Results 31 to 40 of about 1,123 (167)

Light invariant photometric stereo

Optics Express, 2023
An imaging setup that enables unsynchronized photometric stereo (PS) for Lambertian objects based on modulated light sources is presented. Knowing the specific frequency of the modulated light source allows to filter out any other light in the scene. This creates an image that depends only on the particular light source while ignoring the ambient light.
Yuval Braun, Hugo Guterman
openaire   +2 more sources

Photometric stereo for outdoor webcams [PDF]

2012 IEEE Conference on Computer Vision and Pattern Recognition, 2012
We present a photometric stereo technique that operates on time-lapse sequences captured by static outdoor webcams over the course of several months. Outdoor webcams produce a large set of uncontrolled images subject to varying lighting and weather conditions. We first automatically select a suitable subset of the captured frames for further processing,
Jens Ackermann, Fabian Langguth, Simon Fuhrmann, Michael Goesele   +3 more
openaire   +1 more source

ReDDLE-Net: Reflectance Decomposition for Directional Light Estimation

Photonics, 2022
The surfaces of real objects can visually appear to be glossy, matte, or anywhere in between, but essentially, they display varying degrees of diffuse and specular reflectance.
Jiangxin Yang, Binjie Ding, Zewei He, Gang Pan, Yanpeng Cao, Yanlong Cao, Qian Zheng   +6 more
doaj   +1 more source

Perspective Photometric Stereo with Shadows [PDF]

, 2013
High resolution reconstruction of 3D surfaces from images remains an active area of research since most of the methods in use are based on practical assumptions that limit their applicability. Furthermore, an additional complication in all active illumination 3D reconstruction methods is the presence of shadows, whose presence cause loss of information
Roberto Mecca, Guy Rosman, Ron Kimmel, Alfred M. Bruckstein   +3 more
openaire   +1 more source

PHOTOMETRIC STEREO ASSISTED DRAWING OF ARCHITECTURAL RELIEFS [PDF]

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2019
Geometric documentation is one of the most important parts of a documentary report. Despite the advances made in the field of line drawing of ancient relief surfaces, in most cases, human operator interaction is unavoidable.
A. Abzal, M. Saadatseresht, M. Varshosaz
doaj   +1 more source

An Adaptive Snake Based Shadow Segmentation for Robust Driver Fatigue Detection: A 3D Facial Feature Based Photometric Stereo Perspective

IEEE Access, 2023
Fatigue detection has many applications, one of them is intelligent transportation for accident prevention. It is challenging to detect driver fatigue adopting photometric stereo and 3D fatigue-related facial action unit identification.
Gulbadan Sikander, Shahzad Anwar, Ghassan Husnain, Rajermani Thinakaran, Sangsoon Lim   +4 more
doaj   +1 more source

Automated Optical Inspection System for O-Ring Based on Photometric Stereo and Machine Vision

Applied Sciences, 2021
This research developed an AOI (automated optical inspection) system for the O-Ring inspection. First, an AOI system was implemented to detect surface scratches, flow marks, non-fills, and indentations on elastomer O-Rings with high surface reflection ...
Fu-Sheng Yang, Chao-Ching Ho, Liang-Chia Chen   +2 more
doaj   +1 more source

Joint optimisation model for light source position based on a combined target [PDF]

MATEC Web of Conferences
Photometric stereo vision, as a non-contact three-dimensional imaging technology, can achieve fast and high-precision reconstruction of normal vectors and three-dimensional morphology of object surfaces by resolving the intensity changes under different ...
Kong Xiangjin, Wang Zijing, Miao Yupei, Liu Xiaoli, Yang Qingping, Tang Qijian   +5 more
doaj   +1 more source

ACCURACY OF 3D RECONSTRUCTION IN AN ILLUMINATION DOME [PDF]

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, 2016
The accuracy of 3D surface reconstruction was compared from image sets of a Metric Test Object taken in an illumination dome by two methods: photometric stereo and improved structure-from-motion (SfM), using point cloud data from a 3D colour laser ...
L. MacDonald, I. Toschi, E. Nocerino, M. Hess, F. Remondino, S. Robson   +5 more
doaj   +1 more source

A Survey of Photometric Stereo Techniques [PDF]

Foundations and Trends® in Computer Graphics and Vision, 2015
Reconstructing the shape of an object from images is an important problem in computer vision that has led to a variety of solution strategies. This survey covers photometric stereo, i.e., techniques that exploit the observed intensity variations caused by illumination changes to recover the orientation of the surface.
Jens Ackermann, Michael Goesele
openaire   +1 more source