python – 如何使MRI图像居中

我在MRI上工作.问题是图像并不总是居中.此外,患者身体周围通常有黑带.

我希望能够移除黑色边框并使患者的身体居中,如下所示：

我已经尝试通过读取像素表来确定患者身体的边缘,但我还没有提出任何非常确定的结论.

事实上,我的解决方案仅适用于50％的图像…我没有看到任何其他方法来做到这一点……

开发环境：python3.7 OpenCV3.4

解决方法

我不确定这是执行此操作的标准或最有效的方法,但它似乎有效：

# Load image as grayscale (since it's b&w to start with)
im = cv2.imread('im.jpg',cv2.IMREAD_GRAYSCALE)

# Threshold it. I tried a few pixel values,and got something reasonable at min = 5
_,thresh = cv2.threshold(im,5,255,cv2.THRESH_BINARY)

# Find contours:
im2,contours,hierarchy = cv2.findContours(thresh,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)

# Put all contours together and reshape to (_,2).
# The first "column" will be your x values of your contours,and second will be y values
c = np.vstack(contours).reshape(-1,2)

# Extract the most left,most right,uppermost and lowermost point
xmin = np.min(c[:,0])
ymin = np.min(c[:,1])
xmax = np.max(c[:,0])
ymax = np.max(c[:,1])

# Use those as a guide of where to crop your image
crop = im[ymin:ymax,xmin:xmax]

cv2.imwrite('cropped.jpg',crop)

你到底得到的是：