Needing some help on integration of the webcam I am getting these errors on ubuntu 15
HIGHGUI ERROR: V4L2: Unable to get property(7) - Invalid argument
HIGHGUI ERROR: V4L2: Unable to get property (5) - Invalid argument
import cv2.cv as cv #capture = cv.CaptureFromFile('cartrim.mp4') capture = cv.CaptureFromCAM(0) #-- Informations about the video -- nbFrames = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_COUNT)) fps = cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FPS) wait = int(1/fps * 1000/20) width = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_WIDTH)) height = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_HEIGHT)) #For recording #codec = cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FOURCC) #writer=cv.CreateVideoWriter("img/output.avi", int(codec), int(fps), (width,height), 1) #Create writer with same parameters #---------------------------------- prev_gray = cv.CreateImage((width,height), 8, 1) #Will hold the frame at t-1 gray = cv.CreateImage((width,height), 8, 1) # Will hold the current frame prevPyr = cv.CreateImage((height / 3, width + 8), 8, cv.CV_8UC1) #Will hold the pyr frame at t-1 currPyr = cv.CreateImage((height / 3, width + 8), 8, cv.CV_8UC1) # idem at t max_count = 500 qLevel= 0.01 minDist = 10 prev_points = [] #Points at t-1 curr_points = [] #Points at t lines=[] #To keep all the lines overtime for f in xrange( nbFrames ): frame = cv.QueryFrame(capture) #Take a frame of the video cv.CvtColor(frame, gray, cv.CV_BGR2GRAY) #Convert to gray output = cv.CloneImage(frame) prev_points = cv.GoodFeaturesToTrack(gray, None, None, max_count, qLevel, minDist) #Find points on the image #Calculate the movement using the previous and the current frame using the previous points curr_points, status, err = cv.CalcOpticalFlowPyrLK(prev_gray, gray, prevPyr, currPyr, prev_points, (10, 10), 3, (cv.CV_TERMCRIT_ITER|cv.CV_TERMCRIT_EPS,20, 0.03), 0) #If points status are ok and distance not negligible keep the point k = 0 for i in range(len(curr_points)): nb = abs( int(prev_points[i][0])-int(curr_points[i][0]) ) + abs( int(prev_points[i][1])-int(curr_points[i][1]) ) if status[i] and nb > 2 : prev_points[k] = prev_points[i] curr_points[k] = curr_points[i] k += 1 prev_points = prev_points[:k] curr_points = curr_points[:k] #At the end only interesting points are kept #Draw all the previously kept lines otherwise they would be lost the next frame for (pt1, pt2) in lines: cv.Line(frame, pt1, pt2, (255,255,255)) #Draw the lines between each points at t-1 and t for prevpoint, point in zip(prev_points,curr_points): prevpoint = (int(prevpoint[0]),int(prevpoint[1])) cv.Circle(frame, prevpoint, 25, 255) point = (int(point[0]),int(point[1])) #cv.Circle(frame, point, 3, 255) #cv.Line(frame, prevpoint, point, (255,255,255)) #lines.append((prevpoint,point)) #Append current lines to the lines list cv.Copy(gray, prev_gray) #Put the current frame prev_gray prev_points = curr_points cv.ShowImage("Object Detection", frame) #cv.WriteFrame(writer, frame) cv.WaitKey(wait)
HIGHGUI ERROR: V4L2: Unable to get property
import cv2.cv as cv #capture = cv.CaptureFromFile('cartrim.mp4') capture = cv.CaptureFromCAM(0) #-- Informations about the video -- nbFrames = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_COUNT)) fps = cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FPS) wait = int(1/fps * 1000/20) width = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_WIDTH)) height = int(cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FRAME_HEIGHT)) #For recording #codec = cv.GetCaptureProperty(capture, cv.CV_CAP_PROP_FOURCC) #writer=cv.CreateVideoWriter("img/output.avi", int(codec), int(fps), (width,height), 1) #Create writer with same parameters #---------------------------------- prev_gray = cv.CreateImage((width,height), 8, 1) #Will hold the frame at t-1 gray = cv.CreateImage((width,height), 8, 1) # Will hold the current frame prevPyr = cv.CreateImage((height / 3, width + 8), 8, cv.CV_8UC1) #Will hold the pyr frame at t-1 currPyr = cv.CreateImage((height / 3, width + 8), 8, cv.CV_8UC1) # idem at t max_count = 500 qLevel= 0.01 minDist = 10 prev_points = [] #Points at t-1 curr_points = [] #Points at t lines=[] #To keep all the lines overtime for f in xrange( nbFrames ): frame = cv.QueryFrame(capture) #Take a frame of the video cv.CvtColor(frame, gray, cv.CV_BGR2GRAY) #Convert to gray output = cv.CloneImage(frame) prev_points = cv.GoodFeaturesToTrack(gray, None, None, max_count, qLevel, minDist) #Find points on the image #Calculate the movement using the previous and the current frame using the previous points curr_points, status, err = cv.CalcOpticalFlowPyrLK(prev_gray, gray, prevPyr, currPyr, prev_points, (10, 10), 3, (cv.CV_TERMCRIT_ITER|cv.CV_TERMCRIT_EPS,20, 0.03), 0) #If points status are ok and distance not negligible keep the point k = 0 for i in range(len(curr_points)): nb = abs( int(prev_points[i][0])-int(curr_points[i][0]) ) + abs( int(prev_points[i][1])-int(curr_points[i][1]) ) if status[i] and nb > 2 : prev_points[k] = prev_points[i] curr_points[k] = curr_points[i] k += 1 prev_points = prev_points[:k] curr_points = curr_points[:k] #At the end only interesting points are kept #Draw all the previously kept lines otherwise they would be lost the next frame for (pt1, pt2) in lines: cv.Line(frame, pt1, pt2, (255,255,255)) #Draw the lines between each points at t-1 and t for prevpoint, point in zip(prev_points,curr_points): prevpoint = (int(prevpoint[0]),int(prevpoint[1])) cv.Circle(frame, prevpoint, 25, 255) point = (int(point[0]),int(point[1])) #cv.Circle(frame, point, 3, 255) #cv.Line(frame, prevpoint, point, (255,255,255)) #lines.append((prevpoint,point)) #Append current lines to the lines list cv.Copy(gray, prev_gray) #Put the current frame prev_gray prev_points = curr_points cv.ShowImage("Object Detection", frame) #cv.WriteFrame(writer, frame) cv.WaitKey(wait)
