A projector/backprojector with slice-to-slice blurring for efficient three-dimensional scatter modeling





     Related Videos
How Movie Theaters Work

  • How Movie Theaters Work

  • A segment from Steve Spangler's mid-90's television show, News For Kids. Steve and a few friends hea...

 C or BAC? The first big that will fall!
MBA Lecture at ISBS, Skills Audit - Norman Clayton

     Related Groups
Projector
Flame projector
LCD projector

  • LCD projector

  • An LCD projector is a type of video projector for displaying...

 LCD projector

  • LCD projector

  • An LCD projector is a type of video projector for displaying...

 Handheld projector
Talaria projector
Beam projector
Livens Projector
Projector Records
Throw (projector)

Field: Engineering  DOWNLOAD  BOOKMARK REPORT
Twitter Facebook In MS Digg Stumble Share Mail
  •  Doc. Url:    Embed Code: 

  • IEEE  status
    (0) (0 Votes)
    		Views: (2003)  
    Date:     (Publication Date: Aug. 1999)  
    Pages:     ()

  • Author:  Zeng, G.L. Chuanyong Bai Gullberg, G.T.
    Dept. of Radiol., Utah Univ., Salt Lake City, UT, USA;

  • Abstract:Abstract Scatter correction is an important factor in single photon emission computed tomography (SPECT). Many scatter correction techniques, such as multiple-window subtraction and intrinsic modeling with iterative algorithms, have been under study for many years. Previously, the authors developed an efficient slice-to-slice blurring technique to model attenuation and system geometric response in a projector/backprojec tor pair, which was used in an ML-EM algorithm to reconstruct SPECT data. This paper proposes a projector/backprojec tor that models the three-dimensional (3-D) first-order scatter in SPECT, also using an efficient slice-to-slice blurring technique. The scatter response is estimated from a known nonuniform attenuation distribution map. It is assumed that the probability of detection of a first-order scattered photon from a photon that is emitted in a given source voxel and scattered in a given scatter voxel is proportional to the attenuation coefficient value at that voxel. Monte Carlo simulations of point sources and an MCAT torso phantom were used to verify the accuracy of the proposed projector/backprojec tor model. An experimental Jaszczak torso/cardiac phantom SPECT study was also performed. For a 64/spl times/64/spl times/64 image volume, it took 8.7 s to perform each iteration per slice on a Sun ULTRA Enterprise 3000 (167 MHz, 1 Gbyte RAM) computer, when modeling 3-D scatter, attenuation, and system geometric response functions. The main advantage of the proposed method is its easy implementation and the possibility of performing reconstruction in clinically acceptable time.

Write a Comment


     Related Documents
In Proc of ICCV Workshop on Projector-Camera Systems PROCAMS 03 Nice France Applications o...

  • In Proc of ICCV Workshop on Projector-Camera Systems PROCAMS 03 Nice France Appl...

  • How can interactive computer interfaces be created anywhere in a space without wiring or modifying objects or people? We propose using steerable projector-camera systems employing computer vision to realize such ?steerable interfaces. ? In this paper, we illustrate the potential of the new kinds of applications enabled by steerable interfaces and discuss the challenges imposed on computer vision through the presentation of four application prototypes: a collaborative assembly task coordinator; a multi-surface presentation viewer; a ubiquitous p...

 A self-correcting projector

  • A self-correcting projector

  • Abstract We describe a calibration and rendering technique for a projector that can render rectangular images under keystoned position. The projector utilizes a rigidly attached camera to form a stereo pair. We describe a very easy to use technique for calibration of the projector-camera pair using only black planar surfaces. We present an efficient rendering method to pre-warp images so that they appear correctly on the screen, and show experimental results.

 The projector project

  • The projector project

  • Abstract A good high-definition LCD projector can still set you back US $2000, but if your wiring and woodworking skills are up to speed, you can put one together for around $600. It's not like you have to build it from scratch. At least two companies, DIY for Life and DIY Projector Kits, sell kits and supplies that make this something any engineer could do in a weekend.

 The projector project

  • The projector project

  • Abstract A good high-definition LCD projector can still set you back US $2000, but if your wiring and woodworking skills are up to speed, you can put one together for around $600. It's not like you have to build it from scratch. At least two companies, DIY for Life and DIY Projector Kits, sell kits and supplies that make this something any engineer could do in a weekend.

 Advantages of a Projector

  • Advantages of a Projector

  • The projector is being frequently used in broad range of the photogrammetric measurements with the development of non-contact measurement in the close-range photogrammetry, because a projector can project any pattern onto the measured object for controlling and calculating. Before using a projector, the interior parameters of it have to be calibrated first. Hence, the projector calibration is a necessary and important preceding step. The paper proposes a flexible technique to make the calibration of a projector with a planar grid. This techniqu...

 A self-correcting projector

  • A self-correcting projector

  • Abstract We describe a calibration and rendering technique for a projector that can render rectangular images under keystoned position. The projector utilizes a rigidly attached camera to form a stereo pair. We describe a very easy to use technique for calibration of the projector-camera pair using only black planar surfaces. We present an efficient rendering method to pre-warp images so that they appear correctly on the screen, and show experimental results.

 737 projector for HSR flight tests
737 projector for HSR flight tests
737 projector for HSR flight tests
737 projector for HSR flight tests




























 

Powered free by PHPmotion