计算机应用与软件
計算機應用與軟件
계산궤응용여연건
COMPUTER APPLICATIONS AND SOFTWARE
2013年
11期
8-12
,共5页
孟博%蒋慧琴%王忠勇%刘玉敏
孟博%蔣慧琴%王忠勇%劉玉敏
맹박%장혜금%왕충용%류옥민
低剂量CT%小波变换%匹配插值%三维重建
低劑量CT%小波變換%匹配插值%三維重建
저제량CT%소파변환%필배삽치%삼유중건
Low-dose CT%Wavelet transform%Matching interpolation%3D-reconstruction
层间插值是提高三维重建图像质量的一个重要手段。针对低剂量CT扫描导致X线量子噪声增加和整体分辨率下降的问题,提出一种小波域抑制噪声的匹配插值算法。该算法将断层图像变换到小波域后,对高频子图先采用软阈值法进行噪声抑制再进行线性插值获取插值后的高频子图。对低频子图利用匹配插值获取较精确的插值图像的低频子图。最后,基于处理过的子图通过小波逆变换得到插值图像。实验结果表明,提议算法能有效抑制噪声和较好地保持图像边缘等细节信息。三维重建的比较实验也表明,利用提议方法后的三维重建图像在噪声减少及去除梯田效应方面有较好效果。
層間插值是提高三維重建圖像質量的一箇重要手段。針對低劑量CT掃描導緻X線量子譟聲增加和整體分辨率下降的問題,提齣一種小波域抑製譟聲的匹配插值算法。該算法將斷層圖像變換到小波域後,對高頻子圖先採用軟閾值法進行譟聲抑製再進行線性插值穫取插值後的高頻子圖。對低頻子圖利用匹配插值穫取較精確的插值圖像的低頻子圖。最後,基于處理過的子圖通過小波逆變換得到插值圖像。實驗結果錶明,提議算法能有效抑製譟聲和較好地保持圖像邊緣等細節信息。三維重建的比較實驗也錶明,利用提議方法後的三維重建圖像在譟聲減少及去除梯田效應方麵有較好效果。
층간삽치시제고삼유중건도상질량적일개중요수단。침대저제량CT소묘도치X선양자조성증가화정체분변솔하강적문제,제출일충소파역억제조성적필배삽치산법。해산법장단층도상변환도소파역후,대고빈자도선채용연역치법진행조성억제재진행선성삽치획취삽치후적고빈자도。대저빈자도이용필배삽치획취교정학적삽치도상적저빈자도。최후,기우처리과적자도통과소파역변환득도삽치도상。실험결과표명,제의산법능유효억제조성화교호지보지도상변연등세절신식。삼유중건적비교실험야표명,이용제의방법후적삼유중건도상재조성감소급거제제전효응방면유교호효과。
Interpolation of medical cross-sectional images is an important means for improving the quality of 3D reconstruction images . Low-dose computed tomography ( CT ) scanning results in increased X ray quantum noise and reduced entire resolution .In light of this problem, we present a matching interpolation method which is based on wavelet domain noise suppression .In the algorithm, after the tomographic images have been transformed to wavelet domain , for high-frequency sub-images the soft thresholding method is employed to suppress the noise first , and then the linear interpolation is made to obtain high-frequency sub-images with interpolation .For low-frequency sub-images the matching interpolation is used to obtain fairly accurate low-frequency sub-image of the interpolated image .Finally, the interpolated image is reconstructed by inverse wavelet transform based on the processed sub -images.Experimental results demonstrate that the proposed method can effectively suppress the noise and well keep the detailed information such as boundaries of the images .Comparative experiments of 3D reconstruction also show that by applying the proposed interpolation method , 3D reconstruction images have good results in reducing the noise and eliminating the terracing effect .