CompAesth 09: Workshop on Computational Aesthetics

Permanent URI for this collection

https://diglib.eg.org/handle/10.2312/318

Browse

Now showing 1 - 18 of 18

Adding Lighting and Viewing Effects to Digital Images
(The Eurographics Association, 2009) Grimm, Cindy; Oliver Deussen and Peter Hall
Real paintings are not truly flat but change subtly with variations in viewing direction. The pigments and painting layers also interact with the lighting environment, producing changes that range from subtle to quite dramatic. These effects are lacking in digital images. This paper describes a system that allows an artist to introduce, and control, a variety of lighting and viewing effects, such as specular reflection and refraction, through the use of additional images.
Aesthetic Appraisal of Art - from Eye Movements to Computers
(The Eurographics Association, 2009) Wallraven, Christian; Cunningham, Douglas W.; Rigau, Jaume; Feixas, Miquel; Sbert, Mateu; Oliver Deussen and Peter Hall
By looking at a work of art, an observer enters into a dialogue. In this work, we attempt to analyze this dialogue with both behavioral and computational tools. In two experiments, observers were asked to look at a large number of paintings from different art periods and to rate their visual complexity, or their aesthetic appeal. During these two tasks, their eye movements were recorded. The complexity and aesthetic ratings show clear preferences for certain artistic styles and were based on both low-level and high-level criteria. Eye movements reveal the time course of the aesthetic dialogue as observers try to interpret and understand the painting. Computational analyses of both the ratings (using measures derived from information theory) and the eye tracking data (using two models of saliency) showed that our computational tools are already able to explain some properties of this dialogue.
Aesthetic Placement of Points Using Generalized Lloyd Relaxation
(The Eurographics Association, 2009) Deussen, Oliver; Oliver Deussen and Peter Hall
In this paper we describe a computational method for producing aesthetically pleasing distributions of disks on a canvas. The positions of the disks are initially given at random and are moved into interesting configurations by means of a local optimization routine. The configurations are computed by a Voronoi-cell based optimization algorithm (Lloyd's relaxation method). We extend this method in a way that not only evenly spaced but also clustered point sets can be produced. This is done by inverting the iterative step of the optimization algorithm. We define an energy term and show that for a certain amount of energy interesting configurations appear. This is evaluated in a small user study.
ARTcams: Attributed Rational Tensor Cameras
(The Eurographics Association, 2009) Li, Chuan; Hall, Peter; Willis, Philip; Oliver Deussen and Peter Hall
Non-linear camera models are playing an increasingly important role in computer graphics, especially in image based rendering and non-photorealistic rendering. We introduce ARTcams as simple non-linear cameras, which are unique in combining both geometric projection and non-geometric attributes such as colour into a single model. The geometric component of an ARTcam subsumes many contemporary non-linear cameras, including General Linear Cameras, push-broom cameras, and X-slit cameras. The colour component generalises compositing operations. ARTcams, though, by combining geometry and other attributes generalise yet further. ARTcams can be thought of as lenses (or mirrors) that can reproduce a wide variety of real effects, including aerial perspective, depth of field, as well as both geometric and chromatic aberrations. They can be calibrated for both geometry and colour against real optical devices. It is possible to specify ARTcams by drawing alone. This paper explains and demonstrates the ARTcam model.
Automated Landscape Painting in the Style of Bob Ross
(The Eurographics Association, 2009) Kalaidjian, Alex; Kaplan, Craig S.; Mann, Stephen; Oliver Deussen and Peter Hall
We present a system that can generate convincing synthetic landscape paintings with no user intervention whatsoever, nor any information about 3D geometry or lighting. The system is based on a direct implementation of the "wet-on-wet" oil painting technique taught by Bob Ross for many years on his show The Joy of Painting. We implement a canvas model and a set of brushes that correspond to the canvas and brushes that Bob Ross used on his show. We then compose brush strokes into landscape features that replicate his approach stroke by stroke. Finally, we develop an engine for automatic layout of these features in a painting. We demonstrate this automated system in the context of the Bob Ross painting Forest Hills.
Automatic Views of Natural Scenes
(The Eurographics Association, 2009) Bratkova, Margarita; Thompson, William B.; Shirley, Peter; Oliver Deussen and Peter Hall
Automatic generation of well-composed and purposeful images is useful in a variety of computer graphics applications. In this work, we explore a set of criteria based on utility, perception, and aesthetics applicable to natural outdoor scenes. We also propose a method that uses the criteria to produce renderings of terrain scenes automatically.
Comparing the Readability of Graph Layouts using Eyetracking and Task-oriented Analysis
(The Eurographics Association, 2009) Pohl, Mathias; Schmitt, Markus; Diehl, Stephan; Oliver Deussen and Peter Hall
In this paper we present the results of a user study comparing the readability of force-directed, orthogonal, and hierarchical graph layouts. To this end we identified prototypical tasks which are solved using visual representations of graphs. Based on the correctness of answers and the related response time we evaluated for each task which layout is better suited. In addition, we found possible explanations for these results by analyzing the eye-tracking data. Finally, we discuss some implications of our findings for algorithm designers and application developers.
Consistent Scene Illumination using a Chromatic Flash
(The Eurographics Association, 2009) Kim, Min H.; Kautz, Jan; Oliver Deussen and Peter Hall
Flash photography is commonly used in low-light conditions to prevent noise and blurring artifacts. However, flash photography commonly leads to a mismatch between scene illumination and flash illumination, due to the bluish light that flashes emit. Not only does this change the atmosphere of the original scene illumination, it also makes it difficult to perform white balancing because of the illumination differences. Professional photographers sometimes apply colored gel filters to the flashes in order to match the color temperature. While effective, this is impractical for the casual photographer. We propose a simple but powerful method to automatically match the correlated color temperature of the auxiliary flash light with that of scene illuminations allowing for well-lit photographs while maintaining the atmosphere of the scene. Our technique consists of two main components. We first estimate the correlated color temperature of the scene, e.g., during image preview. We then adjust the color temperature of the flash to the scene's correlated color temperature, which we achieve by placing a small trichromatic LCD in front of the flash. We demonstrate the effectiveness of this approach with a variety of examples.
Contrast Brushes: Interactive Image Enhancement by Direct Manipulation
(The Eurographics Association, 2009) Dodgson, Neil A.; Grundland, Mark; Vohra, Rahul; Oliver Deussen and Peter Hall
We implement contrast brushes, an interactive method for directly brushing contrast adjustments onto an image. The adjustments are performed by a histogram warping approach that implements tone mapping using piecewisedefined, continuously differentiable, monotonic splines. This allows the independent specification of tone changes and contrast adjustments without causing halo or contouring artifacts, while still endowing contrast brushes with intelligible parameters that render their effects predictable for the user. A user study demonstrates that contrast brushes can prove more effective than Adobe Photoshop's interactive contrast enhancement tools.
Controlling Color Regions of Leaves with Painting Techniques for Landscape Arts
(The Eurographics Association, 2009) Akagi, Yasuhiro; Kataama, Mitsunori; Kitajima, Katsuhiro; Oliver Deussen and Peter Hall
In this paper, we propose a non-photorealistic rendering (NPR) framework for creating landscape art in traditional animation. The proposed method is based on painting techniques for landscape arts, which enables a user to reproduce features of the target work of art and its style. Landscape (background) arts is generally used in animation productions. One image of landscape art and multiple layers of moving characters compose a scene. Landscape art is one of most important factors for making the impression of an animation. We propose a NPR technique that reproduces painting techniques for landscape arts such as leaf painting based on just a few colors, shading to produce a spherical effect. The technique developed by the authors generates dynamic landscape art having a swaying motion in the wind by applying the animation generation technique for swaying trees to it.
CubeCam: A Screen-space Camera Manipulation Tool
(The Eurographics Association, 2009) Sudarsanam, Nisha; Grimm, Cindy; Singh, Karan; Oliver Deussen and Peter Hall
We present CubeCam, an image-space camera manipulation widget that uses a projected cube to both visualize the relationship of the camera to the scene and as an interaction tool to change that camera. The cube geometry reflects the use of perspective lines by artists in order to establish the scene projection. We allow the user to interactively change the camera by changing the cube's projection in the image plane. We incorporate pie menus, ghosting, and a crossing-style interface to reduce mouse movement and make it simpler for novice users to learn and experiment with the interface. Finally, we provide a novel method for visualizing camera bookmarks.
Distinctive Parameters of Expressive Motion
(The Eurographics Association, 2009) Bartram, Lyn; Nakatani, Ai; Oliver Deussen and Peter Hall
Recent work has shown the potential of basic perceptual properties of motion for notification, association and visual search. Yet evidence from fields as diverse as perceptual science, social psychology and the performing arts suggest that motion has much richer communication potential in its interpretative scope. A long history of research and practice in the affective properties of motion has resulted in a bewildering plethora of potentially rich communicative attributes. What remains to be established is how and whether these perceptual effects and impressions can be computationally manipulated in a display environment as variables of affective communication. In this paper we explore attributes of expressive motion and report initial results from a study in which we explored which attributes might be most important in distinguishing motions meant to convey emotion.
Generalized Descriptions for the Procedural Modeling of Ancient East Asian Buildings
(The Eurographics Association, 2009) Teoh, Soon Tee; Oliver Deussen and Peter Hall
Many ancient East Asian buildings are noted for their immense beauty and intricate design. We introduce a graphics modeling library based on a generalized procedural description we formulated to describe East Asian architecture. By setting the desired parameters, a user can create a building in any of the many different styles, such as Chinese, Japanese or Korean. Different building types, such as palace halls, commoner houses, temples, pagodas, pavilions, ceremonial gates and fences, are described by our modeling system. This large range of traditional East Asian styles and structures is significantly more than those supported by existing systems.
Image Statistics for Clustering Paintings According to their Visual Appearance
(The Eurographics Association, 2009) Spehr, Marcel; Wallraven, Christian; Fleming, Roland W.; Oliver Deussen and Peter Hall
Untrained observers readily cluster paintings from different art periods into distinct groups according to their overall visual appearance or 'look' [WCF08]. These clusters are typically influenced by both the content of the paintings (e.g. portrait, landscape, still-life, etc.), and stylistic considerations (e.g. the 'flat' appearance of Gothic paintings, or the distinctive use of colour in Fauve works). Here we aim to identify a set of image measurements that can capture this 'naïve visual impression of art', and use these features to automatically cluster a database of images of paintings into appearance-based groups, much like an untrained observer. We combine a wide range of features from simple colour statistics, through mid-level spatial features to high-level properties, such as the output of face-detection algorithms, which are intended to correlate with semantic content. Together these features yield clusters of images that look similar to one another despite differences in historical period and content. In addition, we tested the performance of the feature library in several classification tasks yielding good results. Our work could be applied as a curatorial or research aid, and also provides insight into the image attributes that untrained subjects may attend to when judging works of art.
Magnetic Curves: Curvature-Controlled Aesthetic Curves Using Magnetic Fields
(The Eurographics Association, 2009) Xu, Ling; Mould, David; Oliver Deussen and Peter Hall
We describe 'magnetic curves', a particle-tracing method that creates curves with constantly changing curvature. It is well known that charged particles in a constant magnetic field trace out circular or helical trajectories. Motivated by John Ruskin's advice to use variation in curvature to achieve aesthetic curves, we propose to continuously change the charge on a simulated particle so that it can trace out a complex curve with continuously varying curvature. We show some examples of abstract figures created by this method and also show how some stylized representational forms, including fire, hair, and trees, can be drawn with magnetic curves.
Movie Posters from Video by Example
(The Eurographics Association, 2009) Brooks, Stephen; Oliver Deussen and Peter Hall
We present the first method for the generation of posters directly from video, borrowing the layout and composition from existing poster exemplars as a guide. Our system analyzes a given poster by determining face locations and poses, detecting the title and computing an analysis of the remaining background image. Processing of the video proceeds by locating major cast members and a suitable background frame. A new poster is then seamlessly constructed from scratch with faces, title and background appropriately sized and positioned as in the example. This work has broad application and potential for widespread use given the increasing importance of Creative Commons amateur film making, as well as internet and personal video.
A Painterly Rendering Based on Stroke Profile and Database
(The Eurographics Association, 2009) Seo, SangHyun; Park, JinWan; Yoon, KyungHyun; Oliver Deussen and Peter Hall
We present a method for producing painting-like images composed of predefined brush strokes. Our proposed method is based on image retrieval method and uses a stroke database. The stroke database consists of transformed copies of the several brush stroke profiles which are obtained from an actual brush stroke. An input image can be reordered in a painterly manner by combination of brush strokes retrieved from the database. Our method is able to produce a painting with diverse media by changing the type of database, such as oil and pastel. In this process, we present a search algorithm to select an appropriate brush stroke from database and an assessment algorithm to judge whether to draw the retrieved brush stroke on the canvas or not. We also introduce a efficient brush stroke model and way of achieving the appearance of thick paint without physical simulation.
Style Nodes and Repolygonization for Hierarchical Tree-Based Implicit Surface Modelling
(The Eurographics Association, 2009) Jepp, Pauline; Araujo, Bruno; Jorge, Joaquim; Wyvill, Brian; Sousa, Mario Costa; Oliver Deussen and Peter Hall
In this paper we present an extension to a hierarchical tree based implicit surface modelling system that includes interactively controlling style and appearance, and also creating a more accurate curvature based polygonal approximation. Multiple styles can be layered and applied to objects so that they are guided by local geometry although not strictly bound by it. To achieve this a new node, the Style Unary Node, is added to the ShapeShop BlobTree, which creates a style blending region inspired by primitive field blending. As visualization of implicit surfaces in interactive environments is often based on polygonization a more accurate curvature based polygonisation algorithm is also presented.

Browse

Browsing CompAesth 09: Workshop on Computational Aesthetics by Title

Results Per Page

Sort Options