Revision history [back]

I am trying to capture frames from a Logitech HD cam connected to a Raspberry Pi through usb, the RP is running arch linux and I am using OpenCV C api and a TCP client.

The TCP server is running c++(QT) under ubuntu.

here is my client.c code

#include <opencv/cv.h>
 #include <opencv/highgui.h>
 #include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <netdb.h>


void error(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[999999];

    if(argc <3)
    {
        fprintf(stderr,"usage %s hostname portname port\n",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\n");
        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,&serv_addr,sizeof(serv_addr)) < 0)
    {
        error("ERROR CONNECTING");
    }
    CvCapture *capture = cvCaptureFromCAM(1);
       // capture from cam
        int i =1;

       while ( 1 ) {
         // Get one frame
         IplImage* frame = cvQueryFrame( capture );
         if ( !frame ) {
           //fprintf( stderr, "ERROR: frame is null...\n" );
           getchar();
           break;
         }else
         {
             i++;
         }
         bzero (buffer,999999);
         strcpy(buffer,frame->imageData);
    n=write(sockfd,buffer,strlen(buffer));
    if(n <0)
    {
        error("ERROR READING FROM SOCKET");
    }
    //printf("%s\n",buffer);


    }
return 0;
}

This is how I receive data at the server:

void HostConnector::readyRead()
{
    QByteArray Data = socket->readAll();

    IplImage* frame = new IplImage();
    frame->imageData = Data.data();

    cvShowImage( "mywindow", frame ); //show the frame in a window

}

But I am receiving this error:

OpenCV Error: Bad flag (parameter or structure field) (unrecognized or unusupported array type) in cvGetMat, file /home/kato/GP/src/OpenCV-2.4.2/modules/core/src/array.cpp,line 2482

Qt has caught an exception thrown from an event handler. Throwing exceptions from an event handler is not supported in Qt.You must reimplement QApplication::notify() and catch all exceptions there

terminate called after throwing an instance of 'cv::Exception',error:(-206) Unrecognized or unsupported array type in function cvGetMat.

Does anyone knows how to solve this issue ??

Thanks in advance.