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Full-Text Articles in Engineering
An Adaptive Intraframe Dpcm Codec Based Upon Nonstationary Image Model, N. F. Maxemchuk, J. A. Stuller
An Adaptive Intraframe Dpcm Codec Based Upon Nonstationary Image Model, N. F. Maxemchuk, J. A. Stuller
Electrical and Computer Engineering Faculty Research & Creative Works
This Paper Introduces a Nonstationary Model for Images and Develops an Adaptive Intrafield Dpcm Codec based Upon the Model. the Codec Attempts to Minimize the Mean‐square Coding Error at Each Sample Point in the Picture. the Quantizer in the Resulting Adaptive Codec is Found to Be Similar to that Previously Obtained from Visual Masking Considerations. Comparative Simulation Results using 256 X 256 Pixel Rasters Are Given for Two‐ and Three‐bit/pixel Versions of the Adaptive Codec, the Three‐bit/pixel Graham Codec, and Three‐bit/pixel Previous Element Dpcm. © 1979 the Bell System Technical Journal
Toward More Meaningful Laboratory Experiences In Digital Signal Processing And Digital Control, Rodger E. Ziemer, D. Ronald Fannin, Paul D. Stigall
Toward More Meaningful Laboratory Experiences In Digital Signal Processing And Digital Control, Rodger E. Ziemer, D. Ronald Fannin, Paul D. Stigall
Electrical and Computer Engineering Faculty Research & Creative Works
Digital Signal Processing and Digital Control Are of Utmost Importance for Electrical Engineering Students, for They Are Present in Many Aspects of Today's Technical World. Complex Topics Like These Should Not Be Introduced into a Curriculum as a Crash Program but Taken as Steps in an Evolutionary Process. a Successful Example of This Evolutionary Process is Well Underway at the University of Missouri-Rolla. Copyright © 1979 by the Institute of Electrical and Electronics Engineers, Inc.
Transform Domain Motion Estimation, J. A. Stuller, A. N. Netravali
Transform Domain Motion Estimation, J. A. Stuller, A. N. Netravali
Electrical and Computer Engineering Faculty Research & Creative Works
This Paper Introduces an Algorithm for Estimating the Displacement of Moving Objects in a Television Scene from Spatial Transform Coefficients of Successive Frames. the Algorithm Works Recursively in Such a Way that the Displacement Estimates Are Updated from Coefficient to Coefficient. a Promising Application of This Algorithm is in Motion‐compensated Interframe Hybrid Transform‐dpcm Image Coding. We Give a Statistical Analysis of the Transform Domain Displacement Estimation Algorithm and Prove its Convergence under Certain Realistic Conditions. an Analytical Derivation is Presented that Gives Sufficient Conditions for the Rate of Convergence of the Algorithm to Be Independent of the Transform Type. This …
A Microcomputer-Based Data Acquisition System With Hardware Capabilities To Calculate A Fast Fourier Transform, R. A. Kobylinski, Rodger E. Ziemer, Paul D. Stigall
A Microcomputer-Based Data Acquisition System With Hardware Capabilities To Calculate A Fast Fourier Transform, R. A. Kobylinski, Rodger E. Ziemer, Paul D. Stigall
Electrical and Computer Engineering Faculty Research & Creative Works
The Fast Fourier Transform (FFT) Has in Recent Years Become an Important Tool to the Engineer. There Are a Number of Algorithms Which Calculate the FFT. One Such Algorithm is the Cooley-Tukey FFT Algorithm (Radix-2) Which Lends itself Rather Easily to a Combination Software and Hardware Implementation. with a Microcomputer as the Controller of a Data Acquisition Module and Hardware Which Computes the Butterfly Associated with the FFT Algorithm, the FFT Can Be Calculated Efficiently. © 1979 IEEE
Backscatter Inversion In Spherically Asymmetric Ionosphere, R. (Richard) E. Dubroff, N. Narayana Rao, K. C. Yeh
Backscatter Inversion In Spherically Asymmetric Ionosphere, R. (Richard) E. Dubroff, N. Narayana Rao, K. C. Yeh
Electrical and Computer Engineering Faculty Research & Creative Works
It is Well Known that Various Diurnal and Morphological Features of the Ionosphere Reveal Substantial Departures from the Normally Simplified Assumption of Spherical Symmetry at Certain Times of the Day or at Certain Geographic Locations. a Radio Ray Passing through Such an Ionosphere Must Bear Information About its Horizontal Gradients. the Leading Edge of a Backscatter Ionogram is Formed by Obliquely Propagated Radio Rays of Minimum Time Delay and Hence is Useful in Deducing Information About the Ionospheric Horizontal Gradients. in This Regard, the Ionospheric Electron Density Distribution is Modeled by a Locally Quasi‐parabolic Layer with Six Parameters. This Six‐parameter …
Simple Generation Of One-Parameter Pseudoterrain Surfaces, Gordon E. Carlson
Simple Generation Of One-Parameter Pseudoterrain Surfaces, Gordon E. Carlson
Electrical and Computer Engineering Faculty Research & Creative Works
A simple method for generating digital terrain surfaces as a function of only the terrain standard deviation is presented. This is accomplished by fitting a postulated autocorrelation model to actual terrain data. Observed relations between model parameters are used to obtain a one-parameter model. Copyright © 1979 by The Institute of Electrical and Electronics Engineers. Inc.
Motion‐Compensated Transform Coding, A. N. Netravali, J. A. Stuller
Motion‐Compensated Transform Coding, A. N. Netravali, J. A. Stuller
Electrical and Computer Engineering Faculty Research & Creative Works
Interframe Hybrid Transform/dpcm Coders Encode Television Signals by Taking a Spatial Transform of a Block of Picture Elements in a Frame and Predictively Coding the Resulting Coefficients using the Corresponding Coefficients of the Spatial Block at the Same Location in the Previous Frame. These Coders Can Be Made More Efficient for Scenes Containing Objects in Translational Motion by First Estimating the Translational Displacement of Objects and Then using Coefficients of a Spatially Displaced Block in the Previous Frame for Prediction. This Paper Presents Simulation Results for Such Motion‐compensated Transform Coders using Two Algorithms for Estimating Displacements. the First Algorithm, Which …
Reduction Of Transmission Error Propagation In Adaptively Predicted, Dpcm Encoded Pictures, N. F. Maxemchuk, J. A. Stuller
Reduction Of Transmission Error Propagation In Adaptively Predicted, Dpcm Encoded Pictures, N. F. Maxemchuk, J. A. Stuller
Electrical and Computer Engineering Faculty Research & Creative Works
A New Technique for Reducing Transmission Error Propagation in Adaptively Predicted, dpcm‐encoded Pictures is Described. the Basis for the Technique is a Generalization of the Notion of Predictor Output Attenuation, Described by Graham, to Include Attenuation of the Adaptive Prediction Function. Simulation Results Are Presented that Show that Application of the Technique to Graham's Codec Results in Significant Reduction in Error Propagation Without Degradation of Picture Quality. the Technique Requires No Increase in Transmission Rate. © 1979 the Bell System Technical Journal