Image processing apparatus and imaging processing method

1. An image processing apparatus comprising:

a volume data generator configured to generate volume data which relates to an object;

a volume renderer configured to project the volume data to a first plane with respect to a viewpoint of a user, and to acquire a projection image,

wherein the volume renderer is further configured to determine a value of each pixel of the projection image based on respective distances between first surface points and second surface points, the first surface points being points that are shown from the viewpoint of the user from among points which constitute a surface of the volume data, and the second surface points being points that are shown from a position of virtual light from among the points which constitute the surface of the volume data.

2. The image processing apparatus according to claim 1 , wherein the volume renderer comprises:

a first voxel detector configured to detect a plurality of first voxels through which a first ray which is irradiated toward a pixel of the first plane from the viewpoint of the user has propagated, from among voxels which constitute the volume data;

a color value determiner configured to determine respective color values of the first voxels based on a two-dimensional (2D) color map; and

an attenuator configured to apply an attenuation coefficient based on the respective distances between the first surface points and the second surface points to at least one color value of the color values of the first voxels.

3. The image processing apparatus according to claim 2 , wherein

the 2D color map is generated based on a color gamut of a sample image of the object,

lightness values of the color gamut of the sample image are mapped to vary along a horizontal axis of the 2D color map;

chroma values and hue values of the color gamut of the sample image are mapped to vary along a vertical axis of the 2D color map; and

the mapped lightness values, the mapped chroma values, and the mapped hue values are respectively converted into Red (R), Green (G), and Blue (B) values, and then stored.

4. The image processing apparatus according to claim 3 , wherein the color value determiner is further configured to search for coordinate values which correspond to intensity values of the first voxels in the horizontal axis of the 2D color map, to search for coordinate values which correspond to depth values of the first voxels in the vertical axis of the 2D color map, and to determine R, G, and B values which correspond to the found coordinate values as respective color values of the first voxels.

5. The image processing apparatus according to claim 2 , wherein the color values of the first voxels include Red (R), Green (G), and Blue (B) values, and the attenuator is further configured to apply different respective attenuation coefficients to each of the R, G, and B values.

6. The image processing apparatus according to claim 2 , wherein the volume renderer further comprises an image producer configured to determine a value which is obtained by accumulating color values to which the attenuation coefficient has been applied from among the color values of the first voxels and color values to which the attenuation coefficient has not been applied from among the color values of the first voxels, as a color value of the pixel of the first plane.

7. The image processing apparatus according to claim 1 , wherein the volume renderer comprises an image producer configured to determine a value which is obtained by accumulating opacity values of the first voxels, as an opacity value of the pixel of the first plane.

8. The image processing apparatus according to claim 1 , further comprising a display device configured to display the projection image.

9. An image processing method comprising:

generating volume data which relates to an object; and

projecting the volume data to a first plane with respect to a viewpoint of a user, and acquiring a projection image,

wherein the acquiring the projection image comprises determining a value of each pixel of the projection image based on respective distances between first surface points and second surface points, the first surface points being points that are shown from the viewpoint of the user from among points which constitute a surface of the volume data, the second surface points being points that are shown from a position of virtual light from among the points which constitute the surface of the volume data.

10. The image processing method according to claim 9 , wherein the acquiring the projection image comprises:

detecting first voxels through which a first ray which is irradiated toward a pixel of the first plane from the viewpoint of the user has propagated, from among voxels which constitute the volume data;

determining respective color values of the first voxels based on a two-dimensional (2D) color map; and

applying an attenuation coefficient based on the respective distances between the first surface points and the second surface points to at least one color value of the color values of the first voxels.

11. The image processing method according to claim 10 , wherein

the 2D color map is generated based on a color gamut of a sample image of the object,

lightness values of the color gamut of the sample image are mapped to vary along a horizontal axis of the 2D color map;

chroma values and hue values of the color gamut of the sample image are mapped to vary along a vertical axis of the 2D color map; and

the mapped lightness values, the mapped chroma values, and the mapped hue values are respectively converted into Red (R), Green (G), and Blue (B) values, and then stored.

12. The image processing method according to claim 11 , wherein the determining the color values of the first voxels comprises:

searching for coordinate values which correspond to intensity values of the first voxels in the horizontal axis of the 2D color map;

searching for coordinate values which correspond to depth values of the first voxels in the vertical axis of the 2D color map; and

determining R, G, and B values which correspond to the found coordinate values as respective color values of the first voxels.

13. The image processing method according to claim 10 , wherein the color values of the first voxels include Red (R), Green (G), and Blue (B) values, and the applying the attenuation coefficient comprises applying different respective attenuation coefficients to each of the R, G, and B values.

14. The image processing method according to claim 10 , further comprising determining a value which is obtained by accumulating color values to which the attenuation coefficient has been applied from among the color values of the first voxels and color values to which the attenuation coefficient has not been applied from among the color values of the first voxels, as a color value of the pixel of the first plane.

15. The image processing method according to claim 9 , further comprising determining a value which is obtained by accumulating opacity values of the first voxels, as an opacity value of the pixel of the first plane.