視訊編碼器超大型積體電路設計之整體考量

Abstract

本論文乃探討CCITT之視訊電話傳送標準H.261影像壓縮編碼晶片，以成本 的觀點來考量商品化的最佳可行性。由於此視訊電話傳送標準的編碼系統 含有移動估測補償、離散餘弦函數轉換、量化、不定長度編碼等等壓縮技 術。本文將以整個系統最佳化為目標，尋求各個壓縮單元間彼此最有效率 的經濟連貫，尤其在各壓縮單元架構的決定、系統運算週期(脈鐘)的同步 問題、硬體實現時一般電路及記憶體的差異、資料匯流排的連接個數、記 憶體的數量，以及晶片對外的接腳個數和晶片製程技術種類的選用，均列 為商品化成本的考量。 This thesis is focused on the system-level design of the image compression coder chip for the CCITT H.261 standard. An H.261 coder consists of several operation units such as motion estimation, discrete cosine transform, quantization, and variable length coding etc. This thesis places more emphasis on how to make efficient and economical connections between various units. The issues under consideration are system operating frequency, system synchronization, general logic vs. memory circuit, the number of external bus, and processing fabrication technologies.