本論文提出一個快速影像尺寸縮小方法，所提方法在頻率域對JPEG2000 影像進行影像尺寸縮小工作。跟傳統在空間域縮小JPEG2000 影像尺寸的作法相比，本論文所提方法，可有效降低記憶體空間需求以及執行時間。實驗結果顯示，將輸入影像的尺寸縮小為原來的1/2n×1/2n 大小時，使用我們所提的快速影像尺寸縮小轉換方法，平均執行速度比在空間域進行影像尺寸轉換可節省6% ~73% 縮小影像尺寸轉換所需的執行時間。 This paper presents a fast downsizing method for JPEG 2000 images. The proposed method is used to downsize the JPEG 2000 images under frequency domain. Compared with the traditional method, which downsizes the JPEG 2000 images under spatial domain, our proposed method can effectivelyreduce both required memory space and execution time. Experimental results reveal that the proposed frequency domain downsizing method can reduce the average execution time of the spatial domain downsizing method by 6% to 73% for images are downscaled to 1/2n×1/2n of the original image sizes.
