近年來，廣角攝影機廣泛地應用在各種領域：如監視、醫療以及航空等等。由於廣角攝影機所取得的影像，通常會受到桶狀扭曲（barrel distortion）效應的影響，因此需要使用適當的演算法來對桶狀扭曲廣角影像進行修正。
為了修正扭曲影像，通常需取得原始影像中的兩個參數，一是像素點與扭曲中心點的距離，另一個是像素點與扭曲中心點連線和水平線的夾角，以進行桶狀扭曲的修正。傳統的作法乃是利用座標轉換器（CORDIC）的硬體來計算出距離與夾角，但這樣的方式需要大量的運算時間和極高的硬體成本。
本論文提出一個低成本的桶狀扭曲影像修正電路VLSI架構，藉由利用放射狀扭曲的特性和長度比例的相關聯性，來達成有效率的硬體實現。電路架構是以管線化的的方式來設計並使用TSMC 0.18 標準元件庫來合成實現。合成結果顯示，所須的邏輯閘數為45128，並可達到150 MHz之工作時脈。

In recent years, the wide-angle camera is widely used in many fields, ranging from surveillance to medical imaging. However, images captured by wide-angle lens suffer from barrel distortion. A suitable algorithm is necessary to correct the distorted images.
To perform barrel distortion correction, we usually need to calculate the distance between the pixel to be corrected and the distorted center of the wide-angle camera, and the included angle of the distance and horizontal axis. The traditional hardware implementation obtains the distance and angle by using the technique of the coordinate rotation digital computer (CORDIC). However, this kind of implementation requires extensive computational time and higher hardware cost.
In this thesis, a low-cost barrel distortion correction VLSI circuit that exploits both characteristic of radius distortion model and ratio of the length is presented. The proposed architecture is designed with the pipelined technique and implemented with TSMC 0.18 cell library. Synthesis results show that our design contains 44992 gate counts and operates at a clock rate of 150 MHz.

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