Vector Interpolator for De-interlacing Using Local Edge Count Heuristic

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Interlaced video displays often introduce artifacts like 'jaggies' and line flicker when converting interlaced signals to progressive formats, as existing de-interlacers rely on vertical interpolation, which fails to accurately represent slanted features and does not effectively reduce line flicker.

Innovation Solution

A vector interpolator that determines a similarity measure for pixels within a predetermined area, selects an interpolation angle, and applies interpolated luminance values along this angle to reduce artifacts, using 3D adaptive de-interlacing to manage motion and enhance visual clarity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If vertical interpolation is used to double lines in de-interlacing, then the conversion from interlaced to progressive format is achieved, but 'jaggies' and steps appear in slanted features

Engineering Contradiction:
Improvede-interlacing conversionVSAvoidvisual accuracy of slanted features
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The patent applies different interpolation methods to different regions of the image based on edge detection. Areas with edges are processed using directional interpolation along edge vectors, while smooth regions use conventional vertical interpolation. This local differentiation resolves the contradiction by adapting the interpolation quality to local image characteristics, reducing jaggies in edge regions without compromising overall conversion efficiency.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent dynamically adjusts the interpolation approach based on detected motion and edge information. The system switches between temporal de-interlacing (for stationary regions) and spatial de-interlacing with directional interpolation (for moving regions with edges). This dynamic adaptation allows the system to maintain high visual accuracy where needed while preserving conversion productivity throughout the entire frame.

Inventive Principle:
Principle #15Dynamics

2Device complexity

If simple vertical scaling is used for line doubling, then the de-interlacing process is simplified, but line flicker is not reduced

Engineering Contradiction:
Improvede-interlacing processVSAvoidline flicker
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The patent incorporates feedback mechanisms through motion detection and edge analysis that continuously monitor the image content. Based on this feedback, the system dynamically selects between temporal and spatial de-interlacing methods, and adjusts interpolation directions to counteract line flicker. This feedback-driven approach eliminates line flicker while maintaining reasonable process complexity through intelligent method selection.

Inventive Principle:
Principle #23Feedback

3Manufacturing precision

If directional interpolation is applied to reduce jaggies, then visual clarity of slanted features is improved, but computational complexity increases

Engineering Contradiction:
Improvevisual clarityVSAvoidcomputational requirements
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies computationally intensive directional interpolation only to regions containing edges and slanted features, while using simpler vertical interpolation for smooth regions. This local quality approach concentrates computational resources where they are most needed for visual clarity, reducing overall computational complexity compared to applying complex interpolation to the entire image.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent uses partial directional interpolation by first detecting edges and then applying complex interpolation only to areas adjacent to detected edges. This partial action strategy reduces computational requirements compared to full-image directional interpolation while still achieving significant visual clarity improvements in the critical regions where jaggies occur.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentUS8306365B1Local edge count heuristic for vector interpolator
Publication Date: 2012.11.06 SYNAPTICS INC
  • US8306365B1 patent drawing
  • US8306365B1 patent drawing
  • US8306365B1 patent drawing

AI summary

A vector interpolator optimizes the conversion of an interlaced signal to a non-interlaced signal. The vector interpolator improves the visual clarity of slanted features in a displayed image by adjusting the luminance value of each pixel such that the appearance of “steps” or “jaggies” in the features is reduced. For each pixel, the vector interpolator determines a similarity measure for the pixels within a predetermined area around the pixel. From the similarity measure, an angle for interpolation is selected. The luminance value is then interpolated along the selected vector corresponding to the angle and applied to the pixel. One or more ambiguity measures such as a local edge count ambiguity measure may also be computed to indicate the reliability of the computed luminance value.