双线性插值扩大四维张量宽高至256,256python代码
时间: 2023-08-06 08:17:46 浏览: 93
以下是双线性插值扩大四维张量宽高至256,256的Python代码:
```python
import numpy as np
def bilinear_interpolation_4d(x, y, z, w, img):
x1, y1, z1, w1 = int(np.floor(x)), int(np.floor(y)), int(np.floor(z)), int(np.floor(w))
x2, y2, z2, w2 = x1+1, y1+1, z1+1, w1+1
if x2 >= img.shape[0]:
x2 = x1
if y2 >= img.shape[1]:
y2 = y1
if z2 >= img.shape[2]:
z2 = z1
if w2 >= img.shape[3]:
w2 = w1
Q11 = img[x1, y1, z1, w1]
Q21 = img[x2, y1, z1, w1]
Q12 = img[x1, y2, z1, w1]
Q22 = img[x2, y2, z1, w1]
Q13 = img[x1, y1, z2, w1]
Q23 = img[x2, y1, z2, w1]
Q14 = img[x1, y1, z1, w2]
Q24 = img[x2, y1, z1, w2]
Q15 = img[x1, y2, z2, w1]
Q25 = img[x2, y2, z2, w1]
Q16 = img[x1, y2, z1, w2]
Q26 = img[x2, y2, z1, w2]
Q17 = img[x1, y1, z2, w2]
Q27 = img[x2, y1, z2, w2]
Q18 = img[x1, y2, z2, w2]
Q28 = img[x2, y2, z2, w2]
x_ratio, y_ratio, z_ratio, w_ratio = x-x1, y-y1, z-z1, w-w1
x_opposite, y_opposite, z_opposite, w_opposite = 1-x_ratio, 1-y_ratio, 1-z_ratio, 1-w_ratio
pixel_value = (
Q11*x_opposite*y_opposite*z_opposite*w_opposite +
Q21*x_ratio*y_opposite*z_opposite*w_opposite +
Q12*x_opposite*y_ratio*z_opposite*w_opposite +
Q22*x_ratio*y_ratio*z_opposite*w_opposite +
Q13*x_opposite*y_opposite*z_ratio*w_opposite +
Q23*x_ratio*y_opposite*z_ratio*w_opposite +
Q14*x_opposite*y_opposite*z_opposite*w_ratio +
Q24*x_ratio*y_opposite*z_opposite*w_ratio +
Q15*x_opposite*y_ratio*z_ratio*w_opposite +
Q25*x_ratio*y_ratio*z_ratio*w_opposite +
Q16*x_opposite*y_ratio*z_opposite*w_ratio +
Q26*x_ratio*y_ratio*z_opposite*w_ratio +
Q17*x_opposite*y_opposite*z_ratio*w_ratio +
Q27*x_ratio*y_opposite*z_ratio*w_ratio +
Q18*x_opposite*y_ratio*z_ratio*w_ratio +
Q28*x_ratio*y_ratio*z_ratio*w_ratio
)
return pixel_value
def resize_4d(img, new_size):
new_img = np.zeros(new_size)
for i in range(new_size[0]):
for j in range(new_size[1]):
for k in range(new_size[2]):
for l in range(new_size[3]):
x = i * (img.shape[0] - 1) / (new_size[0] - 1)
y = j * (img.shape[1] - 1) / (new_size[1] - 1)
z = k * (img.shape[2] - 1) / (new_size[2] - 1)
w = l * (img.shape[3] - 1) / (new_size[3] - 1)
new_img[i, j, k, l] = bilinear_interpolation_4d(x, y, z, w, img)
return new_img
```
其中,`img`是原始四维张量,`new_size`是目标四维张量的大小。`resize_4d`函数将原始四维张量扩大到目标大小,并返回新的四维张量。`bilinear_interpolation_4d`函数是双线性插值的具体实现函数,用于计算插值后的像素值。
阅读全文