waitKey(delay=…)
namedWindow(winname, flags: int = …)
destroyWindow(winname)
destroyAllWindows()
resizeWindow(winname, width, height)
# 示例代码
cv2.namedWindow('image',cv2.WINDOW_NORMAL)
cv2.imshow('image',img)
cv2.waitKey(0)
cv2.destroyAllWindows()
imread(filename: str, flags: int = …)
# 读取图像
img1 = cv2.imread('./opencv/images/1.jpg', cv2.IMREAD_COLOR) # 彩色
img2 = cv2.imread('./opencv/images/1.jpg', cv2.IMREAD_GRAYSCALE) # 灰度
imwrite(filename: str, img: Mat, params: typing.List[int] = …)
# 写入文件
cv2.imwrite('./opencv/images/1-out.jpg', img1)
cv2.imwrite('./opencv/images/2-out.jpg', img2)
imshow(winname, mat)
cv2.imshow('img', img)
matplotlib显示彩色图片
import numpy as np
import cv2
from matplotlib import pyplot as plt
if __name__ == "__main__":
img = cv2.imread('./opencv/images/1.jpg', cv2.IMREAD_COLOR)
img2 = cv2.cvtColor(img, cv2.COLOR_BGR2RGB) # BGR转RGB
plt.imshow(img2)
plt.xticks([]), plt.yticks([]) # 隐藏X,Y轴数值显示
plt.show()
matplotlib显示灰度图片
import numpy as np
import cv2
from matplotlib import pyplot as plt
if __name__ == "__main__":
img = cv2.imread('./resource/image/1.jpg', cv2.IMREAD_GRAYSCALE)
plt.imshow(img, cmap='gray', interpolation='bicubic')
plt.xticks([]),plt.yticks([]) # to hide tick values on X and Y axis
plt.show()
VideoWriter_fourcc(c1, c2, c3, c4)
line(img: Mat, pt1, pt2, color, thickness=…, lineType=…, shift=…)
rectangle(img: Mat, pt1, pt2, color, thickness=…, lineType=…, shift=…)
circle(img: Mat, center, radius, color, thickness=…, lineType=…, shift=…)
ellipse(img: Mat, center, axes, angle, startAngle, endAngle, color, thickness=…, lineType=…, shift=…)
polylines(img: Mat, pts, isClosed, color, thickness=…, lineType=…, shift=…)
putText(img: Mat, text, org, fontFace, fontScale, color, thickness=…, lineType=…, bottomLeftOrigin=…)