JPS6368140A - Image processor - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Objective of the Invention] (Industrial Application Field) The present invention is based on three-dimensional image information obtained by, for example, an X-ray CT device or an MRI device. The present invention relates to an image processing device that obtains images.

(Prior art) Conventionally, for example, X-ray CT using this type of image processing device has been used.
In the apparatus, etc., the position of the X-ray source 20 is fixed as shown in FIG. 10, and a bed (not shown) on which the subject P is placed is moved to collect data at each predetermined position. This is called a scanogram. A fluoroscopic image was created using this method.

However, the above method has the following drawbacks. That is, (1) In the above scanogram, the position of the illustrated X-ray B, 20 is uniquely determined mechanically, and a perspective image cannot be obtained from any direction. That is, in the figure, only a perspective image in a direction parallel to the body axis direction of the subject P can be obtained.

■In the area of interest, for example, if the remover is hidden behind the bone, etc.
In the above-mentioned scanogram image, it is not possible to see or clearly recognize the city or shape.

(Problems to be Solved by the Invention) As mentioned above, in the conventional image processing apparatus, the position of the X-ray source is mechanically and uniquely determined, making it impossible to obtain a perspective image from any direction. Can not.

■For example, if organs in the area of interest are hidden behind bones, etc.
In the above scanogram image, there is no image or the shape etc. cannot be clearly recognized.

Broadly speaking, they have the following problems.

Therefore, an object of the present invention is to provide an image processing device that solves each of the above-mentioned problems.

[Structure of the Invention] (Means for Solving the Problems) The structure of the present invention for solving each of the above problems includes a storage unit that stores three-dimensional image data, and a three-dimensional image data stored in the storage unit. a display unit that displays an image based on the image data;
A viewpoint δ2 fixed means for setting a viewpoint from an arbitrary direction of the three-dimensional image displayed on the display section, a reading means for reading out image data in each line of sight direction of this viewpoint, and each reading means read out by the reading means. and a calculation means for calculating an integral value of image data on a line of sight, and is characterized in that a perspective image from the viewpoint is (q) based on the integral value on each line of sight obtained by the calculation means.

(Function) The function of the present invention having the above configuration is to set a viewpoint from an arbitrary direction of the three-dimensional image stored in the storage unit and displayed on the display unit, and to set a perspective image from this viewpoint by 1q. There is.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIG. 1, the image processing device includes a CPU 1 that controls the rest of the device, a keyboard 2 that inputs various information,
A trackball 6 serving as a viewpoint setting means for determining the viewpoint and line of sight direction δ with respect to a 3D image displayed on a display unit, which will be described later, and a storage unit that stores 3D image data input from an image input device (not shown). A magnetic disk 4, a memory 3 consisting of a RAM, for example, that temporarily stores the image data stored on the magnetic disk 4, and an image based on the image data stored on the magnetic disk 4 or the memory 3. For example, a CRT5 display unit that displays
It consists of

The CPU 1, which is the control means, has the following functions.

(2) A function to display and control the image data stored in the memory 3 or the magnetic disk 4 on the CRT 5 as a display section.

■ Cursor mark displayed on the CRT 5, which is a display unit, based on information input from a trackball 6 (described later), which is a viewpoint setting means. For example, move the cursor mark 7 as shown in FIG. This cursor mark means the viewpoint and its line of sight.

■ Read and integrate the corresponding image data, for example, gradation information, on each line of sight of the viewpoint, and based on this integral value, the C
Displays a corresponding fluoroscopic image on the RT5, that is, functions as a calculation means.

Broadly speaking, they include the functions listed above.

As mentioned above, the viewpoint setting means 6 uses an input device commonly called a trackball. This trackball allows a cursor mark displayed on the CRT 5 to be arbitrarily moved and set by rotating a spherical rolling element in the directions indicated by arrows A to C in FIG.

That is, when the rolling element 10 is rotated in the direction of the arrow claw, the cursor mark displayed on the CRT 5 is moved at a predetermined ratio in one of the directions of the arrow e shown in FIG. When the cursor mark is rotated in the direction B, the cursor mark moves in either direction of the arrow f shown in the figure.

When the rolling element 5 is rotated in the direction of arrow C, the direction or angle of the cursor changes accordingly.

In this way, the viewpoint and the direction of the line of sight are set. It should be noted that what is indicated by P in the figure is, for example, three-dimensional image data of the subject, which is stored in advance in the storage section.

Once the viewpoint and direction of line of sight are set as described above,
Next, a radial range with that viewpoint as the apex (see Figure 5)
Select whether to obtain an integral value of 1q or a perspective image that includes the viewpoint and is perpendicular to the direction of the line of sight (see Fig. 4). This selection can be made by pressing a selection button 6a or 6b provided on the trackball 6. In this way, a perspective image can be obtained from any arbitrary viewpoint. Further, 6C in the figure is a button for displaying the cursor mark on the CRT 5. When this button 6C is pressed, a cursor mark is displayed on the CRT 5, and when it is pressed again, it is erased.

In this way, the present invention is different from conventional devices in that it is possible to create a perspective image from any direction based on three-dimensional image data stored in the storage section. Therefore, the part desired to be displayed as a perspective image can be displayed from any direction. For this reason, if, for example, a bone exists on the viewpoint side of a region from which a fluoroscopic image is to be obtained, the fluoroscopic image can be obtained by 1q while avoiding the region where the bone is present.

In other words, it is possible to eliminate the influence on the fluoroscopic image of the bone. In this way, effects such as improved diagnostic efficiency and more accurate fluoroscopic images can be obtained.

The specific principle of creating a perspective image based on the above operations will be described below. In this case, if there is a large uneven interval between the three-dimensional image data, that is, the tomographic data consisting of a plurality of pieces, for example, interpolation is performed.

After setting the viewpoint and line of sight as explained in FIG. 3 above and selecting one of the perspective images described above, the sixth
An image as shown in Figure (a) is displayed. In addition, the same figure (a
) shows the perspective image shown in FIG. 5 above.

In the figure, Q indicates the viewpoint, and the arrow indicates the line of sight. Also, 1 in the figure
In this embodiment, W shown in FIG. 3C is a preset value. Here, point of view Q is shown in the same figure (C
), consider points spaced apart by z and n from the reference end, respectively. In other words, it is point Q shown in Figure 6 (a). Image data on the line of sight from this viewpoint Q, that is,
) As shown in (), from the image data of the imperial palace layer surface that is necessarily stored, the image data corresponding to the line of sight (indicated by the dotted line in the figure) is read at predetermined intervals and integrated, and the perspective image at that position is obtained. . In this way, this viewpoint Q is moved within the range of (XW) to obtain a desired perspective image.

Next, in the case of the perspective image shown in FIG. 4, FIG.
), (b), a perspective image obtained from the viewpoint Q at a predetermined angle (in this example, a preset angle) is obtained in substantially the same manner as described in FIGS. 6 (a> to (C) above). A fluoroscopic image is set at 1q.In this case, unlike the above embodiment, a fluoroscopic image is obtained by reading and integrating grayscale information from image data of multiple sections (planes or tomographic planes), so Interpolation is enabled.

Next, the principle of IFing an arbitrary perspective image as described above will be explained.

As shown in FIG. 8, coordinates are provided in advance in the three-dimensional image data, specifically in the body axis direction of the subject P mentioned above. Now, the illustrated point Q is converted from X, Y coordinates to x, y, z coordinates, and these are (a.

b, c), and the direction vector of the parallel beam path is (U
, V, W). Then, the beam path passing through the above point Q is (x-a)/u=(y-b)/v=(z-c)/w
・It is expressed as (1). At this time, if Z=Zo, then x=u(zo -c)/w+a=x o
... (2)V
=V(ZO-c)/w+b"y o =
(3) Xo and Vo are determined by the above equations (1) to (3), and image data corresponding to (Xo, yo, Zo) is determined. The value of point Q can be determined by moving ZO determined in this way within a certain range at appropriate intervals and integrating the image data. That is, by moving this point Q within the perspective image creation range, a perspective image can be created from the desired viewpoint. In addition, one point (phase of the parallel beam and radial beam) is the direction vector of the beam path (U,
V, W).

It should be noted that the present invention is not limited to the above-mentioned embodiment, but can be modified and implemented within the scope of the gist.

For example, as shown in FIG. 9, any region of the transparent image 11 displayed on the CRT 5, that is, the region of interest 1j! (shown with diagonal lines in the figure), for example, on the CRT5 at cursor line 12.13.
A partial perspective image may be obtained by displaying these two cursor lines and integrating an arbitrary integration interval, that is, an arbitrary integration interval, within a region surrounded by these two cursor lines and the erroneous beam path (not shown at 14). By determining the integral value partially in this manner, it is possible to eliminate the influence of the bone shown by 15 in the figure on the region to be obtained on the creation of a perspective image. Therefore, it is possible to obtain a clear and clear perspective image of the target area.

Roughly speaking, when this device is combined with, for example, radiotherapy equipment, the effectiveness of the planned plan can be confirmed by creating and displaying a fluoroscopic image under the same conditions as the plan. In addition, by superimposing the dose distribution and checking how much of the target irradiation area the irradiation range covers while changing the irradiation conditions, it is possible to create an optimal treatment plan.

[Effects of the Invention] As described in detail above, according to the present invention, a desired perspective image can be obtained from any direction, and a clear and clear perspective image can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the configuration of the image processing device of the present invention, FIG. 2 is an external perspective view of a trackball, and FIG. 3 is a perspective view illustrating the relationship between a three-dimensional image displayed on the display unit and a cursor mark. , FIG. 4 and FIG. 8 are explanatory diagrams illustrating the principle of creating a perspective image, FIG. 8 is a perspective view showing the general principle of creating a perspective image, FIG. 9 is an explanatory diagram showing a modification of the present invention, and FIG. The figure is an explanatory diagram of a conventional method of converting a perspective image by 1q. DESCRIPTION OF SYMBOLS 1... Reading means, calculation means, 4... Storage part, 5... Display part, 6... Viewpoint setting means. Agent Patent Attorney Rules
Ogo Qufu<01'>1 (b) Figure 7

Claims (2)

[Claims] (1) A storage unit that stores three-dimensional image data, a display unit that displays an image based on the three-dimensional image data stored in this storage unit, and a display unit that displays the three-dimensional image displayed on this display unit from any direction. a viewpoint setting means for setting a viewpoint; a reading means for reading out image data in each line-of-sight direction of the viewpoint;
calculation means for calculating the integral value of the image data on each line of sight read out by the reading means, and obtaining a perspective image from the viewpoint based on the integral value on each line of sight obtained by the calculation means. An image processing device characterized by: (2) The image processing apparatus according to claim 1, wherein the viewpoint setting means has a function of setting an arbitrary integral interval in the line-of-sight direction of the viewpoint.