JPH11339006A - Image capturing device - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To realize a capturing device capable of capturing an image of an affected part or the like as a high-quality digital image with an external trigger using an endoscope camera. An image capturing device converts an image output signal of a video camera 1 such as an endoscope by an A / D converter 4 and inputs it as a digital image signal to a computer. External trigger means 5 for instructing timing, and a frame memory 7 for periodically updating and storing digital data of N frames (frames) of time-series image data being monitored.
Means for controlling an update to be taken into the frame memory 7 at the time when an external trigger operation is performed, and selecting or processing an appropriate image from images buffered before and after the trigger time. Is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image capturing apparatus for inputting an image signal of a video camera operated by an operator as a digital image signal (still image), and more particularly to a digital image signal for only an image designated by the operator. The present invention relates to an image capturing device that captures and stores the captured image.

[0002]

2. Description of the Related Art Generally, an image capturing apparatus displays an analog output image of an endoscope camera or the like used for inspection of a digestive organ of a human body or an industrial plumbing on a monitor television or the like, and designates the image by an operator. It captures and stores only image data necessary for examination records and case studies as digital images.

A document describing this image capturing device is disclosed, for example, in Japanese Patent Application Laid-Open No. 7-250304, and a still image recording device described in this document is capable of transferring an image from a medical endoscope or the like to a foot switch or the like. , A still image is captured at intervals of about one second by the trigger signal, and continuous images are captured and recorded.

According to the prior art disclosed in the above publication, when a video image output signal for an endoscopy or the like is A / D converted and captured and recorded as a digital image signal, an operator can capture the image by using a foot switch, a keyboard or an external device. , And an image of one frame (one screen) constituting unit is continuously captured at intervals of about 1 second from that point in time, and the image of one frame unit is recorded as a still image.

[0005]

The image capturing apparatus according to the prior art described above has a possibility that the captured image may capture a delayed image with respect to a required image due to a delay in the operation of the operator, and a camera operation blur of the operator. No consideration has been given to the effect of blurring of the image caused by the above, and there is a problem that it is difficult for the operator to capture the required image.

When the output signal from the video camera is an interlaced output, the position shift between the odd field image and the even field image is large, and it is possible to select and record a one-frame image synthesized with improper capture timing. There was a defect that there is.

[0007] Further, in the conventional apparatus, the captured image is directly subjected to A / D conversion and filing.
There is also a problem that noise of a video camera image signal is taken as it is as a still image, and noise that is inconspicuous as an analog video image becomes noticeable by digital conversion.

More specifically, an image capturing device for an endoscope captures a video camera image output signal with good timing in order to record an abnormal portion or the like of an inspection image within a predetermined range by manual operation of an operator. However, in order to efficiently capture only the necessary images from the time-series image data that is being monitored while moving to search for an abnormal part, the above-mentioned operation timing delays and blurring have led to mastering. Had to be required.

In other words, the problem to be solved by the present invention is to output an image from a video camera such as an endoscope (here, NTS).
C system: Refers to the National Television System Committee system, etc.) In an image input device that A / D converts a signal and inputs it to a computer as a digital image signal, an operator can easily monitor a monitor image and obtain a desired image with high quality. It is an improved and easy-to-use image capturing device that enables capture.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the above-mentioned disadvantages caused by the prior art. Regardless of the skill of the operator, it is possible to prevent a timing failure image from being captured due to a slight operation delay of the operator, and to make noise which is not noticeable in a moving image. It is an object of the present invention to provide an image capturing device which can reduce the image quality and easily capture a more appropriate image.

[0011]

In order to achieve the above object, an image capturing apparatus according to the present invention comprises a monitor for displaying an image signal of the video camera, and an external trigger means for instructing a timing of capturing the image signal. A frame memory for storing a digital image signal of N frames or more obtained by converting the image signal of the video camera into a digital signal, and when the timing of taking in the image signal is instructed by the external trigger means, By updating the capture to the frame memory by the number of frames specified in advance and then stopping,
A first feature is that an arbitrary image can be selected from a plurality of pieces of digital image data before and after the trigger based on a timing at which a timing instruction is issued by the external trigger means stored in the frame memory.

Further, according to the present invention, in the image capturing apparatus according to the first aspect, a designating means for designating a writing cycle to the frame memory is provided, and a timing for taking in an image signal is designated by the external trigger means. When a timing instruction is given by the external trigger means, an arbitrary image can be selected from a plurality of digital image data stored in a frame memory in accordance with the writing cycle before and after the trigger. In the apparatus according to the first and second aspects, when an arbitrary image is selected from the plurality of digital image data stored in the frame memory, the number of frames due to a predetermined operation delay of the external trigger means is selected. External trigger means that is expected in advance by providing means for automatically selecting an image Compensating for an operation delay is a third feature. Similarly, in the devices of the first and second features, when selecting an arbitrary image from a plurality of digital image data stored in a frame memory, A fourth feature is that by selecting an image obtained by averaging images of an arbitrary number of frames, noise in a still image is reduced and high-quality output is enabled.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an image capturing apparatus according to an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a system configuration diagram showing an image capturing apparatus according to the present embodiment, FIG. 2 is an operation flowchart showing an image capturing operation, and FIG. 3 is a magneto-optical disk including a noise reduction processing flow of a captured image. 9 is a flowchart illustrating an example of a filing operation.

The image capturing device shown in FIG.
A video camera 1 connected to an endoscope or the like; a monitor input switching circuit 2 for selectively outputting an image output of the video camera 1 or an output signal of a D / A converter 9 described later as an input; A video monitor 3 for displaying a moving image or a still image based on an output signal from the circuit 2 and an image output from the video camera 1 are converted into digital signals (8 bits / Pi for each of R, G, B in a normal color image system configuration).
xel) and a trigger switch 5 for specifying a still image to be captured by an operator's operation
And a controller 6 connected to the trigger switch 5 and the A / D converter 4 for controlling, and N or more frames obtained by converting an image signal from the video camera 1 into a digital signal (in FIG. 1, FM 7-1 to FM 7-1). A frame memory 7 for storing digital image signals (three frames of FM 7-3), a frame switching circuit (MPX) 8 for switching an output signal from the frame memory 7, and a digital image output from the frame switching circuit 8. D is converted into an analog signal and supplied to the monitor input switching circuit 2.
/ A converter 9, CPU (computer) 100, BUSA (bus adapter) 10 connected to controller 6 and frame switching circuit 8 via bus 120
1, HDD (magnetic disk device) 102, MM (main memory) 103, MOD (magneto-optical disk device) 104
And so on. Note that the output of the camera 1 and the A / D
A well-known band-limiting low-pass filter is generally inserted between the converter 4 and a noise suppressor. However, the description is omitted because it has no essential relation in describing the embodiment of the present invention.

An image output from the video camera 1 is displayed on a video monitor 3 via a monitor input switching circuit (hereinafter referred to as a monitor SW) 2 and converted into a digital signal by an A / D converter 4. Are sequentially stored in the frame memory 7. The frame memory 7 is composed of three frame memories FM1 to FM3, each composed of a well-known high-speed IC memory capable of independently performing a write operation and a read operation, and output from the video camera 1 as described later. A frame memory function of temporarily storing a time-series image in a frame image capture cycle controlled by the controller 6, and the read-out image signal is converted into an analog signal by a D / A converter 9 via a frame switching circuit 8. It is converted into a signal and can be monitored on the video monitor 3 via the monitor SW2.

The output of the frame switching circuit (MPX) 8 is connected to the system bus 120 of the CPU 100, and is sent to the MM 103 as image data via the BUSA 101 and the local bus 110 under the control of a control program (not shown). Can be stored.

The image data stored in the MM 103 is transmitted to the local bus 110, the system bus 120, and the BUS under the control of a control program (not shown).
It can be stored in the recording medium of the HDD 102 or the MOD 104 via A101. The system bus 120
A known interface control circuit is inserted between the HDD and the HDD 102 or the MOD 104. However, the interface control circuit has no essential relation in the description of the embodiment of the present invention, and a description thereof will be omitted.

Next, the operation of capturing an image signal from the video camera 1 will be described with reference to FIG.

When the image capturing apparatus according to the present embodiment starts capturing under the control of a control program (not shown) (step 200), the image signal from the video camera 1 is first converted to a digital signal and then to the FM1. It is stored as one frame image (for one frame) (step 201). Here, it is known that an image signal from the video camera can be captured (written) as a single frame image in a frame memory based on a vertical synchronization signal and a horizontal synchronization signal from the camera. When the storage in the FM1 is completed, the present apparatus monitors the ON / OFF state of the trigger switch, which is a signal for capturing an image from the operator (steps 202/204, 206). One frame image of the frame is sequentially stored in the corresponding frame memory FM (steps 203 to 20).
6).

If the trigger switch is detected to be ON in steps 202/204/206, the next one frame image is stored and updated in FM (step 207),
Stop memory update operation of M1 to FM3 (memory freeze,
Step 208), and the state shifts to a state where the operator can select any stored image (step 209). In other words, the previous and next frame images are stored based on the operation time of the trigger switch, and the state shifts to a selectable state. These operations are similarly performed in an arbitrary frame memory FMi (i
= 1 to 3), every time the trigger switch is turned ON / OFF, the ON / OFF state of the trigger switch is detected, and if ON, the next frame of FMi is set to 1 (if i is 3, the next is 1).
When the frame image storage is completed, the storage update operation of FM1 to FM3 is stopped (memory freeze). If the trigger switch is turned off by detecting ON / OFF, the storage of the next frame image is updated, and the time series operation is sequentially continued. After the image is captured in step 209, the capturing is terminated (step 211) or continued (returned to step 200) depending on whether or not the capturing can be continued (step 210).

As described above, in the image capturing apparatus according to the present embodiment, the trigger switches are turned on in the frame memories FM1 to FM3, as is apparent from the above description of the operation.
The image frames before and after the trigger are stored because the image frames before and after the trigger are stored even if the operator turns the trigger switch ON by one frame by storing the image frames before and after the time when the image is detected. You can select a frame.

In this embodiment, three frame memories are used.
Although the present invention has been described by way of example, the present invention is not limited to this, and more frame memories are prepared, and when the trigger is turned on, a larger number of preceding and succeeding frames are stored in an arbitrary number of preceding and succeeding frames. You can also. In this case, the selection range of the image frame can be further expanded. In particular, the frame image (one frame) output from the video camera is N
In the case of the TSC system, since it is an interlaced scanning signal as is well known, and is composed of an odd-field signal and an even-field signal, if the motion of the image is fast due to blurring of a video camera or the like at the time of imaging, the odd-field and even-field signals are used. Although the transition of the field is not smooth and the image is often disturbed, the storage and selection of the large number of image frames makes it possible to capture a more appropriate image.

In the above-described embodiment, an example in which a dedicated memory is used as a frame memory has been described. However, the present invention is not limited to this. It may be used as a large-capacity frame memory.

Further, in the above-described embodiment, an example has been described in which the reading cycle of the frame memory is fixed, for example, the number of frames per second in the NTSC system is 30 frames. However, the present invention is not limited to this and relates to the present invention. For capturing images, to capture and file a part of the slow moving image associated with the imaging operation as a still image,
It is not necessary to capture at 1/30 second intervals, and a means for controlling the capture interval is provided, for example, from 1/15 second (every two frames) to
A configuration may be adopted in which a required image is selected from frame images sampled and captured for 1/5 second (every 6 frames).

This sampling capture period can be easily set by the controller 6 shown in FIG. In addition, an inexperienced operator always has a time delay for operating the trigger switch after visually checking the monitor image, and the image to be captured is an image before the operation of the trigger switch. It is also possible to use a configuration in which an image that is a specified time or a specified number of frames before the ON time is buffered, and a means for automatically selecting from the plurality of images is incorporated. In this case, the time or the number of frames corresponding to the operation delay until the trigger switch is turned on by a normal operator is set in advance, and a candidate still image is displayed on a video monitor according to this setting, so that the operator can select the image. May be.

Next, an image capturing apparatus according to another embodiment of the present invention will be described with reference to the drawings. The hardware configuration itself of the image capturing device according to the present embodiment is the same as that shown in FIG. 1, and thus description thereof will be omitted, and the operation thereof will be described with reference to FIG.

First, the image capturing apparatus according to the above-described embodiment is configured to sequentially store a plurality of images from the video camera 1 in a frame memory so that the image can be selected by an operator. In order to perform the filing by the / D conversion, the noise of the video camera image signal may be taken as a still image as it is, and the noise that is not conspicuous as an analog video image may be conspicuous by the digital conversion.

Therefore, in the present embodiment, the processing shown in FIG. 3 is executed instead of the step 209 for selecting the captured image shown in FIG. In this process, following the program start (step 300), initial conditions (the number of added frames in the noise reduction process described later, weighting of averaging, etc.)
Is set, and whether or not to apply the noise reduction processing after the capturing (step 302) (step 30)
If the operator confirms 3) and performs noise reduction processing, image data for a plurality of (N) frames is accumulated (step 304), and pixels of the plurality of image data are added and averaged (noise reduction processing). Then, pixel averaging calculation processing is performed (step 305), the image of the averaged frame is displayed (step 306), and writing to the magneto-optical disk is performed (step 307).

A step may be added between steps 306 and 307 to allow the operator to select whether or not the data can be stored on the magneto-optical disk. If it is instructed not to perform the noise reduction processing in step 303, the image of the frame is displayed as it is in step 306, and the processing is continued. In this embodiment, the example in which the image is stored on the magneto-optical disk has been described. However, the present invention is not limited to this, and the image may be stored in the main memory or other recording means.

As described above, the image capturing apparatus according to the embodiment includes an external trigger means for instructing a timing at which an operator captures an image output from a video camera such as an endoscope while viewing a monitor image, And a frame memory for periodically updating and storing N frames (frames) of digital image data of the image data, and when the external trigger operation is performed, the time-series image data is stored in the frame memory. A means for stopping (freezing) the capture update and selecting an appropriate image from among the images stored in the frame memory and among the images buffered before and after the trigger point is provided. Can be easily selected. According to each embodiment, the capturing timing is solved by selecting a time-series image in the memory, and the image quality is selected from among images in the memory, an image determined by the operator to be good, or a frame image. High image quality can be achieved by image processing for reducing noise by pixel averaging processing, filtering processing, and the like.

Note that the present invention can be represented as the following embodiments.

<Embodiment 1> In an image capturing apparatus for A / D converting an image output signal of a video camera such as an endoscope and inputting it as a digital image signal to a computer, a timing at which an operator views a monitor image and captures an image. A frame memory for periodically updating and storing N (N is 2 or more) frames of digital data of time-series image data being monitored, At the time when the operation is performed, the time-series image data is fetched and updated into the frame memory for a predetermined number of frames, then stopped (frozen), and the image stored in the frame memory is stopped. Selects only the specified image as a valid image from images including images stored before the trigger operation time An image capturing apparatus comprising:

<Embodiment 2> In an image capturing apparatus for A / D converting an image output signal of a video camera such as an endoscope and inputting it as a digital image signal to a computer, a timing at which an operator views a monitor image and captures an image. A frame memory for periodically updating and storing N frames of digital data of the time-series image data being monitored, and a means for designating a capture cycle thereof. By appropriately selecting a frame image that is retroactive from the time when the external trigger operation is performed from among the images stored in the frame memory, it is possible to reduce an input of a defective image due to a delay in operation or blurring in imaging of a video camera. The image capturing device according to the first embodiment, which enables the following.

<Embodiment 3> In an image capturing apparatus for A / D converting an image output signal of a video camera such as an endoscope and inputting it as a digital image signal to a computer, an operator views a monitor image and captures the image. A frame memory for periodically updating and storing N frames of digital data of the time-series image data being monitored, and a means for designating a capture cycle thereof. By providing a means for automatically selecting a frame image that has been traced back by a predetermined time or a predetermined number of frames from the time when the external trigger operation is performed, from the images stored in the frame memory, it is possible to provide an external trigger that is predicted in advance. The image capturing device according to the first embodiment, wherein delay of a switch operation or the like can be compensated. Place.

<Embodiment 4> In an image capturing apparatus for A / D converting an image output signal of a video camera such as an endoscope and inputting it as a digital image signal to a computer, an operator views a monitor image and captures the image. And a frame memory for periodically updating and storing digital data of N frames of time-series image data being monitored, and a time point when the external trigger operation is performed. Then, after taking the update of the time-series image data into the frame memory for a predetermined number of frames and then stopping (freezing),
The image processing apparatus further includes a calculation output unit that sets only an image obtained by averaging an arbitrary number of frames for each pixel unit from among the images stored in the frame memory as an effective image, thereby reducing noise in a still image and improving image quality. An image capturing device capable of outputting image quality.

[0036]

As described above, according to the present invention, an image output signal of a video camera of an endoscope or the like is output from the image including the image before the trigger operation by the operator viewing the monitor image. Can be easily captured, and a high-quality image filing can be performed by capturing necessary images at a high rate without having to be skilled in operations such as image capturing timing. If the timing does not matter much, it is possible to select a better image with few defects such as a local halation image from the images stored in the frame memory.

Further, by operating a video camera such as an endoscope, the video camera is stopped for a short time (to reduce blurring) for observing an affected part, etc., as compared with an analog monitor image directly observed, thereby obtaining a digital image signal. By using a number of time-series frame image signals, digital image signal processing such as pixel averaging and filtering can obtain a high-quality image with reduced random noise. Visual observation can be made possible.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram showing an image capturing device according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating an image capturing operation according to an embodiment of the present invention.

FIG. 3 is a flowchart showing an example of a magneto-optical disk filing operation including a noise reduction processing flow of a captured image according to another embodiment of the present invention.

[Explanation of symbols]

1: video camera, 2: monitor SW, 3: video monitor, 4: A / D converter, 5: trigger switch, 6: controller, 7: frame memory (7-1: FM1, 7-)
2: FM2, 7-3: FM3), 8: MPX (frame switching circuit), 9: D / A converter, 100: CPU (computer), 101: BUSA (bus adapter), 10
2: magnetic disk device, 103: MM (main memory), 1
04: magneto-optical disk drive, 110: local bus, 1
20: System bus.

Claims (4)

[Claims] 1. An image capturing device for inputting an image signal of a video camera operated by an operator to a computer as a digital image signal, wherein a monitor for displaying the image signal of the video camera and a timing for capturing the image signal are designated. An external trigger means, and a frame memory for storing a digital image signal of N frames or more obtained by converting an image signal of the video camera into a digital signal, wherein when the timing of capturing the image signal is instructed by the external trigger means, By stopping the capture of the digital image data into the frame memory after updating it by the predetermined number of frames, the timing before and after the timing triggered by the timing instruction by the external trigger means stored in the frame memory is performed. Multiple digital images Image capturing apparatus characterized by the selectably configure any image from over data. 2. A method according to claim 1, further comprising: designating means for designating a writing cycle to a frame memory for storing the digital image signals of N frames or more. 2. An arbitrary image can be selected from a plurality of digital image data stored in a frame memory according to the writing cycle before and after the timing when the timing instruction is issued by the means. An image capturing device according to any of the preceding claims. 3. A means for automatically selecting an image which has been traced back by the number of frames due to a predetermined operation delay of an external trigger when selecting an arbitrary image from a plurality of digital image data stored in the frame memory. The image capturing apparatus according to claim 1 or 2, wherein an operation delay of the external trigger means which is expected in advance is compensated. 4. When a desired image is selected from a plurality of digital image data stored in the frame memory, a still image is selected by averaging images of a desired number of frames for each pixel unit. 3. The image capturing device according to claim 1, wherein noise of the image is reduced to enable high-quality output.