Yannick Francken

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We propose a technique for cheap and efficient acquisition of mesostructure normal maps from specularities, which only requires a simple LCD monitor and a digital camera. Coded illumination enables us to capture subtle surface details with only a handful of images. In addition, our method can deal with heterogeneous surfaces, and high albedo materials. We(More)
Developments in the consumer market have indicated that the average user of a personal computer is likely to also own a webcam. With the emergence of this new user group will come a new set of applications, which will require a user-friendly way to calibrate the position of the camera with respect to the location of the screen. This paper presents a fully(More)
In this paper we present a method for efficient calibration of a screen-camera setup, in which the camera is not directly facing the screen. A spherical mirror is used to make the screen visible to the camera. Using Gray code illumination patterns, we can uniquely identify the reflection of each screen pixel on the imaged spherical mirror. This allows us to(More)
We present a method to efficiently acquire specular mesostructure normal maps, only making use of off-the-shelf components, such as a digital still camera, an LCD screen and a linear polarizing filter. Where current methods require a specialized setup, or a considerable number of input images, we only need a cheap setup to maintain a similar level of(More)
In this paper we present a novel method for 3D structure acquisition, based on structured light. Unlike classical structured light methods, in which a static projector illuminates a scene with time-varying illumination patterns, our technique makes use of a moving projector emitting a static striped illumination pattern. This projector is translated at a(More)
We propose an efficient technique for normal map acquisition, using a cheap and easy to build setup. Our setup consists solely of off-the-shelf components, such as an LCD screen, a digital camera and a linear polarizer filter. The LCD screen is employed as a linearly polarized light source emitting gradient patterns, whereas the digital camera is used to(More)
We propose a technique for gloss and normal map acquisition of finescale specular surface details, or mesostructure. Our main goal is to provide an efficient, easily applicable, but sufficiently accurate method to acquire mesostructures. We therefore employ a setup consisting of inexpensive and accessible components, including a regular computer screen and(More)
We present a technique for retreiving the position and orientation of smartphones on an interactive surface using solely their built-in camera. Additional tracking hardware such as RFID tags or cameras therefore become redundant. A pattern is projected below each detected device, which is captured by its built-in camera. From this pattern, the smartphone(More)
We build on our previously proposed method [Francken et al. 2008], which acquires normal maps by analyzing the reflection of binary patterns (Gray codes). These patterns are successively refined in this process. The key idea in this paper, is that this refinement also allows us to measure the shininess for each spatial location, resulting in a gloss map.(More)
In this work we propose a real-time implementation for efficient extraction of multi-viewpoint silhouettes using a single camera. The method is based on our previously presented proof-of-concept shadow multiplexing method. We replace the cameras of a typical multi-camera setup with colored light sources and capture the multiplexed shadows. Because we only(More)