2, opencv基础api学习-视频

1, cv2.VideoCapture(args)

读取视频

args: 可以是文件名, 也可以是0,1 标识摄像头索引

2, cap.read()

从cap中读取下一帧

ret, frame = cap.read(), ret标识是否读取到,可以判断是否读取到了视频结尾, frame为读取的图片

3, cap.isOpened()

视频或者摄像头是否初始化成功

4, cap.release()

5, cap.get(propId)

来获得一些参数信息

CAP_PROP_FRAME_HEIGHT = 4 高, CAP_PROP_FRAME_WIDTH = 3 宽, CAP_PROP_FPS = 5 fps

6, cap.set(propId,value)

修改参数信息

7, 保存视频

# -*- coding: utf-8 -*-
import numpy as np
import cv2

cap = cv.VideoCapture(0)

# 从fourcc.org查
fourcc = cv.VideoWriter_fourcc(*'XVID')
out = cv.VideoWriter('output.avi',fourcc, 20.0, (640,480))

while(cap.isOpened()):
	ret, frame = cap.read()
	if ret==True:
	frame = cv.flip(frame,0)
	out.write(frame)

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


cap.release()
out.release()
cv.destroyAllWindows()