JP3077773B2 - 3D image display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional image display device for displaying a three-dimensional image by collecting a plurality of two-dimensional images.

[0002]

2. Description of the Related Art A three-dimensional image display device has been realized for the purpose of improving diagnosis efficiency in medical diagnosis, observing a target portion with high accuracy, and the like. This three-dimensional image display device continuously collects a plurality of two-dimensional slice images (tomographic images) S1, S2, S3,... Of a target site photographed by an ultrasonic scanner as shown in FIG. It is stored in a three-dimensional memory, and if necessary, three-dimensional image data is read from the three-dimensional memory, displayed on a display unit, and provided for diagnosis.

In such a case, to take a slice image with an ultrasonic scanner or the like, 1/20 to 1 /
A time of about / 30 (second) is required. This imaging time is a long time as compared with the time of respiration, pulsation, etc. of the subject. Further, in order to form a three-dimensional image by collecting these slice images, a large amount of slice images is required, so that it takes a considerable time to collect image data.

[0004]

As described above, in the conventional three-dimensional image display apparatus, the time required to form a slice image required to construct a three-dimensional image is longer than the time required for respiration, pulsation, and the like. Since inaccurate three-dimensional data is stored under the influence of respiration, pulsation, and the like, there is a problem in that when displaying a three-dimensional image, the image is distorted.

[0005] The present invention has been made in view of the above problems, and has as its object to provide a three-dimensional image display device capable of displaying a three-dimensional image without distortion.

[0006]

In order to achieve the above object, the present invention provides a method for continuously reproducing a two-dimensional ultrasonic image of a target site.
Tertiary display of three-dimensional ultrasound image constructed by collecting several images
The original image display device stores a plurality of ultrasonic images.
Memory and two-dimensional cross-correlation processing
Correlation processing means for calculating the amount of displacement between two-dimensional ultrasonic images
And a position between the ultrasonic images based on the displacement amount.
Correcting means for correcting the misalignment;
Three-dimensional image data based on the ultrasonic image
A three-dimensional memory for storing data .

[0007]

According to the present invention, a position shift portion of an image is obtained by calculating a two-dimensional cross-correlation function between adjacent images of a continuous two-dimensional image, and the position shift portion is corrected. This eliminates displacement between adjacent images, so that no distortion occurs when displaying a three-dimensional image.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of a three-dimensional image display device according to the present invention.
3D image data collection unit 2 and image misalignment detection unit 3
And an image displacement correcting unit 4 and a three-dimensional image forming unit 5
, A display unit 6 and a control unit 7.

The three-dimensional image data collecting section 2 continuously collects and stores a plurality of two-dimensional slice images S1, S2, S3,... Taken by an ultrasonic scanner or the like as shown in FIG. It has a three-dimensional memory, and holds three-dimensional data of a target part for displaying a three-dimensional image.

The inter-image positional deviation detecting section 3 detects whether or not there is a positional deviation between adjacent images of a continuously collected two-dimensional image. The principle of this detection will be described later. The inter-image position shift correcting unit 4 is for correcting the position shift on a two-dimensional image when a position shift is detected between images.

The three-dimensional image forming unit 5 reads out three-dimensional image data from the three-dimensional memory after the positional displacement between the images has been corrected and forms a three-dimensional image. The three-dimensional image is a CRT. It is displayed on a display unit 6 composed of a monitor or the like. The control unit 7 has a built-in CPU (Central Processing Unit) and controls the entire control operation.

Next, the principle of detecting the positional deviation between images in the positional deviation detecting unit 3 will be described. As shown in FIG. 2, two-dimensional slice images S1, S2, continuously collected
Of the S3,..., Two-dimensional cross-correlation functions CC (X,
Y) is calculated based on Equation 1.

[0014]

(Equation 1) Here, fn: n-th slice image fm: m-th slice image x, y: coordinates of the slice image X, Y: any deviation value

For example, it is assumed that the two-dimensional cross-correlation function CC of the partial area M of S1 and S2 is calculated. By calculating the two-dimensional cross-correlation function CC between adjacent two-dimensional images, a peak P is obtained on the X and Y coordinates as shown in FIG.

If there is no displacement between the regions M of the images S1 and S2, the position of the peak P appears on the center (0, 0) of the X and Y coordinates as shown in FIG. However, if a positional shift has occurred, the position of the peak P shifts from the center (0, 0) of the X and Y coordinates in a direction in which the positional shift is reflected, as shown in FIG. This is represented as a motion vector V as shown in FIG.

Therefore, by correcting the X and Y coordinates on the image only for the motion vector V, it is possible to eliminate the displacement between adjacent images. Such correction is performed under the control of the control unit 7, and is performed on the target image in the three-dimensional image data collection unit 2. Next, the operation of the present embodiment based on the above detection principle will be described.

The inter-image position shift detecting unit 3 selects S1 and S2 as adjacent images and calculates a two-dimensional cross-correlation function CC between the respective partial areas M, thereby obtaining the shift of the peak P as shown in FIG. Suppose the position has been determined. Based on this, under the control of the control unit 7, the inter-image positional deviation correcting unit 4 performs correction on the X and Y coordinates of the image so as to move the deviation of the peak P in the opposite direction.

As a result, the positional deviation of the target image in the three-dimensional image data collection unit 2 is corrected, and the three-dimensional data based on the corrected position is stored in the three-dimensional memory. The three-dimensional image forming unit 5 reads out the corrected three-dimensional image data from the three-dimensional memory, forms a three-dimensional image, and displays the three-dimensional image on the display unit 6.

According to this embodiment, even if the displacement between adjacent images occurs due to the influence of respiration, pulsation, etc.
Since this displacement is corrected, accurate three-dimensional data can be stored. Therefore, when a three-dimensional image is displayed, no distortion occurs in this image.

The method of designating a partial region M in an adjacent image and detecting a positional deviation between the regions as in this embodiment is particularly advantageous for an image having a large area. That is, in the case of a large image, the respective regions are not necessarily displaced in the same direction, and it is effective to designate the target region as a part.

Even when the entire area is targeted, the same effect can be obtained by dividing the area into, for example, six areas 6A to 6F as shown in FIG. However, due to the correction after the displacement, each region has an overlap or a space as shown by a broken line. Therefore, this problem can be solved by performing averaging processing on the overlapping portion A1 and performing interpolation processing on the empty portion A2. Alternatively, when there is little movement in the entire image, the position shift may be detected for the entire area.

[0023]

As described above, according to the present invention, the displacement of an image is obtained by calculating a two-dimensional cross-correlation function between adjacent images of a continuous two-dimensional image, and this displacement is corrected. Since a three-dimensional image is configured based on this later, a three-dimensional image without distortion can be displayed.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of a three-dimensional image display device of the present invention.

FIG. 2 is an explanatory diagram of a two-dimensional image for explaining the principle of the present invention.

FIG. 3 is an explanatory diagram of a two-dimensional cross-correlation function according to the principle of the present invention.

FIG. 4 is an explanatory diagram of a two-dimensional cross-correlation function according to the principle of the present invention.

FIG. 5 is an explanatory diagram of a motion vector according to the principle of the present invention.

FIG. 6 is a schematic diagram illustrating the operation of the embodiment of the present invention.

FIG. 7 is an explanatory diagram of a method for collecting a two-dimensional image forming a three-dimensional image.

[Explanation of symbols]

 2 3D image data collecting unit 3 Image misalignment detecting unit 4 Image misalignment correcting unit 5 3D image composing unit 6 Display unit 7 Control unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI G06T 17/00 G06F 15/66 360

Claims (2)

(57) [Claims] 1. A two-dimensional ultrasonic image of a target part is continuously obtained.
A three-dimensional ultrasound image displayed by collecting multiple images
In a three- dimensional image display device, a memory for storing a plurality of ultrasonic images and a two-dimensional
Correlation processing means for determining the amount of positional deviation between images , based on the amount of positional deviation, the position between the ultrasonic images
Correction means for correcting the displacement, and an ultrasonic image in which the displacement has been corrected by the correction means.
A three- dimensional image display device comprising a three-dimensional memory for storing three-dimensional image data based on the three-dimensional image data . 2. The three-dimensional image display device according to claim 1 , wherein said correlation processing means calculates the two-dimensional cross-correlation function using the entire region or a partial region of the target image. .