PyQt自定义VideoWidget

谁借莪１个温暖的怀抱￠ 2022-10-07 15:50 221阅读 0赞

功能类似QVideoWidget，支持向左/向右旋转，水平/垂直翻转画面，始终保持原始长宽比不变。支持上浮透明控件（这个QVideoWidget实现不了）。  
VideoSurface.py

from PyQt5.QtCore import *
    from PyQt5.QtGui import *
    from PyQt5.QtMultimedia import *
    
    """视频接口"""
    class VideoSurface(QAbstractVideoSurface):
        showImageSignal = pyqtSignal(QImage)
    
        def __init__(self, parent=None):
            super(VideoSurface, self).__init__(parent)
    
        def supportedPixelFormats(self, type):
            return [QVideoFrame.Format_RGB32, QVideoFrame.Format_RGB32]
    
        def present(self, frame):
            """获取帧并发送信号"""
            if frame.isValid():
                cloneFrame = QVideoFrame(frame)
                cloneFrame.map(QAbstractVideoBuffer.ReadOnly)
                img = QImage(cloneFrame.bits(), cloneFrame.width(), cloneFrame.height(),
                             QVideoFrame.imageFormatFromPixelFormat(cloneFrame.pixelFormat()))
                cloneFrame.unmap()
                self.showImageSignal.emit(img)
                return True
            return False

VideoWidget.py

from PyQt5.QtWidgets import *
    from VideoSurface import *
    
    
    class VideoWidget(QWidget):
        def __init__(self, parent=None):
            super(VideoWidget, self).__init__(parent)
            # 当前帧QImage
            self.__image = None
            # 旋转的度数
            self.__degree = 0
            # 缩放后的宽度
            self.__scaleWidth = None
            # 缩放后的高度
            self.__scaleHeight = None
            # 缩放后的位置
            self.__posX = 0
            self.__posY = 0
            # 垂直翻转标志位
            self.__verticalFlipFlag = False
            # 水平翻转标志位
            self.__horizontalFlipFlag = False
    
        def resizeEvent(self, event):
            self.calculateRectAfterResize()
            if self.__degree in (-90, 90, -270, 270):
                # 交换两个变量
                self.__scaleWidth, self.__scaleHeight = self.__scaleHeight, self.__scaleWidth
            self.update()
            super(VideoWidget, self).resizeEvent(event)
    
        def paintEvent(self, event):
            painter = QPainter()
            painter.begin(self)
            if self.__image:
                rect = QRectF(self.__posX, self.__posY, self.__image.width(), self.__image.height())
                painter.drawImage(rect, self.__image)
            else:
                # 这里可以做视频加载动画
                pass
            painter.end()
    
        def calculateRectAfterResize(self):
            """调整大小后计算宽高和位置"""
            if self.__image:
                # 当前显示窗口宽高比
                widgetRatio = self.width() / self.height()
                srcRatio = self.__image.width() / self.__image.height()
                if widgetRatio >= srcRatio:
                    self.__scaleWidth = srcRatio * self.height()
                    self.__scaleHeight = self.height()
                    self.__posX = (self.width() - self.__scaleWidth) / 2
                    self.__posY = 0
                else:
                    self.__scaleWidth = self.width()
                    self.__scaleHeight = self.width() / srcRatio
                    self.__posX = 0
                    self.__posY = (self.height() - self.__scaleHeight) / 2
    
        def calculateRectAfterTransform(self):
            """setTransform后计算宽高和位置"""
            if self.__image:
                # 当前显示窗口宽高比
                widgetRatio = self.width() / self.height()
                srcRatio = self.__image.height() / self.__image.width()
                if widgetRatio >= srcRatio:
                    self.__scaleWidth = self.height()
                    self.__scaleHeight = self.height() * srcRatio
                    self.__posX = (self.width() - self.__scaleHeight) / 2
                    self.__posY = 0
                else:
                    self.__scaleWidth = self.width() / srcRatio
                    self.__scaleHeight = self.width()
                    self.__posX = 0
                    self.__posY = (self.height() - self.__scaleWidth) / 2
    
        def showImageSlot(self, img):
            """槽函数，接收图片，进行缩放和变换"""
            if self.__image is None:
                # 如果是初次接收图片，需要根据当前窗口大小计算宽高和位置
                self.__image = img
                self.calculateRectAfterResize()
                if self.__degree in (-90, 90, -270, 270):
                    # 交换两个变量
                    self.__scaleWidth, self.__scaleHeight = self.__scaleHeight, self.__scaleWidth
            self.__image = img
            # 缩放
            self.doScale()
            # 旋转
            self.doRotate()
            # 翻转
            self.doFlip()
            self.update()
    
        def doScale(self):
            """进行缩放操作"""
            if self.__scaleWidth and self.__scaleHeight:
                self.__image = self.__image.scaled(self.__scaleWidth, self.__scaleHeight)
    
        def doRotate(self):
            """进行旋转操作"""
            if self.__degree != 0:
                matrix = QTransform()
                matrix.rotate(self.__degree)
                self.__image = self.__image.transformed(matrix, Qt.FastTransformation)
    
        def doFlip(self):
            """进行翻转操作"""
            if self.__verticalFlipFlag:
                # 垂直翻转
                self.__image = self.__image.mirrored()
            elif self.__horizontalFlipFlag:
                # 水平翻转
                self.__image = self.__image.mirrored(True, False)
    
        def setFlip(self, direction):
            if direction == horizontalFlip:
                # 如果是水平垂直翻转，对应的标志位取反
                self.__horizontalFlipFlag = not self.__horizontalFlipFlag
            elif direction == verticalFlip:
                self.__verticalFlipFlag = not self.__verticalFlipFlag
            self.update()
    
        def setRotate(self, direction):
            """设置旋转角度并计算一些值"""
            if direction == rotateToLeft:
                # 如果是左右旋转，需要修改度数
                self.__degree -= 90
            elif direction == rotateToRight:
                self.__degree += 90
            # 如果旋转度数达到了+-360，归零
            if self.__degree == 360 or self.__degree == -360:
                self.__degree = 0
            self.calculateRectAfterTransform()
            if self.__degree in (0, -180, 180):
                self.__scaleWidth, self.__scaleHeight = self.__scaleHeight, self.__scaleWidth
            self.update()
    
    
    horizontalFlip = 0
    verticalFlip = 1
    rotateToLeft = 0
    rotateToRight = 1

测试类

import sys
    
    from VideoWidget import *
    
    if __name__ == '__main__':
        a = QApplication(sys.argv)
        player = QMediaPlayer()
        videoSurface = VideoSurface()
        player.setVideoOutput(videoSurface)
    
        widget = VideoWidget()
        widget.resize(500, 350)
        widget.setStyleSheet('''
            QPushButton {
                color: blue;
                background-color: rgba(0,0,0,0.5)
            }
        ''')
    
        button1 = QPushButton("向左旋转", widget)
        button1.setGeometry(0, 0, 100, 30)
        button1.clicked.connect(lambda: widget.setRotate(rotateToLeft))
    
        button2 = QPushButton("向右旋转", widget)
        button2.setGeometry(0, 150, 100, 30)
        button2.clicked.connect(lambda: widget.setRotate(rotateToRight))
    
        button3 = QPushButton("水平翻转", widget)
        button3.setGeometry(150, 0, 100, 30)
        button3.clicked.connect(lambda: widget.setFlip(horizontalFlip))
    
        button4 = QPushButton("垂直翻转", widget)
        button4.setGeometry(150, 150, 100, 30)
        button4.clicked.connect(lambda: widget.setFlip(verticalFlip))
    
        widget.show()
    
        videoSurface.showImageSignal.connect(widget.showImageSlot)
    
        player.setMedia(QMediaContent(QUrl.fromLocalFile(r'C:/Users/ngoyat/Desktop/000.mp4')))
        player.play()
        sys.exit(a.exec())

运行效果  
![在这里插入图片描述][2021061823514130.gif]

[2021061823514130.gif]: /images/20221005/36c0f9a87540417b8567155b872d9a87.png