在目标检测中，图像标注一般是4个顶点坐标或者是bbox的中心坐标、宽高和旋转角度，在特定的处理函数中会用到不同的标注方法，这时就需要对坐标进行转换，具体方法如下
# -*- coding: utf-8 -*- from __future__ import absolute_import from __future__ import division from __future__ import print_function import cv2 import numpy as np def forward_convert(coordinate, with_label=True): """ :param coordinate: format [y_c, x_c, h, w, theta] :return: format [y1, x1, y2, x2, y3, x3, y4, x4] """ boxes = [] if with_label: for rect in coordinate: box = cv2.boxPoints(((rect[1], rect[0]), (rect[3], rect[2]), rect[4])) box = np.reshape(box, [-1, ]) boxes.append([box[1], box[0], box[3], box[2], box[5], box[4], box[7], box[6], rect[5]]) else: for rect in coordinate: box = cv2.boxPoints(((rect[1], rect[0]), (rect[3], rect[2]), rect[4])) box = np.reshape(box, [-1, ]) boxes.append([box[1], box[0], box[3], box[2], box[5], box[4], box[7], box[6]]) return np.array(boxes, dtype=np.float32) def back_forward_convert(coordinate, with_label=True): """ :param coordinate: format [x1, y1, x2, y2, x3, y3, x4, y4, (label)] :param with_label: default True :return: format [y_c, x_c, h, w, theta, (label)] """ boxes = [] if with_label: for rect in coordinate: box = np.int0(rect[:-1]) box = box.reshape([4, 2]) rect1 = cv2.minAreaRect(box) x, y, w, h, theta = rect1[0][0], rect1[0][1], rect1[1][0], rect1[1][1], rect1[2] boxes.append([y, x, h, w, theta, rect[-1]]) else: for rect in coordinate: box = np.int0(rect) box = box.reshape([4, 2]) rect1 = cv2.minAreaRect(box) x, y, w, h, theta = rect1[0][0], rect1[0][1], rect1[1][0], rect1[1][1], rect1[2] boxes.append([y, x, h, w, theta]) return np.array(boxes, dtype=np.float32) if __name__ == '__main__': coord = np.array([[150, 150, 50, 100, -90, 1], [150, 150, 100, 50, -90, 1], [150, 150, 50, 100, -45, 1], [150, 150, 100, 50, -45, 1]]) coord1 = np.array([[150, 150, 100, 50, 0], [150, 150, 100, 50, -90], [150, 150, 100, 50, 45], [150, 150, 100, 50, -45]]) # coord2 = forward_convert(coord) #coord3 = forward_convert(coord1, mode=-1) #print(coord2) # print(coord3-coord2) coord_label = np.array([[167., 203., 96., 132., 132., 96., 203., 167., 1.]]) # coord4 = back_forward_convert(coord_label, with_label=1) coord5 = back_forward_convert(coord_label) print(coord4) # print(coord5) # coord3 = coordinate_present_convert(coord, -1) # print(coord3) # coord4 = coordinate_present_convert(coord3, mode=1) # print(coord4) 文章来源: OpenCV-坐标转换