[PyQt5] QGraphicsView로 웹캠 영상 스트리밍하는 데모 만들기

사각형 드래그 가능

우클릭 누르면 마지막에 그린거 삭제 됨

import sys
import cv2

from PyQt5.QtWidgets import QApplication, QMainWindow, QWidget, QPushButton, QFileDialog, QLabel, QGraphicsView, QGraphicsScene
from PyQt5.QtWidgets import QHBoxLayout, QVBoxLayout
from PyQt5.QtGui import QPixmap, QImage, QPainter, QPen, QColor, QBrush
from PyQt5.QtCore import QPointF, QRectF, Qt, QTimer


class GraphicView(QGraphicsView):
    def __init__(self, parent):
        super().__init__(parent)
        self.parent = parent
        self.scene = QGraphicsScene()        
        self.setScene(self.scene)

        self.timer = QTimer()
        self.timer.timeout.connect(self.display)

        self.items = {}
        self.items['rect'] = []

        self.start = QPointF()
        self.end = QPointF()

        self.pen = QPen(QColor(0,0,0), 3)
 
        self.setRenderHint(QPainter.HighQualityAntialiasing)

        self.timer.start()
    
    def display(self):
        _, frame = self.parent.cam.read()
        self.scene.addPixmap(self.array_to_pixmap(frame))
        self.setScene(self.scene)        

    def array_to_pixmap(self, array):
        h, w, _ = array.shape
        print(h, w)
        qimg = QImage(array.data, w, h, w*3, QImage.Format_RGB888)
        qpixmap = QPixmap(qimg)

        return qpixmap
    
    def closeEvent(self, e):
        self.timer.stop()

    def moveEvent(self, e):
        rect = QRectF(self.rect())
        rect.adjust(0,0,-2,-2)
        self.scene.setSceneRect(rect)

    def mousePressEvent(self, e):
        if e.button() == Qt.LeftButton:
            self.start = e.pos()
            self.end = e.pos()
            
            rect = QRectF(self.start, self.end)
            self.items['rect'].append(self.scene.addRect(rect, self.pen))

        if e.button() == Qt.RightButton:
            if self.scene.items():
                self.scene.removeItem(self.items['rect'][-1])
                del(self.items['rect'][-1])

    def mouseMoveEvent(self, e):  
        if e.buttons() & Qt.LeftButton:           
            self.end = e.pos()

            if self.scene.items():
                self.scene.removeItem(self.items['rect'][-1])
                del(self.items['rect'][-1])

            rect = QRectF(self.start, self.end)
            self.items['rect'].append(self.scene.addRect(rect, self.pen))
    
    def mouseReleaseEvent(self, e):
        if e.button() == Qt.LeftButton:
            if self.scene.items():
                self.scene.removeItem(self.items['rect'][-1])
                del(self.items['rect'][-1])

            rect = QRectF(self.start, self.end)
            self.items['rect'].append(self.scene.addRect(rect, self.pen))

class Demo(QMainWindow):
    def __init__(self):
        super().__init__()
        self.initCam()
        self.initUI()
    
    def initCam(self):
        self.cam = cv2.VideoCapture(0)
        if self.cam.isOpened():
            print('cam open!')

        # cam setting
        self.width = self.cam.get(cv2.CAP_PROP_FRAME_WIDTH)
        self.height = self.cam.get(cv2.CAP_PROP_FRAME_HEIGHT)
        self.width *= 2
        self.height *= 2
        self.cam.set(cv2.CAP_PROP_FRAME_WIDTH, self.width)
        self.cam.set(cv2.CAP_PROP_FRAME_HEIGHT, self.height)

    def initUI(self):
        self.view = GraphicView(self)
        self.view.setFixedSize(self.width, self.height)

        main_layout = QHBoxLayout()
        main_layout.addWidget(self.view)

        widget = QWidget(parent=self)
        widget.setLayout(main_layout)
        self.setCentralWidget(widget)

        self.setFixedSize(self.width + 100, self.height+100)
        
        self.show()

if __name__ == '__main__':
    app = QApplication(sys.argv)
    ex = Demo()
    sys.exit(app.exec_())