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Optical Flow Back-Projection
Motion vector plays one
significant feature in moving object segmentation. However, the motion vector
in this application is required to represent the actual motion displacement,
rather than regions of visually significant similarity. In this project,
Region-based Selective Optical Flow Back-projection (RSOFB) which
back-projects optical flows in a region to restore the region’s motion vector from
gradient-based optical flows, is proposed to obtain genuine motion
displacement. The back-projection is performed based on minimizing the
projection mean square errors of the motion vector on gradient directions. As
optical flows of various magnitudes and directions provide various degrees of
reliability in the genuine motion restoration, the optical flows to be used
in the RSOFB are optimally selected based on their sensitivity to noises and
their tendency in causing motion estimation errors. In this project a
deterministic solution is also derived for performing the minimization and obtaining
the genuine motion magnitude and motion direction.
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Fall Detection
using Modular Neural Networks and Back-projected Optical Flow
This project presents a
video-based algorithm for fall detection. The algorithm is based on the
back-projected optical flow and modular neural networks. From a video
sequence, the moving object is first extracted and the pixels with high
variance of the extracted object are determined as feature points. Then the
proposed back-projected optical flow is employed to estimate the genuine
motion of these feature points. The normalized accumulated values of four
directions of the estimated motion vectors of the feature points form a
to-be-recognized feature vector. The sequence of feature vectors is fed into
a time-delay neural network modular to detect whether a falling event occurs.
The outputs of different modules, which have learned different moving
direction of the object, are fed into a committee neural network for fall
detection.
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Improving the
reliability of RFID-based Psychiatric patient tracking
This project is focusing on
promoting the reliability of psychiatric patients tracking using RFID system.
RFID has been regarded one economic approach in monitoring the psychiatric
patients. However, in order that the RFID can be commonly accepted as one of
the major methods in patient monitor, it requires both the low false alarm
rate and the low miss detection rate. In other words, the reliability of
patient tracking needs to achieve a significant high level. However, with
current RFID techniques, several reasons which could usually cause the
interference and miss detection are (1) the interferences of signals from two
locators of overlapped cover ranges and (2) the interference of signals from
close tags. All these reasons cause the high false alarm and miss detection
rates in psychiatric patients tracking using RFID.
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Using Curve
Fitting and Spectro-temporal Neural Network for Triggering Feature Analysis
and Behavior Modeling of FM Specialized Cells
In recent years, Biomedical
Informatics has become a new trend of science and technology. Biomedical
Informatics is bringing together researchers from bioinformatics, medical
informatics and computer science. The principle of this subject is using
mathematical computation, statistics and computer analysis for life sciences
research. Therefore, their application is very extensively, including genes,
medical treatment, medicine and so on.
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Tangible Photo-Realistic Virtual Museum
(2005/07/21)
We present a tangible
photo-realistic virtual museum system that couples augmented panorama and vision-based
tracking with tangible interface to achieve the real-time interaction between
the visitor and the exhibitions. This system explores how to use a physical
object named physical control cube (PCC) as a tangible embodiment of the
visitor's hand when s/he appreciates the exhibitions. This approach provides
a direct mode of browsing the museum in the cyberspace as we walk in the
museum. This research was supported in part by the National Digital Archives
Program, NSC 93-2422-H-001-0004 and 93-0201-29-戊- 3-6.2.2
from the National Science Council, Taiwan and developed in Institute of
Information Science, Academia Sinica.
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Reconstructing 3D
Model of Real Scenes from Photographs (2005/08/03)
This system automatically
extracts the 3D information and reconstructs a textured 3D model from a
sequence of images of a real scene. No prior knowledge about the scene is
needed to build the 3D models. All information such as camera pose and
orientation will be estimated through the processes. Therefore, this system
offers a high degree of flexibility when taking photographs. The only
constraint is the intrinsic camera parameters need to be obtained first.
The 3D modeling task is
decomposed into 4 successive steps. The camera intrinsic parameters are
calibrated using a calibration board first. Second, the camera pose and the
epipolar geometry between a stereoscopic image pair are estimated by the
corresponding points of this pair. Next, consecutive images of the sequence
are treated as stereo pair and the disparity maps are computed by area
matching. Finally, the dense 3D points are estimated by the linking matches
through consecutive image pairs. Then, these 3D points are visualized as a 3D
model which is also texture mapped for photo-realistic appearance. This
system has been tested on several real scenes, and some of the reconstructed
models are shown in this paper
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Vision-Based Gait
Analysis
This research provides an
approach to analyze gait. By this approach, some abnormal types of gait can
be distinguished. This research is aimed to help home-care systems and
surveillance applications.
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Modified MMSE DMC
and Error Concealment for Improving H.264 Error Resilience
(2005/08/08)
This study proposed schemes
to improve H.264 error resilience. Besides improving the original spatial and
temporal error concealment schemes adopted in H.264 test model, we use
double-motion-vector mechanism to decrease error propagation.
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A Motion Emphasized 3-D SPIHT for Visual Improved Video Coding
This research proposes to
rearrange bit rates from eye-sensitive regions which is the motion of the
video to eye-insensitive regions which is the static regions of the video, so
that eye-sensitive regions would have higher fidelity so as to obtain a
better visual condition on the whole video in low bit rate situations.
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The Integration of Physiological Signals from
Multiple Devices Plan And Home Health Care Box (2005/08/11)
In this plan we will
implement a intelligent home health care box with extensibility. The care box
has functions of collecting physiological signal and information exchange and
the ability of intelligently automatic alarm notification. Through the system
configuration, the family health care box can connect various care devices
and accept the related physiological signal of the patient. The built-in
function of physiological signal detection and alarm function can analyze the
physiological situation to judge the unusual change and other symptom
reaction. It will broadcast alarm when the unusual situation happened to
increase the immediacy of care and convenience of home care to the patient.
And through physiological signal monitoring function , the care center can
understand well the health condition and related physiology signal of the
patient.
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3-D Localization of Clustered Microcalcifications Using Cranio-Caudal and Medio-Lateral Oblique Views
This research presents a 3-D localization method to register clustered microcalcifications on mammograms from cranio-caudal (CC) and medio-lateral oblique (MLO) views. The method consists of three major components: registration of clustered microcalcifications in CC and MLO views, 3-D localization of clustered microcalcifications and 3-D visualization of clustered microcalcifications. The registration is performed based on three features, gradient, energy and local entropy codes that are independent of spatial locations of microcalcifications in two different views and are prioritized by discriminability in a binary decision tree. The 3-D localization is determined by a sequence of coordinate corrections of calcified pixels using the breast nipple as a controlling point. Finally, the 3-D visualization implements a virtual reality modeling language viewer (VRMLV) to view the exact location of the lesion as a guide for needle biopsy. In order to validate our proposed 3-D localization system, a set of breast lesions, which appear both in mammograms and in MR Images is used for experiments where the depth of clustered microcalcifications can be verified by the MR images.
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Comparative Evaluation of classifiers and Feature Selection Methods for Mass Screening in Whole Digitized Mammograms
The objective of this research is to extract the features from Digitized Mammograms block by block based on a variety of texture features, and improve Correct Classification Rate for mass screening by comparing classifiers with difference Feature Selection Methods.
Unlike traditional methods that are employed to perform detection based on gray level, this paper has adopted three groups of characteristics related to mass texture, namely, SGLD(Spatial Gray Level Dependence), TS(Texture Spectrum) and TFCM(Texture Feature Coding Method). Totally 19 texture features are offered to describe the characteristics of masses and normal textures. Next, under the testing by classifiers, three Feature Selection Methods--SBS (Sequential Backward Selection), SFS (Sequential Forward Selection) and SFSM (Sequential Floating Search Method) are used to find out suboptimal subset from 19 features in order to improve the performance of mass detection. Finally, the performances are compared when two classifiers—PNN (Probabilistic Neural Network) and SVM (Support Vector Machine) are applied--to find out the optimum correct classification rate.
The experimental images in this research are obtained from MIAS MiniMammographic Database offered by Mammographic Image Analysis Society (MIAS). The experimental data show that, the testing samples of this system can offer a 98% Detection Rate, with only 1.4% False Alarm Rate.
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Tissues Classification for Breast MRI Contrast Enhancement Using Kalman Filter-based Linear Mixing Method
Among the most recent techniques of breast examination, a great attention is being paid to breast MRIs. Since the contrast-enhanced breast MRIs acquired by traditional contrast-injection has shown to be very sensitive in the detection of breast cancer, this system adopts a spectral signature detection technology, Kalman Filter-based Linear Mixing Method (KFLM), which could successfully classify breast MRIs into four major tissues and present the classified results in high contrast tissue-separated images. A series of experiments using real MRIs and phantoms are conducted and compared to the commonly used c-means (CM) method for performance evaluation. After compare with CM algorithm and contrast-injected breast MRIs, the results showed that the high contrast images generated by spectral signature detection technologies had a superior quality.
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Using Feature Selection with Support Vector Machine in Gastric Histology Classification (2004/08/01)
This study presented a computer-aided diagnosis system using sequential forward floating selection (SFFS) with support vector machine (SVM) to assist physicians to obtain gastric histology from endoscopic images without invasive biopsy during endoscopy. At first, lots of candidate images features of endoscopic images are extracted via discrete wavelet transform, color and texture criterion in the feature extraction stage. However, lots of candidate image features cannot effectively describe histological results. Then, in the feature selection stage, SFFS is applied to select a subset of features, which performs the best classification result under SVM. In the feature classification stage, SVM can do the classification task well based on the selected image features. In order to enhance the performance of the classifier, finding proper threshold in SVM for different histological results is necessary. Based on this methodology, a new diagnosis system is implemented to provide physicians the instant gastric histology results during the endoscopy without invasive biopsy.
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