Virtual endoscope image-generating device, method, and program

A virtual endoscope image generation method of acquiring a three-dimensional image including a large intestine region, and generating a virtual endoscope image representing an image obtained by virtually imaging the inside of the large intestine region using an endoscope based on the three-dimensional image of the large intestine region, the method comprising:

• generating the virtual endoscope image based on an opacity template in which a pixel value of the three-dimensional image is associated with an opacity, the opacity template being capable of showing both of an inner wall of the large intestine region and an inner wall of a residue region present in the large intestine region on the virtual endoscope image,
• a viewpoint set in the vicinity of a boundary between a space region and the residue region in the large intestine region,
• a set surface set at a position separated by a previously set distance in a previously set line-of-sight direction from the viewpoint, and
• a pixel value on a light beam vector beyond the set surface among pixel values of the three-dimensional image on the light beam vector extending from the viewpoint,
• wherein, in the opacity template, an opacity of a first value is assigned to voxel wall of the large intestine, an opacity of the first value is assigned to the voxel data of a boundary portion between the residue region and the inner wall of the large intestine, and an opacity of a second value is assigned to the voxel data in the space region and the voxel data in the residue region.

A non transitory computer readable recording medium having stored therein a virtual endoscope image generation program that causes a computer to function as a three-dimensional image acquisition unit that acquires a three-dimensional image including a large intestine region, and a virtual endoscope image generation unit that generates a virtual endoscope image representing an image obtained by virtually imaging the inside of the large intestine region using an endoscope based on the three-dimensional image of the lame intestine region,

• wherein the virtual endoscope image generation unit generates the virtual endoscope image based on an opacity template in which a pixel value of the three-dimensional image is associated with an opacity, the opacity template being capable of showing both of an inner wall of the lame intestine region and an inner wall of a residue region present in the large intestine region on the virtual endoscope image,
• a viewpoint set in the vicinity of a boundary between a space region and the residue region in the large intestine region,
• a set surface set at a position separated by a previously set distance in a previously set line-of-sight direction from the viewpoint, and
• a pixel value on a light beam vector beyond the set surface among pixel values of the three-dimensional image on the light beam vector extending from the viewpoint,
• wherein, in the opacity template, an opacity of a first value is assigned to voxel data of a boundary portion between a space region in the large intestine and the inner wall of the large intestine, an opacity of the first value is assigned to the voxel data of a boundary portion between the residue region and the inner wall of the large intestine, and an opacity of a second value is assigned to the voxel data in the space region and the voxel data in the residue region.