臺灣博碩士論文加值系統

藉由整合平滑和銳化功能，二維LUM濾波器在影像處理應用上更具潛力。本論文提出可程式化二維濾波器之硬體架構實現，在此架構中包含三主要單元，分別為輸入管理、排序及比較等三單元。在輸入管理單元中包含一個產生器提供可程式化遮罩視窗且將一維訊號轉為二維訊號。在排序單元中，包括五個以PBF為基礎的濾波器，依可程式化輸入參數求得排序資料。第三單元提供一個資料格式轉換器及用以決定輸出值的邏輯電路。整個架構以Max+Plus II Altera模擬並以FPGA實現，其運算速度可達28.40MHz。

With the capability of combining smoothing and sharpening functions, the two-dimensional (2-D) Lower-Upper-Middle (LUM) filter has significant potential for many applications of image processing. This paper presents a programmable VLSI architecture to implement the 2D LUM filter. The architecture is consisted of three main units of the input data management, sorting, and comparison. The input data management includes a programmable window size generator and 1-D to 2-D converter. The sorting unit applies five PBF-based filters, which are modified to be programmable for finding desired rank data. The third unit includes bit format transformer and Boolean logic circuit for output determination. The architecture has been completely simulated on Max+plus II Altera and implemented in FPGA with 28.40 MHz performances.

中文摘要………………………………………………………… Ⅰ
英文摘要………………………………………………………… II
致謝……………………………………………………………… IV
目錄……………………………………………………………… V
圖目錄…………………………………………………………… VII
表目錄…………………………………………………………… X
第一章 緒論……………………………………………………… 1
1-1 LUM濾波器在應用上的重要性及優點……………………… 1
1-2 VLSI實現的需求及相關實現方法回顧…………………… 4
1-3 論文架構說明……………………………………………… 8
第二章 二維濾波器回顧及LUM濾波器簡介…………………… 10
2-1 二維空間濾波器(Spatial Filter)……………………… 10
2-1-1 低通濾波器……………………………………………… 13
2-1-2 高通濾波器……………………………………………… 15
2-1-3 帶通濾波器……………………………………………… 16
2-1-4 二維中值濾波器之快速演算法………………………… 17
2-2 LUM濾波器簡介……………………………………………… 20
2-2-1 視窗函數之定義………………………………………… 20
2-2-2 LUM平滑器(Smoother)…………………………………… 21
2-2-3 LUM銳化器(Sharpener)………………………………… 23
2-2-4 LUM濾波器………………………………………………… 25
第三章 排序法的原理回顧……………………………………… 28
3-1 Stack濾波器……………………………………………… 28
3-2 以正布林函數為基礎之濾波器…………………………… 30
3-2-1 PBF演算法………………………………………………… 30
3-2-2 以Bit-Serial實現數位架構…………………………… 33
3-2-3 定理證明………………………………………………… 36
3-3 LUM銳化器(Sharpener) ………………………………… 36
3-4 LUM濾波器………………………………………………… 42
第四章 二維LUM濾波器之VLSI架構…………………………… 43
4-1 可程式化資料輸入管理架構……………………………… 44
4-2 排序單元…………………………………………………… 48
4-3 比較輸出單元……………………………………………… 52
4-4 整體架構…………………………………………………… 60
第五章 硬體實現及performance分析………………………… 62
5-1 可程式化資料管理架構模擬……………………………… 63
5-2 時脈控制電路模擬………………………………………… 67
5-3 中心點位移架構模擬……………………………………… 68
5-4 排序架構模擬……………………………………………… 70
5-5 比較輸出單元模擬………………………………………… 77
5-6 整體架構模擬……………………………………………… 81
第六章 結論與未來展望…………………………………… … 92
參考文獻………………………………………………………… 95

[1] R. Gonzalez and R. E. Woods, “Digital Image Processing,” Addison Wesley, ch.4, pp.189-190. 1987.
[2] G. R. Arce and M. P. Mcloughlin, “Theoretical analysis of max/median filters,” IEEE Trans. Acoust., Speech, Signal Processing, vol. ASSP- 35, no. 1, Jan. 1987.
[3] S. C. Matz and Rui. J. P. de Figueiredo, “A nonlinear technique for image contrast enhancement and sharpening,” in Proc. IEEE International Symposium, Circuits and Systems, vol.4, 1999, pp. 175 —178.
[4] S. C. Hsia and C. L. Chen, “A fast efficient restoration algorithm for high-noise-ratio image using feature adaptive approach,” in Proc. IEEE International Symposium on Multimedia Software Engineering, 2000, pp. 265—268.
[5] R. C. Hardie and C. G. Boncelet, “LUM Filters：A class of rank-order-based filters for smoothing and sharpening”, IEEE Trans. Signal Processing, vol.41, no. 3, pp. 1064 —1076, Mar. 1993.
[6] 彭雲忠，“二維LUM濾波器快速演算法之研究”，義守大學電子工程碩士論文，民國九十年六月。
[7] Ashok Ambardar, “Analog and Digital Dignal Processing — 2nd,” Brooks cole 1999, ch. 9, pp.248-275.
[8] Rafael C. Gonzalez, Richard E. Woods, “Digital Image Processing,” Addison Wesley 1987, ch. 4, pp.190-202.
[9] Aggelos K. Katsaggelos, “Digital Image Restoration,” Springer- Verlag 1989, ch. 6, pp.153-159.
[10] T. S. Huang, G. J. Yang and G. Y. Tang, “A Fast Two-Dimensional Median Filtering Algorithm,” IEEE Trans. Acoust. Speech, Signal Processing, vol. ASSP-27, No. 1, Feb. 1979.
[11] T. Loupas, W. N. McDicken, and P. L. Allan, “An adaptive weighted median filter for speakle suppression in medical ultrasonic images,” IEEE Trans. Circuits Syst., vol. 36, Jan. 1989.
[12] S. J. Ko and Y. H. Lee, “Center weighted median filters and their applications to image enhancement,” IEEE Trans. Circuits Syst., vol. 38, no. 9, pp.984-993, Sept. 1991.
[13] K. Chen, “Bit-serial realization of a class of nonlinear filter on positive Boolean function”, IEEE Trans. Circuits Syst., vol. 36, no.6, pp. 785-794, June 1989.
[14] P. D. Wendt, E. J. Coyle, and N. C. Gallagher, “Stack filters,” IEEE Trans. Acoust., Speech, Signal Processing, vol. ASSP-34, pp.898-911, Aug. 1986.
[15] R. C. Hardie and C. G. Boncelet, “Gradient-based edge detection using nonlinear edge enhancing prefilters,” IEEE Trans. Image Processing, Issue 11, Vol. 4, Nov. 1995, Page(s). 1572 —1577.