pyqt5+opencv實現視訊播放

（pyqt5網上資料太少，一開始查到用 vlc 做視訊控制元件，走了很多彎路，後面發現 opencv 用來做視訊控制元件更方便，而且opencv 的功能更加全面）

直接貼程式碼

import time
import sys

from PyQt5.QtCore import *
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from cv2 import *


class VideoBox(QWidget):

    VIDEO_TYPE_OFFLINE = 0
    VIDEO_TYPE_REAL_TIME = 1
 


    STATUS_INIT = 0
    STATUS_PLAYING = 1
    STATUS_PAUSE = 2

    video_url = ""

    def __init__(self, video_url="", video_type=VIDEO_TYPE_OFFLINE, auto_play=False):
        QWidget.__init__(self)
        self.video_url = video_url
        self.video_type = video_type  # 0: offline  1: realTime
 

        self.auto_play = auto_play
        self.status = self.STATUS_INIT  # 0: init 1:playing 2: pause

        # 元件展示
        self.pictureLabel = QLabel()
        init_image = QPixmap("../assets/images/no_video.jpeg").scaled(self.width(), self.height())
        self.pictureLabel.setPixmap(init_image)

        self.playButton = QPushButton()
        self.playButton.setEnabled(True
 
)
        self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaPlay))
        self.playButton.clicked.connect(self.switch_video)

        control_box = QHBoxLayout()
        control_box.setContentsMargins(0, 0, 0, 0)
        control_box.addWidget(self.playButton)

        layout = QVBoxLayout()
        layout.addWidget(self.pictureLabel)
        layout.addLayout(control_box)

        self.setLayout(layout)

        # timer 設定
        self.timer = VideoTimer()
        self.timer.timeSignal.signal[str].connect(self.show_video_images)

        # video 初始設定
        self.playCapture = VideoCapture()
        if self.video_url != "":
            self.playCapture.open(self.video_url)
            fps = self.playCapture.get(CAP_PROP_FPS)
            self.timer.set_fps(fps)
            self.playCapture.release()
            if self.auto_play:
                self.switch_video()
            # self.videoWriter = VideoWriter('*.mp4', VideoWriter_fourcc('M', 'J', 'P', 'G'), self.fps, size)

    def reset(self):
        self.timer.stop()
        self.playCapture.release()
        self.status = VideoBox.STATUS_INIT
        self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaPlay))

    def show_video_images(self):
        if self.playCapture.isOpened():
            success, frame = self.playCapture.read()
            if success:
                height, width = frame.shape[:2]
                if frame.ndim == 3:
                    rgb = cvtColor(frame, COLOR_BGR2RGB)
                elif frame.ndim == 2:
                    rgb = cvtColor(frame, COLOR_GRAY2BGR)

                temp_image = QImage(rgb.flatten(), width, height, QImage.Format_RGB888)
                temp_pixmap = QPixmap.fromImage(temp_image)
                self.pictureLabel.setPixmap(temp_pixmap)
            else:
                print("read failed, no frame data")
                success, frame = self.playCapture.read()
                if not success and self.video_type is VideoBox.VIDEO_TYPE_OFFLINE:
                    print("play finished")  # 判斷本地檔案播放完畢
                    self.reset()
                    self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaStop))
                return
        else:
            print("open file or capturing device error, init again")
            self.reset()

    def switch_video(self):
        if self.video_url == "" or self.video_url is None:
            return
        if self.status is VideoBox.STATUS_INIT:
            self.playCapture.open(self.video_url)
            self.timer.start()
            self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaPause))
        elif self.status is VideoBox.STATUS_PLAYING:
            self.timer.stop()
            if self.video_type is VideoBox.VIDEO_TYPE_REAL_TIME:
                self.playCapture.release()
            self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaPlay))
        elif self.status is VideoBox.STATUS_PAUSE:
            if self.video_type is VideoBox.VIDEO_TYPE_REAL_TIME:
                self.playCapture.open(self.video_url)
            self.timer.start()
            self.playButton.setIcon(self.style().standardIcon(QStyle.SP_MediaPause))

        self.status = (VideoBox.STATUS_PLAYING,
                       VideoBox.STATUS_PAUSE,
                       VideoBox.STATUS_PLAYING)[self.status]


class Communicate(QObject):

    signal = pyqtSignal(str)


class VideoTimer(QThread):

    def __init__(self, frequent=20):
        QThread.__init__(self)
        self.stopped = False
        self.frequent = frequent
        self.timeSignal = Communicate()
        self.mutex = QMutex()

    def run(self):
        with QMutexLocker(self.mutex):
            self.stopped = False
        while True:
            if self.stopped:
                return
            self.timeSignal.signal.emit("1")
            time.sleep(1 / self.frequent)

    def stop(self):
        with QMutexLocker(self.mutex):
            self.stopped = True

    def is_stopped(self):
        with QMutexLocker(self.mutex):
            return self.stopped

    def set_fps(self, fps):
        self.frequent = fps


if __name__ == "__main__":
   app = QApplication(sys.argv)
   box = VideoBox("home.mp4")
   box.show()
   sys.exit(app.exec_())

通過timer根據幀率不停的觸發 show_video_images 方法， 讀取到每一幀資料，將其展示在QLabel中。

本程式碼支援實時流，本地視訊 和 遠端視訊檔案，如需要測試實時流的播放，將視訊 video_url 替換為：

rtmp://live.hkstv.hk.lxdns.com/live/hks