Python VideoCapture.isOpened方法代码示例

# 需要导入模块: from cv2 import VideoCapture [as 别名]
# 或者: from cv2.VideoCapture import isOpened [as 别名]
def caputure():
    # open Camera
    cam = VideoCapture(0)
    if not cam.isOpened():
        LOGGER.debug('FAILED to open camera!!!')
        return None

    # capture image
    for i in range(100):
        status, img = cam.read()
    if not status:
        LOGGER.debug('FAiLED to capture image!!!')
        return None

    cam.release()
    return img

# 需要导入模块: from cv2 import VideoCapture [as 别名]
# 或者: from cv2.VideoCapture import isOpened [as 别名]
class camera(object):
    '''
    Object containing camera information
    Call-able, retrieve current frame in camera buffer
    
    User accessible attributes:
        device        system device number
        resolution    camera resolution
        BGRimage      image in BGR format
        HSVimage      image in HSV format
        RGBimage      image in RGB format
        FPS           camera speed in FPS
        
    User accessible methods:
        close         close camera device
    '''
    def __init__(self, cam_num = -1, resolution = (640, 480)):
        '''
        create camera object
            cam_num            device number (integer)
            resolution         image resolution (tuple width x height)
        '''
        self.device = cam_num
        self.resolution = resolution
        self.BGRimage = []
        self.HSVimage = []
        self.RGBimage = []
        self.FPS = [0, 0]
        self.__avr = 0
        #assign and open device
        self.__capture = VideoCapture(cam_num)
        self.__capture.set(CV_CAP_PROP_FRAME_WIDTH,resolution[0])
        self.__capture.set(CV_CAP_PROP_FRAME_HEIGHT,resolution[1])
        self.__capture.open
        self.__flag = False
        t0 = time()
        self.__flag, self.BGRimage = self.__capture.read()
        self.FPS[0] = 1/(time()-t0)
        self.FPS[1] = self.FPS[0]
        self.__avr = self.FPS[0]
        print "camera", self.device, "ready @", self.FPS[0], "fps"
        return
    def __call__(self, frame_delay = 0, fast = False):
        '''
        retrieve current frame in camera buffer
            frame_delay        delay the frame decoding (integer)
            fast               if true don't decode image to RGB format (logic)    
        '''
        #set timer to meassure fps
        self.__avr = self.FPS[1]
        t0 = time()
        #try to retrieve current frame
        while not self.__flag:
            if frame_delay > 0:
                for i in xrange(frame_delay + 1):
                    self.__capture.grab()
                self.__flag, self.BGRimage = self.__capture.retrieve()
                del i
            else:
                self.__flag, self.BGRimage = self.__capture.read()
        self.__flag = False
        #decode bgr format to hsv
        self.HSVimage = cvtColor(self.BGRimage, CV_BGR2HSV)
        if fast:
            self.FPS[0] = 1/(time()-t0)
            self.FPS[1] = (self.FPS[0]+self.__avr)/2
            return
        #decode bgr format to rgb
        self.RGBimage = cvtColor(self.BGRimage, CV_BGR2RGB)
        self.FPS[0] = 1/(time()-t0)
        self.FPS[1] = (self.FPS[0]+self.__avr)/2
        return
    def __str__(self):
        '''
        return camera information;
            device number
            device resolution
            instant speed
            average speed
        '''
        tmp = "camera object @ dev "+str(self.device)+", resolution: "+str(self.resolution)
        tmp = tmp +", fps: "+str(self.FPS[0])+", Avr. fps: "+str(self.FPS[1])
        return tmp
    def __del__(self):
        '''
        when the object is deleted, it closes the device
        '''
        self.close()
        return
    def close(self):
        '''
        close device, making it available to use 
        '''
        #if the device is open then close it
        if self.__capture.isOpened():
            self.__capture.release()
            print "camera", self.device, "closed"
        return

# 需要导入模块: from cv2 import VideoCapture [as 别名]
# 或者: from cv2.VideoCapture import isOpened [as 别名]
#! /usr/bin/python

from cv2 import VideoCapture,imshow,destroyAllWindows,waitKey,pyrDown,imread,pyrUp,GaussianBlur
from glasses import _putglass_
from moustache import _putmoustache_
from itertools import count

backgroundTreshold = 35

beach = imread('manzara640.png', -1)

video_capture = VideoCapture(0)

if not video_capture.isOpened():
    exit('The Camera is not opened')

counter = count(1)

for i in range(0, 50):
    ret, background = video_capture.read()
    imshow("Video", background)
    waitKey(10)
    print "!!! Step out of the frame !!!"
    print "Background will be detected in %d seconds" % (7 - i)
ret, background = video_capture.read()
background = pyrDown(background)
#background = pyrDown(background)

while True:
    print "Iteration %d" % counter.next()

# 需要导入模块: from cv2 import VideoCapture [as 别名]
# 或者: from cv2.VideoCapture import isOpened [as 别名]
def captureTStamp(files, duration, cod,  fps=0, verbose=True):
    '''
    guarda por un tiempo en minutos (duration) el video levantado desde la
    direccion indicada en el archvo indicado. tambíen archivos con los time
    stamps de cada frame.
    
    files = [ur, saveVideoFile, saveDateFile, saveMillisecondFile]
    duration = time in mintes
    cod = codec
    fps = frames per second for video to be saved
    verbose = print messages to screen
    
    si fpscam=0 trata de llerlo de la captura. para fe hay que especificarla
    
    para opencv '2.4.9.1'
    
    Examples
    --------
    
    from cameraUtils import captureTStamp
    
    # para la FE
    duration = 1 # in minutes
    files = ['rtsp://192.168.1.48/live.sdp',
             "/home/alumno/Documentos/sebaPhDdatos/vca_test_video.avi",
             "/home/alumno/Documentos/sebaPhDdatos/vca_test_tsFrame.txt"]
    fpsCam = 12
    cod = 'XVID'
    
    captureTStamp(files, duration, cod, fps=fpsCam)
    
    # %% para la PTZ
    duration = 0.2 # in minutes
    files = ["rtsp://192.168.1.49/live.sdp",
             "/home/alumno/Documentos/sebaPhDdatos/ptz_test_video.avi",
             "/home/alumno/Documentos/sebaPhDdatos/ptz_test_tsFrame.txt"]  
    
    fpsCam = 20
    cod = 'XVID'
    
    captureTStamp(files, duration, cod, fpsCam)
    
    '''
    
    fcc = fourcc(cod[0],cod[1],cod[2],cod[3]) # Códec de video
    
    if verbose:
        print(files)
        print("Duration",duration,"minutes")
        print("fps",fps)
        print("codec",cod)
    
    # Inicializacion
    tFin = datetime.datetime.now() + datetime.timedelta(minutes=duration)
    
    ts = list()  # timestamp de la captura
    
    # abrir captura
    cap = VideoCapture(files[0])
    while not cap.isOpened():
        cap = VideoCapture(files[0])
    
    print("capture opened")
	# configurar writer
    w = int(cap.get(frame_width))
    h = int(cap.get(frame_height))
    if not fps:
        fps = cap.get(prop_fps)
    #para fe especificar los fps pq toma cualquier cosa con la propiedad
    
    out = VideoWriter(files[1], fcc, fps,( w, h), True)
    
    if verbose:
        print("capture open",cap.isOpened())
        print("frame size",w,h)
        print("output opened",out.isOpened())
    
    if not out.isOpened() or not cap.isOpened():
        out.release()
        cap.release()
        # exit function if unable to open cap or out
        return
    
    s0 = getsize(files[1]) # initial filesize before writing frame
    # Primera captura
    ret, frame = cap.read()
    if ret:
        t = datetime.datetime.now()
        ts.append(t)
        out.write(frame)
        if verbose:
            print("first frame captured")
    # Segunda captura
    ret, frame = cap.read()
    if ret:
        t = datetime.datetime.now()
        ts.append(t)
        out.write(frame)
        if verbose:
            print("second frame captured")
#.........这里部分代码省略.........