Investigation of Vector Quantization for the Coding Gray Scale Images for Group 4 Facsimile

摘要

Vector Quantization is a new gray scale coding technique showing the promise of large compression ratios and good picture quality. No comprehensive study analyzing Vector Quantization, as applied to Group 4 facsimile systems under carefully controlled conditions, has been performed prior to this investigation. The purpose of this study was to evaluate Vector Quantization to determine its relative effectiveness for the addition of gray scale to Group 4 facsimile. This report is comprised of six sections. Section 1.0 provides a brief synopsis of the study objectives and outlines its results and conclusions. Section 2.0 describes the initial investigation, includes a highly simplified description of the Vector Quantization concept, and concludes with a brief outline of the selected approach and the reasons for its selection. Section 3.0 gives a system overview. Section 4.0 describes the system in detail. Section 5.0 presents the simulation parameters and results. Section 6.0 closes the report with conclusions and recommendations for future investigation. (fr)