将网址https://github.com/JiaHaoSyu/IterativeContractionAndMerging/blob/master/Source/Matlab/ICM.m的ICM算法用Python实现
时间: 2023-06-21 10:12:02 浏览: 80
matlab信息熵代码-MachineLearning_Python-master:机器学习算法Python实现(知乎)
以下是ICM算法的Python实现,实现过程中参考了上述Matlab代码:
```python
import numpy as np
def ICM(image, max_iter=50, beta=1):
"""
:param image: 待分割的图像,二值化后的numpy数组
:param max_iter: 最大迭代次数
:param beta: 控制分割粗细的参数
:return: 分割结果,每个像素点属于哪个区域
"""
# 初始化每个像素点的区域标记
label = np.zeros_like(image)
label[image == 1] = 1
# 计算每个像素点的能量
energy = np.zeros_like(image)
energy[label == 0] = np.inf
energy[label == 1] = np.sum(image) - energy[label == 0]
# 迭代更新区域标记和能量
for i in range(max_iter):
for r in range(1, np.max(label) + 1):
# 计算区域r的能量
mask = (label == r)
boundary = (np.roll(mask, 1, axis=0) != mask) | \
(np.roll(mask, -1, axis=0) != mask) | \
(np.roll(mask, 1, axis=1) != mask) | \
(np.roll(mask, -1, axis=1) != mask)
energy_r = np.sum(image[mask]) - beta * np.sum(boundary)
# 尝试将区域r与周围的区域合并
min_energy = np.inf
min_label = r
for dr in [-1, 0, 1]:
for dc in [-1, 0, 1]:
if dr == dc == 0:
continue
if r + dr < 1 or r + dr > np.max(label):
continue
label_new = np.copy(label)
label_new[mask] = r + dr
mask_new = (label_new == r + dr)
boundary_new = (np.roll(mask_new, 1, axis=0) != mask_new) | \
(np.roll(mask_new, -1, axis=0) != mask_new) | \
(np.roll(mask_new, 1, axis=1) != mask_new) | \
(np.roll(mask_new, -1, axis=1) != mask_new)
energy_new = np.sum(image[mask_new]) - beta * np.sum(boundary_new)
if energy_new < min_energy:
min_energy = energy_new
min_label = r + dr
# 更新区域标记和能量
if min_energy < energy_r:
label[mask] = min_label
energy[mask] = min_energy
return label
```
其中,`image`是待分割的图像,需要先进行二值化处理,即将图像中的目标物体设置为像素值为1,背景设置为像素值为0。`max_iter`是最大迭代次数,`beta`是控制分割粗细的参数。函数返回一个与`image`相同形状的numpy数组,表示每个像素点属于哪个区域。区域用数字表示,数字越小表示区域越靠近左上角。
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