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OPTIMAL WAVELET FILTER DESIGN FOR REMOTE SENSING IMAGE COMPRESSION

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Journal of Electronics(China) 2007年第2期24卷 276-284页

作者： Yang guoan zheng Nanning Guo Shugang Institute of Artificial Intelligence and Robotics Xi＇an Jiaotong University Xi＇an 710049 China

A new approach for designing the Biorthogonal Wavelet Filter Bank (BWFB) for the purpose of image compression is presented in this letter. The approach is decomposed into two steps. First, an optimal filter bank is designed in theoretical sense based on Vaidyanathan’s coding gain criterion in SubBand Coding (SBC) system. Then the above filter bank is optimized based on the criterion of Peak Signal-to-Noise Ratio (PSNR) in JPEG2000 image compression system, resulting in a BWFB in practical application sense. With the approach, a series of BWFB for a specific class of applications related to image compression, such as remote sensing images, can be fast designed. Here, new 5/3 BWFB and 9/7 BWFB are presented based on the above approach for the remote sensing image compression applications. Experiments show that the two filter banks are equally performed with respect to CDF 9/7 and LT 5/3 filter in JPEG2000 standard; at the same time, the coefficients and the lifting parameters of the lifting scheme are all rational, which bring the computational advantage, and the ease for VLSI implementation.

关键词： Wavelet filter Optimization Coding gain Remote sensing image JPEG2000

Ptycho-endoscopy on a lensless ultrathin fiber bundle tip

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Light(Science & Applications) 2024年第9期13卷 1766-1778页

作者： Pengming Song Ruihai Wang Lars Loetgering Jia Liu Peter Vouras Yujin Lee Shaowei Jiang Bin Feng Andrew Maiden Changhuei Yang guoan zheng Department of Biomedical Engineering University of ConnecticutStorrsCT 06269USA CarlZeiss AG Carl Zeiss PromenadeJenaThuringia 07745Germany United States Department of Defense WashingtonDC 20301USA School of Electrical and Electronic Engineering Yonsei UniversitySeoul 03722Republic of Korea Department of Electronic and Electrical Engineering University of SheffieldSheffield South Yorkshire S13JDUK Diamond Light Source HarwellOxfordshire OX110DEUK Department of Electrical Engineering California Institute of TechnologyPasadenaCA 91125USA Center for Biomedical and Bioengineering Innovation University of ConnecticutStorrsCT 06269USA

Synthetic aperture radar(SAR)utilizes an aircraft-carried antenna to emit electromagnetic pulses and detect the returning *** the aircraft travels across a designated area,it synthesizes a large virtual aperture to improve image *** by SAR,we introduce synthetic aperture ptycho-endoscopy(SAPE)for micro-endoscopic imaging beyond the diffraction *** operates by hand-holding a lensless fiber bundle tip to record coherent diffraction patterns from *** fiber cores at the distal tip modulate the diffracted wavefield within a confined area,emulating the role of the‘airborne antenna’in *** handheld operation introduces positional shifts to the tip,analogous to the aircraft’s *** shifts facilitate the acquisition of a ptychogram and synthesize a large virtual aperture extending beyond the bundle’s physical *** mitigate the influences of hand motion and fiber bending through a low-rank spatiotemporal decomposition of the bundle’s modulation *** tests demonstrate the ability to resolve a 548-nm linewidth on a resolution *** achieved space-bandwidth product is~1.1 million effective pixels,representing a 36-fold increase compared to that of the original fiber ***,SAPE’s refocusing capability enables imaging over an extended depth of field exceeding 2 *** aperture synthesizing process in SAPE surpasses the diffraction limit set by the probe’s maximum collection angle,opening new opportunities for both fiber-based and distal-chip endoscopy in applications such as medical diagnostics and industrial inspection.

关键词： fiber antenna bundle

Rapid full-color Fourier ptychographic microscopy via spatially filtered color transfer

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Photonics Research 2022年第10期10卷 2410-2421页

作者： JIURUN CHEN AIYE WANG AN PAN guoan zheng CAIWEN MA BAOLI YAO Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Space Precision Measurement Technology Xi’an 710119China Department of Biomedical Engineering University of ConnecticutStorrsConnecticut 06269USA

Full-color imaging is of critical importance in digital pathology for analyzing labeled tissue *** our previous cover story[***:Phys.,***.64,114211(2021)],a color transfer approach was implemented on Fourier ptychographic microscopy(FPM)for achieving high-throughput full-color whole slide imaging without mechanical *** approach was able to reduce both acquisition and reconstruction time of FPM by three-fold with negligible trade-off on color ***,the method cannot properly stain samples with two or more dyes due to the lack of spatial constraints in the color transfer *** also requires a high computation cost in histogram matching of individual *** we report a modified full-color imaging algorithm for FPM,termed color-transfer filtering FPM(CFFPM).In CFFPM,we replace the original histogram matching process with a combination of block processing and trilateral spatial *** former step reduces the search of the solution space for colorization,and the latter introduces spatial constraints that match the low-resolution *** further adopt an iterative process to refine the *** show that this method can perform accurate and fast color transfer for various specimens,including those with multiple *** statistical results of 26 samples show that the average root mean square error is only 1.26%higher than that of the red-green-blue sequential acquisition *** some cases,CFFPM outperforms the sequential method because of the coherent artifacts introduced by dust *** reported CFFPM strategy provides a turnkey solution for digital pathology via computational optical imaging.

关键词： transfer matching constraints

Review of bio-optical imaging systems with a high space-bandwidth product

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Advanced Photonics 2021年第4期3卷 1-18页

作者： Jongchan Park David J.Brady guoan zheng Lei Tian Liang Gao University of California Department of BioengineeringLos AngelesCaliforniaUnited States University of Arizona James C.Wyant College of Optical SciencesTucsonArizonaUnited States University of Connecticut Department of Biomedical EngineeringStorrsConnecticutUnited States University of Connecticut Department of Electrical and Computer EngineeringStorrsConnecticutUnited States Boston University Department of Electrical and Computer EngineeringBostonMassachusettsUnited States

Optical imaging has served as a primary method to collect information about biosystems across scales—from functionalities of tissues to morphological structures of cells and even at biomolecular ***,to adequately characterize a complex biosystem,an imaging system with a number of resolvable points,referred to as a space-bandwidth product(SBP),in excess of one billion is typically *** a gigapixel-scale far exceeds the capacity of current optical imagers,compromises must be made to obtain either a low spatial resolution or a narrow field-of-view(FOV).The problem originates from constituent refractive optics—the larger the aperture,the more challenging the correction of lens ***,it is impractical for a conventional optical imaging system to achieve an SBP over hundreds of *** address this unmet need,a variety of high-SBP imagers have emerged over the past decade,enabling an unprecedented resolution and FOV beyond the limit of conventional *** provide a comprehensive survey of high-SBP imaging techniques,exploring their underlying principles and applications in bioimaging.

关键词： space-bandwidth product bioimaging gigapixel imaging high resolution wide field of view

Light-field micro-endoscopy using a fiber bundle:a snapshot 3D epi-fluorescence endoscope

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Photonics Research 2022年第9期10卷 2247-2260页

作者： YOU ZHOU BO XIONG WEIZHI SONG XU ZHANG guoan zheng QIONGHAI DAI XUN CAO School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China Department of Automation Tsinghua UniversityBeijing 100084China Institute for Brain and Cognitive Sciences Tsinghua UniversityBeijing 100084 China Beijing Institute of Collaborative Innovation Beijing 100094China Department of Biomedical Engineering University of ConnecticutStorrsConnecticut 06269USA

Micro-endoscopes are widely used for detecting and visualizing hard-to-reach areas of the human body and for in vivo observation of animals.A micro-endoscope that can realize 3D imaging at the camera framerate could benefit various clinical and biological *** this work,we report the development of a compact light-field micro-endoscope(LFME)that can obtain snapshot 3D fluorescence imaging,by jointly using a single-mode fiber bundle and a small-size light-field *** demonstrate the real imaging performance of our method,we put a resolution chart in different z positions and capture the z-stack images successively for reconstruction,achieving 333-μm-diameter field of view,24μm optimal depth of field,and up to 3.91μm spatial resolution near the focal *** also test our method on a human skin tissue section and He La *** LFME prototype provides epi-fluorescence imaging ability with a relatively small(2-mm-diameter)imaging probe,making it suitable for in vivo detection of brain activity and gastrointestinal diseases of animals.

关键词： endoscope bundle fiber

Synthetic aperture ptychography:coded sensor translation for joint spatial-Fourier bandwidth expansion

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Photonics Research 2022年第7期10卷 1624-1632页

作者： PENGMING SONG SHAOWEI JIANG TIANBO WANG CHENGFEI GUO RUIHAI WANG TERRANCE ZHANG guoan zheng Department of Biomedical Engineering University of ConnecticutStorrsConnecticut 06269USA

Conventional ptychography translates an object through a localized probe beam to widen the field of view in real *** ptychography translates the object spectrum through a pupil aperture to expand the Fourier bandwidth in reciprocal *** we report an imaging modality,termed synthetic aperture ptychography(SAP),to get the best of both *** SAP,we illuminate a stationary object using an extended plane wave and translate a coded image sensor at the far field for data *** coded layer attached on the sensor modulates the object exit waves and serves as an effective ptychographic probe for phase *** sensor translation process in SAP synthesizes a large complex-valued wavefront at the intermediate aperture *** propagating this wavefront back to the object plane,we can widen the field of view in real space and expand the Fourier bandwidth in reciprocal space *** validate the SAP approach with transmission targets and reflection silicon microchips.A 20-mm aperture was synthesized using a 5-mm sensor,achieving a fourfold gain in resolution and 16-fold gain in field of view for object *** addition,the thin sample requirement in ptychography is no longer required in *** can digitally propagate the recovered exit wave to any axial position for post-acquisition *** SAP scheme offers a solution for far-field sub-diffraction imaging without using *** can be adopted in coherent diffraction imaging setups with radiation sources from visible light,extreme ultraviolet,and X-ray,to electron.

关键词： translate ptychography translation

Incoherent Fourier ptychographic photography using structured light

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Photonics Research 2015年第1期3卷 19-23页

作者： Siyuan Dong Pariksheet Nanda Kaikai Guo Jun Liao guoan zheng Biomedical Engineering University of Connecticut Electrical and Computer Engineering University of Connecticut

Controlling photographic illumination in a structured fashion is a common practice in computational photography and image-based rendering. Here we introduce an incoherent photographic imaging approach, termed Fourier ptychographic photography, that uses nonuniform structured light for super-resolution imaging. In this approach,frequency mixing between the object and the structured light shifts the high-frequency object information to the passband of the photographic lens. Therefore, the recorded intensity images contain object information that is beyond the cutoff frequency of the collection optics. Based on multiple images acquired under different structured light patterns, we used the Fourier ptychographic algorithm to recover the super-resolution object image and the unknown illumination pattern. We demonstrated the reported approach by imaging various objects, including a resolution target, a quick response code, a dollar bill, an insect, and a color leaf. The reported approach may find applications in photographic imaging settings, remote sensing, and imaging radar. It may also provide new insights for high-resolution imaging by shifting the focus from the collection optics to the generation of structured light.

关键词： FPP OTF high

Influence of Zn ion implantation on structures and field emission properties of multi-walled carbon nanotube arrays

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Science China(Technological Sciences) 2010年第3期53卷 776-781页

作者： CHEN KeFan,DENG JianHua,ZHAO Fei,CHENG guoan &zheng RuiTing Key Laboratory of Beam Technology and Material Modification of Ministry of Education,College of Nuclear Science and Technology,Beijing Normal University,Beijing100875,China 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education College of Nuclear Science and Technology Beijing Normal University Beijing 100875 China

The structures and field emission properties of multi-walled carbon nanotube arrays implanted with Zn+ by MEVVA ion implanter have been *** results revealed that Zn+implantation induced structural damage and that the top of carbon nanotubes with multi-layered graphite structure were transformed into carbon nanowires with amorphous ***,C:Zn solid solution was synthesized after Zn+ *** turn-on field and threshold field were 0.80 and 1.31 V/μm,respectively for original multi-walled carbon nanotube arrays and were reduced to 0.66 and 1.04 V/μm due to the synthesis of C and Zn composite,in which the work function was reduced after low doses of Zn+*** is indicated that low doses of Zn+implantation can improve field emission performance of multi-walled carbon nanotube ***,high doses of Zn+implantation can reduce field emission properties of multi-walled carbon nanotube arrays,because radiation damage reduces the electric field enhancement factor.

关键词： multi-walled carbon nanotubes ion implantation field electron emission

Lensless polarimetric coded ptychography for high-resolution,high-throughput gigapixel birefringence imaging on a chip

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Photonics Research 2023年第12期11卷 2242-2255页

作者： LIMING YANG RUIHAI WANG QIANHAO ZHAO PENGMING SONG SHAOWEI JIANG TIANBO WANG XIAOPENG SHAO CHENGFEI GUO RISHIKESH PANDEY guoan zheng School of Optoelectronic Engineering Xidian UniversityXi’an 710071China Department of Biomedical Engineering University of ConnecticutStorrsConnecticut 06269USA

Polarimetric imaging provides valuable insights into the polarization state of light interacting with a *** can infer crucial birefringence properties of specimens without using labels,thereby facilitating the diagnosis of diseases such as cancer and *** this study,we present a novel polarimetric coded ptychography(pol-CP)approach that enables high-resolution,high-throughput gigapixel birefringence imaging on a *** platform deviates from traditional lens-based systems by employing an integrated polarimetric coded sensor for lensless coherent diffraction *** Jones calculus,we quantitatively determine the birefringence retardance and orientation information of biospecimens from the recovered *** portable pol-CP prototype can resolve the 435 nm linewidth on the resolution target,and the imaging field of view for a single acquisition is limited only by the detector size of 41 *** prototype allows for the acquisition of gigapixel birefringence images with a 180 mm^(2) field of view in~3.5 min,a performance that rivals high-end whole slide scanner but at a small fraction of the *** demonstrate its biomedical applications,we perform high-throughput imaging of malaria-infected blood smears,locating parasites using birefringence *** also generate birefringence maps of label-free thyroid smears to identify thyroid ***,the recovered birefringence maps emphasize the same regions as autofluorescence images,underscoring the potential for rapid on-site evaluation of label-free *** approach provides a turnkey and portable solution for lensless polarimetric analysis on a chip,with promising applications in disease diagnosis,crystal screening,and label-free chemical imaging,particularly in resource-constrained environments.

关键词： polarization birefringence resolution