enteringblobdetection.cpp

Program use openCV to demo edge detection (algorithm Gradient).

                /* image moments */
                double      M00,X,Y,XX,YY;
                CvMoments   m;
                CvRect      r = ((CvContour*)cnt)->rect;
                CvMat       mat;
                if(r.height < S.height*m_HMin || r.width < S.width*m_WMin) continue;
                cvMoments( cvGetSubRect(pFGMask,&mat,r), &m, 0 );
                M00 = cvGetSpatialMoment( &m, 0, 0 );
                if(M00 <= 0 ) continue;
                X = cvGetSpatialMoment( &m, 1, 0 )/M00;
                Y = cvGetSpatialMoment( &m, 0, 1 )/M00;
                XX = (cvGetSpatialMoment( &m, 2, 0 )/M00) - X*X;
                YY = (cvGetSpatialMoment( &m, 0, 2 )/M00) - Y*Y;
                NewBlob = cvBlob(r.x+(float)X,r.y+(float)Y,(float)(4*sqrt(XX)),(float)(4*sqrt(YY)));
                Blobs.AddBlob(&NewBlob);
            }/* next contour */
            cvReleaseImage(&pIB);
        }/* one contour - one blob */

        {/* Delete small and intersected blobs */
            int i;
            for(i=Blobs.GetBlobNum();i>0;i--)
            {
                CvBlob* pB = Blobs.GetBlob(i-1);

                if(pB->h < S.height*m_HMin || pB->w < S.width*m_WMin)
                {
                    Blobs.DelBlob(i-1);
                    continue;
                }
                if(pOldBlobList)
                {
                    int j;
                    for(j=pOldBlobList->GetBlobNum();j>0;j--)
                    {
                        CvBlob* pBOld = pOldBlobList->GetBlob(j-1);
                        if((fabs(pBOld->x-pB->x) < (CV_BLOB_RX(pBOld)+CV_BLOB_RX(pB))) &&
                           (fabs(pBOld->y-pB->y) < (CV_BLOB_RY(pBOld)+CV_BLOB_RY(pB))))
                        {/* intersection is present, delete blob from list*/
                            Blobs.DelBlob(i-1);
                            break;
                        }
                    }/* checl next old blob */
                }/*if pOldBlobList */
            }/* check next blob */
        }/* Delete small and intersected blobs */

        {/* bubble sort blobs by size */
            int N = Blobs.GetBlobNum();
            int i,j;
            for(i=1;i<N;++i)
            {
                for(j=i;j>0;--j)
                {
                    CvBlob  temp;
                    float   AreaP, AreaN;
                    CvBlob* pP = Blobs.GetBlob(j-1);
                    CvBlob* pN = Blobs.GetBlob(j);
                    AreaP = CV_BLOB_WX(pP)*CV_BLOB_WY(pP);
                    AreaN = CV_BLOB_WX(pN)*CV_BLOB_WY(pN);
                    if(AreaN < AreaP)break;
                    temp = pN[0];
                    pN[0] = pP[0];
                    pP[0] = temp;
                }
            }
            /* copy only first 10 blobs */
            for(i=0;i<MIN(N,10);++i)
            {
                m_pBlobLists[0]->AddBlob(Blobs.GetBlob(i));
            }
        }/* sort blobs by size */
        cvReleaseMemStorage(&storage);
    }/* create Blobs */

    {/* shift each track */
        int     j;
        for(j=0;j<m_TrackNum;++j)
        {
            int     i;
            DefSeq* pTrack = m_TrackSeq+j;
            for(i=SEQ_SIZE-1;i>0;--i)pTrack->pBlobs[i]=pTrack->pBlobs[i-1];
            pTrack->pBlobs[0] = NULL;
            if(pTrack->size == SEQ_SIZE)pTrack->size--;
        }
    }/* shift each track */

    /* analize blob list to find best blob trajectory */
    {/* analize blob list to find best blob trajectory */
        double      BestError = -1;
        int         BestTrack = -1;;
        CvBlobSeq*  pNewBlobs = m_pBlobLists[0];
        int         i;
        int         NewTrackNum = 0;
        for(i=pNewBlobs->GetBlobNum();i>0;--i)
        {
            CvBlob* pBNew = pNewBlobs->GetBlob(i-1);
            int     j;
            int     AsignedTrack = 0;
            for(j=0;j<m_TrackNum;++j)
            {
                double  dx,dy;
                DefSeq* pTrack = m_TrackSeq+j;
                CvBlob* pLastBlob = pTrack->size>0?pTrack->pBlobs[1]:NULL;
                if(pLastBlob == NULL) continue;
                dx = fabs(CV_BLOB_X(pLastBlob)-CV_BLOB_X(pBNew));
                dy = fabs(CV_BLOB_Y(pLastBlob)-CV_BLOB_Y(pBNew));
                if(dx > 2*CV_BLOB_WX(pLastBlob) || dy > 2*CV_BLOB_WY(pLastBlob)) continue;
                AsignedTrack++;
                if(pTrack->pBlobs[0]==NULL)
                {/*fill existed track */
                    pTrack->pBlobs[0] = pBNew;
                    pTrack->size++;
                }
                else if((m_TrackNum+NewTrackNum)<SEQ_NUM)
                { /* duplicate existed track */
                    m_TrackSeq[m_TrackNum+NewTrackNum] = pTrack[0];
                    m_TrackSeq[m_TrackNum+NewTrackNum].pBlobs[0] = pBNew;
                    NewTrackNum++;
                }
            }/* next track */

            if(AsignedTrack==0 && (m_TrackNum+NewTrackNum)<SEQ_NUM )
            {/* init new track */
                m_TrackSeq[m_TrackNum+NewTrackNum].size = 1;
                m_TrackSeq[m_TrackNum+NewTrackNum].pBlobs[0] = pBNew;
                NewTrackNum++;
            }
        }/* next new blob */

        m_TrackNum += NewTrackNum;

        /* check each track */
        for(i=0;i<m_TrackNum;++i)
        {
            int     Good = 1;
            DefSeq* pTrack = m_TrackSeq+i;
            CvBlob* pBNew = pTrack->pBlobs[0];
            if(pTrack->size != SEQ_SIZE) continue;
            if(pBNew == NULL ) continue;
            
            /* check intersection last blob with existed */
            if(Good && pOldBlobList)
            { /* check intersection last blob with existed */
                int     k;
                for(k=pOldBlobList->GetBlobNum();k>0;--k)
                {
                    CvBlob* pBOld = pOldBlobList->GetBlob(k-1);
                    if((fabs(pBOld->x-pBNew->x) < (CV_BLOB_RX(pBOld)+CV_BLOB_RX(pBNew))) &&
                       (fabs(pBOld->y-pBNew->y) < (CV_BLOB_RY(pBOld)+CV_BLOB_RY(pBNew))))
                        Good = 0;
                }
            }/* check intersection last blob with existed */

            /* check distance to image border */
            if(Good)
            { /* check distance to image border */
                float    dx = MIN(pBNew->x,S.width-pBNew->x)/CV_BLOB_RX(pBNew);
                float    dy = MIN(pBNew->y,S.height-pBNew->y)/CV_BLOB_RY(pBNew);
                if(dx < m_MinDistToBorder || dy < m_MinDistToBorder) Good = 0;
            }/* check distance to image border */

            /* check uniform moveing */
            if(Good)
            {/* check uniform moveing */
                double      Error = 0;
                int         N = pTrack->size;
                CvBlob**    pBL = pTrack->pBlobs;
                float       sum[2] = {0,0};   
                float       jsum[2] = {0,0};
                float       a[2],b[2]; /* estimated parameters of moving x(t) = a*t+b*/
                int         j;
                
                for(j=0;j<N;++j)
                {
                    float   x = pBL[j]->x;
                    float   y = pBL[j]->y;
                    sum[0] += x;
                    jsum[0] += j*x;
                    sum[1] += y;
                    jsum[1] += j*y;
                }
                a[0] = 6*((1-N)*sum[0]+2*jsum[0])/(N*(N*N-1));
                b[0] = -2*((1-2*N)*sum[0]+3*jsum[0])/(N*(N+1));
                a[1] = 6*((1-N)*sum[1]+2*jsum[1])/(N*(N*N-1));
                b[1] = -2*((1-2*N)*sum[1]+3*jsum[1])/(N*(N+1));
                for(j=0;j<N;++j)
                {
                    Error += 
                        pow(a[0]*j+b[0]-pBL[j]->x,2)+
                        pow(a[1]*j+b[1]-pBL[j]->y,2);
                }
                Error = sqrt(Error/N);
                if( Error > S.width*0.01 || 
                    fabs(a[0])>S.width*0.1 ||
                    fabs(a[1])>S.height*0.1)
                    Good = 0;
                
                /* new best trajectory */
                if(Good && (BestError == -1 || BestError > Error))
                {/* new best trajectory */
                    BestTrack = i;
                    BestError = Error;
                }/* new best trajectory */
            }/* check uniform moveing */
        }/* next track */

        #if 0
        {/**/
            printf("BlobDetector configurations = %d [",m_TrackNum);
            int i;
            for(i=0;i<SEQ_SIZE;++i)
            {
                printf("%d,",m_pBlobLists[i]?m_pBlobLists[i]->GetBlobNum():0);
            }
            printf("]\n");
        
        }
        #endif

        if(BestTrack >= 0)
        {/* put new blob to output and delete from blob list */
            assert(m_TrackSeq[BestTrack].size == SEQ_SIZE);
            assert(m_TrackSeq[BestTrack].pBlobs[0]);
            pNewBlobList->AddBlob(m_TrackSeq[BestTrack].pBlobs[0]);
            m_TrackSeq[BestTrack].pBlobs[0] = NULL;
            m_TrackSeq[BestTrack].size--;
            res = 1;
        }/* put new blob to output and mark in blob list to delete*/
    }/* analize blod list to find best blob trajectory */

    {/* delete bad tracks */
        int i;
        for(i=m_TrackNum-1;i>=0;--i)
        {/* delete bad tracks */
            if(m_TrackSeq[i].pBlobs[0]) continue;
            if(m_TrackNum>0)
                m_TrackSeq[i] = m_TrackSeq[--m_TrackNum];
        }/* delete bad tracks */
    }

#ifdef USE_OBJECT_DETECTOR
    if( m_split_detector && pNewBlobList->GetBlobNum() > 0 )
    {
        int num_new_blobs = pNewBlobList->GetBlobNum();
        int i = 0;

        if( m_roi_seq ) cvClearSeq( m_roi_seq );
        m_debug_blob_seq.Clear();
        for( i = 0; i < num_new_blobs; ++i )
        {
            CvBlob* b = pNewBlobList->GetBlob(i);
            CvMat roi_stub;
            CvMat* roi_mat = 0;
            CvMat* scaled_roi_mat = 0;

            CvDetectedBlob d_b = cvDetectedBlob( CV_BLOB_X(b), CV_BLOB_Y(b), CV_BLOB_WX(b), CV_BLOB_WY(b), 0 );
            m_debug_blob_seq.AddBlob(&d_b);

            float scale = m_param_roi_scale * m_min_window_size.height / CV_BLOB_WY(b);
            
            float b_width =   MAX(CV_BLOB_WX(b), m_min_window_size.width / scale)
                            + (m_param_roi_scale - 1.0F) * (m_min_window_size.width / scale)
                            + 2.0F * m_max_border / scale;
            float b_height = CV_BLOB_WY(b) * m_param_roi_scale + 2.0F * m_max_border / scale;

            CvRect roi = cvRectIntersection( cvRect( cvFloor(CV_BLOB_X(b) - 0.5F*b_width),
                                                     cvFloor(CV_BLOB_Y(b) - 0.5F*b_height),
                                                     cvCeil(b_width), cvCeil(b_height) ),
                                             cvRect( 0, 0, pImg->width, pImg->height ) );
            if( roi.width <= 0 || roi.height <= 0 )
                continue;

            if( m_roi_seq ) cvSeqPush( m_roi_seq, &roi );

            roi_mat = cvGetSubRect( pImg, &roi_stub, roi );
            scaled_roi_mat = cvCreateMat( cvCeil(scale*roi.height), cvCeil(scale*roi.width), CV_8UC3 );
            cvResize( roi_mat, scaled_roi_mat );

            m_detected_blob_seq.Clear();
            m_split_detector->Detect( scaled_roi_mat, &m_detected_blob_seq );
            cvReleaseMat( &scaled_roi_mat );

            for( int k = 0; k < m_detected_blob_seq.GetBlobNum(); ++k )
            {
                CvDetectedBlob* b = (CvDetectedBlob*) m_detected_blob_seq.GetBlob(k);

                /* scale and shift each detected blob back to the original image coordinates */
                CV_BLOB_X(b) = CV_BLOB_X(b) / scale + roi.x;
                CV_BLOB_Y(b) = CV_BLOB_Y(b) / scale + roi.y;
                CV_BLOB_WX(b) /= scale;
                CV_BLOB_WY(b) /= scale;

                CvDetectedBlob d_b = cvDetectedBlob( CV_BLOB_X(b), CV_BLOB_Y(b), CV_BLOB_WX(b), CV_BLOB_WY(b), 1,
                        b->response );
                m_debug_blob_seq.AddBlob(&d_b);
            }
            
            if( m_detected_blob_seq.GetBlobNum() > 1 )
            {
                /*
                 * Split blob
                 * The original blob is replaced by the first detected blob,
                 * remaining detected blobs are added to the end of the sequence
                 */
                CvBlob* first_b = m_detected_blob_seq.GetBlob(0);
                CV_BLOB_X(b)  = CV_BLOB_X(first_b);  CV_BLOB_Y(b)  = CV_BLOB_Y(first_b);
                CV_BLOB_WX(b) = CV_BLOB_WX(first_b); CV_BLOB_WY(b) = CV_BLOB_WY(first_b);

                for( int j = 1; j < m_detected_blob_seq.GetBlobNum(); ++j )
                {
                    CvBlob* detected_b = m_detected_blob_seq.GetBlob(j);
                    pNewBlobList->AddBlob(detected_b);
                }
            }
        } /* for each new blob */
        for( i = 0; i < pNewBlobList->GetBlobNum(); ++i )
        {
            CvBlob* b = pNewBlobList->GetBlob(i);
            CvDetectedBlob d_b = cvDetectedBlob( CV_BLOB_X(b), CV_BLOB_Y(b), CV_BLOB_WX(b), CV_BLOB_WY(b), 2 );
            m_debug_blob_seq.AddBlob(&d_b);
        }
    } // if( m_split_detector )
#endif

    return res;
}/* cvDetectNewBlob */