Segmentation fault with iplmage pointer, ROS node.

edit

I'm trying to detect a blob on a video feed with cvBlob lib in my ROS node. I think, I made a mistake with pointers, but I can't figure out where.

Moreover, do I have to free some of this variable?

Mat& corridorProces(Mat& resultImg)
{   
    Mat srcMat=resultImg.clone();
    cvtColor( resultImg, resultImg, CV_RGB2GRAY );
    IplImage src= resultImg.clone();
    IplImage *src_g= new IplImage(src);
    IplImage *src_g_inv=new IplImage(src);
    cvThreshold(src_g, src_g_inv,35,255, CV_THRESH_BINARY_INV);
    cvThreshold(src_g, src_g,40,255, CV_THRESH_BINARY);    
    IplImage *labelImg=cvCreateImage(cvGetSize(src_g), IPL_DEPTH_LABEL, 1);
    cvb::CvBlobs blobs;
    unsigned int result=cvb::cvLabel(src_g, labelImg, blobs);   
...
}