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Electrical and Computer Engineering

Utah State University

Electrical and Computer Engineering Faculty Publications

2006

Articles 1 - 2 of 2

Full-Text Articles in Engineering

Classified Vector Spiht For Wavelet Image Coding, Y. Liang, Scott E. Budge Oct 2006

Classified Vector Spiht For Wavelet Image Coding, Y. Liang, Scott E. Budge

Electrical and Computer Engineering Faculty Publications

Wavelet based image coding has been shown to be an effective method, especially at low bit rate. Two successful approaches, space-frequency quantization (SFQ) and set partitioning in hierarchical trees (SPIHT) were proposed to predict insignificant wavelet coefficients. However, both of them employ a simple scalar quantization scheme instead of powerful vector quantization for coding of the significant wavelet coefficients. In this paper we propose a new image coding method that combines the SPIHT type set partitioning technique with classified vector quantization. That is, the set partitioning technique is used to locate significant wavelet coefficient vectors based on vectors' energies. In …


Simulation And Modeling Of Return Waveforms From A Ladar Beam Footprint In Usu Ladarsim, Scott E. Budge, B.C. Leishman, R.T. Pack May 2006

Simulation And Modeling Of Return Waveforms From A Ladar Beam Footprint In Usu Ladarsim, Scott E. Budge, B.C. Leishman, R.T. Pack

Electrical and Computer Engineering Faculty Publications

Ladar systems are an emerging technology with applications in many fields. Consequently, simulations for these systems have become a valuable tool in the improvement of existing systems and the development of new ones. This paper discusses the theory and issues involved in reliably modeling the return waveform of a ladar beam footprint in the Utah State University LadarSIM simulation software. Emphasis is placed on modeling system-level effects that allow an investigation of engineering tradeoffs in preliminary designs, and validation of behaviors in fabricated designs. Efforts have been made to decrease the necessary computation time while still maintaining a usable model. …