问题
I can capture a video from the webcam and save it fine with this code
cap = cv2.VideoCapture(0)
fgbg= cv2.BackgroundSubtractorMOG()
fourcc = cv2.cv.CV_FOURCC(*'DIVX')
out = cv2.VideoWriter('output.avi', fourcc, 20.0, (640,480))
while(cap.isOpened()):
ret,frame = cap.read()
if ret:
fgmask = fgbg.apply(frame)
out.write(frame) #Save it
cv2.imshow('Background Subtraction', fgmask)
if cv2.waitKey(1) & 0xFF == ord('q'):
break #q to quit
else:
break #EOF
cap.release()
out.release()
cv2.destroyAllWindows()
This records it as one would expect, and shows the background subtraction thing also. It saves it to output.avi. All is well. But I can't save the foreground mask, it gives me a Could not demultiplex stream
error. (This line is changed in the code above).
out.write(fgmask) #Save it
Why is this? Is the fgmask not a frame like when I am reading from the capture?
回答1:
Alright figured it out! Let me know if there's a more efficient way to do this or if I am missing something..
The foreground mask generated in background subtraction is an 8bit binary image, so we have to convert it to a different format. Probably a better one exists, but I used RGB
frame = cv2.cvtColor(fgmask, cv2.COLOR_GRAY2RGB)
来源:https://stackoverflow.com/questions/28049295/how-to-save-masks-of-videos-in-opencv2-python