Gaussian Mixture Model Hierarchy for Point Cloud Compression

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional point cloud processing techniques face challenges such as high computational power and memory requirements due to large data volumes, uneven sampling density, and unstructured data organization, making it difficult to efficiently compress and extract surface information from point cloud data for real-time applications.

Innovation Solution

A method involving the generation of a Gaussian Mixture Model (GMM) hierarchy, where point cloud data is represented using a tree structure with probabilistic occupancy maps, and the Expectation-Maximization algorithm is used to adjust parameters, allowing for efficient compression and extraction of iso-surfaces using a modified marching cubes algorithm.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional point cloud processing techniques are used, then processing can be performed on raw data points, but computational power and memory requirements become excessively high

Engineering Contradiction:
Improveprocessing accuracyVSAvoidcomputational power requirement
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent segments the point cloud data into multiple octants using an octree data structure. Each octant is processed independently, dividing the large-scale processing problem into smaller, more manageable sub-problems. This segmentation allows parallel processing and reduces the computational burden on any single processing unit while maintaining overall processing accuracy.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transforms the processing approach from operating on individual 3D points to operating on volumetric regions (octants) defined by spatial boundaries. This dimensional transformation allows the system to work with aggregated spatial data representations rather than individual points, significantly reducing computational requirements while preserving essential geometric information.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Quantity of substance

If spatial subdivision hierarchy (octree) is used to compress point cloud data, then data volume is reduced, but discretization artifacts are produced

Engineering Contradiction:
Improvedata volumeVSAvoidgeometric accuracy
Core Design Contradiction:
Quantity of substanceVSManufacturing precision

Solution Approach 1:

The patent applies partial action by selectively refining only those octants that contain geometric features above a certain threshold. Instead of uniformly processing all octants at maximum detail, the system applies varying levels of refinement based on local geometric complexity, reducing data volume while preserving important geometric features and minimizing discretization artifacts in critical areas.

Inventive Principle:
Principle #16Partial or excessive action

Solution Approach 2:

The patent dynamically adjusts refinement parameters and occupancy thresholds based on local geometric characteristics. By changing parameters such as occupancy thresholds, refinement levels, and sampling densities adaptively across different regions of the point cloud, the system optimizes the balance between compression ratio and geometric accuracy, reducing artifacts in regions where they would be most noticeable.

Inventive Principle:
Principle #35Parameter changes

3Measurement precision

If more points are stored in the point cloud, then higher fidelity representation is achieved, but memory requirements increase

Engineering Contradiction:
Improverepresentation fidelityVSAvoidmemory requirement
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent applies local quality by assigning different levels of point density and representation fidelity to different regions of the point cloud based on their geometric importance. Regions with complex geometry or high visual significance receive higher fidelity representation with more points, while simpler regions use coarser representations. This localized quality adjustment maintains overall representation fidelity while significantly reducing total memory requirements.

Inventive Principle:
Principle #3Local quality

Data Source

PatentUS10482196B2Modeling point cloud data using hierarchies of Gaussian mixture models
Publication Date: 2019.11.19 NVIDIA CORP
  • US10482196B2 patent drawing
  • US10482196B2 patent drawing
  • US10482196B2 patent drawing

AI summary

A method, computer readable medium, and system are disclosed for generating a Gaussian mixture model hierarchy. The method includes the steps of receiving point cloud data defining a plurality of points; defining a Gaussian Mixture Model (GMM) hierarchy that includes a number of mixels, each mixel encoding parameters for a probabilistic occupancy map; and adjusting the parameters for one or more probabilistic occupancy maps based on the point cloud data utilizing a number of iterations of an Expectation-Maximum (EM) algorithm.