Real-time lens blur effects and focus control

Abstract

(b) (c) (d) (a)Figure 1: Example images rendered in real time by our method. We achieve near-accurate depth-of-field effects, including lens aberrations (e.g., spherical aberration, (a)). The efficiency of our method makes it well-suited for artistic purposes and we support complex simulations like tilt-shift photography (b). Further, our system offers an intuitive control of depth of field and we extend the physical model (c) to achieve an expressive, yet convincing result (d) (here, the background statues stay focused). AbstractWe present a novel rendering system for defocus blur and lens effects. It supports physically-based rendering and outperforms previous approaches by involving a novel GPU-based tracing method. Our solution achieves more precision than competing real-time solutions and our results are mostly indistinguishable from offline rendering. Our method is also more general and can integrate advanced simulations, such as simple geometric lens models enabling various lens aberration effects. These latter is crucial for realism, but are often employed in artistic contexts, too. We show that available artistic lenses can be simulated by our method. In this spirit, our work introduces an intuitive control over depth-of-field effects. The physical basis is crucial as a starting point to enable new artistic renderings based on a generalized focal surface to emphasize particular elements in the scene while retaining a realistic look. Our real-time solution provides realistic, as well as plausible expressive results.

Modeling and removing spatially-varying optical blur

“…HsienChe Lee [10] models a generic optical system, however, our measurements show that there are strong dependencies on the particular lens being used. Sungkil Lee et al [11] describe optical aberrations from a rendering perspective and note that these effects are often present in real imagery. Gu et al [5] develop methods to correct dirty or partially occluded optics and Raskar et al [15] model glare in lenses.…”

Temporal light field reconstruction for rendering distribution effects

“…In addition, we explicitly deal with visibility based on the similarity of the apparent trajectories of the samples in the temporal light field. Lee et al [2010] blur the distinction between sampling and reconstruction. They accelerate defocus effects by first rasterizing the scene into a layered depth image (LDI), and then performing fast ray tracing using the LDI as a scene representation.…”

Front Matter: Volume 9023

“…Comparing with single-image blurring methods, 25,26 our light field-based analysis is good at reducing two types of boundary artifacts: the boundary discontinuity and intensity leakage artifacts. We summarize four types of boundary artifacts and analyze them separately.…”

“…Previous studies suggested that the real-time DoF effects can be obtained by applying a spatially varying blur on the color image and using the disparity value to determine the size of the blur kernel. 25,26 However, this method suffers from strong intensity leakage and boundary bleeding artifacts. Other methods such as distributed ray tracing 27 and accumulation buffer 28 give more accurate results.…”