视觉SLAM十四讲：从理论到实践（Chapter6：非线性优化）

opencv调用摄像头保存视频

文章目录

• opencv调用摄像头保存视频
• • 保存视频（采用默认分辨率640 x 480)
  • 保存视频（指定分辨率，例1280×720)

保存视频（采用默认分辨率640 x 480)

import cv2
import time
# 定义视频捕捉对象
cap = cv2.VideoCapture(1)  # 参数0代表计算机的默认摄像头
 
# 获取视频的宽度和高度
frame_width = int(cap.get(3))
frame_height = int(cap.get(4))
# 定义VideoWriter对象并初始
out = cv2.VideoWriter('C:/Users/Desktop/0527.mp4',cv2.VideoWriter_fourcc(*'mp4v'), 20.0, (frame_width, frame_height))

while(cap.isOpened()):
    ret, frame = cap.read()  # 读取
    if ret:
        cv2.imshow('frame', frame)       
        # 写入帧到输出视频文件
        out.write(frame)           
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    else:
        break 
# 释放资源
cap.release()
out.release()
cv2.destroyAllWindows()

保存视频（指定分辨率，例1280×720)

初始化与保存帧大小一致

import cv2
import time
# 定义视频捕捉对象
cap = cv2.VideoCapture(1)  # 参数0代表计算机的默认摄像头
 
# 获取视频的宽度和高度
frame_width = 1280
frame_height =720
# 定义VideoWriter对象并初始
out = cv2.VideoWriter('C:/Users/Desktop/0527.mp4',cv2.VideoWriter_fourcc(*'mp4v'), 20.0, (frame_width, frame_height))

while(cap.isOpened()):
    ret, frame = cap.read()  # 读取
    if ret:
        frame_resize=cv2.resize(frame,(1280,720))
        cv2.imshow('frame', frame)       
        # 写入帧到输出视频文件
        out.write(frame_resize)           
        if cv2.waitKey(1) & 0xFF == ord('q'):
            break
    else:
        break 
# 释放资源
cap.release()
out.release()
cv2.destroyAllWindows()