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You can use template matching for solve this problem before matching you have to use below

void bhDrawBox2D(IplImage* srcImage,CvBox2D box2d,CvScalar color,int thickness)
{
  CvPoint2D32f pts[4];
  cvBoxPoints(box2d,pts);
  for (int i=0; i < 3;i++)
  {
      cvLine(srcImage, cvPointFrom32f(pts[i]),cvPointFrom32f(pts[i+1]),color,thickness);
  }
  cvLine(srcImage, cvPointFrom32f(pts[3]),cvPointFrom32f(pts[0]),color,thickness);

}
CvBox2D bhGetImageBox2d(IplImage* srcImage)
{
    CvBox2D result;
    IplImage* tempImg = cvCloneImage(srcImage);
    CvMemStorage* storage = cvCreateMemStorage(0);
    CvSeq* seq = 0;
     cvFindContours(tempImg,storage,&seq,sizeof(CvContour),CV_RETR_EXTERNAL);
    result = cvMinAreaRect2(seq,storage);

        cvReleaseMemStorage(&storage);
    cvReleaseImage(&tempImg);
    return result;
}
int main(int argc, char** argv )
{
    IplImage* srcImg = cvLoadImage("c:\\org.jpg",0);
    IplImage* tempImg = cvLoadImage("c:\\temp.jpg",0);
    cvThreshold(tempImg,tempImg,128,255,CV_THRESH_OTSU);
    IplImage* orgsrcImg = cvCloneImage(srcImg);

    cvNot(srcImg,srcImg);
    cvNot(tempImg,tempImg);



    CvBox2D tempBox = bhGetImageBox2d(tempImg);

    cvCanny(srcImg,srcImg,10,50);
    cvSmooth(srcImg,srcImg,CV_GAUSSIAN,9);
    cvCanny(tempImg,tempImg,10,50);
    cvSmooth(tempImg,tempImg,CV_GAUSSIAN,9);


    IplImage* resultImg;
    IplImage* resultImg2;
    resultImg = cvCreateImage(cvSize(srcImg->width-tempImg->width+1,srcImg->height-tempImg->height+1),32,1);
    resultImg2= cvCreateImage(cvSize(srcImg->width-tempImg->width+1,srcImg->height-tempImg->height+1),8,1);

    cvMatchTemplate(srcImg,tempImg,resultImg,2);
    double minV,maxV;

    cvNormalize(resultImg,resultImg2,0,255,CV_MINMAX);
    cvMinMaxLoc(resultImg2,&minV,&maxV);
    cvThreshold(resultImg2,resultImg2,maxV - 60,255,CV_THRESH_BINARY);

    CvMemStorage* storage = cvCreateMemStorage(0);
    CvSeq* seq = 0;
    cvFindContours(resultImg2,storage,&seq,sizeof(CvContour),CV_RETR_EXTERNAL);

    for (CvSeq* c= seq;c != 0 ;c = c->h_next)
    {
        CvRect r = cvBoundingRect(c);
        cvSetImageROI(resultImg,r);
        CvPoint minPnt,maxPnt;
        cvMinMaxLoc(resultImg,&minV,&maxV,&minPnt,&maxPnt);
        tempBox.center = cvPoint2D32f(maxPnt.x + r.x + tempImg->width/2,maxPnt.y+r.y + tempImg->height/2);

        bhDrawBox2D(orgsrcImg,tempBox,cvScalarAll(128),2);
        cvResetImageROI(resultImg);

    }
    cvReleaseMemStorage(&storage);
    cvShowImage("view",orgsrcImg);

    cvWaitKey(0);

}

You can use template matching for solve this problem before matching you have to use below do preprocessing by canny & smooth.

void bhDrawBox2D(IplImage* srcImage,CvBox2D box2d,CvScalar color,int thickness)
{
  CvPoint2D32f pts[4];
  cvBoxPoints(box2d,pts);
  for (int i=0; i < 3;i++)
  {
      cvLine(srcImage, cvPointFrom32f(pts[i]),cvPointFrom32f(pts[i+1]),color,thickness);
  }
  cvLine(srcImage, cvPointFrom32f(pts[3]),cvPointFrom32f(pts[0]),color,thickness);

}
CvBox2D bhGetImageBox2d(IplImage* srcImage)
{
    CvBox2D result;
    IplImage* tempImg = cvCloneImage(srcImage);
    CvMemStorage* storage = cvCreateMemStorage(0);
    CvSeq* seq = 0;
     cvFindContours(tempImg,storage,&seq,sizeof(CvContour),CV_RETR_EXTERNAL);
    result = cvMinAreaRect2(seq,storage);

        cvReleaseMemStorage(&storage);
    cvReleaseImage(&tempImg);
    return result;
}
int main(int argc, char** argv )
{
    IplImage* srcImg = cvLoadImage("c:\\org.jpg",0);
    IplImage* tempImg = cvLoadImage("c:\\temp.jpg",0);
    cvThreshold(tempImg,tempImg,128,255,CV_THRESH_OTSU);
    IplImage* orgsrcImg = cvCloneImage(srcImg);

    cvNot(srcImg,srcImg);
    cvNot(tempImg,tempImg);



    CvBox2D tempBox = bhGetImageBox2d(tempImg);

    cvCanny(srcImg,srcImg,10,50);
    cvSmooth(srcImg,srcImg,CV_GAUSSIAN,9);
    cvCanny(tempImg,tempImg,10,50);
    cvSmooth(tempImg,tempImg,CV_GAUSSIAN,9);


    IplImage* resultImg;
    IplImage* resultImg2;
    resultImg = cvCreateImage(cvSize(srcImg->width-tempImg->width+1,srcImg->height-tempImg->height+1),32,1);
    resultImg2= cvCreateImage(cvSize(srcImg->width-tempImg->width+1,srcImg->height-tempImg->height+1),8,1);

    cvMatchTemplate(srcImg,tempImg,resultImg,2);
    double minV,maxV;

    cvNormalize(resultImg,resultImg2,0,255,CV_MINMAX);
    cvMinMaxLoc(resultImg2,&minV,&maxV);
    cvThreshold(resultImg2,resultImg2,maxV - 60,255,CV_THRESH_BINARY);

    CvMemStorage* storage = cvCreateMemStorage(0);
    CvSeq* seq = 0;
    cvFindContours(resultImg2,storage,&seq,sizeof(CvContour),CV_RETR_EXTERNAL);

    for (CvSeq* c= seq;c != 0 ;c = c->h_next)
    {
        CvRect r = cvBoundingRect(c);
        cvSetImageROI(resultImg,r);
        CvPoint minPnt,maxPnt;
        cvMinMaxLoc(resultImg,&minV,&maxV,&minPnt,&maxPnt);
        tempBox.center = cvPoint2D32f(maxPnt.x + r.x + tempImg->width/2,maxPnt.y+r.y + tempImg->height/2);

        bhDrawBox2D(orgsrcImg,tempBox,cvScalarAll(128),2);
        cvResetImageROI(resultImg);

    }
    cvReleaseMemStorage(&storage);
    cvShowImage("view",orgsrcImg);

    cvWaitKey(0);

}