Adult bone diseases, especially osteoporosis leads to increased risk of fracture which associated... more Adult bone diseases, especially osteoporosis leads to increased risk of fracture which associated with substantial morbidity, mortality and financial cost. Clinically osteoporosis is defined as low bone mineral density. However, increasing the evidence suggests that the micro architectural quality of Trabecular Bone (TB) is more determinant of bone strength and fracture risk. Here, we present a new robust algorithm for computing TB thickness and marrow spacing at a low resolution. The star line tracking algorithm that effectively deals with partial voluming effects in vivo imaging with voxel size comparable with thickness. Also the method avoids the problem of digitization associated with conventional algorithm based on sampling distance transform. Accuracy and robustness was examined by repeat scan reproducibility under in-vivo condition and correlation between thickness values computed at ex-vivo and in-vivo resolution. Finally, the method was evaluated in a human study involving ...
A multispectral image fusion problem within the wavelet coefficient space has been studied in the... more A multispectral image fusion problem within the wavelet coefficient space has been studied in the present paper. In this algorithm, several kinds of area-based feature selection operators have been designed to select the image features in levels of the wavelet transform pyramids of source images. The problem of multiscale image enhancement and image fusion of different resolution has also been
Use the transform function theory to analyze the imaging characteristic of photo electronic imagi... more Use the transform function theory to analyze the imaging characteristic of photo electronic imaging system, and set up the simulation system for detecting characteristic of it with the high-speed DSP TMS320C6201. Through the simulation, we can evaluate the detecting characteristic of a certain photo electronic imaging system, change its components while simulating, and then compare the characteristic before change with
We present an apparatus to support real-time imaging for color night vision through fusion of inf... more We present an apparatus to support real-time imaging for color night vision through fusion of information derived from two channels of low-light CCD. The processing system is comprised of a bi-channel real-time video acquisition module, a low-light image pretreatment module, a core image fusion module, a real-time video output module and a user interface module. The bi-channel active videos are
Accurate measurement of the MTF for discrete imaging system can be obtained by viewing a known fr... more Accurate measurement of the MTF for discrete imaging system can be obtained by viewing a known frequency target. A slit target is frequently used to measure the MTF for an imaging system. Usually we have 4 methods to measure the MTF for a discrete imaging system using a slit. But for the discrete imaging systems of under sampling that is
Pyroelectric uncooled focal plane array (FPA) thermal imager has the advantages of low cost, smal... more Pyroelectric uncooled focal plane array (FPA) thermal imager has the advantages of low cost, small size, high responsibility and can work under room temperature, so it has great progress in recent years. As a matched technique, the modulate chopper has become one of the key techniques in uncooled FPA thermal imaging system. Now the Archimedes spiral cord chopper technique is
Multiple image registration plays a crucial role in multiple-sensor or multiple-spectral image fu... more Multiple image registration plays a crucial role in multiple-sensor or multiple-spectral image fusion. We present an improved multi-resolutional SSDA that bases on wavelet decomposition. When computing the alignment parameters, we use a coarse-to-fine updating strategy and proper preprocessing stage. This approach yields sub-pixel accuracy to multi-spectral images with 2D geometric transformation of translations, rotations and scale changes. Experiment results show
A mathematical model for the visual range prediction of thermal imaging systems, various factors ... more A mathematical model for the visual range prediction of thermal imaging systems, various factors affecting the visual range, as well as the relevant methods of computation are the topics covered. It is suggested that further revision is needed in consideration of the non-linear change of power versus temperature difference when the observed targets are involved in larger temperature difference cases.
The theory of realizing dual band thermal images by pyroelectric FPA detector with 4 states of ch... more The theory of realizing dual band thermal images by pyroelectric FPA detector with 4 states of chopper modulation is proposed. The rules governing the variations of signal responses to temperature rise from the scenery incident emission under 4 states of chopper modulation and successive signal processing in the detector are established. Analysis of the digital analog shows that the double
Dual-band uncooled Focal Plane Array (FPA) thermal imaging system adopts an Archimedes spiral cor... more Dual-band uncooled Focal Plane Array (FPA) thermal imaging system adopts an Archimedes spiral cord chopper and a matched dual-band light filter to achieve two single-band IR images in one imaging system. Traditional methods of getting two bands images need two single-band thermal imagers, this system only needs one detector and one optical imaging system, so the system's structure becomes smaller
Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is essential for qua... more Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is essential for quantification of vascular geometry useful to diagnose several pulmonary diseases. A multi-scale topo-morphologic opening algorithm has recently been introduced separating A/V trees via non-contrast CT imaging. The method starts with two sets of seeds — one for each of A/V trees and combines fuzzy distance transform,
ABSTRACT Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular... more ABSTRACT Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular dystrophy. Identifying such pulmonary artery/vein (A/V) tree dystrophy in terms of quantitative measures via CT imaging significantly facilitates early detection of disease or a treatment monitoring process. A tree structure, consisting of nodes and connected arcs, linked to the volumetric representation allows multi-level geometric and volumetric analysis of A/V trees. Here, a new theory and method is presented to generate multi-level A/V tree representation of volumetric data and to compute quantitative measures of A/V tree geometry and topology at various tree hierarchies. The new method is primarily designed on arc skeleton computation followed by a tree construction based topologic and geometric analysis of the skeleton. The method starts with a volumetric A/V representation as input and generates its topologic and multi-level volumetric tree representations long with different multi-level morphometric measures. A new recursive merging and pruning algorithms are introduced to detect bad junctions and noisy branches often associated with digital geometric and topologic analysis. Also, a new notion of shortest axial path is introduced to improve the skeletal arc joining two junctions. The accuracy of the multi-level tree analysis algorithm has been evaluated using computer generated phantoms and pulmonary CT images of a pig vessel cast phantom while the reproducibility of method is evaluated using multi-user A/V separation of in vivo contrast-enhanced CT images of a pig lung at different respiratory volumes.
Adult bone diseases, especially osteoporosis leads to increased risk of fracture which associated... more Adult bone diseases, especially osteoporosis leads to increased risk of fracture which associated with substantial morbidity, mortality and financial cost. Clinically osteoporosis is defined as low bone mineral density. However, increasing the evidence suggests that the micro architectural quality of Trabecular Bone (TB) is more determinant of bone strength and fracture risk. Here, we present a new robust algorithm for computing TB thickness and marrow spacing at a low resolution. The star line tracking algorithm that effectively deals with partial voluming effects in vivo imaging with voxel size comparable with thickness. Also the method avoids the problem of digitization associated with conventional algorithm based on sampling distance transform. Accuracy and robustness was examined by repeat scan reproducibility under in-vivo condition and correlation between thickness values computed at ex-vivo and in-vivo resolution. Finally, the method was evaluated in a human study involving ...
A multispectral image fusion problem within the wavelet coefficient space has been studied in the... more A multispectral image fusion problem within the wavelet coefficient space has been studied in the present paper. In this algorithm, several kinds of area-based feature selection operators have been designed to select the image features in levels of the wavelet transform pyramids of source images. The problem of multiscale image enhancement and image fusion of different resolution has also been
Use the transform function theory to analyze the imaging characteristic of photo electronic imagi... more Use the transform function theory to analyze the imaging characteristic of photo electronic imaging system, and set up the simulation system for detecting characteristic of it with the high-speed DSP TMS320C6201. Through the simulation, we can evaluate the detecting characteristic of a certain photo electronic imaging system, change its components while simulating, and then compare the characteristic before change with
We present an apparatus to support real-time imaging for color night vision through fusion of inf... more We present an apparatus to support real-time imaging for color night vision through fusion of information derived from two channels of low-light CCD. The processing system is comprised of a bi-channel real-time video acquisition module, a low-light image pretreatment module, a core image fusion module, a real-time video output module and a user interface module. The bi-channel active videos are
Accurate measurement of the MTF for discrete imaging system can be obtained by viewing a known fr... more Accurate measurement of the MTF for discrete imaging system can be obtained by viewing a known frequency target. A slit target is frequently used to measure the MTF for an imaging system. Usually we have 4 methods to measure the MTF for a discrete imaging system using a slit. But for the discrete imaging systems of under sampling that is
Pyroelectric uncooled focal plane array (FPA) thermal imager has the advantages of low cost, smal... more Pyroelectric uncooled focal plane array (FPA) thermal imager has the advantages of low cost, small size, high responsibility and can work under room temperature, so it has great progress in recent years. As a matched technique, the modulate chopper has become one of the key techniques in uncooled FPA thermal imaging system. Now the Archimedes spiral cord chopper technique is
Multiple image registration plays a crucial role in multiple-sensor or multiple-spectral image fu... more Multiple image registration plays a crucial role in multiple-sensor or multiple-spectral image fusion. We present an improved multi-resolutional SSDA that bases on wavelet decomposition. When computing the alignment parameters, we use a coarse-to-fine updating strategy and proper preprocessing stage. This approach yields sub-pixel accuracy to multi-spectral images with 2D geometric transformation of translations, rotations and scale changes. Experiment results show
A mathematical model for the visual range prediction of thermal imaging systems, various factors ... more A mathematical model for the visual range prediction of thermal imaging systems, various factors affecting the visual range, as well as the relevant methods of computation are the topics covered. It is suggested that further revision is needed in consideration of the non-linear change of power versus temperature difference when the observed targets are involved in larger temperature difference cases.
The theory of realizing dual band thermal images by pyroelectric FPA detector with 4 states of ch... more The theory of realizing dual band thermal images by pyroelectric FPA detector with 4 states of chopper modulation is proposed. The rules governing the variations of signal responses to temperature rise from the scenery incident emission under 4 states of chopper modulation and successive signal processing in the detector are established. Analysis of the digital analog shows that the double
Dual-band uncooled Focal Plane Array (FPA) thermal imaging system adopts an Archimedes spiral cor... more Dual-band uncooled Focal Plane Array (FPA) thermal imaging system adopts an Archimedes spiral cord chopper and a matched dual-band light filter to achieve two single-band IR images in one imaging system. Traditional methods of getting two bands images need two single-band thermal imagers, this system only needs one detector and one optical imaging system, so the system's structure becomes smaller
Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is essential for qua... more Distinguishing pulmonary arterial and venous (A/V) trees via in vivo imaging is essential for quantification of vascular geometry useful to diagnose several pulmonary diseases. A multi-scale topo-morphologic opening algorithm has recently been introduced separating A/V trees via non-contrast CT imaging. The method starts with two sets of seeds — one for each of A/V trees and combines fuzzy distance transform,
ABSTRACT Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular... more ABSTRACT Diseases like pulmonary embolism and pulmonary hypertension are associated with vascular dystrophy. Identifying such pulmonary artery/vein (A/V) tree dystrophy in terms of quantitative measures via CT imaging significantly facilitates early detection of disease or a treatment monitoring process. A tree structure, consisting of nodes and connected arcs, linked to the volumetric representation allows multi-level geometric and volumetric analysis of A/V trees. Here, a new theory and method is presented to generate multi-level A/V tree representation of volumetric data and to compute quantitative measures of A/V tree geometry and topology at various tree hierarchies. The new method is primarily designed on arc skeleton computation followed by a tree construction based topologic and geometric analysis of the skeleton. The method starts with a volumetric A/V representation as input and generates its topologic and multi-level volumetric tree representations long with different multi-level morphometric measures. A new recursive merging and pruning algorithms are introduced to detect bad junctions and noisy branches often associated with digital geometric and topologic analysis. Also, a new notion of shortest axial path is introduced to improve the skeletal arc joining two junctions. The accuracy of the multi-level tree analysis algorithm has been evaluated using computer generated phantoms and pulmonary CT images of a pig vessel cast phantom while the reproducibility of method is evaluated using multi-user A/V separation of in vivo contrast-enhanced CT images of a pig lung at different respiratory volumes.
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