Question

void detect_eye_in_image()
{
    CvRect *face = (CvRect*)cvGetSeqElem(faces, 0);
            
printf("\nIn detect_eye_in_image() %d %d %d %d\n\n",imgcpy->height,imgcpy->width,face->width,face->height);
        cvSetImageROI(
        imgcpy,                    /* the source image */
        cvRect(
            face->x,            /* x = start from leftmost */
            face->y , /* y = a few pixels from the top */
            face->width,        /* width = same width with the face */
            face->height/3    /* height = 1/3 of face height */
        )
    );

printf("\nIn detect_eye_in_image()");
        CvSeq *eyes = cvHaarDetectObjects(
        imgcpy,            /* the source image, with the
                           estimated location defined */
        cascade,      /* the eye classifier */
        storage,        /* memory buffer */
        1.15, 3, 0,     /* tune for your app */
        cvSize(25,25)  /* minimum detection scale */
    );
   printf("\nIn detect_eye_in_image()");
    /* draw a rectangle for each detected eye */
   // for( i = 0; i < (eyes ? eyes->total : 0); i++ ) 
    {
        /* get one eye */
        CvRect *eye = (CvRect*)cvGetSeqElem(eyes, 0);
        /* draw a red rectangle */
        cvRectangle(
            imgcpy,
            cvPoint(eye->x, eye->y),
            cvPoint(eye->x + eye->width, eye->y + eye->height),
            CV_RGB(255, 0, 0),
            1, 8, 0
        );
    }
printf("\nIn detect_eye_in_image()");
    Show_Image(imgcpy);

cvResetImageROI(imgcpy);
}

In the above function i keep getting the following output:

In detect_eye_in_image() 154 154 154 154

OpenCV Error: Assertion failed (rect.width >= 0 && rect.height >= 0 &&
rect.x < image->width && rect.y < image->height && rect.x + rect.width>= (int)(rect.widt h > 0) && rect.y + rect.height >= (int)(rect.height > 0)) in unknown function, f ile ……..\ocv\opencv\src\cxcore\cxarray.cpp, line 3000

How to fix this problem?

Answer 1

You are probably working outside of the image dimensions. Does any of the values you pass to the cvSetImageROI function lay outside the image boudaries?