图像标注版本2-多标注框

from PyQt5.QtWidgets import QWidget, QApplication, QLabel
from PyQt5.QtCore import QRect, Qt
from PyQt5.QtGui import QPixmap, QPainter, QPen
import sys

# 重定义QLabel，实现绘制事件和各类鼠标事件
class MyLabel(QLabel):
    def __init__(self, parent=None):
        '''
        :param parent:
        初始化基本参数
        '''
        super(MyLabel, self).__init__(parent)
        self.x0 = 0
        self.y0 = 0
        self.x1 = 0
        self.y1 = 0
        self.rect = QRect()
        self.flag = False
        # 增加一个存储标注框坐标的列表
        self.bboxList=[]

# 单击鼠标触发事件
# 获取鼠标事件的开始位置
def mousePressEvent(self, event):
    # 将绘制标志设置为True
    self.flag = True
    self.x0 = event.pos().x()
    self.y0 = event.pos().y()

# 鼠标移动事件
# 绘制鼠标行进过程中的矩形框
def mouseMoveEvent(self, event):
    if self.flag:
        self.x1 = event.pos().x()
        self.y1 = event.pos().y()
        self.update()

    # 鼠标释放事件
    def mouseReleaseEvent(self, event):
        # 将绘制标志设置为False
        self.flag = False
        self.x1 = event.pos().x()
        self.y1 = event.pos().y()
        # 将标注框的四个坐标轴存储到bboxList
        self.saveBBbox(self.x0,self.y0,self.x1,self.y1)

    # 绘制事件
    def paintEvent(self, event):
        super().paintEvent(event)
        painter = QPainter()
        # 增加绘制开始和结束时间
        painter.begin(self)
        # 遍历之前存储的标注框坐标列表
        for point in self.bboxList:
            rect = QRect(point[0], point[1], abs(point[0]-point[2]), abs(point[1]-point[3]))
            painter.setPen(QPen(Qt.red, 2, Qt.SolidLine))
            painter.drawRect(rect)
        # 绘制当前标注框的举行
        # 构造矩形框的起始坐标和宽度、高度
        tempx0 = min(self.x0, self.x1)
        tempy0 = min(self.y0, self.y1)
        tempx1 = max(self.x0, self.x1)
        tempy1 = max(self.y0, self.y1)
        width=tempx1-tempx0
        height=tempy1-tempy0
        currect = QRect(tempx0, tempy0, width, height)
        # 构造QPainter，进行矩形框绘制
        painter.setPen(QPen(Qt.blue, 1, Qt.SolidLine))
        painter.drawRect(currect)
        painter.end()

    # 保存到bbox列表
    def saveBBbox(self,x0,y0,x1,y1):
        tempx0 = min(x0, x1)
        tempy0 = min(y0, y1)
        tempx1 = max(x0, x1)
        tempy1 = max(y0, y1)
        bbox = (tempx0, tempy0, tempx1, tempy1)
        self.bboxList.append(bbox)

# 测试类
class LabelV2(QWidget):
    def __init__(self):
        super(LabelV2, self).__init__()
        self.initUI()

    def initUI(self):
        self.resize(960, 540)
        self.move(100, 50)
        self.setWindowTitle('Label标注框2.0版本')
        # 加载重定义的label
        self.lbl = MyLabel(self)
        # 构造QPixmap，加载待标注图片
        img = QPixmap('010.png')
        # 在自定义label中显示QImage
        self.lbl.setPixmap(img)
        self.lbl.setCursor(Qt.CrossCursor)
        self.show()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    labelwin = LabelV2()
    sys.exit(app.exec())