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Analysis of photometric factors based on photometric linearization
Journal of the Optical Society of America A, 2007We propose a method for analyzing photometric factors, such as diffuse reflection, specular reflection, attached shadow, and cast shadow. For analyzing real images, we utilize the photometric linearization method, which was originally proposed for image synthesis.
Yasunori Ishii +2 more
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A Benchmark Dataset and Evaluation for Non-Lambertian and Uncalibrated Photometric Stereo
IEEE Transactions on Pattern Analysis and Machine Intelligence, 2019Classic photometric stereo is often extended to deal with real-world materials and work with unknown lighting conditions for practicability. To quantitatively evaluate non-Lambertian and uncalibrated photometric stereo, a photometric stereo image dataset
Boxin Shi +5 more
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GAIA Photometric System: Simulation of Photometric Observations
Astrophysics and Space Science, 2002We present a software package developed for modelling of the GAIA photometric observations. The modelling procedure is very flexible and fully controlled via the parameter file. Therefore, configuration of the GAIA telescopes and photometric systems, as well as the object samples under investigation, can be adjusted easily.
Vladas Vansevičius +2 more
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EKLT: Asynchronous Photometric Feature Tracking Using Events and Frames
International Journal of Computer Vision, 2018We present EKLT, a feature tracking method that leverages the complementarity of event cameras and standard cameras to track visual features with high temporal resolution. Event cameras are novel sensors that output pixel-level brightness changes, called
Daniel Gehrig +3 more
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PHOTOMETRIC AND IMAGING PERFORMANCE [PDF]
EAS Publications Series, 2002 Three topics within GAIA photometry have been selected for discussion here. (1) The sampling scheme of the CCDs has been tuned to serve the various purposes: detection of stars, astrometry, broad- and medium-band photometry, and imaging of a small area around each detected star, but the tuning may not yet be optimal.
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Photometric Concepts and Magnitudes [PDF]
, 1987 Most astronomical observations utilize electromagnetic radiation in one way or another. We can obtain information on the physical nature of a radiation source by studying the energy distribution of its radiation. We shall now introduce some basic concepts characterizing electromagnetic radiation.
Pekka Kröger +4 more
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Estimating High-Resolution Surface Normals via Low-Resolution Photometric Stereo Images
IEEE transactions on circuits and systems for video technology (Print)Acquiring high-resolution 3D surface structures is a crucial task in computer vision as it provides more detailed surface textures and clearer structures. Photometric stereo can measure per-pixel surface normals of a 3D object using various shading cues.
Yakun Ju +5 more
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PS-FCN: A Flexible Learning Framework for Photometric Stereo
European Conference on Computer Vision, 2018This paper addresses the problem of photometric stereo for non-Lambertian surfaces. Existing approaches often adopt simplified reflectance models to make the problem more tractable, but this greatly hinders their applications on real-world objects.
Guanying Chen +2 more
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CNN-PS: CNN-based Photometric Stereo for General Non-Convex Surfaces
European Conference on Computer Vision, 2018Most conventional photometric stereo algorithms inversely solve a BRDF-based image formation model. However, the actual imaging process is often far more complex due to the global light transport on the non-convex surfaces.
Satoshi Ikehata
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The Photometric Sensibility of the Eye and the Precision of Photometric Observations
Journal of the Optical Society of America, 1931In this paper data are presented to show that for maximum photometric sensibility the brightness of the photometric field should be adjusted so that a brightness level of from 20 to 30 millilamberts is secured. At this brightness the difference fraction ΔB/B has a value of 1.37 percent.
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