JPH02286125A - Device for preventing color slippage - Google Patents

Abstract

PURPOSE:To securely obtain the still picture of small color slippage with simple configuration by storing the color slippage quantity of a picture signal until a result to judge whether the color slippage quantity is within a set value or not is obtained, canceling the storage when the color slippage quantity is more than the set value and executing the same operation to the picture signal after the cancel. CONSTITUTION:A doctor as a user determines a framing for a part, for which it is considered to obtain a freeze picture, and afterwards, a freeze/freeze cancel button 32 is pushed. Then, a freeze instruction signal FD is outputted. The picture of this part is once freeze and the color slippage quantity of the picture is detected. When it is judged that the color slippage quantity is small, freeze is held and when the color slippage quantity is large, the freeze is canceled unless a freeze cancel instruction is outputted (unless an instruction to stop the freeze is executed). The operation to detect the picture of the color slippage quantity less than a reference value is repeatedly executed again to the new picture and the freeze picture of the small color slippage quantity is held. Accordingly, the picture, for which the judging means of the color slippage quantity judges the small color slippage quantity, can be held as the freeze picture without fail.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a color shift prevention device that is provided with means for refreezing when a detected color shift δ exceeds a set value.

[Prior Art] In recent years, imaging means using solid-state imaging devices have come to be widely used in television cameras and endoscopes.

By using the above imaging means, it is easy to record, reproduce, or process images to be displayed on a monitor screen to make the features of interest more noticeable.

For example, when used in an endoscope or the like, an operation may be performed to freeze an image to make a still image in order to make a detailed diagnosis, and in this case, the image may freeze with a color shift.

For this reason, for example, in Japanese Patent Application Laid-Open No. 61-717191, the color shift in a still image is corrected, the color shift in the image is detected based on the difference between images taken at different times, and the amount of correction is calculated in nine images. This discloses a conventional example in which a person is warned, and the person who removes the image corrects the color shift based on the warning.

Furthermore, Japanese Patent Application Laid-open No. 167576/1983 discloses an image freezing device which does not freeze when there is a shift in the image, but freezes only when there is no shift in the image.

[Problems to be Solved by the Invention] In the above-mentioned Japanese Patent Application Laid-open No. 61-717191, the developer had to make corrections every time color shift occurred, which was inconvenient.

On the other hand, JP-A No. 60-26986 provides a frame memory for storing image signals for freezing, a control circuit for controlling this frame memory, and an operation panel equipped with switches for operating this control circuit. A freeze circuit was proposed.

Therefore, if an observer who observes the monitor wants to freeze the monitor and turns on the freeze switch on the operation panel, the image on the monitor will freeze even if there is a lot of deviation, and the observer will have to freeze again, which is a hassle. It is.

On the other hand, in the method of JP-A No. 63-167576, since the image is frozen after detecting the image shift, the actual frozen still image is different from the image determined to have no image shift, so it is not always necessary to Still images without image shift cannot be obtained.

The present invention has been made in view of the above-mentioned points, and it is an object of the present invention to provide a color shift prevention device that has a simple configuration and can reliably obtain still images with little image shift.

[Means and effects for solving the problem] In the present invention, the image signal is temporarily frozen in the image storage means based on the freeze instruction signal, and the frozen 1ih
l! & A re-freezing means that holds the frozen signal when the color shift level of the signal is within the set fa, unfreezes it when it exceeds the set value, and performs the same operation on the next frozen image signal. By providing this, it is possible to reliably display an image signal with little color shift as a still image.

[Example] Hereinafter, the present invention will be specifically described with reference to the drawings.

Figures 1 to 3 relate to the first embodiment of the present invention.
FIG. 2 is a block diagram showing the configuration of an endoscope apparatus equipped with the first embodiment, FIG. 2 is a block diagram showing the structure of the first embodiment, and FIG. 3 is an overall view of the endoscope apparatus.

As shown in FIG. 3, an endoscope apparatus 1 equipped with a first embodiment includes an electronic endoscope 2 equipped with an imaging means, and an electronic endoscope 2 equipped with an imaging means.
a video processor 5 incorporating a light source device 3 and a signal processing circuit 4 for supplying illumination light to the video processor 5; a color monitor 6 connected to the video processor 5 and serving as a display means;
The color misregistration prevention unit 7 of the first embodiment is connected to the JtA processor 5.

The electronic endoscope 2 has an elongated, for example, flexible insertion section 8, and a large-diameter operation section 9 is connected to the rear end of the insertion section 8. A flexible cable 11 extends from the operating section 9 to the side.
is extended, and a connector 12 is attached to the tip of this cable 11.
is provided.

The electronic endoscope 2 is connected to the video processor 5 via the connector 12.

On the distal end side of the insertion portion 8, there is a hard distal end portion 13 and a curved portion 14 that can be bent to the rear side and is in FA contact with the distal end portion 13.
are set up in sequence. Furthermore, by rotating a bending operation knob 15 provided on the operating section 9, the bending section 14 can be bent in the left-right direction or the up-down direction.

Further, the operating section 9 is provided with an insertion port 16 that communicates with a treatment instrument channel provided in the insertion section 8.

As shown in Figure 1, electronic endoscope #! A light guide 17 that transmits illumination light is inserted into the insertion portion 8 of L2. This light id 17 is connected to the cable 1 shown in FIG.
1 and connected to the video processor 5 , color-sequential illumination light is supplied from the light source device 3 to the end surface of the light guide 71 on the incident side.

Illumination light from a lamp 19 emitted by electric power supplied from a power source 18 passes through a rotary filter 22 that is rotationally driven by a motor 21, and red and green lights are attached in the circumferential direction of the rotary filter 22.

The light of each wavelength of red, green, and blue is sequentially passed through the blue color transmission filters 23R, 23G, and 23B, that is, the light is made into color-sequential light, and is irradiated onto the end face of the light guide 17 via the condenser lens 24.

The lamp 19 emits light in a wide range from ultraviolet to infrared, and can be a xenon lamp, a strobe lamp, or the like.

Note that the motor 21 is driven and controlled by a motor driver 25 so that its rotational speed is constant.

The illumination light transmitted by the light guide 17 is emitted forward from the end surface of the insertion section 8 on the distal end side. The object illuminated with this illumination light is imaged by the objective lens 27 attached to the distal end side of the insertion section 8 on the C0D 28 as a solid B pixel disposed at its focal plane.

This C0D 28 is sensitive to a wide wavelength range from ultraviolet to infrared regions, including the visible region, photoelectrically converts an optical image formed on this C0D 28, and accumulates it as a signal charge.

Thus, the driver 29 in the signal processing circuit 4 receives the signal I! The drive pulse transmitted through J30b causes C
The signal charge of 0D28 is read out and input to the preamplifier 31 in the signal processing circuit 4 via the signal Ia30a. For example, the operation unit 9 of the electronic scope 2 is provided with a freeze/unfreeze button 32 for issuing a freeze/unfreeze instruction.

The video signal amplified by the preamplifier 31 is input to a process circuit 33, where it undergoes signal processing such as r correction and white balance, and is converted into a digital signal by an A/D converter 34. There is. This digital video signal is processed by the select circuit 35.
For example, three R memories 36R, G memories 36G, B memories 36B1, . : It is designed to be stored selectively.

The signal data stored in the memories 36R, 36G, and 36B are simultaneously read out, converted into analog signals by the A/D converter 37, output as R, G, and B color signals, and input to the encoder 38. The signal is output from the encoder 38 as an NTSC combo signal.

Composite video A output from the encoder 38
The signal or RGB signal is input to a color monitor 6 to display the subject image in color. Note that, for example, a superimpose circuit (not shown) is provided before or after the D/A converter 37 to superimpose data such as patient data and date on the video signal.

The signal processing circuit 4 is provided with a timing generator 39 that generates the timing of the entire system.
0 is synchronized between each circuit, and a synchronization signal 5YNC of RGB signals can be outputted to the outside.

The memory controller 40 includes a memory 3 for R, G, and B.
Color signal data read/out for 6R, 36G, 36B
Controls writing.

This memory controller 0-40 also receives a freeze command signal @/freeze release command signal FC input via a terminal 41.
/FCC controls the freezing/unfreezing of the memories 36R136G and 36B.

Note that the freeze/freeze release button 32 is connected to the signal line 30.
It is connected to the terminal 42 via c.

Therefore, the color shift prevention unit 7 is added to the video processor 5.
By connecting the connector 43, the color misregistration prevention unit 7 receives, for example, two color signals G.

B, synchronization signal 5YNC, button 32 freeze instruction/
Freeze release command signals FD/FCD are input thereto, and freeze command/freeze release command signals FC/FCC can be output to the memory controller 40.

When a freeze instruction is given by the freeze/freeze release button 32, this color shift prevention unit 7 outputs a freeze command signal FC to the memory controller 40 at - time.
and two color signals G.

The amount of color shift is detected by calculating the correlation amount of B, and if the color shift amount is less than a set value, the memory controller 40 is caused to hold the freeze command signal FC. Also, if the detected amount of color shift is greater than the set value, the freeze release command signal FCC is output, and then the freeze command signal F is output again.
It has a function of temporarily outputting C and performing a similar operation (unless the freeze cancellation instruction signal FCD is input), and finally freezing the image in which the detected amount of color shift is equal to or less than the set value.

Next, the color misregistration prevention unit 7 will be explained with reference to FIG.

The synchronizing signal 5YNC is input to the timing generation circuit 51, which generates a mask pulse MP, a clamp pulse CP, and a reset pulse RP as a timing 41M required by each circuit.

Furthermore, among the color signals R, G, and B, the two color signals @G and B, which have a high correlation as an endoscopic image, are sent to buffer circuits 52a and 52a, respectively.
52b.

Each color signal outputted from the buffer circuits 52a and 52b is input to inverse γ correction circuits 53a and 53b that perform inverse γ correction, and after inverse γ correction is performed, the signals are input to mask circuits 54a and 54b, respectively. .

As shown in FIG. 3, each mask circuit 54a, 54b has a masking circuit for masking a data area 6Δ containing patient's name, other data, date, etc., so as not to pass the video signal portion of the endoscopic image 6B. A mask pulse MP is applied, and in synchronization with the mask pulse MP, video signal portions of the family celebration chain image &6B portion are cut out and input to the next stage AGC circuits 55a and 55b, respectively.

The AGC circuits 55a and 55b have two color signals G,
The signals with the same level are sent to clamp circuits 56a and 56b, respectively.
is input. In each clamp circuit 56a, 56b, the pedestal level of each signal is clamped by the clamp pulse CP generated by the timing pulse generation circuit 51, and the pedestal levels are made equal.

The output signals of the clamp circuits 56a and 56b are input to a subtraction circuit 57, a difference between the two signals is detected, and an absolute value circuit 58 at the next stage calculates the absolute value of the difference.

In a normal endoscopic image, the correlation between the G and B image components is high, so when the amount of color shift is small, the output value of the absolute value circuit 58 is small, whereas when the amount of color shift is large, the absolute value The output value of circuit 58 becomes smaller.

In other words, the output value of the absolute value circuit 58 becomes a color shift amount detection signal representing the color shift m between two corresponding pixels.

The output signal of the absolute value circuit 58 is input to a mask circuit 59, is cut by a mask pulse MP for removing noise other than the required image reliability, and is input to an integration circuit 60.

Under the control of the detection control circuit 61, this integrating circuit 60 performs an operation to integrate the color shift difference for one screen, obtain the color shift difference for one screen, and output it to the next-stage comparison circuit 62. .

A reset pulse RP from the timing generation circuit 51 is input to the detection control circuit 61, and by outputting this reset pulse RP to the integration circuit 60, the amount of color shift previously integrated by the integration circuit 60 is reset. Next 1
An operation is performed to integrate the color shift signal for the screen.

A comparison circuit 62 to which the output signal of the integration circuit 60 is input.
, a reference value voltage corresponding to the upper limit of color shift level for which freezing is permitted is inputted from the reference value setting circuit 63, and compared with the color shift level from the integrating circuit 60. Therefore, when the color shift amount from the integrating circuit 6o is within the reference value, that is, within the allowable color shift range, the comparison circuit 62 outputs a "HII level freeze permission signal; outputs a 141u level signal, a signal that releases the freeze.

The output of the comparison circuit 62 is input to a freeze and unfreeze circuit 63.

The freeze/freeze release circuit 63 is further connected to the freeze/freeze release button 3 via the signal processing circuit 4.
Freeze instruction/freeze release instruction signal FD/F from 2
A CD is input. This freeze & unfreeze circuit 6
3 outputs a -n freeze command signal FC to the memory controller 40 when the freeze command signal FD from the freeze/freeze release button 32 is input, and outputs a -n freeze command signal FC to the memory controller 40 for R and G.

B memories 36R, 36G, and 36B are set to the -H freeze state. In other words, writing is prohibited and updating with new image data is prohibited (stopped).

Next, a signal is sent to the detection III control circuit 61, and the integration circuit 6
0 is reset, and - the amount of color shift for the temporally frozen image signal is integrated for one screen. Therefore, the integration circuit 60 for this frozen image signal
The integrated signal of is compared with a reference value by the comparison circuit 62, and if the output of the comparison circuit 62 is at the 118" level, the freeze permission signal or the freeze command signal FC is continuously outputted from the freeze & unfreeze circuit 63, and - This comparison circuit 62 holds the temporally frozen image in a frozen state.
When the output is at the "L" level, the freeze & unfreeze circuit 63 outputs the unfreeze command signal FCC,
Memo, memory 36R, 36 via recontroller 40
G and 36B are brought into the freeze release state and the freeze command signal FC is outputted again.

In other words, new image data is written.

Note that when the freeze is released, the detection a, II control circuit 6
1 outputs the reset pulse RP to the integrating circuit 60 and performs the color shift detection operation for the next frozen image;
Stops the color shift detection operation. This freeze command signal F
When new image data for one frame is stored in the R, G, and B memories 36R, 36G, and 36B by C,
-H
Set to frozen state.

As mentioned above, the amount of color shift is detected for this frozen image, and if it is below the reference value, the frozen image is kept frozen, and if it is above the reference value, it is unfrozen and a new one is created. The image is taken in and the same operation is repeated J0. Therefore, after some time has elapsed after the freeze instruction is issued, a frozen image with less color shift m can be obtained.

To convert a frozen image into a moving image, press the freeze/freeze release button 32 and output the freeze release instruction signal FCD. Unfreeze the memories 36R, 36G, and 36B and set them to video mode.

According to this first embodiment, after the doctor as the user determines the 7-raming of the area where he/she thinks the frozen image has been obtained,
When the freeze/unfreeze button 32 is pressed to output the freeze instruction signal FD, the image of that area is frozen for one frame, the amount of color shift in that image is detected, and if the amount of color shift is determined to be small, will keep the freeze, and if the color shift is large, it will be unfrozen unless an instruction to cancel the freeze is output (unless an instruction to cancel the freeze is issued), and the color shift will be less than the standard value for the new image again. By repeating the operation of detecting the intervening images, a frozen image with a small amount of color shift is retained.

Therefore, according to the first practical example, an image that is determined to have little color shift by the color shift determining means can be reliably held as a frozen image.

Further, according to the first embodiment, a still image (freeze image) with a small amount of color shift can be iqed with a simple circuit configuration without providing a new memory means. Furthermore, this frozen image with less color shift can be obtained by a single freeze instruction operation.

Therefore, it is possible to improve the operability of a frame-sequential endoscope, and it is also possible to contribute to improving diagnostic performance by providing a still image with a small amount of color shift.

FIG. 4 shows a color shift prevention unit 71 according to a second embodiment of the present invention.
shows.

This second embodiment differs from the first embodiment shown in FIG. 2 in that the output signals of the clamp circuits 56a and 56b are input to a division circuit 72, and the ratio between the two color signals G and B is calculated. In the calculated ratio, if the denominator is the noise level, that is, the black level in the original image or something close to this, it will cause an error in the calculation result, so in order to remove the influence of the noise level etc. , controls the level of the calculated video signal ratio and sends it to the mask circuit 59.

The output of this mask circuit 59 is input to an integration circuit 60, and the output 1 of this integration circuit 60 is input to a comparison circuit 62. The output of the comparator circuit 62 is input to the freeze release circuit 63 and also to the timer circuit 74. When the output of the comparator circuit 62 is at the "L''" level, the timer circuit 74 delays the signal output from the freeze/freeze release circuit 63 and outputs the delayed signal to the freeze/freeze release circuit 63. When the output signal of the output signal is "[1" level], the delay operation is stopped.

In other words, when the color shift is large, the timer circuit 74 causes moving images and still images to be displayed temporarily at regular intervals. Then, in the case of this still image, it is determined whether the color shift amount is below the reference value or not. If it is above the reference value, the moving image and still image are continued to be displayed, and the color shift amount J that is below the reference value is determined. In this case, the delay operation of the timer circuit 74 is stopped, and the freeze command signal FCC is output from the freeze release circuit 63 to maintain the frozen state.

The general operation of this second embodiment is as shown in FIG.

As shown in FIG. 5(a), when the freeze instruction signal FD is output by operating the freeze/freeze release button 32,
The freeze release circuit 63 uses a reset pulse RP.
At the same time, it outputs a freeze command signal FC of "IIH" (not shown in the figure (b)).This signal FC causes the memory 3
6R, 36G, and 36B are in still image mode as shown in FIG. 6(d). This still image mode period lasts at least for a period 111 during which color shift detection is performed on this still image and the determination result is determined.

The freeze command signal FC is input to the timer circuit 74, and when the comparator circuit 62 determines that the color shift is large (the level is ``L'' in FIG. 5(e)), the timer circuit 74 is input to the timer circuit 74. As shown in (C), this freeze command signal FC is delayed for a certain period of time T and outputted to the freeze-freeze release circuit 63. Therefore, the freeze-freeze release circuit 63 outputs the freeze command signal FC at fixed time intervals T. Output.

A period in which the freeze command signal FC is not output is a freeze cancellation period, and the memories 36R, 36G, and 36B are in the moving image mode.

In this way, the still image and moving image modes are repeated at fixed time intervals T.

Therefore, in each still image mode, if the color shift J+1 for the still image is detected and the comparison circuit 62 determines that the color shift it is less than the reference value, the output is "
HD level, and this "H'" level stops the delay operation of the timer circuit 74, and causes the freeze command signal FC to be continuously output from the freeze cancel circuit 63 as shown in section 5(b), and the memory 361, 36
G, 3613 retains the freeze mode.

Note that when a freeze cancellation instruction is issued, the freeze mode is canceled and the mode returns to the normal video mode.

This second embodiment has the same effect as the first embodiment, and detects the amount of color shift by using, for example, the ratio of G and B image signals. It is possible to prevent the color misregistration detection level from fluctuating due to the color misregistration m, thereby improving the color misregistration detection ability.

Note that in each of the above embodiments, the memories 36R and 36G.

Although the amount of color shift is detected for the signal read out from the memory 36B, the present invention is not limited to this.
Color misalignment may also be detected directly.

Further, in order to detect color misregistration, a memory means may be provided, and the color misregistration may be detected by detecting the level difference between the same colors one field or one frame before. Further, a memory means may be provided and the amount of color shift may be detected by detecting a level difference between different colors.

Furthermore, when detecting color shift transmission, portions where the image signal is saturated may not be used for color shift detection. Further, the color shift m detection may be standardized using an image signal portion (between m) in which the color shift amount is not detected or an image signal portion in which the color shift M is detected.

In addition, if a memory means is provided to detect the amount of color shift, it may be possible to detect the color shift ω within one field/frame period, and in this case, when a freeze instruction is given, the color shift amount If the value is greater than the reference value, it is possible to make the image almost the same as the video.

Incidentally, the present invention can also be applied to an apparatus using an external television camera, in which a television camera equipped with a built-in COD or the like is attached to the eyepiece of a fiberscope.

Effects of the Invention] As described above, according to the present invention, the freeze instruction means determines whether or not the color shift extent of the image signal stored in the image storage means is within a set value. If the value exceeds the set value, the memory is canceled and the same operation is performed on the image signal after the release, and the image signal with color shift within the set value is converted into a still image. Since the image signal is stored in the storage means, the image signal with the least color shift can be reliably stored as a still image.

[Brief explanation of the drawing]

Figures 1 to 3 relate to the first embodiment of the present invention.
The figure is a block diagram showing the configuration of an endoscope apparatus equipped with the first embodiment, FIG. 2 is a first block diagram showing the configuration of the first embodiment, FIG. is a block diagram showing the configuration of a second embodiment of the present invention, and FIG. 5 is an explanatory diagram of the operation of the second embodiment. 1... Endoscope device 2... Electronic endoscope 3...
-Light source device 4...Signal processing circuit 5...Video processor 6...Color monitor 7...Color shift prevention unit 32...Freeze/freeze release button 36R, 36
G, 36B...Memory 40...Memory controller 60...Integrator circuit 61...Detection control circuit 6
2... Comparison circuit 63... Reference value setting circuit 6
4... Freeze & Unfreeze Circuit Figure 7 Color rII'IT): fkl Knee y 'r Figure 4 Procedure Neyama, tEρR (spontaneous) 1. Display of the case 1999 Patent Application No. 108046 2, Name of the invention Color shift prevention device 3, Person making the amendment Relationship with the case

Claims (1)

[Scope of Claims] An endoscopic imaging device comprising an imaging means for imaging a subject sequentially illuminated with illumination light in different wavelength ranges, and an image storage means for temporarily storing the imaged image signal. freeze command means for outputting a freeze command signal to temporarily freeze an image to the image storage means in response to an instruction signal; color shift detection means for detecting the amount of color shift with respect to the frozen still image; a determining means for determining whether the amount of color misregistration detected by the detecting means is within a set value; and when the determining means determines that it is within the set value, the freeze command signal is held, and it is determined that the amount is equal to or greater than the set value. 2. A color misregistration prevention device, further comprising refreeze control means for once canceling said freeze command signal and freezing a new image in said image storage means.