我想找到变换矩阵H,这样我就可以乘以(x,y)像素坐标并获得(x,y)真实世界坐标。这是我的代码:Opencv单应性从像素xy坐标找到全局xy坐标
import cv2
import numpy as np
from numpy.linalg import inv
if __name__ == '__main__' :
D=[159.1,34.2]
I=[497.3,37.5]
G=[639.3,479.7]
A=[0,478.2]
# Read source image.
im_src = cv2.imread('/home/vivek/june_14.png')
# Four corners of the book in source image
pts_src = np.array([D,I,G,A])
# Read destination image.
im_dst = cv2.imread('/home/vivek/june_14.png')
# Four corners of the book in destination image.
print "img1 shape:",im_dst.shape
scale=1
O=[0.0,0.0]
X=[134.0*scale,0]
Y=[0.0,184.0*scale]
P=[134.0*scale,184.0*scale]
# lx = 75.5 * scale
# ly = 154.0 * scale
pts_dst = np.array([O,X,P,Y])
# Calculate Homography
h, status = cv2.findHomography(pts_src, pts_dst)
print "homography:",h
print "inv of H:",inv(h)
print "position of the blob on the ground xy plane:",np.dot(np.dot(h,np.array([[323.0],[120.0],[1.0]])),scale)
# Warp source image to destination based on homography
im_out = cv2.warpPerspective(im_src, h, (im_dst.shape[1],im_dst.shape[0]))
# Display images
cv2.imshow("Source Image", im_src)
cv2.imshow("Destination Image", im_dst)
cv2.imshow("Warped Source Image", im_out)
cv2.imwrite("im_out.jpg", im_out)
cv2.waitKey(0)
我得到的全球xy是非常关闭。我在某处做错了什么?
对不起,但是变量'D,I,G,A,O,X,P,Y'是什么?这些应该代表什么?无论如何,在你计算“真实世界”(x,y)坐标的地方,你将得到*均匀*点,它们在缩放时是等价的 - 换句话说,它们可以被缩放并且仍然会被考虑同样的观点。但是你需要'x,y'点,而不是缩放的点,所以你需要按比例分割。三矢量全部按照相同的量进行缩放,因此您可以使用缩放因子的最后一个条目。你应该做'pts = scale * np.dot(h,np.array([[323.0],[120.0],[1.0]]))'然后'pts = pts/pts [-1]'。 –
OXPY是真实的单词点(O原点,右侧X-134英寸,右侧P-134英寸,向下184英寸,Y-184英寸)和DIGA是图像平面上的相应像素坐标。 –
对不起。我没有得到比例缩放部分。 –