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This paper introduces a framework for long-distance face recognition using both dense- and sparse-stereo reconstruction. Two methods to determine correspondences of the stereo pair are used in this paper: (a) dense global stereo-matching using maximum-a-posteriori Markov Random Fields (MAP-MRF) algorithms and (b) Active Appearance Model (AAM) fitting of both images of the stereo pair and using the...
Bone mineral density (BMD) measurements and fracture analysis of the spine bones are restricted to the Vertebral bodies (VBs). In this paper, we present a novel and fast 3D segmentation framework of VBs in clinical CT images using the graph cuts method. The Matched filter is employed to detect the VB region automatically. In the graph cuts method, a VB (object) and surrounding organs (background)...
Face detection and Facial feature extraction are considered among the most studied topics in the field of biometrics. In real-world uncontrolled scenarios, high rate of false alarm is still a major problem. This paper presents a solution to reduce false alarm rate resulting from any generic face detector, through a fast post-processing algorithm based on utilizing a probabilistic framework for facial...
Face detection has been one of the most studied topics in the biometrics literature. A critical factor in the face detection process is the complexity of the setup used to acquire the images. The face detection might be considered a solved problem in easy setups but for outdoor setups with unconstrained illumination and background conditions the problem is still hard. In this paper we propose using...
In this paper, we propose a front-end framework for 3D human face reconstruction and recognition at a distance. A stereo acquisition system is built and deployed to capture stereo pairs of subjects at different distances. Three main issues are addressed to achieve accurate face reconstruction, which leads to good recognition; Different illumination conditions between the stereo pair due to larger...
Through depth perception, humans have the ability to determine distances based on a single 2D image projected on their retina, where shape-from-shading (SFS) provides a mean to mimic such a phenomenon. The goal of this paper is to recover 3D facial shape from a single image of unknown general illumination, while relaxing the non-realistic assumption of Lambert Ian reflectance. Prior shape, albedo...
Surface irradiance signals are turned into outgoing radiance through the surface reflectance function, which can be significantly perturbed by the illumination conditions. Due to their low-frequency nature, irradiance signals can be represented using low-order basis functions, where spherical harmonics (SH) have been extensively used to provide such basis. When capturing image irradiance from a single...
Face and eye detection algorithms are deployed in a wide variety of applications. Unfortunately, there has been no quantitative comparison of how these detectors perform under difficult circumstances. We created a dataset of low light and long distance images which possess some of the problems encountered by face and eye detectors solving real world problems. The dataset we created is composed of...
A surface reflectance function represents the process of turning irradiance signals into outgoing radiance. Irradiance signals can be represented using low-order basis functions due to their low-frequency nature. Spherical harmonics (SH) have been used to provide such basis. However the incident light at any surface point is defined on the upper hemisphere; full spherical representation is not needed...
A surface reflectance function represents the process of turning irradiance signals into outgoing radiance. Irradiance signals can be represented using low-order basis functions due to their low-frequency nature. Spherical harmonics (SH) have been used to provide such basis. However the incident light at any surface point is defined on the upper hemisphere, full spherical representation is not needed...
Spherical harmonics (SH) has been an attractive fit for illumination modeling in shape recovery after the conclusion drawn by Basri and Jacobs [1]. The main challenge is the computation of the spherical harmonics projection (SHP) images to be robust against imaging conditions other than illumination. Occlusions due to wearing apparel and makeup, or even incompliance to the requirement of the statistical...
In this paper, we propose a new 3D framework to identify and segment VBs and TBs in clinical computed tomography (CT) images without any user intervention. The Matched filter is employed to detect the VB region automatically on axial axis. To identify the VB on coronal and sagittal axis, we use a new developed approach based on 4 points automatically placed on cortical shell. To segment the identified...
Bone mineral density (BMD) measurements and fracture analysis of the spine bones are restricted to the Vertebral bodies (VBs), especially the trabecular bones (TBs). In this paper, we propose a novel, fast, and robust 3D framework to segment VBs and trabecular bones in clinical computed tomography (CT) images without any user intervention. The Matched filter is employed to detect the VB region automatically...
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