I'm trying to re-size the video using opencv and then save it back to my system.The code works and does not give any error but output video file is corrupted. The fourcc I am using is mp4v works well with .mp4 but still the output video is corrupted. Need Help.
import numpy as np
import cv2
import sys
import re
vid=""
if len(sys.argv)==3:
vid=sys.argv[1]
compress=int(sys.argv[2])
else:
print("File not mentioned or compression not given")
exit()
if re.search('.mp4',vid):
print("Loading")
else:
exit()
cap = cv2.VideoCapture(0)
ret, frame = cap.read()
def rescale_frame(frame, percent=75):
width = int(frame.shape[1] * percent/ 100)
height = int(frame.shape[0] * percent/ 100)
dim = (width, height)
return cv2.resize(frame, dim, interpolation =cv2.INTER_AREA)
FPS= 15.0
FrameSize=(frame.shape[1], frame.shape[0])
fourcc = cv2.VideoWriter_fourcc(*'mp4v')
out = cv2.VideoWriter('Video_output.mp4', fourcc, FPS, FrameSize, 0)
while(cap.isOpened()):
ret, frame = cap.read()
# check for successfulness of cap.read()
if not ret: break
rescaled_frame=rescale_frame(frame,percent=compress)
# Save the video
out.write(rescaled_frame)
cv2.imshow('frame',rescaled_frame)
if cv2.waitKey(1) & 0xFF == ord('q'):
break
cap.release()
out.release()
cv2.destroyAllWindows()
The problem is the
VideoWriter
initialization.You initialized:
The last parameter
0
means,isColor = False
. You are telling, you are going to convert frames to the grayscale and then saves. But there is no conversion in your code.Also, you are resizing each frame in your code based on
compress
parameter.If I use the default compress parameter:
Now we have initialized the
VideoWriter
with the desired dimension.Full Code:
Possible Question: I don't want to change my
VideoWriter
parameters, what should I do?Answer: Then you need to change your frames, to the gray image: