JPH0241131A - Electronic endoscope apparatus - Google Patents

Abstract

PURPOSE:To automatically prevent the standstill or hard copy of a color shift image when a monitor image is allowed to stand still or converted to hard copy by judging whether an image is an animation or a stationary image on the basis of the color image of one field or one frame before conversion according to a simultaneous system and the color image of one field or one frame succeeding thereto. CONSTITUTION:An imaging lens 22 picks up the image of an object 18 illuminated by respective illumination lights of red, green and blue to form said image on the light detection part of a CCD sensor 24 and the formed image is outputted to an A/D converter 28 and a freeze control circuit 50. The freeze control circuit 50 judges whether the taken image is an animation or a stationary image on the basis of an inputted color image signal and prevents the output of the freeze order signal inputted during a period judging the taken image as the animation and outputs only the freeze order signal inputted during a period judging said image as the stationary image as a freeze control signal. By this method, the color image signals of the same image are respectively outputted from field memories 32, 34, 36 during a preset freeze period without renewing memory contents to allow a monitor image to stand still.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electronic endoscope device, and particularly to a medical electronic endoscope device that captures images in a frame-sequential manner.

[Conventional technology]

The field sequential method, which sequentially obtains color images corresponding to each color of illumination light from one CCD two-dimensional sensor, is effective when a large number of CCD two-dimensional sensors cannot be used, and has recently been applied to medical electronic endoscope devices. .

Such an electronic endoscope device is configured to convert color images (elements) sequentially captured in response to illumination light into red, green, and blue field memories simultaneously, and to reproduce them as color images on a color TV. In addition, when a freeze command is applied to freeze the monitor image, the stored images in the red, green, and blue field memories are latched so that the still image can be monitored. Once connected and a hard copy command is added, the still image can be hard copied.

[Problem that the invention seeks to solve]

By the way, in the field sequential method, the color image of each color channel is l
This occurs with a frame-by-frame delay, and this is converted into a simultaneous system and reproduced as a color image. Therefore, in conventional electronic endoscope devices, when the monitor image is frozen by the freeze command, the subject and the endoscope are Movement between the tips could cause color shift in a stationary monitor image.

In addition, if a hard copy command is added to make a hard copy of a monitor image, the color shift described above will lead to waste of copy paper, while if only good still images are hard copied, the still monitor image will be There is a problem that the hard copy command must be added after visually confirming the quality, which is complicated.

The present invention has been made in view of the above circumstances, and can automatically prevent a color-shifted image from being frozen or hard-copied when a monitor image is frozen or hard-copied using a freeze command or a hard-copy command. The purpose is to provide an electronic endoscope device.

[Means for solving problems]

In order to achieve the above object, the present invention provides an electronic endoscope apparatus that sequentially captures desired color images in a frame-sequential manner, converts the color images simultaneously, and reproduces them as color images. 1 field or 1 before converting to simultaneous
determining means for determining whether or not it is a moving image based on the color image of the frame and the color image of one subsequent field or one frame; and keeping the input monitor image still during the period when the determining means determines that it is a moving image. The present invention is characterized by comprising a blocking means for blocking output of a freeze command or a hard copy command for making a hard copy of a monitor image.

[Effect]

According to the present invention, in an electronic endoscope device that captures images in a frame-sequential manner, one field or one frame of color image before each color image is converted into a simultaneous system, and one subsequent field or one
By comparing the color images of the frame, it is determined whether or not it is a moving image. During the period when it is determined to be a moving image, even if a freeze command to freeze the monitor image or a hard copy command to hard copy the monitor image (tl) is input, the output is blocked, thereby freezing the color-shifted image. I try not to let anyone else use it or make a hard copy of it.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an electronic endoscope apparatus according to the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a block diagram showing an embodiment of an electronic endoscope device according to the present invention. This electronic endoscope device sequentially captures desired color images in a frame-sequential manner, converts the color images simultaneously, and reproduces them as a color image, and the light from the illumination lamp 10 is removed from near-infrared A subject 18 is illuminated from the tip of the endoscope via a filter 12, a color filter disk 14, and a light guide 16. That is, the color filter disk 14 has a red filter, a green filter, and a blue filter, each having a central angle of 120 degrees, and is rotated by a motor 20 at a predetermined rotational speed (for example, 2 [1 rps). As a result, the light from the illumination lamp 10 becomes red, green, and blue illumination light that sequentially changes at a cycle of 1/60 seconds via the rotating color filter disk 14.
It is applied to the subject 18 via the light guide 16.

The imaging lens 22 provided at the tip of the endoscope has red, green,
Image the subject 18 illuminated by each blue illumination light,
This is imaged on the light receiving part of the CCD sensor 24, and the CCD sensor 24 photoelectrically converts the incident light and sends the color image signal corresponding to each illumination light to the A/D converter 28 via the amplifier 26.
and output to the freeze control circuit 50.

The A/D converter 28 is connected to the synchronous port i! A predetermined color lock pulse is applied from 830, and thereby the input color image signal is converted into a digital signal pixel by pixel, and this digital signal is sent to the red, green, and blue field memories 32.3, respectively.
Output on 4.36. Field memory 32.34.3
6 is driven and controlled by a memory control circuit 38. That is, the memory control circuit 38 receives signals synchronized with each of the red, green, and blue illumination lights from the synchronization circuit 30, and stores color image signals corresponding to each illumination light in the field memory corresponding to the color. Each field memory 32, 34 .
A write signal is sequentially output to 36 to update the contents stored in the feed memory. These field memories 32.3
The color image signals stored in 4.36 are simultaneously read out,
They are output via D/A converters 40, 42, and 44, respectively.

Then, red, green, converted to simultaneous expression as above,
The blue color image signal is converted into an NTSC video signal via a color encoder (not shown), etc., and is added to a color TV and reproduced as a color image.

On the other hand, to the freeze control circuit 50, as described above, the color image signals before being converted to the simultaneous type are sequentially applied, and a freeze command signal for freezing the monitor image can be input. .

The freeze control circuit 50 determines whether the captured image is a moving image or a still image based on the input color image signal, and prevents the output of the input freeze command signal during the period when the captured image is determined to be a moving image. Only the freeze command signal input during the period being determined is output as a freeze control signal (H level signal). Freeze system H wholesale (No. 8 is added to each field memory 32, 34, 36, and when the signal becomes H level, each field memory 32, 34,
Latch 36. As a result, each field memory 32, 34, 36 does not update the stored contents for a preset freeze period (several seconds), outputs color image signals of the same screen, and freezes the monitor image.

Next, the freeze control circuit 50 will be explained in detail with reference to FIGS. 2 and 3.

FIG. 2 is a block diagram showing one embodiment of the freeze control circuit 50. This freeze control circuit 50 includes a contour signal generation circuit 51. It is composed of a comparison circuit 52, a memory 53, a memory control circuit 54, a moving image control circuit 55, and an AND circuit 56.

A color image signal (FIG. 3(B)) is applied to the contour signal generating circuit 51 from an input terminal B. This color image signal is a green (G), red (R), and blue (B) color image signal that is input in a frame sequential manner, and has a waveform synchronized with the period of the VD pulse (Fig. 3 (A)). have. Furthermore, in Figure 3 (A),
0 indicates an odd field and E indicates an even field.

Further, to the contour signal generating circuit 51, a gate pulse is applied from the input terminal C for selectively processing only the G color image signal of the odd field (FIG. 3(C)).

This contour signal generation circuit 51 receives only the G color image signal of the odd field selected by the gate pulse among the frame sequential color image signals, and receives the contour portion of the image (position where the contrast suddenly changes) indicated by the color image signal. is detected and outputs a contour signal (pulse signal) to the comparison circuit 54 and memory 53. Incidentally, FIG. 3(D)) shows an example of the contour signal (signal on line D) generated by the contour signal generation circuit 51.

The memory 53 temporarily stores the contour signal and outputs it to the comparison circuit 52 after a certain period of time has elapsed.The output period of the odd field G color image signal is controlled by a signal applied from the memory control circuit 54 via the line M. The memory clock pulse applied via line N allows writing and reading of contour signals. Incidentally, FIG. 3(E) shows the contour signal (signal of line E) read out from the memory 53.

As is clear from FIGS. 3 (D> and (E)), the memory 53 stores the stored contour signal after 6 fields of time (0
, 1mS later), the input signal is Q, 1m
s acts as a delay means.

Comparison circuit 52 is enabled by a signal applied via line M and compares the two input signals. Then, as shown in Figure 3 (F), when the two input signals do not match (2
The output signal (line F signal) changes from L level to H level, is reset in synchronization with the next VD pulse, and becomes L level again.

The moving image discrimination circuit 55 outputs an L-level freeze prevention signal when the captured image is a moving image, and the comparing circuit 5
At the same time, a gate pulse similar to the gate pulse applied to the contour signal generating circuit 51 is applied from the input terminal 0. The video discrimination circuit 55 is triggered by the fall of the H level signal applied from the comparator circuit 52 and becomes an L level, and the freeze prevention signal is maintained at the L level until the next odd field G color image signal reaches Hiiragi. (FIG. 3(G)) is output to the AND circuit 56 via line G. Note that, while the freeze prevention signal is being output, if the next comparison output (signal that changes from H level to L level) is applied from the comparison circuit 52, it will be retriggered.

The AND circuit 56 is configured to receive the output signal of the moving image discrimination circuit 55 as well as a freeze command signal from the input terminal P. During the input period of the freeze prevention signal, it becomes inoperable, and the freeze command signal (
Even if a high level (H level) is input, its output is blocked. That is, as shown in FIG. 3(H), at time 1. When the freeze command signal is input at , the AND condition is not satisfied due to the freeze prevention signal, and then, when the freeze prevention signal becomes H level at time t2, the AND condition is satisfied, and the AND circuit 56
A freeze control signal (H level signal) shown in FIG. 3(I) is outputted from. Furthermore, when the freeze command signal is input at time t as shown in FIG. 3(J), the AND condition is immediately established, and the AND circuit 56 outputs the
A freeze control signal shown in K) is output.

In the above embodiment, even if the AND condition is not satisfied by the freeze prevention signal when the freeze command signal is input, if the AND condition is satisfied thereafter, the freeze split cylinder signal is output at that point. However, it may be determined whether the AND condition is satisfied only when the freeze command signal rises, and when the AND condition is not satisfied, the freeze control signal may not be output even if the AND condition is satisfied thereafter.

As shown in FIG. 1, since each field memory is latched by the freeze control signal, a still image without color shift can always be reproduced.

Also, this control signal connects the electronic endoscope device.
may be configured to operate a hard copy device that is
In this case, it is possible to always make a hard copy of an image without color shift.

Incidentally, in this embodiment, out of color images input sequentially, images of the same color are compared with each other, but images of different colors may be compared with each other. Further, the means for determining whether it is a moving image or a still image is not limited to this embodiment, and may be based on the coincidence or mismatch between two color images, such as a method of determining based on a cross-correlation between a preceding color image and a subsequent color image. Any method may be used as long as it can be determined based on the

〔Effect of the invention〕

As explained above, according to the electronic endoscope device according to the present invention, it is determined whether or not there is a moving image based on the coincidence or mismatch between the preceding color image and the subsequent color image before simultaneous conversion, In the case of a moving image, since a freeze command and a hard copy command are not output, when a monitor image is stilled or hard copied, it is possible to automatically prevent a color-shifted image from being stilled or hard copied.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an embodiment of an electronic endoscope device according to the present invention, FIG. 2 is a block diagram showing details of the freeze control circuit in FIG. 1, and FIGS. 3 (A) to (K) are timing charts used to explain FIG. 2, respectively. 32.34.36...Field memory, 50.
... Freeze control circuit, 51 ... Contour signal generation circuit, 52 ... Comparison circuit, 53 ... Memory, 55.
...Video discrimination circuit, 56...AND circuit.

Claims (2)

[Claims] (1) In an electronic endoscope device that sequentially captures desired color images in a frame-sequential method, converts the color images into a simultaneous method, and reproduces them as a color image, the first step before converting to the simultaneous method. Discrimination means for discriminating whether or not it is a moving image based on a color image of one field or one frame and a color image of one subsequent field or one frame; and a monitor image to be input during a period when the discriminating means discriminates it as a moving image. An electronic endoscope device comprising: blocking means for blocking output of a freeze command to freeze the monitor image or a hard copy command to hard copy a monitor image. (2) The discrimination means includes a contour signal generation circuit which inputs one field or one frame of a color image before being converted into the simultaneous type, detects a position where the contrast of the color image suddenly changes, and outputs a pulse signal. , a delay means for delaying and outputting a pulse signal output from the contour signal generation circuit by a predetermined number of fields or a predetermined number of frames; and an output signal of the contour signal generation circuit and an output delayed by the delay means. 2. The electronic endoscope apparatus according to claim 1, further comprising comparison means for comparing the signals and determining that the signals are moving images when they do not match.