符合JPEG2000之離散小波轉換與反轉換硬體設計

Abstract

離散小波轉換的技術，已被廣泛的應用於訊號分析與影像處理的問題上。由於小波轉換後的係數呈現能量集中低頻的特性，非常適合影像資料壓縮的前處理。新的工業界標準中如JPEG2000、MPEG4已使用離散小波轉換取代離散餘弦轉換。 基於此，本論文將針對一維一層、一維多層與二維多層離散小波轉換的硬體架構，提出符合JPEG2000標準的離散小波轉換硬體設計。除了可輕易整合離散小波轉換與反轉換之外，更可以利用模組化的設計觀念，在不同的硬體架構上實現。 在本論文中，我們分別使用了二種不同的架構實現一維多層DWT。並以一維多層的硬體為基礎，配合二維控制器應用於二維多層DWT的硬體設計。 最後藉由Synopsys與Avant! tool模擬與合成實際的晶片以後，不管在圖形處理能力、運算速度或晶片面積上皆具有不錯的表現。

The discrete wavelet transform (DWT) technique has been widely used in signal processing and image processing. Since the DWT coefficients have the property of energy conservation in the low frequency part, it is suitable for data compression. In the recent industry standard, DWT has replaced DCT which is a main approach in image compression in JPEG2000 and MPEG4. Due to the drawback, the thesis focuses on the hardware architectures of 1-layer 1- dimensional DWT, multi-layer 1-dimensional DWT and Multi-layer 2-dimensional DWT which are the standard of JPEG2000. Based on the architecture, DWT and the inverse discrete wavelet transform (IDWT) can be integrated easily. Furthermore we can use the module design concept to implement DWT by different hardware architectures. Moreover, in the thesis, we use two different architectures to implement the multi-layer 1-dimensional DWT. Besides, accompanied with “2D-controller”the multi-layer 1-dimensional DWT can be adopted in multi-layer 2-dimension DWT hardware architecture. Consequently, the gate level simulation and P&R are done with Synopsys and Avant! tools. The chip has advantages in the ability of image processing, execution time and chip area.