sitk.GetArrayFromImage returns 空 numpy 数组？

Question

我正在处理 3D MR 图像数据。为了计算直方图，我从 sitk.Image 转换为 3 维的 numpy 数组。虽然我能够使用 matplotlib 显示每个轴向切片，但 numpy 数组在所有三个维度上都是完全空的。谁能解释一下这是怎么回事？

import numpy as np
import SimpleITK as sitk
from myshow import myshow

img = sitk.ReadImage("mri.hdr")
nda = sitk.GetArrayFromImage(img)
myshow(img)
print nda

输出：

[[[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]

 [[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]

 [[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]

 ..., 
 [[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]

 [[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]

 [[ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  ..., 
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]
  [ 0.  0.  0. ...,  0.  0.  0.]]]

备注：

myshow.py (https://github.com/InsightSoftwareConsortium/SimpleITK-Notebooks/blob/master/Python/myshow.py)
myshow.py 使用matplotlib
MR 图像数据采用 hdr/img（分析）格式。

Answer 1

你很好。数据就在那里，只是打印函数显示了数组开头的数据（它很大）。如果您打印具有内容的特定像素的数据，您将看到一个有效值：

print nda[200,56,87]

假定索引在有效范围内。

sitk.GetArrayFromImage returns 空 numpy 数组？

sitk.GetArrayFromImage returns empty numpy array?

python

numpy

matplotlib

simpleitk