VOXEL LEVEL NEW INFORMATION UPDATES USING INTELLIGENT WEIGHTING

• US 20150024337A1
• Filed: 07/18/2014
• Published: 01/22/2015
• Est. Priority Date: 07/18/2013
• Status: Abandoned Application

• Current Assignee: A.Tron3D Gmbh
• Original Assignee: A.Tron3D Gmbh
• Inventors: BLASSNIG, Andreas, ANGERER, Helmut, KELZ, Engelbert, ZINNER, Christian, THIERJUNG, Stefan, NOWAK, Christoph, JESENKO, Jurgen, KOINIG, Horst
• Application Number:
  US14/334,726
• Publication Number:
  US 20150024337A1
• Time in Patent Office: Days
• US Class Current: 433/29
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61C 19/04 Measuring instruments specially adapted for dentistry A61C5/44 takes precedence; testing vitality of teeth A61B5/0534; radiation diagnosis specially adapted for dentistry A61B6/51
• CPC Class Codes: G01B 11/2513 with several lines being projected in more than one direction, e.g. grids, patterns
• CPC Class Codes: G01B 2210/52 Combining or merging partially overlapping images to an overall image
• CPC Class Codes: G06T 15/06 Ray-tracing
• CPC Class Codes: G06T 15/08 Volume rendering
• CPC Class Codes: G06T 15/205 Image-based rendering
• CPC Class Codes: G06T 17/00 Three dimensional [3D] modelling, e.g. data description of 3D objects
• CPC Class Codes: G06T 19/20 Editing of 3D images, e.g. changing shapes or colours, aligning objects or positioning parts
• CPC Class Codes: G06T 2207/10028 Range image; Depth image; 3D point clouds
• CPC Class Codes: G06T 2207/30036 Dental; Teeth
• CPC Class Codes: G06T 7/0012 Biomedical image inspection
• CPC Class Codes: G06T 7/579 from motion
• CPC Class Codes: H04N 13/167 Synchronising or controlling image signals
• CPC Class Codes: H04N 13/221 using the relative movement between cameras and objects
• CPC Class Codes: H04N 13/254 in combination with electromagnetic radiation sources for illuminating objects
• CPC Class Codes: H04N 13/275 from 3D object models, e.g. computer-generated stereoscopic image signals
• CPC Class Codes: H04N 2013/0081 Depth or disparity estimation from stereoscopic image signals
• CPC Class Codes: H04N 23/56 provided with illuminating means

Abstract

A method of integrating new information from depth maps into an existing three-dimensional representation of an object surface, the representation being a truncated signed distance function (TSDF) noted in individual voxels, the TSDF indicating, to respective coordinates within a defined volume, a distance to a next surface, includes obtaining a depth map showing the object, the depth map containing values from measurements; and integrating new information from the depth map into the existing TSDF, wherein each individual voxel affected by the depth map within the TSDF is updated and the update for each updated voxel is selected from the group of a front update if said voxel is near the outer side, a rear update if the voxel is near the inner side, and an ambiguous update, each kind of update leads to a different weighting for the updated value within the voxel.

Claims

1. A method of integrating new information containing values from depth maps into an existing three-dimensional representation of an object, said representation containing a surface being a virtual representation of the surface of said object, said surface having an inner side and an outer side and said representation being in the form of a truncated signed distance function (TSDF), that is noted in individual voxels within a voxel grid, wherein the truncated signed distance function (TSDF) indicates, to respective coordinates within a defined volume, a distance to the next surface, comprising the steps of:

obtaining a depth map of a scene showing the object or a part of the object, the depth map containing values from measurements; and

integrating new information from said depth map into the existing truncated signed distance function (TSDF),

wherein each individual voxel affected by the depth map within the TSDF is updated and wherein the update for each updated voxel is selected from the group consisting of

i) a front update if said voxel is near the outer side,

ii) a rear update if said voxel is near the inner side, and

iii) an ambiguous update, and

wherein each kind of update leads to a different weighting for the updated value within the voxel.

2. The method of claim 1, wherein the front update corresponds to surfaces represented by the depth image being oriented approximately identically to the surface within the representation and the new information approximately match the voxel value.

3. The method of claim 1, wherein the rear update corresponds to surfaces represented by the depth image being oriented oppositely to the surface within the representation.

4. The method of claim 1, wherein the ambiguous update corresponds to surfaces represented by the depth image being inclined with the surface within the representation.

5. The method of claim 1, wherein the front update gives the updated value a higher weighting relative to the value previously integrated within the voxel.

6. The method of claim 1, wherein the rear update gives to the update value a lower weighting relative to the value previously integrated within the voxel.

7. The method of claim 1, wherein the ambiguous update gives the update value a lower weighting relative to the value previously integrated within the voxel.

8. The method of claim 1, wherein the weighting over all updates is accumulated per voxel.

9. The method of claim 8, wherein,

the updated truncated signed distance function is visualized, and

the accumulated weighting is represented by different colors within the visualization of the truncated signed distance function.

10. A non-transitory computer readable medium containing computer code that when executed on a computer causes the computer to execute the method of claim 1.