如何在OpenCV中将视频分辨率更改为1440p

Question

I am trying to capture a video from webcam in 1440p but the output file cannot be opened. There aren't any problem when I captured in 1080p and 2592*1944 (5mp), only 1440p that has a problem. Does anybody knows how can I make it work with 1440p?

I am not sure is it about the fourCC but I tried changing it to DIVX and the result still the same.

import cv2

cap = cv2.VideoCapture(0)

framesize = '1440p'

if framesize=='5mp':
    cap.set(3, 2592)
    cap.set(4, 1944)
    resolution = (2592,1944)
elif framesize=='1440p':
    cap.set(3, 2560)
    cap.set(4, 1440)
    resolution = (2560, 1440)
else :
    cap.set(3, 1920)
    cap.set(4, 1080)
    resolution = (1920, 1080)

fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('new_output.avi',fourcc, 20.0, resolution)

while(cap.isOpened()):
    ret, frame = cap.read()
    if ret==True:
        out.write(frame)
        cv2.imshow('frame',frame)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    else:
        break

cap.release()
out.release()
cv2.destroyAllWindows()

The output file is only 13 KB. When trying to play it, there's a message "This file isn't playable. That might be because the file type is unsupported, the file extension is incorrect, or the file is corrupt. 0xc10100be"

Answer 1

I think you have to resize each frame before passing it to the VideoWriter() :

out = VideoWriter(outvid, fourcc, float(fps), size, is_color)
if size[0] != img.shape[1] and size[1] != img.shape[0]:
    img = resize(img, size)
out.write(img)

More examples at https://www.programcreek.com/python/example/72134/cv2.VideoWriter