like in FIG. As shown in FIG. 13, a light guide 17 for transmitting illumination light is inserted into the insertion section 3 of the electronic endoscope 2. The distal end surface of the light guide 17 is disposed at the distal end portion 11 of the insertion section 3 so that illumination light can be emitted from the distal end surface. In addition, the above light guide 1
The incident end side of 7 is inserted into the universal cable 5 and connected to the connector 6.

The tip 11 has an objective lens system 1
8 is provided, and a solid-state imaging device 19 is provided at an image forming position of the objective lens system 18. This solid-state imaging device 19
Has sensitivity in a wide wavelength range from the ultraviolet region to the infrared region, including the visible region. The solid-state imaging device 19 includes:
The signal lines 21 and 22 are connected.
Is inserted into the insertion section 3 and the universal cable 5 and connected to the connector 6.

On the other hand, the light source device 7 provided in the control device 9 is a lamp 2 that emits light of a wide band from ultraviolet light to infrared light.
3 is provided. As the lamp 23, a general xenon lamp, a strobe lamp, or the like can be used. The xenon lamp and the strobe lamp emit not only visible light but also ultraviolet light and infrared light.

The light of the lamp 23 is emitted from the condenser lens 2.
The light is condensed by the light guide 4, is incident on the incident end of the light guide 17, is guided to the front end face via the light guide 17, is emitted from the front end face, and illuminates the observation site and the like.

The return light from the subject (subject) such as an observation site by the illumination light is formed on the solid-state image pickup device 19 by the objective lens system 18 and photoelectrically converted.

A driving pulse from a driver 25 constituting the video processor 8 in the control device 9 is applied to the solid-state imaging device 19 via the signal line 21. The image of the subject, which is photoelectrically converted by the driving pulse, is applied. , An electric signal (video signal) corresponding to the above is read out.

An electric signal read from the solid-state image pickup device 14 is input to a preamplifier 26 provided in the control device 9 or the electronic endoscope 1 via the signal line 22. . The video signal amplified by the preamplifier 26 is converted into a digital signal by an A / D converter 27 and input to a process circuit 28. The process circuit 28 performs signal processing such as color difference color signal generation, γ correction, and white balance, and the image quality correction circuit 29
To enter.

In the image quality correction circuit 29, Y, RY,
Each of the BY color signals is input, and undergoes predetermined correction according to the magnitude of the input signal. This correction is performed by a preset value or a value set from the outside.

The color difference color signals corrected by the image quality correction circuit 29 are stored in three memories 31a, 31b and 31c.
Is stored. These memories 31a,
The color difference color signals stored in 31b and 31c are read out at the same time, converted into analog signals by a D / A converter 32, output as color difference color signals, and input to an encoder 33, which outputs an NTSC composite signal. It is output.

The color difference color signal or NTSC
The composite signal is input to the color monitor 10, and the color monitor 10 displays the observation site in color.

Further, a timing generator 34 for generating the timing of the entire system is provided in the control device 9, and the timing generator 34 synchronizes the circuits such as the driver 25.

In the diagnosis using the electronic endoscope apparatus 1, the operator diagnoses the condition of the affected part based on the image displayed on the color monitor 10. The image quality correction circuit 29 is used by the surgeon to correct the image taken by the electronic endoscope 2 for the treatment,
This is a circuit that can correct the color tone so that the affected part is more prominent.

FIG. 14 shows a color correction circuit 36 based on color difference color signals in the image quality correction circuit 29. FIG. 15 shows a case in which normal processing is performed using a color difference color signal, and color correction is performed using an RGB color signal.

In FIG. 14, the values before color correction are represented by (Y, RY,
BY), and the values after color correction are (Y ', (RY)',
(BY) '). The color correction is represented by the following equation. In this case, the color correction equation C is expressed by equation (2).

[0020]

(Equation 1) From equation (1), it can be seen that the coefficient due to the correction is not applied to the luminance signal Y ', and the luminance component is maintained before and after the correction. When the luminance signal is intentionally changed, the coefficient of the underlined part in the equation (2) may be changed.

Next, a case where color correction is performed using RGB color signals will be described. FIG. 15 is a block diagram when a normal process performs color correction using an RGB color signal in an image quality correction circuit for a color difference color signal.

The color difference / RGB conversion circuit 37 converts a color difference color signal into an RGB color signal. The color correction circuit 38 performs color correction. Then, the RGB / color difference conversion circuit 39 outputs the RGB
A color difference / RGB conversion circuit 37 for returning color signals to color difference color signals
Is inversely transformed.

The color correction is performed through these steps. The color difference color signal before color correction (before conversion from color difference color signal to RGB color signal) is (Y, RY, BY), the RGB color signal before color change is (R, G, B), The RGB color signal after color correction is (R ′, G ′, B ′), and the color difference color signal after color correction (after RGB → color difference color conversion) is (Y ′, (RY) ′, (B−
Y) '), where A ^-1 is a conversion formula from a color difference color signal to an RGB color signal, K is a color correction formula, and A is an inverse conversion formula from an RGB color signal to a color difference color signal, as follows (3) , (4),
By substituting (4) and (3) for (5), (6) is obtained by substituting (7) for K, A, and A ^-1 in (6). ).

[0024]

(Equation 2) The color correction using the RGB color signals has an advantage that there is a degree of freedom in limiting the correction range in the color difference color space.

[0025]

SUMMARY OF THE INVENTION However, RGB
As can be seen from the equation (8), the color correction by the equation (5) causes some change in luminance because a coefficient is applied to the luminance signal component. That is, when color correction is performed using the RGB color signals, the hue changes, but the luminance also changes.

A change in the luminance signal is a change in brightness, which affects the appearance. Therefore, the luminance level must be adjusted to maintain the same luminance value. It is not always good for an electronic endoscope apparatus that makes a diagnosis based on a color tone displayed on the color monitor 10 to change an undesired portion (the intention to change the hue but changes to the brightness).

(Object of the Invention) The present invention has been made in view of the above points, and provides a video signal processing apparatus capable of performing color correction with little change in luminance even when performing color correction using color signals such as RGB. The purpose is to do.

[0028]

A video signal processing apparatus having a plurality of color signals input thereto and having color correction means for correcting the color state of an image displayed on a display means by adjusting the signal levels of the color signals. And comparing a first luminance signal level in the plurality of color signals before being input to the color correction means with a second luminance signal level in the corrected plurality of color signals output from the color correction means. And correcting the luminance signal levels of the plurality of corrected color signals output from the color correction unit based on the comparison result of the luminance signal comparison unit and the color signal before color correction by the color correction unit. By providing a luminance signal correcting means for correcting to a luminance signal level, the luminance signal level does not change before and after color correction even if color correction is performed with a color signal such as RGB. In can color correction.

[0029]

Embodiments of the present invention will be specifically described below with reference to the drawings. (First Embodiment) FIGS. 1 and 2 relate to a first embodiment of the present invention, FIG. 1 shows a configuration of an image quality correction circuit according to the first embodiment of the present invention, and FIG. 2 shows a configuration of a luminance signal comparison circuit in FIG.

The first embodiment of the video signal processing apparatus according to the present invention has a configuration in which the image quality correction circuit 41 of FIG. 1 is used instead of the image quality correction circuit 29 in the video processor 8 of FIG. .

The image quality correction circuit 41 of FIG. 1 basically has a configuration in which video processing is performed using color difference color signals, and only color correction is performed using RGB color signals.

The color-difference color signal output from the process circuit 28 in FIG. 12 is input to a color-difference / RGB conversion circuit 42,
It is converted into a GB color signal. This color difference / RGB conversion circuit 4
The RGB color signals output from 2 are input to a color correction circuit 43, and color correction is performed by applying a predetermined correction formula to the RGB color signals.

RGB output from the color correction circuit 43
The color signals are input to the RGB / color difference conversion circuit 44, and the color corrected RGB color signals are converted again into color difference color signals.

The luminance signal Y before color correction output from the process circuit 28 and the luminance signal Y 'after color correction output from the RGB / color difference conversion circuit 44 are input to a luminance signal comparison circuit 45 and compared. An output signal corresponding to the set value is output.

The output signal of the luminance signal comparison circuit 45 is input to a luminance signal correction circuit 46, which corrects the luminance signal Y 'after color correction again.

Here, the color difference color signal before color correction is represented by (Y, R
-Y, BY) and the color difference color signals (Y ', (R-
Y) ′, (B−Y) ′), and the luminance signal obtained by re-correcting the luminance signal Y ′ after color correction by the luminance signal correction circuit 46 is represented by Y ″.

FIG. 2 is a block diagram showing the configuration of the luminance signal comparison circuit 45. The luminance signal Y input to one terminal A is input to the comparison circuit 48 via the time adjustment circuit 47.
This time adjustment circuit 47 is for adjusting the luminance signal Y and the luminance signal Y 'after color correction, that is, the time for signal processing. The luminance time Y ′ input to the other terminal B is input to the comparison circuit 48 as it is. The magnitudes of the two luminance signals Y and Y 'input to the comparison circuit 48 are compared here, and a correction coefficient value corresponding to the difference is output.

That is, the comparison circuit 48 calculates C = Y'-Y. When C> 0, the luminance signal Y 'after the color correction is larger than before the color correction, and when C = 0, the magnitude does not change, and when C <0, it is smaller.

According to this calculation result, the luminance signal correction value generating circuit 49 sets the correction coefficient value for decreasing the luminance signal Y 'when C <0, 1 when C = 0, and the luminance coefficient when C <0. A correction coefficient value for increasing the signal Y ′ is output to the luminance signal correction value creation circuit 49.

The luminance signal correction value generating circuit 49 uses the correction coefficient value from the luminance signal comparison circuit 45 to multiply, divide or add / subtract the color corrected luminance signal Y ′ to perform the color corrected luminance signal Y ′. ′ To generate a re-corrected luminance signal Y ″ having almost the same value as the luminance signal Y.

The color difference color signals (Y ″, (RY) ′, (BY) ′) output from the image quality correction circuit 41 are temporarily stored in the memory shown in FIG. Thereafter, the image is displayed on the color monitor 10 via a D / A converter or the like.

According to such a configuration, even when the color correction is performed using the RGB color signals, the color correction can be performed so that the magnitude of the luminance signal does not change. Therefore, the color correction enables pure color enhancement or the like without changing the luminance level, and makes it easier to detect a subtle color change as in the initial state of a lesion.

Therefore, according to the present embodiment, it is possible to perform color correction so that the magnitude of the luminance signal does not change. Therefore, after the color correction, the luminance is further adjusted to set the same luminance value. This has the effect of making it unnecessary.

(Second Embodiment) In the first embodiment, color correction has been described for the case where the input signal is a color difference color signal. On the other hand, in the present embodiment, a case will be described in which a signal processing method using an RGB color signal is used.

For example, in FIG.
8, an RGB color signal is generated, the image quality of the RGB color signal is corrected by the image quality correction circuit 51 of FIG. 3, and the output signal is temporarily stored in the memories 31a, 31b, 31c.
The signal is converted into an analog signal by the / A converter 32, and further converted into a composite signal by the encoder 33, and displayed on the color monitor 10.

The RGB color signals before color correction input to the image quality correction circuit 51 are input to a color correction circuit 52, and the color correction circuit 52 performs a predetermined correction formula to perform color correction for RGB.
Perform on color signals.

R ′ color-corrected by the color correction circuit 52
The G'B 'signal is input to the matrix circuit 53. The RGB color signals before color correction are input to the luminance signal generation circuit 54, and a luminance signal Y is generated from the RGB color signals before color correction.

The luminance signal generation circuit 55 generates a luminance signal Y 'from the R'G'B' signal after color correction. And
The two luminance signals Y and Y 'generated by the luminance signal creation circuits 54 and 55 are input to a luminance signal comparison circuit 56. This luminance signal comparison circuit 56 may have the same configuration as the luminance signal comparison circuit 45 described in the first embodiment.

The output signal of the luminance signal correction circuit 56 is input to the matrix circuit 53 via the switching circuit 57.

The image quality correction circuit 51 is provided in the switching circuit 57.
CPU data from an external device such as a CPU is input, and the correction coefficient value or CPU data selected by the switching circuit 57 is output to the matrix circuit 53.

The matrix circuit 53 corrects the RGB color signal after the color correction in accordance with the output signal from the luminance signal correction circuit 56 or the CPU data, and re-corrects the R "G".
A B ″ color signal is output.

Next, the operation of the present embodiment will be described. The luminance signal generation circuit 54 generates a luminance signal Y from the RGB color signals before color correction and outputs the luminance signal Y to the luminance signal comparison circuit 56. on the other hand,
The RGB color signals input to the color correction circuit 52 are color corrected by a predetermined correction formula and output.

The R'G'B 'signal after color correction is input to a luminance generation circuit 55 and a matrix circuit 53, and the luminance signal generation circuit 55 generates a luminance signal Y' from R'G'B 'after color correction. The two luminance signals Y and Y 'are input to the luminance signal comparison circuit 56.

In the luminance signal comparison circuit 56, comparison is performed in the same procedure as in the first embodiment, and the resulting correction value is output to the switching circuit 57. This switching circuit 57
When the output signal of the luminance signal comparison circuit 56 is selected, the correction coefficient value is output to the matrix circuit 53.

The matrix circuit 53 is a luminance signal comparing circuit 5.
Using the correction coefficient value of 6, a correction formula for raising or lowering the luminance signal without changing the hue or color balance is performed on the output R'G'B 'of the color correction circuit 41. . The output of the matrix circuit 45 maintains the level of the luminance signal Y.

By performing such an operation, the entire R
Also for a system that performs signal processing using the GB color signal, color correction is performed without causing a luminance change.

Thus, even when the color correction is performed during the diagnosis, it is possible to reduce the influence of a change in the appearance due to the change in contrast due to the change in luminance, so that it is possible to easily perform an accurate diagnosis.

When a correction for intentionally adding a luminance difference (contrast) or the like is performed, the switching circuit 57 is switched to the CPU data side by a signal from a selection means (not shown), and the CPU data transmitted from the CPU (not shown). To the matrix circuit 53. Thereby, various corrections such as changing the luminance value can be further performed.

In addition to the above, color correction may be performed by keeping the level of the luminance signal unchanged before and after color correction as follows. For example, in FIG. 4, the input signal, the output signal, and the color
U, and the color adjustment is performed under the control of the CPU while keeping the level of the luminance signal unchanged before and after color correction.

More specifically, the level of the luminance signal before color correction is detected from the input RGB signals, and the luminance signal is kept constant from that state. The other color signals are increased or decreased in accordance with the increase or decrease in the color signal of the operation in which the operation is performed so that the level of the luminance signal becomes constant.
For example, when the level of a red color signal is increased, the level of green or blue is decreased so that the luminance level is constant before and after color correction.

In this case, various choices can be made to keep the brightness level constant. As described above, for example, when the level of the red color signal is increased, either the level of green or blue may be decreased, the levels of green and blue may be decreased at the same time, or weighted and decreased. Alternatively, the operator may be able to select them.

(Third Embodiment) Next, an electronic endoscope apparatus according to a third embodiment of the present invention will be described. The present embodiment is provided with a function of automatically returning the image setting value to the standard value.

First, the background will be described with reference to FIG. FIG. 16 shows an electronic endoscope device 61 substantially similar to that disclosed in Japanese Patent Application Laid-Open No. 8-122660. The electronic endoscope device 61 includes an electronic endoscope 2, a light source device 7 that supplies illumination light to the electronic endoscope 2, and an image that performs image signal processing on the solid-state imaging device 19 of the electronic endoscope 2. A video processor 8 as a signal processing device, and a color monitor 1 for displaying a video signal output from the video processor 8
0 and an external device 62 such as an image filing device connected to the video processor 8.

The same components as those described with reference to FIGS. 12 and 13 are denoted by the same reference numerals. In the electronic endoscope device 61, a video signal of an endoscope image created by signal processing for the solid-state imaging device 19 and a video signal from an external device 62 are selectively transmitted to the color monitor 10 via a switching circuit 63. A reset switch 64 is provided on the video processor 8 side, and when an abnormality occurs in the external device 62, the endoscope image on the video processor 8 side is pressed on the color monitor 10 by pressing the reset switch 64. Forced output is enabled.

Specifically, as shown in FIG. 16, the output signal of the process circuit 28 is applied to the contact A of the switching circuit 63, and is also transmitted from the video input terminal 62A to the external device 62 through the video signal output terminal 8A. Is entered. The video signal output from the video output terminal 62B of the external device 62 is applied to the other contact B of the switching circuit 63 via the external video signal input terminal 8B, and the common contact C of the switching circuit 63 is connected to a color monitor. The video signal from the contact connected to the common contact C is output to the color monitor 10.

Normally, a contact B is connected to the common contact C of the switching circuit 63. By operating the reset switch 64 in this state, the contact A is electrically connected to the common contact C, and the solid-state imaging device 19 is viewed from the inside. The mirror image is displayed on the color monitor 10.

An electronic endoscope apparatus 61A having a video processor 8 according to the third embodiment shown in FIG. 4 is similar to the electronic endoscope apparatus 61 shown in FIG. The video signal of the endoscope image and the external device 62
And a video signal from the external device 62 are provided, and a reset switch 64 is provided on the video processor 8 side. By pressing, the endoscope image of the video processor 8 (which performs video signal processing on the solid-state imaging device 19) can be forcibly output to the color monitor 10.

As shown in FIG. 4, the output signal of the process circuit 28 is input to a color correction circuit 66 constituting an image quality correction circuit 65, and after being subjected to color correction, is input to an enhancement circuit (edge enhancement circuit) 67, Is emphasized, the switching circuit 6
3 and is input to the video signal input terminal 62A of the external device 62 via the video signal output terminal 8A.

The video signal processed by the external device 62 or reproduced and output from the image recording device of the external device 62 is output from the video output terminal 62B via the external video signal input terminal 8B of the video processor 8. Switching circuit 6
3, the common contact C of the switching circuit 63 is connected to the color monitor 10, and the common contact C
The video signal from the contact connected to the color monitor 10 is output to the color monitor 10.

Normally, the contact B is connected to the common contact C of the switching circuit 63. By operating the reset switch 64 in this state, the contact A is electrically connected to the common contact C, and the solid-state imaging device 19 is viewed from the inside. The mirror image is displayed on the color monitor 10.

The color correction circuit 66 is connected via a signal line a to a correction value setting circuit 68 for setting a correction value for color correction. The correction value setting circuit 68 is further provided on the front panel of the video processor 8 or the like. It is connected to a color tone adjustment switch 69 for adjusting the color tone, and the color adjustment can be freely adjusted by operating the color tone adjustment switch 69. The color correction circuit 66 can perform color correction without changing the luminance signal level as in the first embodiment, for example.

The contour emphasizing circuit 67 is connected via a signal line b to a correction value setting circuit 70 for setting a correction value for contour emphasis. The correction value setting circuit 70 is further provided on the front panel of the video processor 8 or the like. It is connected to an enhancement adjustment switch 71 for adjusting the outline emphasis. By operating the enhancement adjustment switch 71, the enhancement amount (the outline emphasis amount) can be freely adjusted.

The reset signal from the reset switch 64 is input to the switching circuit 63 and also to the correction value setting circuits 68 and 70.

By operating the reset switch 64, the contact A of the switching circuit 63 is forcibly made conductive with the common contact C, and the correction value setting circuit 6
The correction values 8 and 70 can be set to standard correction values.

FIG. 5 is a front view of the video processor 8 of the electronic endoscope device 61. As shown in FIG. 5, a power switch 7 is provided on the front panel of the video processor 8.
4, a signal connector receiver 75, a reset switch 64, an enhancement adjustment switch 71, a color tone adjustment switch 69, and the like.

In addition, a white balance setting switch and the like are provided. Further, a print, still video device, video disk device, or the like can be connected, and a function of hard copy or recording by a corresponding device by operating a switch for printing or recording a still image.

Next, the operation of the present embodiment will be described. When the electronic endoscope device 61A outputs a signal from the external device 62 to the output to the color monitor 10, when an abnormality or the like occurs in the external device 62, the image output to the color monitor 10 is also disturbed. In particular, the color tone is often disturbed.

At this time, by pressing the reset switch 64, the output image to the color monitor 10 is switched to the endoscope image, and at the same time, the color tone and the like are returned to the standard values. Image can be supplied.

In the above description, the state after the operation of the reset switch 64 is set to the standard value (factory default value). However, in the correction value setting circuits 68 and 70, the image quality setting state of an arbitrary color tone and contour enhancement amount is set by a setting switch (not shown). The state after reset may be set to an arbitrary value by performing an operation of setting to.

When the image is returned to the initial setting state by this reset, the color tone adjustment switch 69 and the outline emphasis adjustment switch 7 as manual image quality setting means are set.
The set value (operation value) of 1 is reset and returned to 0, and by performing a switch operation from this state, it is possible to set from the standard setting state.

In the present embodiment, a case in which color correction according to the scene under examination is performed and then the normal value (standard setting) is to be returned, or a case where a plurality of operators commonly use the electronic endoscope apparatus 61A Furthermore, even when the current image quality setting state cannot be determined due to another operator's setting, it is possible to return to the standard image quality setting state by operating the reset switch 64.

The image quality adjusting function can be similarly applied to contrast adjustment and the like in addition to the above. Further, in the present embodiment, the image output to the color monitor 10 is changed to the image of the video processor 8 by the reset switch 64, and the image quality setting state of the color correction and the outline enhancement is returned to the standard value. The image output to the color monitor 10 is not limited to this,
A reset switch for setting the image on the side and an image quality setting reset switch for returning the image quality setting such as color correction to a standard value may be provided.

Further, an initial setting reset switch or a standard state setting switch is provided to set the image quality to the standard state and to change the electrical connection state with the external device 11 to the standard electrical connection state (for example, from the external device). The image quality control can be performed, but the control may not be performed.)

In the case of these image quality setting reset switches, since the external device 11 is not abnormal, it is not necessary to switch the output to the color monitor 10 from the external device 11 to the endoscope image by operating the image quality setting reset switch. Absent.

FIG. 6 shows an electronic endoscope apparatus 61B according to a first modification of the third embodiment. This first modification is shown in FIG.
Has a switching circuit 63 'for switching, for example, four contacts A, B, C, and D, instead of the switching circuit 63 for switching between the two contacts A and B.

The contact A is connected to a video signal output terminal 8A. The video signal output terminal 8A is connected to a plurality of external devices 62-1, 62-2, 62-3 such as a VTR, a video printer, and a photographing device. The other contacts B, C, and D are connected to the respective video signal input terminals 62A, and are connected to external devices 62-1, 62-2, and 62.
-3 video signal output terminals 62B.

The other structure is the same as that of FIG. Then, by switching any one of the four contacts A, B, C, and D to the common contact E by the switching circuit 63 ', the external device 62-J connected to the contact E (J = 1 or 2
Alternatively, the video output of 3) can be output to the color monitor 10.

If an abnormality or the like occurs in the external device 62-J, the image output to the color monitor 10 is disturbed. In particular, the color tone is often disturbed.

At this time, by pressing the reset switch 64, the output image to the color monitor 10 is switched to the endoscope image picked up by the solid-state image pickup device 19 by the video processor 8 and the color tone and the like are returned to the standard values. Accordingly, a stable image can be supplied even when an abnormality occurs in the external device 62-J.

In the conventional switching circuit, the order of switching is as follows: contacts A → B → C → D → A. Therefore, if an abnormality occurs while the contact B is ON, the switch does not return to the endoscope image unless the switch is pressed three times. On the other hand, in the video processor 8, by pressing the reset switch 64, the output image can be immediately returned to the endoscope image regardless of the output image.

Although the color tone and the like are returned to the standard values in FIG. 6, the image quality correction circuit 65 such as the color correction circuit 66 in FIG. 6 as in the electronic endoscope apparatus 61C shown in FIG.
May be provided so that the endoscope image of the video processor 8 can be output by operating the reset switch 64.

Further, a configuration as shown in FIG. 7 may be employed as a second modification of FIG. In the second modification, a video signal from an external device is monitored and switched. The electronic endoscope device 61D of FIG. 7 includes a signal monitoring circuit 72 in the video processor 8 of FIG.
Monitors the video signal from the external device 62 input to the video processor 8 from the video signal input terminal 8A.

The signal monitoring circuit 72 outputs a video signal (input from the external device 62) from its first output terminal 72A, and monitors this video signal. The reset signal is output from the output terminal 72B of the.

The first output terminal 72A is connected to the contact B of the switching circuit 63, and the second output terminal 72B is connected to one input terminal of the OR circuit 73, and is connected to the other input terminal of the OR circuit 73. Is connected to a reset switch 64, and resets the switching circuit 63 by the output signal of the OR circuit 73.

If any abnormality occurs in the external device 62 during the endoscope inspection, the video signal output from the external device 62 may also become abnormal. In particular, when the output video signal is a composite signal, abnormalities such as waveform distortion, change in signal level, and discontinuity appear in the synchronization signal as well as the video signal. When the signal monitoring circuit 72 detects the abnormality (voltage level or the like), it issues a reset signal. When receiving a signal from the signal monitoring circuit 72 or the reset switch 64, the OR circuit 73 issues a switching signal, switches the switching circuit 63, and switches the output to the color monitor 10 to an endoscope image.

In this device 61D, if any abnormality occurs in the external device 62 in a situation where the operator cannot release the hand during the operation, the safety is maintained by immediately outputting a video signal independent of the external device 62. Can be. Here, the signal monitoring circuit 72 is provided for the video signal, but a monitoring means may be provided for the communication circuit as described later.

According to the second modification, in addition to the functions and effects of the third embodiment, when the signal monitoring circuit 72 detects an abnormality, the reset switch is automatically operated. It has the same action and effect as.

It should be noted that, instead of switching automatically, the reset switch 64 is operated to deviate from the allowable range of the image quality setting in the comment display frame of the color monitor 10 or the like, and operate the reset switch 64 in the standard state. Therefore, a display to the effect of resetting the image quality as necessary may be displayed.

In FIG. 7, even if the image quality correction circuit 65 is not provided, the endoscope image of the video processor 8 is displayed on the color monitor 1 by operating the reset switch 64.
0 may be output.

FIG. 8 shows an electronic endoscope apparatus 61E according to a third modification of FIG. In the third modification, a control function of a changeover switch is provided on the external device side. The electronic endoscope device 61D of FIG. 8 uses a recording device 81 as the external device 62 in the electronic endoscope device 61B of FIG.

The recording device 81 is a device having a function of electrically outputting a through signal. That is, as shown in FIG. 8, the video signal input to the video signal input terminal 81A is
A signal processing system (abbreviated simply as a path) 84A applied to the contact A of the output signal switching circuit 83 via the buffer 82;
An image quality correction circuit 85 for recording correction processing and an output detection circuit 8 for detecting a state of an output signal of the image quality correction circuit 85
6 and a path 84B applied to the contact B of the output signal switching circuit 83 through the path 6B.

The output of the image quality correction circuit 85 is also input to an image recording unit (not shown). The common contact C of the output signal switching circuit 83 is connected to the video signal output terminal 81B of the recording device 81.
The video signal output terminal 81B is connected to the contact B of the switching circuit 63 via the video input terminal 8B of the video processor 8.
It is connected to the.

The output detection circuit 86 is connected to a CP (not shown).
The switching of the output signal switching circuit 83 is controlled via U or the like.

The basic operation of the recording device 81 as an external device is the same as in the third embodiment. In addition to the basic operation, the recording device 81 performs the following operation. Output (monitor) a video signal (recorded in the image recording unit) via the path 84B
(The switching circuit 83 selects the contact B).
When an abnormality occurs in the route 84B, the route 84B
Output signal becomes abnormal.

The output detection circuit 86 for inputting the signal detects the signal and sends a detection signal to a CPU (not shown). The CPU that has received it sends a switching signal to the output signal switching circuit 83, and switches the switching circuit 83 from the contact B to the contact A.

The signal on the path 84A on the contact A side is an electric through signal and does not depend on the abnormality of the path 84B, so that a signal equivalent to the input is output. The recording device 81 as an external device can output a video signal without interruption by outputting from the path 84B through the path 84A. With this configuration, even if an abnormality occurs in the signal processing path 84B in the recording device 81 during the endoscopic inspection, the endoscope image can be output without interruption.

In this case, the recording device 8 is used as an external device.
1 has been described, but by adopting a similar configuration, an external device connected to the video processor 8 is similarly effective.

(Fourth Embodiment) Next, referring to FIG. 9, an electronic endoscope apparatus 61F having a fourth embodiment of the present invention will be described.
Will be described. The video processor 8 according to the present embodiment has a function of setting an image using an external communication terminal. The electronic endoscope device 61F of FIG. 9 further includes a communication terminal 8E for an external device in the video processor 8 of FIG.

By connecting the communication terminal 8E to the communication terminal 62C of the external device 62 'having a communication function, the video signal inputted to the external device 62' via the image quality correction circuit 65 in the video processor 8 is connected. In contrast, the color tone and the amount of contour enhancement can be adjusted from the external device 62 'side.

In the color tone adjustment and the enhancement adjustment of the video processor 8, the color tone and the amount of edge enhancement are set via the signal lines a and b according to the set values of the correction value setting circuits 68 'and 70'.

In this embodiment, the switching of the set value can be controlled as in a correction value setting circuit 68 'shown in FIG. The correction value setting circuit 70 'has the same configuration.

The communication terminals 8E and 62C are connected to the control signal line 77
And the correction value setting circuit 6 from the communication terminal 62C.
8 ', 70'. When the external device 62 'is connected, the contact 68A is turned on in FIG. At this time, the color tone and the enhancement amount can be variably set in the same manner as from the front panel of the video processor 8 by the setting signal transmitted from the external device 62 '.

A video signal is recorded by a recording device (not shown) in the external device 62 'using the video signal of the set color tone and the enhancement amount, and this video signal is output from the video signal output terminal 62B, and the switching circuit 63 Is output to the color monitor 10 through the contact B, and an endoscope image corresponding to the video signal is displayed.

When the reset signal from the reset switch 64 is sent, the contact is switched from the contact 68B to the contact 68A in FIG. 10 to forcibly release the transmission signal from the external device 62 ', and an initial setting switch (not shown) such as a dip switch Alternatively, the state is switched to a state of connection with a preset switch), and a standard color tone and contour enhancement amount determined by the initial setting switch are set.

According to the present embodiment, similarly to the third embodiment, when the external device 62 'outputs an abnormal video signal, the communication signal from the external device 62' is also disturbed. Could be. By performing the operation of turning on the reset switch 64, the contact 68B of the correction value setting circuit 68 '(and the correction value setting circuit 70') as shown in FIG.
The contact 68A (and the contact 70A (not shown) of the correction value setting circuit 70 ') is switched ON from the contact 70B (not shown) to be electrically disconnected from the external device 62'.

Then, as in the third embodiment, the video signal is output to the color monitor 10 through the contact A of the switching circuit 63 and becomes an endoscope image by the video signal processing system of the video processor 8 itself. The correction signal also has a preset value.

On the other hand, the control of the image quality setting from the external device 62 'after the reset is determined according to a response signal returned to the video processor 8 after the external device 62' is reset, for example. For example, when the video processor 8 determines that the external device 62 'is normal, the control is started, and when it is determined that the external device 62' is not normal, the state where the control from the external device 62 'is not received is maintained.

As described above, in the present embodiment, the external device 62 '
Reset switch 64 also when the
Is operated, the same operation and effect as those of the third embodiment are obtained, and the control of image quality adjustment from the external device 62 'is also released.
Even if 2 'is in an abnormal state, an endoscope image can be promptly displayed by the video processor 8.

[Supplementary Notes] A plurality of color signals are input, and in a video signal processing device having color correction means for correcting a color state of an image displayed on a display means by adjusting a signal level of the color signals, the video signal is input to the color correction means. A luminance signal comparing unit that compares a first luminance signal level of the plurality of color signals before and a second luminance signal level of the corrected plurality of color signals output from the color correction unit; A luminance signal correction unit that corrects the luminance signal levels of the corrected plurality of color signals output from the color correction unit based on the comparison result of the signal comparison unit, and corrects the luminance signal levels before the color correction by the color correction unit. And a video signal processing device.

[0120] 2. A plurality of color signals are input, and in a video signal processing device having color correction means for correcting a color state of an image displayed on a display means by adjusting a signal level of the color signals, the video signal is input to the color correction means. A first luminance signal generating means for generating a first luminance signal based on the plurality of color signals, and a second luminance signal generating means for generating a second luminance signal based on the corrected plurality of color signals output from the color correcting means. A luminance signal generating means, a luminance signal comparing means for comparing the first luminance signal and the second luminance signal, and a correction output from the color correcting means based on a comparison result of the luminance signal comparing means. A video signal processing device comprising: a brightness signal correction unit configured to correct a brightness signal level of the plurality of color signals.

3. A first signal to be created in a video signal processing apparatus having a plurality of color signals input thereto and having a color correction means for correcting a color state of an image displayed on a display means by adjusting signal levels of the color signals. Conversion means;
A second signal converter for outputting a corrected luminance signal and a color difference signal based on a plurality of corrected color signals output from the color signal corrector; and a luminance signal input to the first signal converter. Signal comparing means for comparing the corrected luminance signal output from the second signal converting means with the corrected luminance signal output from the second signal converting means based on the comparison result of the luminance signal comparing means. Luminance signal correction means for further correcting the signal level of the luminance signal thus obtained,
A video signal processing device comprising:

4. In an electronic endoscope device having an imaging unit that converts light information from a subject into an electric signal, and an image signal processing unit that performs image signal processing on the electric signal of the imaging unit, before and after color tone correction Luminance signal detection means for detecting the luminance signal of the image signal, color tone correction means for correcting the color tone of the video signal, luminance signal comparison means for comparing the luminance signals before and after the color tone correction means, and color correction by the output of the luminance signal comparison means. An electronic endoscope apparatus comprising: a correction unit that corrects a subsequent color signal; performs color tone correction with RGB color signals; and maintains the level of a luminance signal before and after color tone correction.

5. A first video signal generated by a video signal processing device having an image quality adjusting means for an imaging means of the endoscope is output to a monitor means via a switching circuit, and
In an electronic endoscope apparatus for outputting a second video signal input from an external device to a monitor means via the switching circuit, a first video signal is forcibly output from the switching circuit, and an image quality adjusting means is provided. An electronic endoscope device, comprising: a reset switch for forcibly setting a predetermined value to a predetermined setting value.

6. In Supplementary Note 5, the image quality adjustment means has a color correction circuit for performing color adjustment and an outline emphasis circuit for performing outline emphasis. 7. In the supplementary note 5, the switching circuit forcibly outputs the first video signal from the switching circuit by operating a reset switch even when a plurality of external devices are connected, and sets the image quality adjusting means to a predetermined set value. To force it. 8. In Appendix 6, the color correction circuit prevents the luminance signal level from changing before and after color correction. 9. In Supplementary Note 5, the video signal processing device is connected to an external device by a communication unit, and releases the connection by the communication unit by operating the reset switch.

(Background of Supplementary Notes 5 to 9) As the current use state of the electronic endoscope apparatus, an external input image is input to the electronic endoscope apparatus, and both or one of the images is displayed on a monitor.
An endoscope image from an electronic endoscope device is input to an image file device, and its video output is projected on a monitor via the electronic endoscope device. In these conditions, troubles occur in devices other than the electronic endoscope device, and when the output video signal of those devices is disturbed, the image on the monitor is disturbed. When returning from such a state, the reset must be performed for each device, which is time-consuming and inconvenient. Often differ depending on the preference of other Dr. It was troublesome and troublesome to return to the standard value after use.

(Purpose of Supplementary Notes 5 to 9) When trouble occurs in devices connected to the electronic endoscope device, the devices can be reset from the electronic endoscope device. In addition, various setting values such as color tone can be returned to predetermined values.

[0127]

As described above, according to the present invention, a plurality of color signals are input, and the color level of the image displayed on the display means is corrected by adjusting the signal levels of the color signals. A first luminance signal level in the plurality of color signals before being input to the color correction means and a second luminance signal level in the corrected plurality of color signals output from the color correction means. A luminance signal comparing unit for comparing the luminance signal levels of the plurality of corrected color signals output from the color correcting unit based on a comparison result of the luminance signal comparing unit; Since the luminance signal correcting means for correcting the luminance signal level before the color correction by the correcting means is provided, even if the color correction is performed, the luminance signal level does not change before and after the color correction. It is color correction.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an image quality correction circuit according to a first embodiment of the present invention.

FIG. 2 is a block diagram illustrating a configuration of a luminance signal comparison circuit in FIG. 1;

FIG. 3 is a block diagram illustrating a configuration of an image quality correction circuit according to a second embodiment of the present invention.

FIG. 4 is a block diagram showing a configuration of an electronic endoscope apparatus provided with a third embodiment of the present invention.

FIG. 5 is an exemplary front view showing a video processor according to a third embodiment;

FIG. 6 is a block diagram showing a configuration of an electronic endoscope apparatus according to a first modification of the third embodiment.

FIG. 7 is a block diagram illustrating a configuration of an electronic endoscope apparatus according to a second modification of the third embodiment.

FIG. 8 is a block diagram showing a configuration of an electronic endoscope apparatus according to a third modification of the third embodiment.

FIG. 9 is a block diagram illustrating a configuration of an electronic endoscope apparatus according to a fourth embodiment of the present invention.

FIG. 10 is a diagram showing a specific configuration of a correction value setting circuit.

FIG. 11 is a block diagram illustrating a configuration of an electronic endoscope apparatus that outputs an image on the video processor side by a reset switch.

FIG. 12 is a view showing the entirety of a conventional electronic endoscope apparatus.

FIG. 13 is a diagram showing a configuration of an electronic endoscope and the like in FIG. 13;

14 is a diagram showing a color correction circuit based on a color difference signal in the image quality correction circuit of FIG.

FIG. 15 is a diagram illustrating a color correction circuit when color correction is performed using RGB signals.

FIG. 16 is a block diagram showing a conventional electronic endoscope apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 2 ... Electronic endoscope 7 ... Light source device 8 ... Video processor 10 ... Color monitor 41 ... Image quality correction circuit 42 ... Color difference / RGB conversion circuit 43 ... Color correction circuit 44 ... RGB / color difference conversion circuit 45 ... Luminance signal comparison circuit 46 ... Luminance signal correction circuit 47 ... Time adjustment circuit 48 ... Comparison circuit 49 ... Luminance signal correction value creation circuit

Claims (1)

[Claims] 1. A video signal processing apparatus having a color correction means for receiving a plurality of color signals and correcting a color state of an image displayed on a display means by adjusting signal levels of the color signals. A luminance signal comparison for comparing a first luminance signal level of the plurality of color signals before being input to the correction means with a second luminance signal level of the corrected plurality of color signals output from the color correction means. Means for correcting the luminance signal levels of the corrected plurality of color signals output from the color correction means based on the comparison result of the luminance signal comparison means, A video signal processing device, comprising: a luminance signal correction unit for performing correction.