cut.py 文件源码

def transform_by4(self, img, points):
        points = sorted(points, key=lambda x: x[1])
        if len(points) == 4:
            top = sorted(points[:2], key=lambda x: x[0])
            bottom = sorted(points[2:], key=lambda x: x[0], reverse=True)
            points = np.array(top + bottom, dtype='float32')
        else:
            y_min, y_max = points[0][1], points[-1][1]
            points = sorted(points, key=lambda x: x[0])
            x_min, x_max = points[0][0], points[-1][0]
            points = np.array([np.array([x_min, y_min]),
                               np.array([x_max, y_min]),
                               np.array([x_max, y_max]),
                               np.array([x_min, y_max])],
                              np.float32)

        width = max(np.sqrt(((points[0][0] - points[2][0]) ** 2) * 2),
                    np.sqrt(((points[1][0] - points[3][0]) ** 2) * 2))
        height = max(np.sqrt(((points[0][1] - points[2][1]) ** 2) * 2),
                     np.sqrt(((points[1][1] - points[3][1]) ** 2) * 2))

        dst = np.array([np.array([0, 0]),
                        np.array([width - 1, 0]),
                        np.array([width - 1, height - 1]),
                        np.array([0, height - 1]),
                        ], np.float32)

        # ??????????????????????????
        trans = cv2.getPerspectiveTransform(points, dst)
        return cv2.warpPerspective(img, trans, (int(width), int(height)))