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通过套接字发送 C++ OpenCV 图像

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我正在尝试使用 OpenCV 和套接字实现流媒体服务.服务器端加载给定的图像并将其发送到客户端，客户端通过套接字接收并显示它.但是，我在发送图像数据并在客户端重建它时遇到了很多麻烦.这是我到目前为止所做的代码:

图片发送者:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h> 
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>

using namespace cv;
using namespace std;

void error(const char *msg)
{
    perror(msg);
    exit(0);
}

int main(int argc,char *argv[])
{
    int sockfd,portno,n;
    struct sockaddr_in serv_addr;
    struct hostent *server;

    char buffer[256];
    if (argc < 3) {
       fprintf(stderr,"usage %s hostname port
",argv[0]);
       exit(0);
    }
    portno = atoi(argv[2]);
    sockfd = socket(AF_INET,SOCK_STREAM,0);
    if (sockfd < 0) 
        error("ERROR opening socket");
    server = gethostbyname(argv[1]);
    if (server == NULL) {
        fprintf(stderr,"ERROR,no such host
");
        exit(0);
    }
    bzero((char *) &serv_addr,sizeof(serv_addr));
    serv_addr.sin_family = AF_INET;
    bcopy((char *)server->h_addr,(char *)&serv_addr.sin_addr.s_addr,server->h_length);
    serv_addr.sin_port = htons(portno);
    if (connect(sockfd,(struct sockaddr *) &serv_addr,sizeof(serv_addr)) < 0) 
        error("ERROR connecting");

    Mat image;
    image = imread(argv[3],CV_LOAD_IMAGE_COLOR);
    if(! image.data )                              // Check for invalid input
    {
        cout <<  "Could not open or find the image" << std::endl ;
        return -1;
    }

    n = write(sockfd,image.data,image.total()*image.channels());
    if (n < 0) 
         error("ERROR writing to socket");
    close(sockfd);

    namedwindow( "Client",CV_WINDOW_AUTOSIZE );// Create a window for display.
    imshow( "Client",image );  
    waitKey(0);
    return 0;
}

图像接收器:

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h> 
#include <opencv2/core/core.hpp>
#include <opencv2/highgui/highgui.hpp>
#include <iostream>

using namespace cv;
using namespace std;

void error(const char *msg)
{
    perror(msg);
    exit(1);
}

int main(int argc,char *argv[])
{
     int sockfd,newsockfd,portno;
     socklen_t clilen;
     char buffer[1024];
     struct sockaddr_in serv_addr,cli_addr;
     int n;
     if (argc < 2) {
         fprintf(stderr,no port provided
");
         exit(1);
     }
     sockfd = socket(AF_INET,0);
     if (sockfd < 0) 
        error("ERROR opening socket");
     bzero((char *) &serv_addr,sizeof(serv_addr));
     portno = atoi(argv[1]);
     serv_addr.sin_family = AF_INET;
     serv_addr.sin_addr.s_addr = INADDR_ANY;
     serv_addr.sin_port = htons(portno);
     if (bind(sockfd,sizeof(serv_addr)) < 0) 
              error("ERROR on binding");
     listen(sockfd,5);
     clilen = sizeof(cli_addr);
     newsockfd = accept(sockfd,(struct sockaddr *) &cli_addr,&clilen);
     if (newsockfd < 0) 
          error("ERROR on accept");
     bzero(buffer,1024);

     n = read(newsockfd,buffer,1023);
     if (n < 0) error("ERROR reading from socket");

     Mat image(690,690,CV_8UC3,*buffer);
     imwrite("/home/securitas/images/prova.jpg",image);
     close(newsockfd);
     close(sockfd);

     namedwindow( "Server",CV_WINDOW_AUTOSIZE );// Create a window for display.
     imshow( "Server",image );  
     waitKey(0);
     return 0; 
}

我在客户端收到的是一张黑色图像，没有别的.有什么帮助吗?

wanziang0723 回答：通过套接字发送 C++ OpenCV 图像

获取 Mat.data 直接发送到socket，数据顺序为 BGR BGR BGR.... 在接收端假设您知道图像的大小.接收后只需将接收到的缓冲区(BGR BGR...数组)分配给 Mat.

客户:-

Mat frame;
frame = (frame.reshape(0,1)); // to make it continuous

int  imgSize = frame.total()*frame.elemSize();

// Send data here
bytes = send(clientSock, frame.data, imgSize, 0))

服务器:-

Mat  img = Mat::zeros( height,width, CV_8UC3);
int  imgSize = img.total()*img.elemSize();
uchar sockData[imgSize];

//Receive data here

for (int i = 0; i < imgSize; i += bytes) {
    if ((bytes = recv(connectSock, sockData +i, imgSize  - i, 0)) == -1)  {
        quit("recv failed", 1);
    }
}

// Assign pixel value to img
int ptr=0;
for (int i = 0;  i < img.rows; i++) {
    for (int j = 0; j < img.cols; j++) {                                     
       img.at<cv::Vec3b>(i,j) = cv::Vec3b(sockData[ptr+ 0],sockData[ptr+1],sockData[ptr+2]);
       ptr=ptr+3;
    }
}

这篇关于通过套接字发送 C++ OpenCV 图像的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持前端之家！

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