將nii文件CT圖像更改窗寬窗位之后保存成nii文件

因為項目需要把CT圖像中骨頭更加明確的顯示出來，且還需要保存nii文件，所以查了一些資料，在這里做一下筆記，方便以后使用。代碼如下：

import nibabel as nib
import numpy as np
import SimpleITK as sitk
center = 350  # 窗位
width = 1200  # 窗寬

filename = 'E:/個人/骨折檢測/分割項目/HDC-Net-master/mydata/RibFrac1-image.nii.gz'
img = nib.load(filename)
img_fdata = img.get_fdata()

min = (2 * center - width) / 2.0 + 0.5
max = (2 * center + width) / 2.0 + 0.5
      
dFactor = 255.0 / (max - min)

img_fdata[img_fdata<min] = min
img_fdata[img_fdata>max] = max
# 進行轉置，因為需要按照原來的方向進行保存
data = np.transpose(img_fdata, [2, 1, 0])
(z, y, x) = data.shape
print(z," ",y," ",x)
for i in range(z):
    for j in range(x):
        for k in range(y):
            value = data[i,j,k]
            if value <= min:
                value = 0
            elif value < max:
                value = (value - min) / width * 255
            elif value >= max:
                value = 255
            else:
                data[i,j,k] = value 
#進行保存
print("-----------------")
filesname = "RibFrac1.nii.gz"            
img = sitk.GetImageFromArray(data)
sitk.WriteImage(img, filesname)
print("+++++++++++++++++")