In computer graphics, easy-to-use tools for configuring lighting for 3D scenes are required by us... more In computer graphics, easy-to-use tools for configuring lighting for 3D scenes are required by users. Following a perception-based lighting design framework, which models image quality using cognitively inspired objective functions, we present a new approach to lighting design which both: (1) allows the declarative specification of lighting; and (2) uses target scenes and images to facilitate intuitive and natural interactive control of the scene lighting. The LightOPex system enables users to select the desired lighting for a scene using exemplars in the form of 3D scenes and 2D images and uses the perceptual properties of these exemplars as target values in an initial optimization step.
Lighting design in computer graphics is essentially not a random process but one driven by both a... more Lighting design in computer graphics is essentially not a random process but one driven by both a technical and aesthetic appreciation of lighting. In some applications, the result of the lighting design process is a 2D image derived by rendering a 3D scene. Users with limited understandings of manipulation of lighting parameters may have difficulties in properly modifying the lighting parameters in order to achieve desired lighting effects. We present and demonstrate an approach to lighting design in applications where the expected result of the lighting design process is a 2D image. In this approach, the lighting-by-example method using perception-based objective function is used in combination with an interactive interface in order to optimize lighting parameters for an object or a group of objects individually, and the visual results of these separate processes are combined (utilizing 3D depth information) in the seamless generation of a final 2D image.
Declarative approaches to lighting design model image quality using an objective function that ca... more Declarative approaches to lighting design model image quality using an objective function that captures the desired visual properties of an object or scene. The value of the objective function is optimized for a particular camera configuration through the manipulation of the lighting parameters of a scene. We review the notion of declarative lighting design, and introduce LightOp, a tool by which the design of objective functions (the components and settings) and the application of different optimization techniques can be explored. We show how LightOp can be used to explore declarative lighting design through the realization of a number of extensions to existing approaches, including the application and evaluation of stochastic optimization; the use of backlighting to maximize edge enhancement; contrast modeling; and the use of a perceptually uniform color space.
Automatic lighting design aims to provide users with semi-automated approaches, and easy-to-use t... more Automatic lighting design aims to provide users with semi-automated approaches, and easy-to-use tools, to configure lighting for 3D scenes. We present LightOpex the first fully automatic example-based local illumination lighting design system. Utilizing a wavelet-based lighting design framework, by which image quality is modeled using a cognitively inspired objective function, this approach to lighting design both: (1) allows the declarative specification of lighting; and (2) facilitates intuitive and natural specification of scene lighting. LightOpex enables users to select the desired lighting for a scene using exemplar 2D images and uses the spatial distribution of the luminance in these images as the target values of an optimization step. We demonstrate the utility of LightOpex through a range of examples, and conduct a preliminary investigation of the performance of a number of different of optimization schemes.
In computer graphics, easy-to-use tools for configuring lighting for 3D scenes are required by us... more In computer graphics, easy-to-use tools for configuring lighting for 3D scenes are required by users. Following a perception-based lighting design framework, which models image quality using cognitively inspired objective functions, we present a new approach to lighting design which both: (1) allows the declarative specification of lighting; and (2) uses target scenes and images to facilitate intuitive and natural interactive control of the scene lighting. The LightOPex system enables users to select the desired lighting for a scene using exemplars in the form of 3D scenes and 2D images and uses the perceptual properties of these exemplars as target values in an initial optimization step.
Lighting design in computer graphics is essentially not a random process but one driven by both a... more Lighting design in computer graphics is essentially not a random process but one driven by both a technical and aesthetic appreciation of lighting. In some applications, the result of the lighting design process is a 2D image derived by rendering a 3D scene. Users with limited understandings of manipulation of lighting parameters may have difficulties in properly modifying the lighting parameters in order to achieve desired lighting effects. We present and demonstrate an approach to lighting design in applications where the expected result of the lighting design process is a 2D image. In this approach, the lighting-by-example method using perception-based objective function is used in combination with an interactive interface in order to optimize lighting parameters for an object or a group of objects individually, and the visual results of these separate processes are combined (utilizing 3D depth information) in the seamless generation of a final 2D image.
Declarative approaches to lighting design model image quality using an objective function that ca... more Declarative approaches to lighting design model image quality using an objective function that captures the desired visual properties of an object or scene. The value of the objective function is optimized for a particular camera configuration through the manipulation of the lighting parameters of a scene. We review the notion of declarative lighting design, and introduce LightOp, a tool by which the design of objective functions (the components and settings) and the application of different optimization techniques can be explored. We show how LightOp can be used to explore declarative lighting design through the realization of a number of extensions to existing approaches, including the application and evaluation of stochastic optimization; the use of backlighting to maximize edge enhancement; contrast modeling; and the use of a perceptually uniform color space.
Automatic lighting design aims to provide users with semi-automated approaches, and easy-to-use t... more Automatic lighting design aims to provide users with semi-automated approaches, and easy-to-use tools, to configure lighting for 3D scenes. We present LightOpex the first fully automatic example-based local illumination lighting design system. Utilizing a wavelet-based lighting design framework, by which image quality is modeled using a cognitively inspired objective function, this approach to lighting design both: (1) allows the declarative specification of lighting; and (2) facilitates intuitive and natural specification of scene lighting. LightOpex enables users to select the desired lighting for a scene using exemplar 2D images and uses the spatial distribution of the luminance in these images as the target values of an optimization step. We demonstrate the utility of LightOpex through a range of examples, and conduct a preliminary investigation of the performance of a number of different of optimization schemes.
Uploads
Papers by Hai Nam Ha