霍氏轉換(Hough Transform) 最早被用來偵測直線，後來被加以延伸，變成可以偵測圓，橢圓以及任意形狀物件。它主要的缺點是需要大量的計算以及儲存空間，這些都和曲線的維數成次方關係。因而很多研究者都出改進的作法，希望能讓偵測更有效率，更節省記憶體。
由於PC功能愈來愈強，用來作為影像處理十分方便，因此幾乎所有圓形辨識的研究都是利用軟體為基礎完成，甚少以從硬體的觀點來探討。本論文則是從硬體觀念出發，提出一種架構並且利用FPGA搭配靜態記憶體(SRAM)達成快速圓形辨識的工作。
近代FPGA由於使用先進半導體製程製造，因此都能以快速的時脈運行而且由於內嵌大量記憶體，所以十分適用於本製作。由於偵測過程中必須使用緩衝記憶體，以及希望使用最少的外部零件，所以選用的FPGA必需至少內嵌1,576,960位元(bit)。靜態記憶體實際需求為64K*32位元，則可以使用一般的256KB SRAM來代用。未使用任何合成命令下，佈局之後的報告顯示本電路最高執行頻率約為5.8MHz。

The Hough Transform (Hough, 1962) has been used to characterize analytic features. It was first applied to the recognition of straight lines, and later extended to circles, ellipses and arbitrary shaped objects. Its main disadvantage is the computational and storage requirements increase as a power of the dimensionality of the curve. Many researchers have devoted themselves to the modifications of HT to detect circles and ellipses more efficiently, therefore.
It is not difficult to implement Circular Hough Transform (CHT) algorithm on modern personal computer. However, we intend to use FPGA or ASIC to perform CHT in this article. Modern FPGAs are capable of performing high speed operation and have large amount of embedded memory. The whole CHT circuitry with accumulator array excluded can be fitted into Altera® Stratix® 1S25 chip which has more than 1Mb RAM embedded.
The external SRAM serve as accumulator memory for center location accumulation. The size of the accumulators are 64K*32bit which can be replaced by any general SRAM chip. According to the reports generated by FPGA development tool, the highest speed of the main clock is 5.8MHz.

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