python - 使用skimage python从图像中选择具有特定度量的区域(正方形)

Question

我正在尝试从图像(肺部图像)中提取 3 个区域，这些区域在软组织中显示，每个区域都是具有特定高度和宽度的正方形，例如宽高各10mm，如下图，

如图所示，该区域也是均匀的，这意味着它只包含相同的颜色(在这种情况下是软组织)

如何使用像 skimage 或 cv2 这样的 python 库来完成它？

Answer 1

以下代码将提取红色矩形注释内的感兴趣区域 (ROI)。根据需要调整颜色。

import requests
from io import BytesIO

import numpy as np
import scipy.ndimage as ndimage
from PIL import Image

# replace with your image loading routines
img = Image.open(BytesIO(requests.get('/image/7k5VO.png').content))
np_img = np.asarray(img)

red_parts = (np_img == (255, 0, 0, 255)).all(axis=-1)  # find red parts of RGBA image
filled_rects = ndimage.binary_fill_holes(red_parts)  # fill the rects to get a binary mask of ROI
rects_inner = filled_rects ^ red_parts  # remove the red border
labelled_rects, num_rects = ndimage.label(rects_inner)  # label/number each individual rect

ROIs = []
for i in range(1, num_rects + 1):  # 0 is background
    current_mask = labelled_rects == i
    x, y = np.where(current_mask)  # indices where current_mask is True (= area of interest)
    sub_image = np_img[x.min():x.max(), y.min():y.max()]  # extract image data inside rects
    sub_image = sub_image[1:-1, 1:-1]  # remove remaining red border (might be an image compression artefact, needs testing)
    ROIs.append(sub_image)
pil_imgs = [Image.fromarray(roi) for roi in ROIs]

这为您提供了以下标记的皮下脂肪组织图像: