Color Rendering via Tetrahedral Barycentric Error Diffusion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional error diffusion methods for limited palette displays, such as color electrophoretic displays, often produce severe artifacts like transient and pattern jumping, which render images unusable due to unstructured and large color palettes.
Innovation Solution
The method involves receiving input data, combining it with error data, determining the simplex enclosing the data in color space, converting to barycentric coordinates, calculating and applying error data, and projecting out-of-gamut data to ensure stable color representation by using a restricted set of primaries that form a tetrahedron, thereby avoiding artifacts.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional error diffusion methods are used for limited palette displays, then color rendering is attempted, but severe artifacts like transient and pattern jumping are produced
Solution Approach 1:
The color space is segmented into multiple tetrahedra, each associated with a specific set of four primary colors. This segmentation allows the system to divide the complex color rendering problem into smaller, manageable regions where standard error diffusion can be applied effectively without causing artifacts.
Solution Approach 2:
Different regions of the color space are assigned different sets of primary colors based on their local characteristics. Each tetrahedron represents a local region with a specific color composition, allowing the system to adapt the primary color selection to the local color requirements rather than using a fixed palette throughout.
2Adaptability or versatility
If a large and unstructured color palette is used in limited palette displays, then color variety is increased, but artifacts and instability in image rendering worsen
Solution Approach 1:
The large unstructured color palette is segmented into multiple structured tetrahedra. Each tetrahedron contains a specific set of four primary colors that are well-structured for error diffusion. This segmentation allows the system to maintain color variety while ensuring stability within each local region.
Solution Approach 2:
The system changes the parameter of primary color selection based on the location in color space. By dynamically selecting which set of four primaries to use based on the input color's position within the tetrahedral decomposition, the system adapts to maintain both color accuracy and rendering stability.
3Device complexity
If standard error diffusion algorithms are applied to unstructured palettes, then processing is simplified, but artifact generation increases
Solution Approach 1:
The color space is pre-decomposed into tetrahedra with associated primary color sets before the actual error diffusion process. This preliminary structuring allows standard error diffusion algorithms to be applied directly without modification, while the pre-established tetrahedral framework prevents artifact generation by ensuring appropriate primary color selection.
Data Source
AI summary
An image is rendered on a display having a limited number of primary colors by (104) combining input data representing the color of a pixel to be rendered with error data to form modified input data, determining in a color space the simplex (208—typically a tetrahedron) enclosing the modified input data and the primary colors associated with the simplex, converting (210) the modified image data to barycentric coordinates based upon the primary colors associated with the simplex and (212) setting output data to the primary having the largest barycentric coordinate. calculating (214) the difference between the modified input data and the output data for the pixel, thus generating error data, applying (106) this error data to at least one later-rendered pixel, and applying the output data to the display and thus rendering the image on the display. Apparatus and computer-storage media for carrying out this process are also provided.