Problem & Motivation

Solution: Using a Depthmap with the
Z-Buffer Method described by Wloka u. Anderson (1995)

Estimation of Depthinformation

• Model Based Estimation
• Edge Based Estimation
• Structured Light Depthmap Usage
• Structured Light Reconstruction

Simple Approach

• detailed depth estimation per Tango depth frame
• limited depth
• visible noise
• Can be used in constrained environment
• small distance

Demo

own combination of different approaches

• RANSAC plane detection by Yang u.a. Förstner (2010)
• 3 planes in spartial octree cluster
• plane reconstruction like Trevor u.a. (2012)
• using the convex hull of supporting points

Prototype implementation

• augmenting reconstruction
• approximation of surfaces (reduces noise)
• keeps false positives
• gaps between planes
• too inaccurate for detailed reconstruction
• Can be used in rough environments

Demo

Chisel - Klingensmith u.a. (2015)

• optimized for mobile environments
• uses TSDF data structure
• saves memory because of spartial hashing
• Marching Cubes rendering
• corrects itself by Space Carving

Prototype implementation: OpenChisel

• augmenting reconstruction
• surface approximation (reduces noise)
• Space Carving is erasing false-positives
• No gaps
• too inaccurate for detailed reconstruction
• can be used in wide areas

Demo

surface approximations and noise is producing errors

Idea: filter on depth image frame buffer

• reducing noise
• closes gaps of plane reconstrcution
• isn't performant because of OpenCV
• OpenCV filter is limited to 8 Bit

demo

on GitHub

Demo

Optimizing Plane Reconstruction

introducitn features of Chisel

• Spatial Hashing
• Space Carving
• limiting the depth sensing (noise reduction)

How can planes be merged?

Optimizing Chisel

GPU Implementierung

• small voxel is increasing the level of detail
• Marching Cubes could be replaced by Raycasting

Microsoft Kinect Fusion (2015)

Questions for Guided Filter

• Some errors can be erased - some couldn't not, why?
• How to reduce depth artifacts? (8Bit - 16Bit?)

Optimization of Guided Filter

Implementation as OpenGL Fragmentshader?

Optimization of Depthinformation

Applying the filter before the integration into the reconstruction

Newcombe u.a. (2011)

alternative: Using more sophisticated Depth-Upsampling techniques

Shadow Vertex Shader Demo