JPS63213091A - Depth map preparing device - Google Patents

Abstract

PURPOSE:To shorten time required for preparing depth map by dividing the three dimensional image data of a voxel structure into the plural blocks of the voxel structure, obtaining a partial depth map every block with parallel processing of each block and unifying them one depth map. CONSTITUTION:The three dimensional image data of the voxel structure is divided into the plural blocks of the voxel structure, that means partial data 2-n, by a data division means 1 and transmitted to a partial depth map prepar ing means 3-n. By the partial depth map preparing means 3-n, the partial depth map of each block is produced with the parallel processing and stored in a partial depth map memory 4-n. The data stored in the plural partial depth map memory 4-n is read out by a partial depth map unifying means 5 and the read out data is unified to one depth map. Then the depth map is stored in an unified depth map memory 6.

Description

Detailed Description of the Invention [Object and Target of the Invention] (Industrial Application Field) The present invention relates to a depth map used when creating a pseudo three-dimensional image from image data having a voxel structure. ) for creating a depth map.

(Prior art) A pseudo three-dimensional image is created from image data with a voxel structure, such as a series of CT images, and is displayed for diagnosis. It is created by first obtaining a depth map (also referred to as 7-buffer) in a desired line of sight direction from the image data of the structure, and executing grayscale value processing based on this depth map.

Normally, the line of sight direction when creating a pseudo three-dimensional image can be changed in any direction by operator operation.
The above depth map is created each time the line of sight direction is changed.

Depth maps can be created using a general-purpose computer, but it generally takes several tens of minutes of processing time because it must be determined for all voxels whether or not the target data exists along the viewing direction. Requires. Therefore, in order to shorten this processing time, a dedicated single processor has been used to create depth maps.

However, even if a dedicated single processor is used, the current situation is that it takes several seconds of processing time to create a depth map, and real-time processing is not possible.

(Problems to be Solved by the Invention) As described above, there is a problem in that it takes time to create a depth map.

SUMMARY OF THE INVENTION The present invention aims to eliminate the above-mentioned drawbacks and to provide a depth map creation device that enables high-speed creation of depth maps.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides data dividing means for dividing three-dimensional image data having a voxel structure into a plurality of blocks having a voxel structure, and a plurality of data dividing means arranged corresponding to the number of divided blocks. a partial depth map creation means for calculating a partial depth map for each block by parallel processing of each divided data, and a partial depth map integration means for integrating the created partial depth maps into a single depth map. and depth map creation control means for controlling the operations of the partial depth map creation means and the partial depth map integration means.

(Function) As shown in FIG. 2, the three-dimensional image data 20 having a voxel structure is divided by the data dividing means into a plurality of blocks 20-1 to 20-n having a voxel structure, which are used to create the partial depth map. sent to means. Then, by this partial depth map creation means, a partial depth map 21 is created for each block 20-1 to 20-n.
-1 to 21-n are created, and these partial depth maps 21-1 to 21-n are integrated into one depth map 22 by the partial depth map integrating means.

In this way, multiple partial depth maps are obtained by dividing the 3D image data and processing them in parallel.
By integrating these, it is possible to quickly create depth maps.

(Example) An embodiment of the present invention will be described below.

FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention. As shown in the figure, this depth map creation device has an entire three-dimensional memory 8. Data division means 1゜partial (par
tial) Three-dimensional memory 2-1゜2-2.2-3.・・・
., 2-n (n is a positive integer).

Partial depth map creation means 3-1.3-2゜3-
3. ..., 3-n, partial depth map memory 4
-1.4-2.4-3. ..., 4-n, partial depth map integration means 5. It has an integrated depth map memory 6 and depth map creation means 7.

The data dividing means 1 divides the three-dimensional image data (for example, a series of CT image data) sent from the overall three-dimensional memory 8 into a plurality of blocks having a voxel structure, and the divided data is arranged in a subsequent stage. Each block is sent to a plurality of partial three-dimensional memories 2-1 to 2-n. This partial three-dimensional memory 2-1
2-n to 2-n respectively store the divided data from the data dividing means 1, and the stored contents are stored in the partial depth map creating means 3-1 to 3-n arranged at the subsequent stage.
n, respectively.

These partial depth map creation means 3-1 to 3-n
As will be detailed later, a partial depth map is created for each divided block. Here, the partial depth map means a depth map for each block divided by the data dividing means 1, and the finally obtained depth map (integrated depth map to be described later)
It is distinguished from

The partial depth maps created by the partial depth map creation means 3-1 to 3-n are sent to the partial depth map integration means 5 via the partial depth map memories 4-1 to 4-n arranged at the subsequent stage. It has become so.

This partial depth map integrating means 5 integrates the partial depth maps taken in through the partial depth map memories 4-1 to 4-n into one depth map, and the integrated depth map data obtained thereby. (Z value) is sent to an external device via an integrated depth map memory 6 arranged at a subsequent stage. Examples of external devices include devices that perform grayscale value processing based on a depth map to generate pseudo three-dimensional display data.

The depth map creation control means 7 controls the operations of the partial depth map creation means 3-1 to 3-n and the partial depth map integration means 5. Specifically, the depth map creation control means 7 controls the operations of the partial depth map creation means 3-1 to 3-n and the partial depth map integration means 5. Given U, V.

By coordinate transformation of W (coordinates indicating the three-dimensional viewpoint position), the start coordinates (BX, BV, BZ) of the partial three-dimensional memories 2-1 to 2-n, the partial three-dimensional memories 2-1 to 2 −n, the distance after viewpoint conversion of the entire three-dimensional memory 8, and the X direction.

The displacements dx, west y, dz in the X direction and Z direction are determined and sent to the partial depth map creation means 3-1 to 3-n, and the center position of each partial depth map is calculated, and this is Depth map integration means 5
It is designed to be sent to

Here, the details of the functions of the partial depth map creation means 3-1 to 3-n and the partial depth map integration means 50 will be explained.

Each of the partial depth map creation means 3-1 to 3-n uses the start coordinates (Bx, By, Bz) sent from the depth map creation control means 7, the partial three-dimensional memories 2-1 to 2-n, and the entire three-dimensional memory. Distance after viewpoint conversion of memory 8 and displacement dx in the X direction, X direction, and Z direction
, ay, and az for reading partial three-dimensional image data.

Generate y, Z addresses. And this x, y.

Each partial depth map creation means 3-1 to 3-n takes in the image data in the corresponding partial three-dimensional memories 2-1 to 2-n according to the Z address, and then performs the predetermined data in the same way as normal depth map creation. A partial depth map is created by calculating the distance to the target object data by comparison with the set threshold value (threshold processing).

In addition, in the threshold processing described above, a portion where target object data does not exist is filled with a predetermined special code.

The above functions are performed by each partial depth map creation means 3-
It is realized by individual processors every 1 to 3-n.

Further, the integration process by the partial depth map integration means 5 calculates the position of each partial depth map on the integrated depth map based on the center coordinate value of each partial depth map sent from the depth map creation means 7. This is performed by two-dimensional processing based on this position information. That is, as shown in FIG. 2, since each partial depth map 21-1 to 21-n overlaps on the integrated depth map 22, the partial depth map integrating means 5 can detect the target object from the viewpoint at the same coordinates. The one with the shortest distance to the partial depth map, that is, the one with the smallest Z value of the partial depth map, is selected and used as the Z value of the integrated depth map. Since this integration process is a two-dimensional process, it can be performed at high speed. still,
In this integration process, the part where the above special code exists is ignored because it does not require processing.

Next, the operation of the above configuration will be explained.

Three-dimensional image data transferred from a host computer (not shown) (voxel structure > 20, the entire three-dimensional memory 8
The data is taken into the data dividing means 1 via the data dividing means 1, and is divided into a plurality of blocks 20-1 to 20-n having a voxel structure as shown in FIG. 3, and divided data 20-1 to 20-n, The data is written into the corresponding partial three-dimensional memories 2-1 to 2-n.

On the other hand, when the three-dimensional viewpoint position coordinates U, V, W are input to the depth map creation control means 7 via a console (not shown), the depth map creation control means 7 inputs the viewpoint position coordinates (U, V, W). The starting coordinates (Bx
, BY , BZ >, Partial three-dimensional memory 2
-1 to 2-n, the distance after viewpoint conversion of the entire three-dimensional memory 8, and the X direction.

Then, it is sent to the partial depth map creation means 3-1 to 3-n. Then, the partial depth map creation means 3-1 to 3-n generate x, y, z addresses for reading partial three-dimensional image data based on the information from the partial depth map creation control means 7, and according to these addresses, The partial three-dimensional memory 2-1
Read the memory contents of 2-n. When creating a partial depth map using this readout data, the entire voxel (three-dimensional image before division) of each divided voxel is
The starting position for creating a partial depth map is determined by considering the position at . That is, - voxels 2C) -, ffi divided from the entire voxel 20 shown in FIG.
When paying attention to , a partial depth map is created at a position whose coordinates have been transformed as shown in FIG. 3(b).

Figure (C) is a vector representation of the coordinate transformation of the voxel 201 in Figure (d), where C is the coordinate origin of the entire three-dimensional memory 8, and B is the coordinate origin of the partial three-dimensional memory 2-1.
The coordinate origins of 2-n are respectively represented.

Partial depth map creation in each partial depth map creation means 3-1 to 3-n is performed individually and in parallel, and the created partial depth maps are respectively stored in partial depth map memories 4-1 to ff14-n. written.

Then, when the X and y coordinate values of the center of each partial depth map calculated by the depth map creation control means 7 are input to the partial depth map creation means 5,
As shown in FIG. 2, this partial depth map integrating means 5 determines the position of each partial depth map 21-1 to ff121-n on the integrated depth map 22 based on the above x and y coordinate values, and Based on this, the respective partial depth maps 21 to 21-n are integrated.

This integration process is performed using the integrated depth map 2 as described above.
Each partial depth map 21-1 to 21- on 2
This is performed by selecting the value with the shortest distance from the viewpoint to the target object using two-dimensional processing based on the position information of n. Then, the Z value obtained through such processing is written into the integrated depth map memory 6, and a desired depth map is formed within the integrated depth map 6. This depth map in the memory 6 is a depth map at the three-dimensional viewpoint position (U, V, W) previously given by the operator, and this depth map information is used to generate pseudo three-dimensional image display data by grayscale value processing. It will be served.

In this way, in the device of this embodiment, the data dividing means 1
The 3D image data is divided into two parts and each divided data (partial 3D image data) is stored in the partial 3D memory 2.
-1 to 2-n are processed in parallel to obtain a plurality of partial depth maps, and the partial depth map integrating means 5 integrates them to obtain a depth map at a desired viewpoint position. Depth maps can be created quickly. Therefore, it is extremely effective in generating and displaying pseudo three-dimensional image data.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above-described embodiment, and that various modifications can be made.

[Effects of the Invention] As described in detail above, according to the present invention, it is possible to provide a depth map creation device that enables high-speed creation of depth maps.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an apparatus according to an embodiment of the present invention, FIG. 2 is an explanatory diagram of the principle of the invention, FIG. 3 is an explanatory diagram of division processing in the apparatus of this embodiment, and FIG. 4(a). (b) and (C) are explanatory diagrams of coordinate transformation in the device of this embodiment. DESCRIPTION OF SYMBOLS 1... Data division means, 3-1 to 3-n... Partial depth map creation means, 5... Partial depth map integration means, 7... Depth map creation control means.

Claims (1)

[Claims] In a depth map creation device that takes in three-dimensional image data with a voxel structure and creates a depth map in a desired line of sight direction, the data dividing means divides the three-dimensional image data into a plurality of blocks with a voxel structure; A partial depth map creation means that calculates a partial depth map for each block by parallel processing of multiple pieces of data arranged correspondingly and divided, and a partial depth map that integrates the created partial depth maps into a single depth map. A depth map creation device comprising: an integrating means; and a depth map creation control means for controlling operations of the partial depth map creating means and the partial depth map integrating means.