JPH0956707A - Method for image processing, processor x-ray fluoroscopic equipment and radiographic equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the influence of blurring caused by body motion of a subject by means of adding operation of plural images setting a range for adding operation in which a deviation does not exceed a standard value by selecting an object image in the objective range in the direction apart from a standard image and by aligning both images. SOLUTION: A frame adding processing unit 21 conducts frame adding processing by using a recursion filter and improves the SN ratio of the image data by adding in a given ratio an image data of adjacent frames in the time base direction in still images having a high correlation between frames. A motion correction unit 23 conducts alignment of the image data from a memory 22 with the image data of the standard image ordered from a control unit 1. A frame adding operation unit 24 receives the image data and treats in the same way as the frame adding operating unit 21. A switch 25 switcher to the out put of the frame adding operation unit 21 or the output of the frame adding operation unit 25, based on the order from the control unit 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing method, an image processing apparatus, an X-ray fluoroscopic imaging apparatus, and an X-ray imaging apparatus. More specifically, the present invention relates to a method for improving image quality by adding a plurality of image data. The present invention relates to an improvement for obtaining a good image by processing in a state where the image data shift due to is corrected.

[0002]

2. Description of the Related Art FIG. 7 shows the structure of an X-ray fluoroscopic apparatus using a conventional X-ray television system. In the X-ray fluoroscope having the configuration shown in FIG. 7, the high voltage generator 3 generates a predetermined high voltage under the control of the X-ray controller 2 according to an instruction from the controller 1, and the high voltage causes the X-ray tube 4 to move. X-ray irradiation is required. Then, the perspective image of the subject 6 on the top plate 5 is made visible and enhanced by an image intensifier (Image Intensifier: II) 7, and the visible image is enhanced by the television camera 8.
To image. Then, the video signal from the television camera 8 is converted by the A / D converter 9 into image pickup data (image data) as digital data, and the image processing unit 10 performs various necessary image processing. The image-processed image pickup data is converted into an analog video signal by the D / A converter 11, and is supplied to the display unit 12 to display a perspective image. Instructions for performing such an operation are given on the operation unit 13.
Is being given more.

In order to perform film photographing of the X-ray fluoroscopic image at an arbitrary timing, a photographing unit (not shown) is arranged so as to perform film photographing. An X-ray fluoroscope that digitally processes the imaged image as described above is a digital radiograph (Digital Radiograph).
y) Sometimes referred to as a device or simply a DR device.

[0004]

In such an image processing apparatus, in order to prevent melting of a focal track (a surface generating X-rays) when the anode temperature of the X-ray tube 4 rises, It is necessary to reduce the tube current of the X-ray tube 4.

On the other hand, the optimum condition for photographing is generally determined by mA · S when the tube current is mA and the exposure time is S. Therefore, when the tube current mA is reduced as described above, the exposure time S can be lengthened to maintain the optimum condition.

However, if the exposure time S is lengthened, the image may be blurred due to the movement of the subject. The body movement speed of the subject is said to be 6.6 mm / sec. On the other hand, in order to perform shooting with sufficient sharpness, 1
It is known that the amount of movement for each shooting should be about 0.2 mm. Therefore, the shooting time is 0.2 (mm) /6.6 (mm
/Sec)=0.030 sec, that is, about 30 msec.

Therefore, if one shooting can be performed in 30 msec or less, it becomes possible to suppress the influence of blur due to body movement. However, as described above, when the tube current mA is reduced,
There is a problem that a sufficient amount of X-ray cannot be obtained within this time.

Therefore, one of the video signals from the TV camera is
Considering that the frame is about 30 msec, it is conceivable to add the image data for each frame (hereinafter, referred to as a frame addition process) to reduce noise.

With respect to such noise reduction, it is widely used in various image processing fields because a noise reduction effect by frame correlation can be sufficiently obtained for a still image or an image with little motion.

However, since it is difficult to obtain the effect of noise reduction due to frame correlation for a moving image,
It is generally performed in various types of image processing to determine that the image is a moving image and stop the frame addition processing when motion is detected even in a part of the image data.

Therefore, when the influence of body movement is taken into consideration, it cannot be used as it is in an X-ray fluoroscopic apparatus, or a sufficient effect cannot be obtained. The present invention has been made to solve the above various problems, and an object thereof is to improve image quality by performing image processing while suppressing the influence of blurring due to body movement of the subject. An image processing method, an image processing apparatus, an X-ray fluoroscopic imaging apparatus, and an X-ray imaging apparatus.

[0012]

Accordingly, the invention as a means for solving the problem is described below. First
The present invention is an image processing method for improving the image quality by adding and synthesizing a plurality of images captured consecutively in time, wherein an image processing method is performed from an image adjacent to a preset reference image in a direction away from the reference image. Select the target image within the range, compare the target image with the reference image, align the target images so that the target image is closest to the reference image, and shift the aligned target image from the reference image. This is an image processing method in which an addition / synthesis range is set in a range that does not exceed the given reference value, and a plurality of images are additively synthesized in the set addition / synthesis range.

In the first aspect of the invention as described above, the selected target image and the reference image are aligned with each other, and the addition and synthesis range is set within a range in which the deviation does not exceed the reference value to synthesize the target image.

As a result, it becomes possible to carry out additive synthesis while suppressing the influence of blurring due to the body movement of the subject, and to improve the image quality. In addition, it is preferable to perform the alignment at a plurality of preset positions inside the target image and the reference image in order to perform the alignment accurately. As a result, even if a part of the image moves, the position can be effectively aligned, and the effect of improving the image quality can be sufficiently obtained.

A second aspect of the present invention is an image processing apparatus for improving the image quality by adding and synthesizing a plurality of images captured continuously in time, wherein a reference image is extracted from an image adjacent to a preset reference image. Selecting means for selecting a target image within the target range in a direction away from the target image, and aligning means for aligning the target image so that the target image is closest to the reference image by comparing the target image with the reference image; Deviation calculating means for calculating a deviation between the matched target image and reference image,
Image processing characterized by including range setting means for setting an addition composition range within a range in which a deviation does not exceed a given reference value, and addition processing means for additively combining a plurality of images within the set addition composition range. It is a device.

In the second aspect, the selected target image and the reference image are aligned with each other, and the addition and synthesis range is set within a range in which the deviation does not exceed the reference value to synthesize the target image.

This makes it possible to perform additive synthesis while suppressing the influence of blurring due to the body movement of the subject, and to improve the image quality. In addition, it is preferable that the alignment means aligns the target image and the reference image at a plurality of preset positions in order to accurately perform the alignment. As a result, even if a part of the image moves, the position can be effectively aligned, and the effect of improving the image quality can be sufficiently obtained.

A third aspect of the present invention is an X-ray fluoroscopic imaging apparatus for adding and synthesizing a plurality of images continuously obtained in time by X-ray fluoroscopy to synthesize a photographic image. Holding means for holding a plurality of perspective images as a reference,
From the image adjacent to the reference image at the time when the shooting instruction was given,
Selecting means for selecting the target image within the target range in a direction away from the reference image; and alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image with the reference image. , A deviation calculating means for obtaining a deviation between the aligned target image and the reference image, a range setting means for setting an addition combining range within a range in which the deviation does not exceed a given reference value, and a set addition combining range. An X-ray fluoroscopic imaging apparatus comprising: an addition processing unit that adds and combines a plurality of images to combine captured images.

In the third aspect of the invention as described above, the target image selected based on the time when the X-ray imaging instruction is made and the predetermined reference image are aligned with each other, and the deviation is within a range not exceeding the reference value. A target image is synthesized by setting an addition synthesis range, and a captured image is synthesized from a plurality of images obtained by X-ray fluoroscopy.

As a result, it becomes possible to combine a photographed image from a plurality of images obtained by X-ray fluoroscopy while suppressing the influence of blurring due to the body movement of the subject, and it is possible to improve the image quality. .

It is preferable that the alignment means aligns the target image and the reference image at a plurality of preset positions for accurate alignment. As a result, even if a part of the image moves, the position can be effectively aligned, and the effect of improving the image quality can be sufficiently obtained.

A fourth aspect of the present invention is an X-ray radiographing apparatus for adding and synthesizing a plurality of images obtained during X-ray exposure to generate an image in which blurring due to movement of the subject is suppressed. A capturing unit that captures a plurality of images in a time-division manner, and a selecting unit that selects a target image within a target range in a direction away from the reference image from images adjacent to a preset reference image among the captured images. And comparing the target image and the reference image so that the target image comes closest to the reference image, and a shift calculation for obtaining a shift between the aligned target image and the reference image Means, range setting means for setting an addition composition range within a range not exceeding a given reference value, and addition processing means for additively combining a plurality of images within the set addition composition range. X-ray photography It is the location.

In the fourth aspect of the invention as described above, the target image time-divided from the image during X-ray exposure and the predetermined reference image are aligned with each other so that the deviation does not exceed the reference value. By setting the additive combination range and combining the target images, the multiple images obtained during X-ray exposure are additively combined to generate an image in which blurring due to movement of the subject is suppressed.

As a result, it becomes possible to carry out X-ray photography while suppressing the influence of blur due to the movement of the subject. In addition, it is preferable that the alignment means aligns the target image and the reference image at a plurality of preset positions in order to accurately perform the alignment. As a result, even if a part of the image moves, the position can be effectively aligned, and the effect of improving the image quality can be sufficiently obtained.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a flowchart showing a processing procedure of an image processing method of the present invention, and FIG. 2 is a configuration diagram showing a configuration of an apparatus for executing the image processing method.
The entire apparatus shown in FIG. 2 constitutes the X-ray fluoroscopic imaging apparatus or the X-ray imaging apparatus of the present invention, and the central portion thereof also constitutes the image processing apparatus of the present invention.

First, the configuration and basic operation of an X-ray fluoroscopic imaging apparatus or an X-ray fluoroscopic imaging apparatus (hereinafter referred to as an X-ray fluoroscopic imaging apparatus as an apparatus for performing at least one of fluoroscopy and imaging) will be described. To do. In FIG. 2,
The same parts as those in FIG. 7 for explaining the conventional example are denoted by the same reference numerals.

In the X-ray fluoroscopic apparatus having the structure shown in FIG. 2, the high voltage generator 3 generates a predetermined high voltage under the control of the X-ray controller 2 according to an instruction from the controller 1, and the high voltage causes the high voltage to be generated. The X-ray tube 4 performs the necessary X-ray irradiation.

Then, a perspective image of the subject 6 placed on the top plate 5 is converted into an image intensifier (Image Intensif).
ier: II) 7 forms a visible image and enhances the image, and the visible image is captured by the television camera 8.

Then, the video signal from the television camera 8 is converted by the A / D converter 9 into image pickup data (image data) as digital data, and the image processing unit 2 to be described later.
At 0, various image processings required are performed.

The image-processed image pickup data is returned to an analog video signal by the D / A converter 11 and supplied to the display section 12 to display a perspective image. Here, the image processing unit 20 will be described. First,
The frame addition processing unit 21 in the image processing unit 20 will be described.

During X-ray fluoroscopy, the noise contained in the image data of the imaged image is reduced to reduce S
In order to improve the N ratio (Signal to Noise Ratio), frame addition processing using a recursive filter is performed.

The frame addition process is a process for improving the SN ratio of image data by adding image data of adjacent frames in the time axis direction at a predetermined ratio in a still image having a high correlation between frames.

The frame addition processing is performed by the frame addition processing circuit 21. That is, the input image data is multiplied by (1-a) by the coefficient from the control unit 1, and the image data of one frame before is added by being multiplied by a and output.

The coefficient a in this case is in the range between 0 and 1, and when a = 0, the frame addition processing is stopped,
When a has a predetermined value, the SN ratio improving effect is maximized. In this case, since it is a process of adding two-dimensional (X-axis and Y-axis) image data in the time axis direction, it may be called a three-dimensional image process in view of the processing content.

As the constant a for the past image data of frame addition increases, the ratio of the past image data increases, so that afterimage (lag) occurs when moving image data is input. Occurrence may be a problem.

In such frame addition processing, for image data having the same SN ratio, a = 0.
Consider the case where the ratios of 5 and 5 are added at the same ratio. In this case, the noise phase and amplitude are random (no frame correlation), so the noise components are added and +3
In contrast to dB, the phase and amplitude of the signal are equal (there is frame correlation), so the signal components are added to give +6 dB. Therefore, as a result, the SN ratio is improved by 3 dB.

Next, a configuration for performing frame addition processing in conformity with motion will be described. The frame memory 22 is a frame memory having a storage capacity of n frames. Here, n is 2 or more, but as n increases, the image quality improving effect described later increases. Motion correction processing unit 23
Is for aligning the image data from the frame memory with the image data of the reference image instructed by the control unit 1. The frame addition processing unit 24 has the same configuration as the frame addition processing unit 21 described above.
Since the frame addition processing unit 24 is supplied with the aligned image data, it is not necessary to consider the influence of the afterimage, so that the optimum value can be used as the coefficient a described above. The switch 25 is a switching unit that switches between the output of the frame addition processing unit 21 and the output of the frame addition processing unit 24 based on an instruction from the control unit 1.

Here, a basic processing procedure for improving image quality relating to digital radiography of the image processing apparatus of the present invention will be described with reference to the flowchart of FIG. First, according to an instruction from the control unit 1, X-ray irradiation is performed from the X-ray tube 4. In parallel with this, image data of a plurality of X-ray fluoroscopic images is obtained at different timings (step 1 in FIG. 1) and stored in the frame memory 22 (step 2 in FIG. 1).

An example of this X-ray irradiation and the timing of obtaining image data is shown in FIG. In the case of continuous irradiation as shown in FIG. 3A, the image data is acquired and stored in the frame memory 22 at each time within the range where the influence of the motion of the subject does not cause the blur. Also, intermittently X
In the pulsed X-ray system for performing X-ray irradiation, the X-ray irradiation is set as a time within a range where the influence of the motion of the subject as described above does not occur, and sampling of image data and frame memory are performed for each X-ray irradiation. 22 is stored.

Such storage and X-ray irradiation (for example, X
The control unit 1 gives an instruction to each unit to execute (for time-division capturing of a plurality of images during line exposure). Therefore,
The control unit 1 operates as a capturing means.

In this case, it has been described that the time within the range where the influence of the body movement does not occur is preferably 30 msec or less in relation to the body movement. This 30 ms is NTS
It is approximately equal to the time of one frame in a television camera and a television receiver that handle a video signal of the C (National Television System Committee) system. Therefore, when the existing television camera, frame memory, and their control devices are used, 30 msec is used.

The image data of a plurality of frames are successively stored in the frame memory 22 as described above. When the capacity of the frame memory 22 is n frames, the latest n frames of image data are sequentially acquired. Be stored.

FIG. 4 schematically shows the state of the image data Di-5 to Di + 5 when n = 11. When there is an instruction to improve the image quality from the control unit 1, the image data sampled at that timing is set as the reference image Di. Then, before and after (n
-1) / 2 image data Di-1 to Di-5 and Di +
1 to Di + 5 are stored. Note that n
Storing the image data of the image to be held by determining or instructing corresponds to the selection of the target image.

Then, the motion correction unit 23 detects the motion of the image data to be subjected to the frame addition processing and aligns the position (step 3 in FIG. 1). This motion detection and alignment is performed in consideration of the characteristics of the body motion of the subject under fluoroscopy. In other words, instead of performing a batch process (parallel movement of image data) on the entire screen like the conventional camera-camera shake prevention, a moving area is found in the image data and the amount of movement for each area is determined. So that it can be aligned.

FIG. 5 is a schematic explanatory view showing a state of motion detection of image data. For example, consider the case where the motion detection is performed on Di of the reference image and Di-1 adjacent to this. In that case, each image data is m × m
The area is divided into rectangular blocks (4 × 4 is shown here), and pixels are cross-correlated for each corresponding block of Di and Di−1. Then, the positions of the blocks that maximize the coefficient obtained by the cross-correlation are obtained. Here, the position where the coefficient obtained by the cross-correlation becomes maximum in each of the 16 blocks of FIG. 5A and FIG. 5B is obtained.

FIG. 6A shows the image data D of the reference image.
The center points of the 16 regions of i are shown. And FIG.
(B) shows a state in which the center position of each block of the image data Di-1 is moved in accordance with the movement that maximizes the coefficient obtained by the cross-correlation. FIG.
In (b), the central positions of the blocks are connected by a line (a state indicating a positional deviation).

Therefore, when the frame addition processing described later is executed, on the image data side to be added to the image data of the reference image, all pixels are obtained by image interpolation from the movement amount of the peripheral center position. Positioning is performed according to the amount of movement. Regarding this alignment, a method of adjusting the read address at the time of reading for the frame addition processing and simultaneously reading each pixel of FIG. 6A and each corresponding pixel of FIG. 6B, A method of pre-storing in another area of the frame memory before the frame addition processing so as to correct the shift state of FIG. 6B can be considered.

When such alignment is performed, the residual difference Σ (Di + j-Sj) in each image data is obtained.
² is obtained by the motion processing unit 23, and for the image data whose residual exceeds a certain value, the frame addition process described later is stopped by an instruction from the control unit 1 (step 4 in FIG. 1). Alternatively, it is also possible to stop the frame addition process described below for image data having a block whose coefficient obtained by the above-described cross-correlation at the time of alignment does not reach a certain value. By doing so, it is possible to exclude the image data whose motion amount is too large.

The motion processing unit 23 for obtaining the residual error in this way
Constitute the alignment means and the deviation calculation means.
Further, the control unit 1 that decides to cancel frame addition based on this residual constitutes a range decision means that decides the addition and synthesis range.

Then, the aligned image data are subjected to frame addition processing and combined (step 5 in FIG. 1). Here, Di = S0 and Sj = Sj-1 + Di-
The operation of 1 + Di + 1 is executed for j = 1,2,3,4,5.
That is, the frame addition processing is performed on the image data of the adjacent frame with respect to the image data of the reference image,
This is sequentially spread to the image data on both sides (FIG. 1, steps 5, 6, and 7).

In this case, the frame addition processing is executed on the image data of the reference image with five pieces of image data, but the number is not limited to this. Further, even when the frame addition processing is executed with the same number of image data, it is better to execute the frame addition processing with ± (n-1) / 2 pieces of image data with the image data of the reference image as the center. Since the time difference from the reference image is smaller than that in the case where the frame addition processing is performed only with the n-1 image data on the side of, the effect of body movement is reduced and the processing accuracy is improved.

In this way, when the frame addition processing for the image data of all the images stored in the frame memory 22 is completed, the switch 25 is switched to the frame addition processing section 24 side by an instruction from the control section 1. The D / A converter 11 converts the image data that has been switched and subjected to the frame addition processing into an analog video signal and displays the image on the display unit 12.

If the frame memory in the frame addition processing unit 24 is a dual-port memory or the like capable of writing and reading in parallel, the image data during the frame addition processing is read and displayed on the display unit 12. It is also possible to do so.

Then, until the control section 1 gives an instruction or for a certain period of time, the influence of the body movement is eliminated and the image data subjected to the frame addition processing is continuously displayed. During such a display, rewriting is started so that the latest n frames of image data are sequentially stored in the frame memory 22 to prepare for the next frame addition process.

Further, such a frame addition processing unit 24
During the period other than displaying the image data from
The image data processed in the same manner as the conventional one in the frame addition processing 21 is displayed on the display unit 12. Alternatively, it is possible to omit the frame addition processing unit 21 and display the image data that is not processed at all.

As described above, the image processing method and the image processing are performed in which the selected target image and the reference image are aligned with each other, and the addition and synthesis range is set within the range in which the deviation does not exceed the reference value to synthesize the target image. By applying the device to an X-ray fluoroscopic imaging device, it is possible to suppress the influence of blurring due to the body movement of the subject and
It is possible to combine a captured image from a plurality of images obtained by fluoroscopy and improve image quality.

Similarly, by applying the image processing method and the image processing apparatus shown in the above-described embodiments to an X-ray imaging apparatus, a plurality of images obtained during X-ray exposure are added and combined to be combined. Since it is possible to generate an image in which blurring due to the movement of the specimen is suppressed, it is possible to perform X-ray imaging in which the influence of the blurring due to the movement of the subject is suppressed.

In addition, in each of the above embodiments, the frame addition processing unit 2 is used even when the X-ray irradiation is temporarily interrupted.
By continuing to read the image data from No. 4, the output of the captured image is not interrupted. Further, since the X-ray tube current can be reduced, there is an advantage that the inspection can be executed with a small dose. Further, the capacity of the X-ray generation power source used in the high voltage generation unit 3 can be suppressed to a small value. In addition, since the dose of X-rays is suppressed, the X-ray tube 4
There is also an advantage that the device can be miniaturized, such as eliminating the need for an iris diaphragm around the.

As described in detail above, it is an image processing method for improving the image quality by adding and synthesizing a plurality of images which are taken consecutively in time, and from an image adjacent to a preset reference image, Select the target image within the target range in the direction away from the reference image, compare the target image and the reference image, align the target image so that the target image is closest to the reference image, and align the target image According to the invention of the image processing method, the deviation between the reference image and the reference image is obtained, the addition composition range is set in a range not exceeding the given reference value, and a plurality of images are additively combined in the set addition composition range.
It is possible to perform frame addition processing while suppressing the influence of blurring due to body movement of the subject, and it is possible to improve image quality. Further, since the processing is performed in a state where the image data having a large influence of blurring is excluded, the effect of improving the image quality is great.

Further, an image processing apparatus for improving the image quality by adding and synthesizing a plurality of images picked up continuously in time, in the direction away from the reference image from the image adjacent to the preset reference image. Selecting means for selecting a target image within the target range; alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image with the reference image; and the aligned object A deviation calculating means for obtaining a deviation between an image and a reference image, a range setting means for setting an addition composition range within a range where the deviation does not exceed a given reference value, and a plurality of images are additively combined in the set addition composition range. The invention of the addition processing means and the image processing apparatus provided also makes it possible to perform the frame addition processing while suppressing the influence of blurring due to the body movement of the subject, thereby improving the image quality. It becomes ability. Further, since the processing is performed in a state where the image data having a large influence of blurring is excluded, the effect of improving the image quality is great.

Further, a plurality of images continuously obtained in time by X-ray fluoroscopy are added and synthesized to synthesize a photographed image X.
A fluoroscopic imaging apparatus, which holds a plurality of fluoroscopic images with reference to a time when an imaging instruction is given, and a target in a direction away from the reference image from an image adjacent to the reference image at the time when the imaging instruction is given. Selection means for selecting the target image within the range, alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image and the reference image, and the aligned target image And a reference image, a deviation calculation means for obtaining a deviation between the reference image and a reference image, a range setting means for setting an addition and combination range within a range where the deviation does not exceed a given reference value, and an addition for adding and combining a plurality of images within the set addition and combination range A processing means, and X for synthesizing a captured image
According to the invention of the fluoroscopic imaging apparatus, the target image selected on the basis of the time when the X-ray imaging instruction is performed and the predetermined reference image are aligned, and the additive synthesis is performed within a range in which the deviation does not exceed the reference value. A target image can be synthesized by setting a range, and a captured image can be synthesized from a plurality of images obtained by X-ray fluoroscopy, and a plurality of X-ray fluoroscopy images can be obtained while suppressing the influence of blurring due to body movement of the subject. Therefore, it is possible to improve the image quality by combining captured images. Further, even if a part of the image moves, the alignment can be effectively performed, and the effect of improving the image quality can be sufficiently obtained.

An X-ray photographing apparatus for adding and synthesizing a plurality of images obtained during X-ray exposure to generate an image in which blurring due to the movement of the subject is suppressed, From the capturing means that captures in a time-division manner and the image adjacent to the preset reference image among the captured images,
Selecting means for selecting the target image within the target range in a direction away from the reference image; and alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image with the reference image. , A deviation calculating means for obtaining a deviation between the aligned target image and the reference image, a range setting means for setting an addition combining range within a range in which the deviation does not exceed a given reference value, and a set addition combining range. According to the invention of the radiographic apparatus provided with the addition processing means for additively synthesizing a plurality of images, the target image captured in time division from the image during X-ray exposure and the predetermined reference image are aligned. ,
An image in which blurring due to movement of the subject is suppressed by additively synthesizing multiple images obtained during X-ray exposure by setting an additive synthesizing range within a range in which the deviation does not exceed the reference value and synthesizing the target images. Since it is possible to generate X, it is possible to perform X-ray imaging in which the influence of blur due to the movement of the subject is suppressed. Even if a part of the image moves, the position can be effectively aligned, and the effect of improving the image quality can be sufficiently obtained.

[0063]

As described above in detail, the selected target image and the reference image are aligned with each other, and the addition and synthesis range is set within a range in which the deviation does not exceed the reference value to synthesize the target image. According to the invention of the image processing method, it is possible to perform additive synthesis while suppressing the influence of blurring due to body movement of the subject, and it is possible to improve image quality.

According to the invention of the image processing apparatus, the selected target image and the reference image are aligned with each other, and the addition and synthesis range is set within a range in which the deviation does not exceed the reference value to synthesize the target image. As a result, it is possible to perform additive synthesis while suppressing the influence of blurring due to body movement of the subject, and it is possible to improve image quality.

Further, the target image selected on the basis of the time when the X-ray radiography is instructed and the predetermined reference image are aligned, and the addition and synthesis range is set within the range in which the deviation does not exceed the reference value. According to the invention of an X-ray fluoroscopic imaging apparatus that synthesizes target images and synthesizes captured images from a plurality of images obtained by X-ray fluoroscopy, it is possible to obtain by X-ray fluoroscopy while suppressing the influence of blurring due to body movement of the subject. It is possible to combine a captured image from the acquired plural images, and it is possible to improve the image quality.

Then, the target image captured in time-division from the image during X-ray exposure is aligned with a predetermined reference image, and the addition and synthesis range is set within a range in which the deviation does not exceed the reference value. According to the invention of the X-ray imaging apparatus that synthesizes the target image, it is possible to add and synthesize a plurality of images obtained during X-ray exposure to generate an image in which blurring due to movement of the subject is suppressed. It is possible to perform X-ray imaging while suppressing the influence of blur due to the movement of the sample.

[Brief description of drawings]

FIG. 1 is a flowchart showing a procedure of an image processing method of the present invention.

FIG. 2 is a configuration diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention.

FIG. 3 is a time chart showing the timing of X-ray irradiation and the timing of sampling image data.

FIG. 4 is an explanatory diagram showing a state of image data stored in a frame memory for frame addition processing.

FIG. 5 is an explanatory diagram showing a state in which image data is divided into a plurality of blocks for motion detection.

FIG. 6 is an explanatory diagram showing a positional deviation detected by motion detection.

FIG. 7 is a configuration diagram showing a configuration of a conventional image processing apparatus.

[Explanation of reference symbols] 1 control unit 2 X-ray control unit 3 high-voltage generation unit 4 X-ray tube 5 top plate 6 subject 7 image intensifier 8 television camera 9 A / D converter 11 D / A converter 12 display unit 20 image processing unit 21 frame addition processing unit 22 frame memory 23 motion correction unit 24 frame addition processing unit

Claims (5)

[Claims] 1. An image processing method for improving image quality by adding and synthesizing a plurality of images captured continuously in time, wherein the image is adjacent to a preset reference image in a direction away from the reference image. Select a target image within the target range, compare the target image and the reference image, align the target images so that the target image is closest to the reference image, and shift the aligned target image and the reference image. The image processing method in which the addition combined range is set within a range where the deviation does not exceed the given reference value, and a plurality of images are added and combined within the set combined range. 2. An image processing device for improving image quality by adding and synthesizing a plurality of images captured continuously in time, wherein the image processing device is arranged in a direction away from an image adjacent to a preset reference image. Selection means for selecting a target image within the target range, alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image and the reference image, and the aligned target A deviation calculation means for obtaining a deviation between an image and a reference image, a range setting means for setting an addition composition range within a range where the deviation does not exceed a given reference value, and an addition composition of a plurality of images in the set addition composition range. An image processing apparatus comprising: an addition processing unit. 3. The image processing apparatus according to claim 2, wherein the alignment means aligns the target image and the reference image at a plurality of preset positions. 4. An X-ray fluoroscopic imaging apparatus for synthesizing photographed images by additively synthesizing a plurality of images obtained in time series by X-ray fluoroscopy, wherein a plurality of images are taken on the basis of a time when an instruction is given From the holding means for holding the fluoroscopic image and the image adjacent to the reference image at the time when the shooting instruction is given,
Selecting means for selecting the target image within the target range in the direction away from the reference image; and alignment means for aligning the target image so that the target image is closest to the reference image by comparing the target image with the reference image. , A deviation calculation means for obtaining a deviation between the aligned target image and the reference image, a range setting means for setting an addition composition range within a range in which the deviation does not exceed a given reference value, and a set addition composition range. An X-ray fluoroscopic imaging apparatus comprising: an addition processing unit configured to add and combine a plurality of images to combine captured images. 5. An X-ray imaging apparatus for adding and synthesizing a plurality of images obtained during X-ray exposure to generate an image in which blurring due to the movement of a subject is suppressed, the plurality of images during X-ray exposure. A capturing means for capturing the images in a time-division manner, a selecting means for selecting a target image within a target range in a direction away from the reference image from an image adjacent to a preset reference image among the captured images, and the target image And a reference image, so that the target image is closest to the reference image, a registration means for aligning the target image, and a deviation calculating means for calculating a deviation between the aligned target image and the reference image, Is provided with range setting means for setting an addition composition range within a range not exceeding a given reference value, and addition processing means for additive composition of a plurality of images within the set addition composition range. Imaging device.