Depth-of-Field Rendering via Depth Interval Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Depth-of-field rendering algorithms are computationally expensive due to their reliance on variable-size convolutions, making them inefficient for real-time applications in graphics and image editing.

Innovation Solution

A layer-based approach is implemented, where an image is linearized by removing camera response functions, partitioned into disjointed depth intervals, and pixels are blurred separately within each interval using a disk blur with varying radii, followed by blending and re-applying camera response functions after blurring.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If variable-size convolutions are used to achieve realistic depth-of-field effects, then rendering quality is improved, but computational cost and rendering time increase significantly

Engineering Contradiction:
Improvedepth-of-field rendering qualityVSAvoidrendering speed
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The patent segments the depth map into multiple depth intervals, where each interval corresponds to a specific blur radius. This segmentation allows the algorithm to process pixels with similar depth values together, applying a single convolution operation per depth interval rather than variable-size convolutions for each pixel, thereby reducing computational complexity while maintaining rendering quality.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent changes the blur radius parameter based on depth intervals rather than computing variable blur radii for each pixel. By discretizing the continuous blur radius into a finite set of values corresponding to depth intervals, the algorithm reduces the computational burden of variable-size convolutions while preserving the depth-of-field effect.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If variable-size convolutions are applied to each pixel, then accurate depth-of-field blur is achieved, but computational complexity increases

Engineering Contradiction:
Improveblur accuracy per pixelVSAvoidalgorithm complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent divides the image processing into discrete depth intervals, where each interval is processed independently with a fixed blur radius. This segmentation simplifies the algorithm by replacing complex per-pixel variable-size convolutions with simpler fixed-size convolutions applied to segmented regions, reducing overall algorithmic complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent transforms the continuous parameter of blur radius into discrete values associated with depth intervals. This parameter discretization reduces algorithmic complexity by eliminating the need for dynamic blur radius calculation for each pixel, while still achieving accurate depth-of-field effects through the interval-based approach.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentUS9734551B1Providing depth-of-field renderings
Publication Date: 2017.08.15 GOOGLE LLC
  • US9734551B1 patent drawing
  • US9734551B1 patent drawing
  • US9734551B1 patent drawing

AI summary

Implementations generally relate to providing depth-of-field renderings. In some implementations, a method includes linearizing an image. The method further includes partitioning a depth map of the image into a plurality of depth intervals. The method further includes blurring pixels associated with each depth interval, where the pixels of each depth interval are blurred separately from the pixels of the other depth intervals. The method further includes applying at least one camera response function to the image after the pixels of the plurality of depth intervals are blurred.