Synthesizing Bidirectional Texture Function Data for Material Appearance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for visualizing real materials in product design require extensive and costly measurement processes to create accurate, physically plausible databases, which are time-consuming and impractical for creating a wide range of materials, especially complex ones like those with glittering or large surface structures.

Innovation Solution

A method that accesses measured appearance attributes of a reference material and a source material to generate a synthesized appearance, using a combination of densely populated and sparsely captured data to create a modified Bidirectional Texture Function (BTF) database, ensuring physical plausibility and reducing the need for individual databases, by iteratively minimizing error values and applying BTF editing operators.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a Bidirectional Texture Function (BTF) is measured for a given real material, then accurate visualization of the material under any illumination condition and viewing direction is achieved, but the measurement process requires complex equipment and is very time consuming

Engineering Contradiction:
Improveaccuracy of material appearance dataVSAvoidmeasurement time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

A comprehensive BTF database for a reference material is measured and stored in advance. This pre-measured database contains appearance data for multiple different surface structures, which can be later combined with sparse measurements of source materials to generate synthesized appearances without requiring full measurements for each new material.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The invention combines BTF data from a reference material with sparse appearance measurements from a source material to create a composite synthesized appearance. This allows the benefits of both comprehensive reference data and material-specific characteristics to be merged, achieving accurate visualization without full measurement of each individual material.

Inventive Principle:
Principle #40Composite materials

2Adaptability or versatility

If BTF databases are created for a large number of individual materials, then comprehensive material coverage is achieved, but substantial technical effort and expense are required

Engineering Contradiction:
Improverange of materials coveredVSAvoidmeasurement equipment and process complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

A single comprehensive BTF database from one reference material serves multiple purposes: it provides the structural framework for synthesizing appearances of many different source materials. This universal database eliminates the need to create separate comprehensive databases for each material type.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

Instead of measuring each source material comprehensively, the invention creates simplified copies or representations by combining sparse source material measurements with the comprehensive reference database. This copying approach maintains visual accuracy while dramatically reducing measurement requirements.

Inventive Principle:
Principle #26Copying

3Reliability

If analytical reflectance models are fitted to measured data, then physical plausibility is guaranteed to a certain degree, but manual parameter adjustment is tedious and accuracy is limited for complex materials

Engineering Contradiction:
Improvephysical plausibility of material appearanceVSAvoidspeed of material editing and creation
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The comprehensive BTF database from the reference material acts as an intermediary that bridges the gap between sparse source material measurements and physically plausible appearance synthesis. This intermediary provides the missing structural and physical information that would otherwise require complex manual parameter adjustment.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the approach from manually adjusting reflectance model parameters to automatically combining measured BTF data with sparse appearance measurements. This parameter-based combination approach maintains physical plausibility while dramatically increasing productivity for complex materials.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2833327B1Method and system for digitally generating appearance data
Publication Date: 2018.10.03 X RITE EUROPE GMBH
  • EP2833327B1 patent drawingFigure 1
  • EP2833327B1 patent drawingFigure 2
  • EP2833327B1 patent drawingFigure 3

AI summary

In a method of generating synthesized appearance property data of a simulated material a Bidirectional Texture Function BTF representing the simulated material is used. The BTF is suitable for input into a rendering engine capable of generating a visual representation of the material on a monitor. In the method a densely populated original BTF (B) of a reference material (MR) and sparse reflectance values (D) of a source material (MS) are provided. A modified BTF (B') is then built by transferring said sparse reflectance values (D) into said original BTF (B).