（17）Python读取摄像头并实现视频播放、暂停、指定目录保存、回放功能

读取摄像头并播放、暂停功能

1. import sys
2. #import scipy.io as sio
3. from PyQt5 import QtGui, QtCore, QtWidgets
4. #from wyc import Ui_Form
5. import cv2
6. import numpy as np
7. class VideoCapture(QtWidgets.QWidget):
8. def __init__(self, filename, parent):
9. super(QtWidgets.QWidget, self).__init__()
10. self.cap = cv2.VideoCapture(0)
11. self.video_frame = QtWidgets.QLabel()
12. parent.layout.addWidget(self.video_frame)
13. def nextFrameSlot(self):
14. ret, frame = self.cap.read()
15. # frame = cv2.cvtColor(frame, cv2.cv.CV_BGR2RGB)
16. frame2 = np.zeros((frame.shape), dtype=np.int8)
17. # BGR
18. frame2[:, :, 0] = frame[:, :, 2]
19. frame2[:, :, 1] = frame[:, :, 1]
20. frame2[:, :, 2] = frame[:, :, 0]
21. img = QtGui.QImage(frame2, frame2.shape[1], frame2.shape[0], QtGui.QImage.Format_RGB888)
22. pix = QtGui.QPixmap.fromImage(img)
23. self.video_frame.setPixmap(pix)
24. def start(self):
25. self.timer = QtCore.QTimer()
26. self.timer.timeout.connect(self.nextFrameSlot)
27. self.timer.start(1000.0/30)
28. def pause(self):
29. self.timer.stop()
30. def deleteLater(self):
31. self.cap.release()
32. super(QtGui.QWidget, self).deleteLater()
33. class VideoDisplayWidget(QtWidgets.QWidget):
34. def __init__(self,parent):
35. super(VideoDisplayWidget, self).__init__(parent)
36. self.layout = QtWidgets.QFormLayout(self)
37. self.startButton = QtWidgets.QPushButton('播放', parent)
38. self.startButton.clicked.connect(parent.startCapture)
39. self.startButton.setFixedWidth(50)
40. self.pauseButton = QtWidgets.QPushButton('暂停', parent)
41. self.pauseButton.setFixedWidth(50)
42. self.layout.addRow(self.startButton, self.pauseButton)
43. self.setLayout(self.layout)
44. class ControlWindow(QtWidgets.QMainWindow):
45. def __init__(self):
46. super(ControlWindow, self).__init__()
47. self.setGeometry(100, 100, 800, 600)
48. self.setWindowTitle("视频显示demo")
49. self.capture = None
50. self.matPosFileName = None
51. self.videoFileName = None
52. self.positionData = None
53. self.updatedPositionData = {'red_x':[], 'red_y':[], 'green_x':[], 'green_y': [], 'distance': []}
54. self.updatedMatPosFileName = None
55. self.isVideoFileLoaded = True
56. self.isPositionFileLoaded = True
57. self.quitAction = QtWidgets.QAction("&Exit", self)
58. self.quitAction.setShortcut("Ctrl+Q")
59. self.quitAction.setStatusTip('Close The App')
60. self.quitAction.triggered.connect(self.closeApplication)
61. # self.openMatFile = QtWidgets.QAction("&Open Position File", self)
62. # self.openMatFile.setShortcut("Ctrl+Shift+T")
63. # self.openMatFile.setStatusTip('Open .mat File')
64. # self.openMatFile.triggered.connect(self.loadPosMatFile)
65. # self.openVideoFile = QtWidgets.QAction("&Open Video File", self)
66. # self.openVideoFile.setShortcut("Ctrl+Shift+V")
67. # self.openVideoFile.setStatusTip('Open .h264 File')
68. # self.openVideoFile.triggered.connect(self.loadVideoFile)
69. # self.mainMenu = self.menuBar()
70. # self.fileMenu = self.mainMenu.addMenu('&File')
71. # self.fileMenu.addAction(self.openMatFile)
72. # self.fileMenu.addAction(self.openVideoFile)
73. # self.fileMenu.addAction(self.quitAction)
74. self.videoDisplayWidget = VideoDisplayWidget(self)
75. self.setCentralWidget(self.videoDisplayWidget)
76. def startCapture(self):
77. if not self.capture and self.isPositionFileLoaded and self.isVideoFileLoaded:
78. self.capture = VideoCapture(self.videoFileName, self.videoDisplayWidget)
79. self.videoDisplayWidget.pauseButton.clicked.connect(self.capture.pause)
80. self.capture.start()
81. def endCapture(self):
82. self.capture.deleteLater()
83. self.capture = None
84. # def loadPosMatFile(self):
85. # try:
86. # self.matPosFileName = str(QtGui.QFileDialog.getOpenFileName(self, 'Select .mat position File'))
87. # self.positionData = sio.loadmat(self.matPosFileName)
88. # self.isPositionFileLoaded = True
89. # except:
90. # print("Please select a .mat file")
91. # def loadVideoFile(self):
92. # try:
93. # self.videoFileName = QtGui.QFileDialog.getOpenFileName(self, 'Select .h264 Video File')
94. # self.isVideoFileLoaded = True
95. # except:
96. # print("Please select a .h264 file")
97. def closeApplication(self):
98. choice = QtGui.QMessageBox.question(self, 'Message','Do you really want to exit?',QtGui.QMessageBox.Yes | QtGui.QMessageBox.No)
99. if choice == QtGui.QMessageBox.Yes:
100. print("Closing....")
101. sys.exit()
102. else:
103. pass
104. if __name__ == '__main__':
105. import sys
106. app = QtWidgets.QApplication(sys.argv)
107. window = ControlWindow()
108. window.show()
109. sys.exit(app.exec_())

回放、指定目录保存功能

1. 以时间戳的形式保存视频：
2. import cv2
3. import datetime
4. cap = cv2.VideoCapture(0)
5. import os.path
6. save_path = 'G:/Temp/' #以特定前缀保存视频文件到指定目录
7. timeNow = "%s.avi" % (datetime.datetime.now().strftime('%Y_%m_%d_%H-%M-0%S'))
8. completeName = os.path.join(save_path, timeNow)
9. out = (cv2.VideoWriter(timeNow, cv2.VideoWriter_fourcc(*'PIM1'), 30.0, (640, 480))) #第三个参数是帧率
10. while cap.isOpened():
11. ret, frame = cap.read()
12. if ret==True:
13. out.write(frame)
14. cv2.imshow('frame', frame)
15. if cv2.waitKey(1) & 0xFF == ord('q'):
16. break
17. else:
18. break
19. # Release everything if job is finished
20. cap.release()
21. out.release()
22. cv2.destroyAllWindows()
23. 回放视频：
24. import os
25. def videoBack(self):
26. os.startfile("G:/Tx2Project/VideoShow") #录制的视频存放文件