994 research outputs found
Evaluation of Single-Chip, Real-Time Tomographic Data Processing on FPGA - SoC Devices
A novel approach to tomographic data processing has been developed and
evaluated using the Jagiellonian PET (J-PET) scanner as an example. We propose
a system in which there is no need for powerful, local to the scanner
processing facility, capable to reconstruct images on the fly. Instead we
introduce a Field Programmable Gate Array (FPGA) System-on-Chip (SoC) platform
connected directly to data streams coming from the scanner, which can perform
event building, filtering, coincidence search and Region-Of-Response (ROR)
reconstruction by the programmable logic and visualization by the integrated
processors. The platform significantly reduces data volume converting raw data
to a list-mode representation, while generating visualization on the fly.Comment: IEEE Transactions on Medical Imaging, 17 May 201
ProtoEXIST: Advanced Prototype CZT Coded Aperture Telescopes for EXIST
{\it ProtoEXIST1} is a pathfinder for the {\it EXIST-HET}, a coded aperture
hard X-ray telescope with a 4.5 m CZT detector plane a 9070 degree
field of view to be flown as the primary instrument on the {\it EXIST} mission
and is intended to monitor the full sky every 3 h in an effort to locate GRBs
and other high energy transients. {\it ProtoEXIST1} consists of a 256 cm
tiled CZT detector plane containing 4096 pixels composed of an 88 array
of individual 1.95 cm 1.95 cm 0.5 cm CZT detector modules
each with a 8 8 pixilated anode configured as a coded aperture
telescope with a fully coded field of view employing
passive side shielding and an active CsI anti-coincidence rear shield, recently
completed its maiden flight out of Ft. Sumner, NM on the 9th of October 2009.
During the duration of its 6 hour flight on-board calibration of the detector
plane was carried out utilizing a single tagged 198.8 nCi Am-241 source along
with the simultaneous measurement of the background spectrum and an observation
of Cygnus X-1. Here we recount the events of the flight and report on the
detector performance in a near space environment. We also briefly discuss {\it
ProtoEXIST2}: the next stage of detector development which employs the {\it
NuSTAR} ASIC enabling finer (3232) anode pixilation. When completed
{\it ProtoEXIST2} will consist of a 256 cm tiled array and be flown
simultaneously with the ProtoEXIST1 telescope
Spatial Augmented Reality Using Structured Light Illumination
Spatial augmented reality is a particular kind of augmented reality technique that uses projector to blend the real objects with virtual contents. Coincidentally, as a means of 3D shape measurement, structured light illumination makes use of projector as part of its system as well. It uses the projector to generate important clues to establish the correspondence between the 2D image coordinate system and the 3D world coordinate system. So it is appealing to build a system that can carry out the functionalities of both spatial augmented reality and structured light illumination.
In this dissertation, we present all the hardware platforms we developed and their related applications in spatial augmented reality and structured light illumination. Firstly, it is a dual-projector structured light 3D scanning system that has two synchronized projectors operate simultaneously, consequently it outperforms the traditional structured light 3D scanning system which only include one projector in terms of the quality of 3D reconstructions. Secondly, we introduce a modified dual-projector structured light 3D scanning system aiming at detecting and solving the multi-path interference. Thirdly, we propose an augmented reality face paint system which detects human face in a scene and paints the face with any favorite colors by projection. Additionally, the system incorporates a second camera to realize the 3D space position tracking by exploiting the principle of structured light illumination.
At last, a structured light 3D scanning system with its own built-in machine vision camera is presented as the future work. So far the standalone camera has been completed from the a bare CMOS sensor. With this customized camera, we can achieve high dynamic range imaging and better synchronization between the camera and projector. But the full-blown system that includes HDMI transmitter, structured light pattern generator and synchronization logic has yet to be done due to the lack of a well designed high speed PCB
The digital data processing concepts of the LOFT mission
The Large Observatory for X-ray Timing (LOFT) is one of the five mission
candidates that were considered by ESA for an M3 mission (with a launch
opportunity in 2022 - 2024). LOFT features two instruments: the Large Area
Detector (LAD) and the Wide Field Monitor (WFM). The LAD is a 10 m 2 -class
instrument with approximately 15 times the collecting area of the largest
timing mission so far (RXTE) for the first time combined with CCD-class
spectral resolution. The WFM will continuously monitor the sky and recognise
changes in source states, detect transient and bursting phenomena and will
allow the mission to respond to this. Observing the brightest X-ray sources
with the effective area of the LAD leads to enormous data rates that need to be
processed on several levels, filtered and compressed in real-time already on
board. The WFM data processing on the other hand puts rather low constraints on
the data rate but requires algorithms to find the photon interaction location
on the detector and then to deconvolve the detector image in order to obtain
the sky coordinates of observed transient sources. In the following, we want to
give an overview of the data handling concepts that were developed during the
study phase.Comment: Proc. SPIE 9144, Space Telescopes and Instrumentation 2014:
Ultraviolet to Gamma Ray, 91446
Full image-processing pipeline in field-programmable gate array for a small endoscopic camera
Endoscopy is an imaging procedure used for diagnosis as well as for some surgical purposes. The
camera used for the endoscopy should be small and able to produce a good quality image or video, to reduce
discomfort of the patients, and to increase the efficiency of the medical team. To achieve these fundamental
goals, a small endoscopy camera with a footprint of 1 mm × 1 mm × 1.65 mm is used. Due to the physical prop erties of the sensors and human vision system limitations, different image-processing algorithms, such as noise
reduction, demosaicking, and gamma correction, among others, are needed to faithfully reproduce the image
or video. A full image-processing pipeline is implemented using a field-programmable gate array (FPGA) to
accomplish a high frame rate of 60 fps with minimum processing delay. Along with this, a viewer has also
been developed to display and control the image-processing pipeline. The control and data transfer are done
by a USB 3.0 end point in the computer. The full developed system achieves real-time processing of the image
and fits in a Xilinx Spartan-6LX150 FPGA.info:eu-repo/semantics/publishedVersio
The Proposed High Energy Telescope (HET) for EXIST
The hard X-ray sky now being studied by INTEGRAL and Swift and soon by NuSTAR
is rich with energetic phenomena and highly variable non-thermal phenomena on a
broad range of timescales. The High Energy Telescope (HET) on the proposed
Energetic X-ray Imaging Survey Telescope (EXIST) mission will repeatedly survey
the full sky for rare and luminous hard X-ray phenomena at unprecedented
sensitivities. It will detect and localize (<20", at 5 sigma threshold) X-ray
sources quickly for immediate followup identification by two other onboard
telescopes - the Soft X-ray imager (SXI) and Optical/Infrared Telescope (IRT).
The large array (4.5 m^2) of imaging (0.6 mm pixel) CZT detectors in the HET, a
coded-aperture telescope, will provide unprecedented high sensitivity (~0.06
mCrab Full Sky in a 2 year continuous scanning survey) in the 5 - 600 keV band.
The large field of view (90 deg x 70 deg) and zenith scanning with
alternating-orbital nodding motion planned for the first 2 years of the mission
will enable nearly continuous monitoring of the full sky. A 3y followup pointed
mission phase provides deep UV-Optical-IR-Soft X-ray and Hard X-ray imaging and
spectroscopy for thousands of sources discovered in the Survey. We review the
HET design concept and report the recent progress of the CZT detector
development, which is underway through a series of balloon-borne wide-field
hard X-ray telescope experiments, ProtoEXIST. We carried out a successful
flight of the first generation of fine pixel large area CZT detectors
(ProtoEXIST1) on Oct 9, 2009. We also summarize our future plan (ProtoEXIST2 &
3) for the technology development needed for the HET.Comment: 10 pages, 13 figures, 2 tables, SPIE Conference "Astronomical
Telescopes and Instrumentation 2010"; to appear in Proceedings SPIE (2010
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