如何确定图像的角度以检查图像是垂直的还是水平的？

Question

我正在尝试将所有图像垂直/水平对齐。我使用以下代码旋转图像：

import cv2
import imutils
import numpy as np
def rotate_bound(image, angle):
    # grab the dimensions of the image and then determine the
    # center
    (h, w) = image.shape[:2]
    (cX, cY) = (w // 2, h // 2)
    # grab the rotation matrix (applying the negative of the
    # angle to rotate clockwise), then grab the sine and cosine
    # (i.e., the rotation components of the matrix)
    M = cv2.getRotationMatrix2D((cX, cY), -angle, 1.0)
    cos = np.abs(M[0, 0])
    sin = np.abs(M[0, 1])
    # compute the new bounding dimensions of the image
    nW = int((h * sin) + (w * cos))
    nH = int((h * cos) + (w * sin))
    # adjust the rotation matrix to take into account translation
    M[0, 2] += (nW / 2) - cX
    M[1, 2] += (nH / 2) - cY
    # perform the actual rotation and return the image
    return cv2.warpAffine(image, M, (nW, nH))
image = cv2.imread("10247.png")
# loop over the rotation angles again, this time ensuring
# no part of the image is cut off
dim=(600,400)
im=rotate_bound(image,30)
im = cv2.resize(im, dim, interpolation = cv2.INTER_AREA)
cv2.imshow("Rotated (Correct)", im)

cv2.waitKey(0)
cv2.destroyWindow("Rotated (Correct)")
for angle in np.arange(0, 360, 15):
    rotated = imutils.rotate_bound(image, angle)
    dim=(800,600)
    resized = cv2.resize(rotated, dim, interpolation = cv2.INTER_AREA)
    cv2.imshow("Rotated (Correct)", resized)
    cv2.waitKey(0)
    cv2.destroyWindow("Rotated (Correct)")

我希望在图像垂直/水平时停止旋转。我该怎么阻止它？如何确定当前角度

Answer 1

你可以介绍一些AI using MediaPipe。从那里你可以看到手指的地标并旋转，例如食指向上

类似的操作可以是将图像转换为黑白，并使用morphological operation腐蚀将手臂缩小到仅线条

然后使用Hough线变换获取手指，对它们进行排序（从左到右），获取食指垂直方向的角度并旋转