OpenCV can't be used in ROS

edit

I have been trouble by opencv problems. I have planed to transport my windows's code into ROS, which I have tested by local video files. I found that ROS doesn't support local video files, until ffmpeg has been installed. And Checking my ubuntu that it had been installed, I find ROS didn't support local video files neither.

I reinstall my ffmpeg and my opencv2.2, which I find my ROS doesn't support opencv unluckily. I test my older packages, such as gencam_cu. It all doesn't work, while it will works very well without opencv, like usb_cam. I think my ROS system maybe disorder. So I reinstall my ROS refer to ROS.

But also it doesn't work. Especially, when uses "cvCaptureFromCAM" it can't get frames information. Try to find the reason for this problem, but I am so disappointed. I have been bored for many days. Could some one give me helps?

Given a example, codes below

Class UsbCamNode {Public :


ros::NodeHandle &node_;
sensor_msgs::Image img_;

std::string video_device_name_;
std::string io_method_name_;
int image_width_, image_height_;
std::string pixel_format_name_;

ros::Time next_time_;
int count_;

IplImage* src;
IplImage* src_canny;
CvCapture* capture;

image_transport::Publisher image_pub;

UsbCamNode(ros::NodeHandle &node):node_(node)
{
    src=NULL;
    capture=NULL;

    image_transport::ImageTransport it(node);

    image_pub=it.advertise("image_raw",1);
    int camera_num=0;
    ros::NodeHandle nh("~");
    nh.getParam("camera_index",camera_num);
    printf("%d",camera_num);

    if(NULL==(capture=cvCaptureFromCAM(camera_num)))
    {
        printf("\nError on cvCaptureFromCAM");
    }
    if(NULL==(src=cvQueryFrame(capture)))
    {
        printf("\nError on cvQueryFrame");  
    }



    printf("Acquired image (%d/%d%)\n",src->width,src->height);
    printf("Channels (%d)\n",src->nChannels);
    printf("Depth (%d)\n",src->depth);

cvNamedWindow("Capture",CV_WINDOW_AUTOSIZE);
cvNamedWindow("Canny",CV_WINDOW_AUTOSIZE);
cvMoveWindow("Capture",60,70);
next_time_=ros::Time::now();
count_=0;
}

virtual ~UsbCamNode()
{
    cvReleaseCapture(&capture);

    cvDestroyWindow("Capture");
    cvDestroyWindow("Canny");
}

bool take_and_send_image()
{
    int key;
    if(NULL==(src=cvQueryFrame(capture)))
    {   
        printf("\nError on cvQueryFrame");
    }
    else
    {

        cvShowImage("Capture",src);
        src_canny=DoCanny(src);
        cvShowImage("Canny",src_canny);
        key=cvWaitKey(10);

    //fill image message
    fillImage(img_,"mono8",src_canny->height,src_canny->width,src_canny->nChannels*src_canny->width,src_canny->imageData);
    //publish
    image_pub.publish(img_);
    return true;
    }
}

bool spin()
{
    while(node_.ok())
    {   
          if(take_and_send_image())
      {
        count_++;
        ros::Time now_time=ros::Time::now();
        if(now_time>next_time_)
        {   
            std::cout<<count_<<"frames/sec at"<<now_time<<std::endl;
            count_=0;
            next_time_=next_time_+ros::Duration(1,0);
        }
      } else {
        ROS_ERROR("could not take the image");
        usleep(1000000);
        }
    }
    return true;
} };

And it will show the results that: 0 Error on cvCaptureFromCAM Segmentation fault

More, I find my problems are similar with dkst. I try all my methods as possible as I can think,but I did solve these problems. So call for help here

Thanks.