Adaptive Stroke Thickening for Graphics Objects

Solution Overview

Problem

Conventional stroke thickening techniques in computer graphics often cause fill objects with thin strokes to fade out or disappear, especially when the outline color is similar to the background color, leading to degraded image quality and content distortion.

Innovation Solution

A method and device for adaptive stroke thickening that identifies fill objects by comparing stroke, fill, and background colors, selecting an adapted color different from the background, and strengthening the stroke using this color to prevent content loss and distortion, while maintaining image quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Illumination intensity

If conventional stroke thickening techniques are applied to fill objects, then the outline visibility is improved, but the fill object fades out or disappears when the outline color is similar to the background color

Engineering Contradiction:

Improveoutline visibilityVSAvoidfill object visibility

Core Design Contradiction:

Illumination intensityVSLoss of information

Solution Approach 1:

The patent applies different color selection strategies to different regions (stroke areas vs fill areas) based on their local characteristics. The system analyzes the background color adjacent to each region and selects appropriate colors locally - using stroke color for thickening where it maintains visibility, and fill color where the stroke color would blend with the background, thus preserving fill object visibility while improving outline visibility.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent dynamically changes colors based on the background context. It compares the stroke color with the background color and selectively replaces stroke color with fill color in regions where the stroke would be invisible against the background. This color adaptation ensures that the thickened outline remains visible while preventing fill object disappearance.

Inventive Principle:

Principle #32Color changes

2Manufacturing precision

If stroke thickening is applied to improve image quality, then the outline becomes more prominent, but the fill color gets replaced by the outline color causing content distortion

Engineering Contradiction:

Improveimage qualityVSAvoidfill object appearance

Core Design Contradiction:

Manufacturing precisionVSStability of the object's composition

Solution Approach 1:

The patent applies different color selection strategies to different regions (stroke areas vs fill areas) based on their local characteristics. The system analyzes the background color adjacent to each region and selects appropriate colors locally - using stroke color for thickening where it maintains visibility, and fill color where the stroke color would blend with the background, thus preserving fill object visibility while improving outline visibility.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent performs preliminary analysis of the graphics object structure, identifying stroke regions and fill regions before applying the thickening operation. By pre-determining which areas should receive stroke color thickening and which should receive fill color thickening, the system prevents fill color replacement and maintains the original fill object appearance while still achieving the desired outline prominence.

Inventive Principle:

Principle #10Preliminary action

3Length of stationary object

If region growing algorithms are used for stroke thickening, then the outline thickness is increased, but thin fill regions overlap with the thickened outline causing content loss

Engineering Contradiction:

Improvestroke thicknessVSAvoidfill region content

Core Design Contradiction:

Length of stationary objectVSLoss of substance

Solution Approach 1:

The patent performs preliminary analysis of the graphics object structure, identifying stroke regions and fill regions before applying the thickening operation. By pre-determining which areas should receive stroke color thickening and which should receive fill color thickening, the system prevents fill color replacement and maintains the original fill object appearance while still achieving the desired outline prominence.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent dynamically changes colors based on the background context. It compares the stroke color with the background color and selectively replaces stroke color with fill color in regions where the stroke would be invisible against the background. This color adaptation ensures that the thickened outline remains visible while preventing fill object disappearance.

Inventive Principle:

Principle #32Color changes

Data Source

PatentUS9858694B1Methods and systems for adaptive stroke thickening of graphics objects

Publication Date: 2018.01.02 XEROX CORP

AI summary

Methods and devices to improve the quality of graphics objects based on adaptive stroke thickening are disclosed. The method includes receiving a graphics object having a stroke, where the stroke defines a fill region. The received graphics object is identified as a fill object based on the stroke including a first cell of a stroke color being different from a fill color of a second cell associated with the fill region. The stroke color and the fill color are compared with a background color of a third cell associated with a background according to a predefined condition, where the first cell, the second cell, and the third cell are linearly adjacent to each other. Based on the comparison, an adapted color being different from the background color of the third cell is selected to adaptively strengthen the first cell, which is associated with the stroke, away from the fill region.