JP3028626B2 - X-ray fluoroscopic image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray fluoroscopic image processing apparatus for processing an X-ray fluoroscopic image obtained by an X-ray TV fluoroscopic system. The present invention relates to an X-ray fluoroscopic image processing apparatus that performs image processing.

[0002]

2. Description of the Related Art An X-ray TV fluoroscopy system converts an X-ray fluoroscopic image obtained by irradiating an X-ray from an X-ray tube into a video signal by combining an image intensifier and a TV camera, and converts this into a video signal. Sent to the device for display,
What you observe. Conventionally, in this X-ray TV fluoroscopy system, the last fluoroscopic image is stored in a frame memory or the like when the X-ray fluoroscopy is ended in order to reduce the exposure of the patient to X-rays, and the reproduction is ended. A so-called last frame memory processing method of displaying a perspective image later is often used. At this time, since a fluoroscopic image has a large amount of quantum noise to be obtained with a small amount of X-ray, noise reduction processing such as integration processing is often performed for recording and reproduction of the fluoroscopic image.

[0003]

However, in the prior art, since only integration processing is performed, there is a problem that only a noise reduction effect is obtained and the contrast of an image is insufficient. In particular, in a part where a bright part such as a lung field and a dark part such as a heart coexist, such as a chest, it is difficult to read a fine structure part which is superimposed on both parts. In such a case, it is desired that contrast processing for simultaneously displaying fine structures coexisting on both sides be automatically performed, and unsharp masking processing can be considered as such processing, but the processing time is long. There is.

An object of the present invention is to provide an X-ray fluoroscopic image processing apparatus capable of easily obtaining a high-contrast unsharp masking image in which a fine structure can be easily observed, in a short time.

[0005]

In order to achieve the above object, in an X-ray fluoroscopic image processing apparatus according to the present invention,
An integrated image is obtained by adding the video signals of the X-ray fluoroscopic image while matching the corresponding pixel positions in a plurality of frames, and a blurred image is obtained by adding the video signals while shifting the corresponding pixel positions. It is characterized in that these are weighted and then subtracted.
Since the creation of the integral image and the creation of the blurred image can be performed simultaneously and in parallel, these images can be obtained at a high speed, and the unsharp masking image can be obtained in as short a time as the conventional integration process alone. Can be obtained.

[0006]

An embodiment of the present invention will be described below in detail with reference to the drawings. In FIG. 1, video signals of X-ray fluoroscopic images are sequentially transmitted frame by frame from a TV camera of an X-ray fluoroscopic TV system (not shown).
This video signal is converted into a digital signal in the A / D converter 2. At the time of normal fluoroscopy, this digital signal is sent to the window processor 3 via the switch 1 tilted to the b side, and window processing (a kind of gradation conversion) in which only a predetermined window of the gradation is emphasized. ). Thereafter, the signal is returned to an analog video signal via the D / A converter 4 and sent to a TV monitor device (not shown) for display.

When a see-through switch (not shown) is turned off, the digitized image data is added to the output data of the frame memories 5 and 6 by the adders 7 and 8 and written into the frame memories 5 and 6 again. That is, even after the fluoroscopic switch is turned off, X-ray irradiation is performed for a while and a video signal of an X-ray fluoroscopic image is sent, and the image data is stored in the frame memory 5 as described above. 6 is written.

The addresses of the frame memories 5 and 6 are controlled by a memory address controller 12.
When image data of a new frame is sent to the adder 7, data of a pixel position corresponding to each pixel is read out from the frame memory 5. As a result, data is added for each pixel while matching the positions of the corresponding pixels, and the data after the addition is written to the frame memory 5. Therefore, the image is integrated in the time direction, and an integrated image is formed in the frame memory 5.

On the other hand, the read addresses of the frame memory 6 are shifted in the vertical and horizontal directions. That is, the adder 8 does not add the pixel data at a certain position of the input image data and the pixel data at the same position of the image data read from the frame memory 6, but adds the pixel data at a shifted position. . As a result, it is possible to perform a process (so-called shift integration) in which the entire images are superimposed while being shifted, and a blurred image can be created in the frame memory 6.

After the simple integration and the shift integration in the frame memories 5 and 6 are completed, the image data of the integrated image and the image data of the blurred image formed by the integration are weighted by multipliers 9 and 10, respectively. Then, these weighted image data are sent to the subtractor 11, where the corresponding pixel data are subtracted from each other. At this time, the output data of the subtractor 11 is sent to the window processor 3 via the switch 1 that is tilted to the side a. The window processing in the window processor 3 is the same as that in the above-described fluoroscopy, and is thereafter returned to an analog video signal via the D / A converter 4 and sent to a TV monitor device (not shown) for display. The same is true for

As described above, since the blurred image is subtracted from the integral image, an unsharp masking process is performed, and an image with high contrast can be obtained. In addition, since the creation of the integral image and the creation of the blurred image are performed simultaneously and in parallel, the processing time does not take longer than in the case of only the conventional integration processing.

In the above-described embodiment, the unsharp masking processing is performed in the so-called last frame memory processing at the end of the fluoroscopy. However, the present invention is not limited to such a last frame memory processing. Such processing can be performed by, for example, the following.

[0013]

As described above, according to the embodiment,
According to the X-ray fluoroscopic image processing apparatus of the present invention, since an unsharp masking image can be obtained at high speed, an X-ray fluoroscopic image that clearly shows the fine structure that the surgeon most wants to see can be compared with the case of only the conventional integration processing. It can be obtained in the same processing time.

[Brief description of the drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

[Description of Signs] 1 Switch 2 A / D converter 3 Window processor 4 D / A converter 5 Frame memory for integrated image 6 Frame memory for blurred image 7, 8 Adder 9, 10 Multiplier 11 Subtractor 12 Memory Address controller

Claims (1)

(57) [Claims] 1. A first integration means for adding a video signal of an X-ray fluoroscopic image while matching a corresponding pixel position in a plurality of frames, and a second integration means for adding a video signal of a fluoroscopic image while shifting a corresponding pixel position. An X-ray fluoroscopic image processing apparatus comprising: integrating means; weighting means for each of the integration results; and subtraction means for subtracting both weighted integration results.