image-derived data 中文意思是什麼
image-derived data
解釋
像析數據-
In the terms of interpolation, the image reconstructed from nearest interpolation or linear interpolation has good edge but serious noise ; reconstruction from 4 * 4cubic interpolation or three b - spline or three - order lagrange interpolations has better local character. 2 x 2cubic interpolations which has both better edge and local character is the ideal interpolation, the following is the basic principle during reconstruction : ( 1 ) the more width of interpolation, the more number of summation and the more order of interpolation polynomial, the higher of density resolution ; ( 2 ) the more of interpolation polynomial and width of interpolation, the more of reconstruction time simultaneously, aimed at eliminating the effects of noise contained in projection data, in this paper, author analysis cause and effects of common artifacts. importantly, discusses convolution back - projection reconstruction algorithm with a shift axis of rotation has been derived for correcting images that acquired with a divergence axis of rotation using the fan beam geometry with an angle - equaled detector
在ct圖像重建時，選擇有限帶寬窗有較好的空間解析度，三角形窗有較好的密度解析度，選擇餘弦窗則使得空間解析度與密度解析度的折衷；從窗函數的頻譜角度來講，可以用於圖像重建的一個良好的卷積窗函數應該具備以下條件： （ ? ）小的3db帶寬b ，即最小的主瓣寬度； （ ? ）最小的旁瓣最大峰值a ； （ ? ）最大的旁瓣峰值衰減速度d ；就內插函數而言，臨近點內插與線性內插重建圖像噪聲大，但有較好的邊緣與細節； 4 4三次內插、三次b -樣條與四次拉格朗日多項式內插圖像平滑，局部特性較好。 -
Since the real polarimetric sar data was derived in the mid 1980s, it has been proved that using polarimetric information can improve performance of sar image processing and application, and not only provide better understanding and interpretation for the radar observations, but also produce more new functions, such as terrain height measured technology
自從八十年代中期人們能夠獲取真實的機載極化sar數據以來，極化sar信息的使用已經證明能夠人人改進信號處理的質量和拓展新的應用功能。由於極化sar遙感有著極其重要的軍用和民用價值，因而受到世界各國科學家的普遍重視。
分享友人