问题描述
我是深度学习的新手,目前正在研究图像分割网络。我设法训练了网络,但问题是将网络响应转换为 nii 格式。我将 CT 图像中的训练样本切成 512X512 个切片,然后再切成 128X128 个补丁。因此,我将补丁转移到网络的输入端,并在输出端得到 128x128 的掩码。我设法将掩码分组到一个 numpy 数组中。但是当从一个数组转移到 nii 并试图将生成的掩码强加到原始 CT 上时,我的尺度不匹配。请告诉我可能是什么问题?我非常感谢您的帮助。
为了简单起见,我从训练样本中取了一个掩码。
input_path = PatchPathOutput
ls = os.listdir(input_path)#dir with patches(128) of inital mask
slices = []
for i in range(0,len(ls),16):
line1 = np.array(Image.open(input_path + '/'+ ls[i]))
#here I get the first slice line from patches
for j in range(1,4):
a = np.array(Image.open(input_path + '/'+ ls[i+j]))
line1 = np.concatenate((line1,a),axis = 1)
line2 = np.array(Image.open(input_path + '/'+ ls[i + 4]))
for j in range(5,8):
a = np.array(Image.open(input_path + '/'+ ls[i+j]))
line2 = np.concatenate((line2,axis = 1)
line3 = np.array(Image.open(input_path + '/'+ ls[i + 8]))
for j in range(9,12):
a = np.array(Image.open(input_path + '/'+ ls[i+j]))
line3 = np.concatenate((line3,axis = 1)
line4 = np.array(Image.open(input_path + '/'+ ls[i + 12]))
for j in range(13,16):
a = np.array(Image.open(input_path + '/'+ ls[i+j]))
line4 = np.concatenate((line4,axis = 1)
#all lines to slice (512 x 512)
slice_ = np.concatenate((line1,line2),axis = 0)
slice_ = np.concatenate((slice_,line3),line4),axis = 0)
slices.append(slice_)
slices_ = np.asarray(slices)#shape (137,512,512)
slices_ = np.swapaxes(slices_,2)#shape (512,137)
import nibabel as nib
new_image = nib.Nifti1Image(slices_,affine=np.eye(4))
nib.save(new_image,'new_image.nii')
解决方法
好吧,我意识到问题是什么,在保存时,您需要使用原始nii图像的仿射变换。
ct_scan = nib.load(CtPathInput + '/019.nii')
import nibabel as nib
new_image = nib.Nifti1Image(slices_,ct_scan.affine)
nib.save(new_image,'new_image.nii')