学习笔记之——将图片保存为视频

将视频转换为图片这是大家都熟知的操作，本博文介绍一下将图片转换为视频。下面直接给出代码

#include <ros/ros.h>
#include <iostream> 
#include <opencv2/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <opencv2/imgproc/imgproc.hpp>
#include <image_transport/image_transport.h>
#include <cv_bridge/cv_bridge.h>
#include <opencv2/opencv.hpp>
#include <sstream>
#include <stdlib.h>
#include <stdio.h>
#include <cv.h>
#include "std_msgs/String.h"

using namespace std;
using namespace cv;

cv::Mat img;
int i=0;
char image_name[30];
int isColor = 1;
int frame_fps =60;
int frame_width = 640;
int frame_height = 480;
string video_name = "out.avi";
cv::VideoWriter writer = VideoWriter(video_name, CV_FOURCC('X', 'V', 'I', 'D'),frame_fps,Size(frame_width,frame_height),isColor);
//cv::namedWindow("image to video", CV_WINDOW_AUTOSIZE);

class IMAGE_LISTENER_and_LOCATOR {
private:
    ros::NodeHandle nh_;  // 定义ROS句柄
    image_transport::ImageTransport it_;  // 定义一个image_transport实例
    image_transport::Subscriber image_sub_;  // 定义ROS图象接收器

public:
    IMAGE_LISTENER_and_LOCATOR()
    :it_(nh_) {   // 构造函数
        // 定义图象接受器，订阅话题是“camera/image”
        image_sub_ = it_.subscribe("camera/image", 1, &IMAGE_LISTENER_and_LOCATOR::convert_callback, this);
        // 初始化输入输出窗口
        // cv::namedWindow(INPUT);
        // cv::namedWindow(OUTPUT);
    }
    ~IMAGE_LISTENER_and_LOCATOR() {  // 析构函数
        // cv::destroyWindow(INPUT);
        // cv::destroyWindow(OUTPUT);
    }

    void convert_callback(const sensor_msgs::ImageConstPtr& msg)
    {  
      cv_bridge::CvImagePtr cv_ptr;  // 声明一个CvImage指针的实例
      try {
        // 将ROS消息中的图象信息提取，生成新cv类型的图象，复制给CvImage指针
        cv_ptr =  cv_bridge::toCvCopy(msg, sensor_msgs::image_encodings::MONO8);
      }
      catch(cv_bridge::Exception& e) {  // 异常处理
        ROS_ERROR("cv_bridge exception: %s", e.what());
        return;
      }
      img=cv_ptr->image;
      sprintf(image_name, "%s%d%s", "/home/song/img/image", ++i, ".jpg");
      //resize(img,img,Size(1536,2048));
      //imshow("image to video",img);
      if (!img.data)//判断图片调入是否成功
		  {
        cout<< "Could not load image file...\n" << endl;
		  }
      cv::imwrite(image_name,img);
      img = imread(image_name);
      //images.push_back(img);
      writer.write(img);
    }
    
};

int main(int argc, char **argv)
{
  ros::init(argc, argv, "Get_vedio");
  IMAGE_LISTENER_and_LOCATOR obj;
  ros::spin();
  return 0;
}