Python学习记录(六)：opencv-python

一、安装

pip install opencv-python

二、图像读写

• cv2.imread(path, flag) 返回值类型：np.ndarray
• cv2.imwrite(filename, image)

三、图像编辑

• cv2.resize() 图像缩放，默认方式为cv2.INTER_LINEAR（双线性插值）
• cv2.flip() 图像翻转
• cv2.rotate() 图像旋转

四、常用绘图

• cv2.rectangle(image, start_point, end_point, color, thickness) start_point: 左上，end_point：右下
• cv2.circle(image, center_coordinates, radius, color, thickness) center_coordinates：中心点，radius：半径；The coordinates are represented as tuples of two values i.e. (X coordinate value, Y coordinate value)
• cv2.putText(image, text, org, font, fontScale, color[, thickness[, lineType[, bottomLeftOrigin]]])
• cv2.line(image, start_point, end_point, color, thickness)
• cv2.arrowedLine(image, start_point, end_point, color, thickness)
• cv2.polylines(image, [pts], isClosed, color, thickness) 用于在图像上绘制多边形；参数isClosed: Flag indicating whether the drawn polylines are closed or not. If they are closed, the function draws a line from the last vertex of each curve to its first vertex.（即所绘制的多边形是否闭合）

五、视频读写

• cv2.VideoCapture()
• cv2.VideoWriter(filename, fourcc, fps, frameSize)

参考链接

• cv2.rectangle()
• cv2.circle()
• cv2.putText()
• cv2.line()
• cv2.arrowedLine()
• cv2.polylines()
• cv2.VideoCapture()
• cv.VideoWriter()
• cv2.resize()
• cv2.flip()
• cv2.rotate()