Object recognition using shape-from-shading

This paper investigates whether surface topography information extracted from intensity images using a recently reported shape-from-shading (SFS) algorithm can be used for the purposes of 3D object recognition. We consider how curvature and shape-index information delivered by this algorithm can be used to recognize objects based on their surface topography. We explore two contrasting object recognition strategies. The first of these is based on a low-level attribute summary and uses histograms of curvature and orientation measurements. The second approach is based on the structural arrangement of constant shape-index maximal patches and their associated region attributes. We show that region curvedness and a string ordering of the regions according to size provides recognition accuracy of about 96 percent. By polling various recognition schemes. including a graph matching method. we show that a recognition rate of 98-99 percent is achievable

Analysis and approximation of some Shape-from-Shading models for non-Lambertian surfaces

The reconstruction of a 3D object or a scene is a classical inverse problem in Computer Vision. In the case of a single image this is called the Shape-from-Shading (SfS) problem and it is known to be ill-posed even in a simplified version like the vertical light source case. A huge number of works deals with the orthographic SfS problem based on the Lambertian reflectance model, the most common and simplest model which leads to an eikonal type equation when the light source is on the vertical axis. In this paper we want to study non-Lambertian models since they are more realistic and suitable whenever one has to deal with different kind of surfaces, rough or specular. We will present a unified mathematical formulation of some popular orthographic non-Lambertian models, considering vertical and oblique light directions as well as different viewer positions. These models lead to more complex stationary nonlinear partial differential equations of Hamilton-Jacobi type which can be regarded as the generalization of the classical eikonal equation corresponding to the Lambertian case. However, all the equations corresponding to the models considered here (Oren-Nayar and Phong) have a similar structure so we can look for weak solutions to this class in the viscosity solution framework. Via this unified approach, we are able to develop a semi-Lagrangian approximation scheme for the Oren-Nayar and the Phong model and to prove a general convergence result. Numerical simulations on synthetic and real images will illustrate the effectiveness of this approach and the main features of the scheme, also comparing the results with previous results in the literature.Comment: Accepted version to Journal of Mathematical Imaging and Vision, 57 page

Neural Face Editing with Intrinsic Image Disentangling

Traditional face editing methods often require a number of sophisticated and task specific algorithms to be applied one after the other --- a process that is tedious, fragile, and computationally intensive. In this paper, we propose an end-to-end generative adversarial network that infers a face-specific disentangled representation of intrinsic face properties, including shape (i.e. normals), albedo, and lighting, and an alpha matte. We show that this network can be trained on "in-the-wild" images by incorporating an in-network physically-based image formation module and appropriate loss functions. Our disentangling latent representation allows for semantically relevant edits, where one aspect of facial appearance can be manipulated while keeping orthogonal properties fixed, and we demonstrate its use for a number of facial editing applications.Comment: CVPR 2017 ora

High-Performance Integrated Window and Façade Solutions for California

The researchers developed a new generation of high-performance façade systems and supporting design and management tools to support industry in meeting California’s greenhouse gas reduction targets, reduce energy consumption, and enable an adaptable response to minimize real-time demands on the electricity grid. The project resulted in five outcomes: (1) The research team developed an R-5, 1-inch thick, triplepane, insulating glass unit with a novel low-conductance aluminum frame. This technology can help significantly reduce residential cooling and heating loads, particularly during the evening. (2) The team developed a prototype of a windowintegrated local ventilation and energy recovery device that provides clean, dry fresh air through the façade with minimal energy requirements. (3) A daylight-redirecting louver system was prototyped to redirect sunlight 15–40 feet from the window. Simulations estimated that lighting energy use could be reduced by 35–54 percent without glare. (4) A control system incorporating physics-based equations and a mathematical solver was prototyped and field tested to demonstrate feasibility. Simulations estimated that total electricity costs could be reduced by 9-28 percent on sunny summer days through adaptive control of operable shading and daylighting components and the thermostat compared to state-of-the-art automatic façade controls in commercial building perimeter zones. (5) Supporting models and tools needed by industry for technology R&D and market transformation activities were validated. Attaining California’s clean energy goals require making a fundamental shift from today’s ad-hoc assemblages of static components to turnkey, intelligent, responsive, integrated building façade systems. These systems offered significant reductions in energy use, peak demand, and operating cost in California

Recovering facial shape using a statistical model of surface normal direction

In this paper, we show how a statistical model of facial shape can be embedded within a shape-from-shading algorithm. We describe how facial shape can be captured using a statistical model of variations in surface normal direction. To construct this model, we make use of the azimuthal equidistant projection to map the distribution of surface normals from the polar representation on a unit sphere to Cartesian points on a local tangent plane. The distribution of surface normal directions is captured using the covariance matrix for the projected point positions. The eigenvectors of the covariance matrix define the modes of shape-variation in the fields of transformed surface normals. We show how this model can be trained using surface normal data acquired from range images and how to fit the model to intensity images of faces using constraints on the surface normal direction provided by Lambert's law. We demonstrate that the combination of a global statistical constraint and local irradiance constraint yields an efficient and accurate approach to facial shape recovery and is capable of recovering fine local surface details. We assess the accuracy of the technique on a variety of images with ground truth and real-world images

Experiences with and interpretation of standard test methods of building energy analysis tools

The authors separately apply ANSI/ASHRAE Standard 140-2001 to the simulation program TRNSYS, comparing not only their results but the differences in their simulation assumptions and in their interpretations of the Standard's test cases. Results of the application are presented for all three authors, showing that there is a significant amount of leeway within a complex simulation tool such asTRNSYS for users of different backgrounds to apply their own common simulating practices and still fall comfortably within the range of acceptability specified by such Standards. Included in the application results are results of sensitivity tests that demonstrate the relative importance of assumption differences

Early Yield and Economical Study of Pogostemon Cablinas Intercrop in Young Cocoa (Theobroma CacaoL.)

Pogostemon cablinis an important source of volatile oil for pharmaceutical and cosmetical products. Agronomical aspect of this commodity needs open ecosystem, but for certain level of shading, this crop may yield economically. A study to evaluate the effect of P. cablinintercropped on young cocoa farm, had been conducted during 2005, in Kaliwining Experimental Station of Indonesian Coffee and Cocoa Research Institute (ICCRI) 45 m above sea level, D climate type (Schmidt and Fergusson), and on low gley humic soil. The experiment was arranged in factorial and the field design was split plot replicated three times. The main plot was no shade tree, shade of Leucaena glauca and Areca catechuwhile the subsplots were fertilizer dose (per ha/year), i.e. (P0) without fertilizer; (P1) 140 kg Urea, 35 kg SP-36, 70 kg KCl; (P2) 280 kg Urea, 70 kg SP-36,140 kg KCl; and (P3) 560 kg Urea, 140 kg SP-36, 280 kg KCl. The result showed that P. cablin cultivation without shading gave better growth and yield than the shading treatment; meanwhile Leucaenashading showed better growth and early yield than the A. catechushading. Fertilizer rate of P1 produced highest leaf weight and oil yield, although P3 possessed the highest growth variables of plant height, stem diameter, number of leaves, leaf area and chlorophyll content. For the dry weight biomass variable, highest yield was obtained from no shade tree and P1 treatment. Using chromatography gas analysis, retention time of patchouly alcohol is 15—18 minutes, it was found that the content was influenced by shading treatment, i.e. 25.15% in monoculture, 28.73% in Leucaena and 25.21% in A. catechutreatment. For the oil viscosity variable, the monoculture treatment showed the highest value (23.21 centipoise), followed by A. catechu(11.60 centipoise) and Leucaenatreatment (8.65 centipoise). Intercropping of P. cablinwith young cacao did not show negative effect on young cacao growth. This study demonstrated that pre-cropping ofP. cablinin young cacao provided opportunity to farmers to have additional income, the benefit cost ratio (B/C) for Leucaenatreatment 1.00–1.35 depend on dose of fertilizer, while for A. catechutreatment gave no profit (B/C 0.59–1.03 depend on fertilizer dose). Meanwhile, P. cablinmonoculture cultivation gave B/C 1.44–2.71