IMAGE RENDERING METHOD AND APPARATUS

• US 20180174355A1
• Filed: 12/19/2016
• Published: 06/21/2018
• Est. Priority Date: 12/19/2016
• Status: Active Grant

• Current Assignee: Canon Medical Systems Corporation (Canon Inc.)
• Original Assignee: Toshiba Medical Systems Corporation (Canon Inc.)
• Inventors: DAY, Timothy, WAHRENBERG, Magnus, REYNOLDS, Steven, CHAU, Gerald, SMOUT, Andy
• Granted Patent: US 10,467,798 B2
• Time in Patent Office: Days
• CPC Class Codes: A61B 6/032 Transmission computed tomography [CT]
• CPC Class Codes: A61B 6/037 Emission tomography
• CPC Class Codes: A61B 6/461 Displaying means of special interest
• CPC Class Codes: A61B 6/466 adapted to display 3D data
• CPC Class Codes: A61B 8/461 Displaying means of special interest
• CPC Class Codes: A61B 8/466 adapted to display 3D data 3D imaging and stereoscopic displays in devices for short-range imaging with acoustic waves G01S15/8993 and G01S7/52068, respectively; 3D image rendering G06T15/00; manipulating 3D models for computer graphics G06T19/00
• CPC Class Codes: A61B 8/467 characterised by special input means
• CPC Class Codes: G01N 29/0609 Display arrangements, e.g. colour displays indicating or recording in connection with measuring in general G01D
• CPC Class Codes: G01S 15/8993 Three dimensional imaging systems
• CPC Class Codes: G01S 7/52071 Multicolour displays; using colour coding; Optimising colour or information content in displays, e.g. parametric imaging
• CPC Class Codes: G06T 15/08 Volume rendering
• CPC Class Codes: G06T 2210/41 Medical
• CPC Class Codes: G09G 2340/06 Colour space transformation
• CPC Class Codes: G09G 2380/08 Biomedical applications
• CPC Class Codes: G09G 5/04 using circuits for interfacing with colour displays
• CPC Class Codes: G09G 5/10 Intensity circuits
• CPC Class Codes: G09G 5/40 characterised by the way in which both a pattern determined by character code and another pattern are displayed simultaneously, or either pattern is displayed selectively, e.g. with character code memory and APA, i.e. all-points-addressable, memory

Abstract

An image rendering apparatus comprises processing circuitry configured to: obtain a volumetric medical imaging data set representative of a region of a material; associate an extinction color with the material; obtain from a user a color value; determine a modified extinction color for the material based on the color value obtained from the user; and render a global illumination image from the volumetric medical imaging data set using the modified extinction color.

Claims

1. An image rendering apparatus comprising processing circuitry configured to:

obtain a volumetric medical imaging data set representative of a region of a material;

associate an extinction color with the material;

obtain from a user a color value;

determine a modified extinction color for the material based on the color value obtained from the user; and

render a global illumination image from the volumetric medical imaging data set using the modified extinction color.

2. An apparatus according to claim 1, wherein the processing circuitry is further configured to:

determine based on the extinction color a chromatic attenuation profile representative of color value as a function of intensity and as a function of depth in the material.

3. An apparatus according to claim 2, wherein the determining of the chromatic attenuation profile comprises, for each of a plurality of depths in the material, determining a color value at that depth based on an accumulated opacity of the material at that depth.

4. An apparatus according to claim 2, wherein:

the processing circuitry is further configured to display the chromatic attenuation profile to a user;

the obtaining from the user of the color value comprises obtaining from the user a modified color value for a point on the chromatic attenuation profile at a selected intensity and depth; and

the determining of the modified extinction color is based on the modified color value at the selected intensity.

5. An apparatus according to claim 3, wherein the processing circuitry is further configured to determine a modified chromatic attenuation profile based on the modified extinction color and to display the modified chromatic attenuation profile to the user.

6. An apparatus according to claim 2, wherein:

the processing circuitry is further configured to indicate based on the chromatic attenuation profile a characteristic depth in the material;

the obtaining from a user of the color value comprises obtaining from the user a modified color value for the characteristic depth; and

the determining of the modified extinction color is based on the modified color value at the characteristic depth.

7. An apparatus according to claim 5, wherein the characteristic depth comprises a depth at which a pre-determined proportion of light entering the material is attenuated by the material.

8. An apparatus according to claim 5, wherein the determining of the modified extinction color based on the modified color value comprises using the equation:

c′

=c*̂

(log(1−

a)/log(1−

k))

where c′

is the modified extinction color, c* is the modified color value, a is opacity and k is accumulated opacity at the characteristic depth.

9. An apparatus according to claim 5, wherein the determining of the modified extinction color comprises determining a modified extinction color for a first intensity value, and interpolating or extrapolating the modified extinction color at the first intensity value to obtain a modified extinction color for one or more further intensity values.

10. An apparatus according to claim 1, wherein the processing circuitry is further configured to render using the extinction color or modified extinction color a global illumination image of a substantially homogeneous object formed of the material, the substantially homogeneous object having a predetermined shape and a constant intensity value.

11. An apparatus according to claim 10, wherein the predetermined shape comprises at least one of a sphere, a first tubular structure, at least one further tubular structure having a different thickness, orientation and/or angle of lighting than the first tubular structure.

12. An apparatus according to claim 10, wherein the processing circuitry is further configured to receive user input indicative of the predetermined shape and/or the constant intensity value.

13. An apparatus according to claim 1, wherein the processing circuitry is configured to display to the user at least one color value derived from the extinction color;

wherein the obtaining of the color value from the user comprises obtaining an adjustment of the or each displayed color value; and

wherein the determining of the modified extinction color is based on the at least one color value and the adjustment.

14. An apparatus according to claim 13, wherein the adjustment of the or each color value received from the user comprises an offset.

15. An apparatus according to claim 14, wherein the processing circuitry is further configured to apply the offset to at least one further color value to obtain at least one further extinction color.

16. An apparatus according to claim 1, wherein the processing circuitry is further configured to display to a user a user interface comprising at least one of:

a chromatic attenuation profile, an image of a substantially homogeneous object, an extinction color modulation plot.

17. An apparatus according to claim 16, wherein the processing circuitry is further configured to obtain via the user interface a user input comprising at least one of:

the color value, a predetermined shape, a constant intensity value.

18. An apparatus according to claim 1, wherein the associating of the extinction color with the material comprises, for at least one intensity value of the material, obtaining a color and opacity for the material at the intensity value, and determining an extinction color at the intensity value based on the color and opacity, wherein the determining of the extinction color comprises using the equation:

Extinction value_c=1−

(1−

a)̂

(1−

c)

where c is each of red, green and blue and a is opacity.

19. An apparatus according to claim 1, wherein the associating of the extinction color with the material comprises using an extinction color transfer function for the material, the extinction color transfer function relating extinction color to intensity value.

20. An image rendering method comprising:

obtaining a volumetric medical imaging data set representative of a region of a material;

associating an extinction color with the material;

obtaining from a user a color value;

determining a modified extinction color for the material based on the color value obtained from the user; and

rendering a global illumination image from the volumetric medical imaging data set using the extinction color.