Question

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我简化了原始查询，因为大多数人都不理解。

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嗨，我想使用OpenCV全屏显示视频但不确定如何。这是我的代码到目前为止，是的我是一个新手，但你必须从某个地方开始。我正在运行Python 3.6.3

问题：如何使用OpenCV全屏显示视频？

import cv2
import numpy as np
import os
os.environ['SDL_VIDEO_CENTERED'] = '1'
cap = cv2.VideoCapture("video.mp4")
cv2.namedWindow("window", cv2.WND_PROP_FULLSCREEN)
cv2.setWindowProperty("video.mp4",cv2.WND_PROP_FULLSCREEN,cv2.WINDOW_FULLSCREEN)
while(cap.isOpened()):
  ret, frame = cap.read()
  if ret == True:
    cv2.imshow('Frame',frame)
    if cv2.waitKey(30) & 0xFF == ord('q'):
      break
  else:
    break
cap.release()
cv2.destroyAllWindows()

我也收到此错误

追踪（最近一次通话）：文件“C：/Users/A/Desktop/vid.py”，第7行，in cv2.setWindowProperty（ “video.mp4”，cv2.WND_PROP_FULLSCREEN，cv2.WINDOW_FULLSCREEN） cv2.error：C：\ projects \ opencv-python \ opencv \ modules \ highgui \ src \ window_w32.cpp：443：错误：（ - 27）函数cvSetModeWindow_W32中的NULL窗口

Answer 1

感谢Dan Masek，我的orignial问题的答案是：

import cv2
import numpy as np

file_name = "video location here"
window_name = "window"
interframe_wait_ms = 30

cap = cv2.VideoCapture(file_name)
if not cap.isOpened():
    print("Error: Could not open video.")
    exit()

cv2.namedWindow(window_name, cv2.WND_PROP_FULLSCREEN)
cv2.setWindowProperty(window_name, cv2.WND_PROP_FULLSCREEN, cv2.WINDOW_FULLSCREEN)

while (True):
    ret, frame = cap.read()
    if not ret:
        print("Reached end of video, exiting.")
        break

    cv2.imshow(window_name, frame)
    if cv2.waitKey(interframe_wait_ms) & 0x7F == ord('q'):
        print("Exit requested.")
        break

cap.release()
cv2.destroyAllWindows()

Pastebin

Answer 2

我不明白你的问题但是如果你想打开摄像机你可以尝试这个代码：

import numpy as np
import cv2

cap = cv2.VideoCapture(0)

# Define the codec and create VideoWriter object
fourcc = cv2.VideoWriter_fourcc(*'XVID')
out = cv2.VideoWriter('output.avi',fourcc, 20.0, (640,480))

while(cap.isOpened()):
    ret, frame = cap.read()
    if ret:
        gray = cv2.cvtColor(src=frame, code=cv2.COLOR_BGR2GRAY)

        out.write(gray)

        cv2.imshow('frame', gray)
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    else:
        break

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

Answer 3

while(cap.isOpened()):
   ret, frame = cap.read()
   if ret == True:
        cv2.namedWindow("window", cv2.WND_PROP_FULLSCREEN)
        cv2.setWindowProperty("window",cv2.WND_PROP_FULLSCREEN,
               cv2.WINDOW_FULLSCREEN)
        cv2.imshow('window',frame)
        if cv2.waitKey(30) & 0xFF == ord('q'):
            break
    else:
         break

cap.release（） cv2.destroyAllWindows（）

全屏显示OpenCV上的视频

3 个答案: