Cannot display largest blob

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What steps will reproduce the problem?
1. First i declare the maxBlob: CBlob * maxBlob;
2. Display the blob by using maxBlob->Fillblob(destination, 
CV_RGB(255,255,255));
3. The code is:

//load binary image
IplImage * inputImage = cvLoadImage("fill.jpg");

CBlobResult blobs;
blobs = CBlobResult( inputImage, NULL, 0 ); 

// number of blobs
int n = blobs.GetNumBlobs();
cout<<"number of blobs: "<<n<<endl;

CBlob *currentBlob;
CBlob *maxBlob;
double max=0.0,currentBlobArea=0.0;
IplImage * imgBlob=cvCreateImage(cvGetSize(inputImage),8,1);

for (int i=0; i<n; i++ )
{   
currentBlob = blobs.GetBlob(i);
//if currentBlob area is largest, fill the imgBlob;
currentBlobArea = currentBlob->Area();

    if(currentBlobArea>max){
        max = currentBlobArea;
        maxBlob = currentBlob;
    }
}   
cout<<"largest area is: "<<max<<endl;
maxBlob->FillBlob(imgBlob, CV_RGB(255,255,255));


What is the expected output? What do you see instead?
I expected to see the largest blob with a black background. But what i get is a 
totally grey output.

What version of the product are you using? On what operating system?
I am using OpenCV 2.1. Cvblob i downloaded from wiki. I am using window7

Please provide any additional information below.
I follow the instruction in the wiki to install the lib. I can detect the 
number of blobs in the image, and can identify their area. But when i want to 
print the largest blob, the image is, don't know whey stretched, or totally 
grey image is come out.

Please help me. Tq.

Original issue reported on code.google.com by [email protected] on 1 Sep 2011 at 9:00