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41#include "_cv.h"
42#include <float.h>
43#include <stdio.h>
44
45static void
46intersect( CvPoint2D32f pt, CvSize win_size, CvSize imgSize,
47           CvPoint* min_pt, CvPoint* max_pt )
48{
49    CvPoint ipt;
50
51    ipt.x = cvFloor( pt.x );
52    ipt.y = cvFloor( pt.y );
53
54    ipt.x -= win_size.width;
55    ipt.y -= win_size.height;
56
57    win_size.width = win_size.width * 2 + 1;
58    win_size.height = win_size.height * 2 + 1;
59
60    min_pt->x = MAX( 0, -ipt.x );
61    min_pt->y = MAX( 0, -ipt.y );
62    max_pt->x = MIN( win_size.width, imgSize.width - ipt.x );
63    max_pt->y = MIN( win_size.height, imgSize.height - ipt.y );
64}
65
66
67static int icvMinimalPyramidSize( CvSize imgSize )
68{
69    return cvAlign(imgSize.width,8) * imgSize.height / 3;
70}
71
72
73static void
74icvInitPyramidalAlgorithm( const CvMat* imgA, const CvMat* imgB,
75                           CvMat* pyrA, CvMat* pyrB,
76                           int level, CvTermCriteria * criteria,
77                           int max_iters, int flags,
78                           uchar *** imgI, uchar *** imgJ,
79                           int **step, CvSize** size,
80                           double **scale, uchar ** buffer )
81{
82    CV_FUNCNAME( "icvInitPyramidalAlgorithm" );
83
84    __BEGIN__;
85
86    const int ALIGN = 8;
87    int pyrBytes, bufferBytes = 0, elem_size;
88    int level1 = level + 1;
89
90    int i;
91    CvSize imgSize, levelSize;
92
93    *buffer = 0;
94    *imgI = *imgJ = 0;
95    *step = 0;
96    *scale = 0;
97    *size = 0;
98
99    /* check input arguments */
100    if( ((flags & CV_LKFLOW_PYR_A_READY) != 0 && !pyrA) ||
101        ((flags & CV_LKFLOW_PYR_B_READY) != 0 && !pyrB) )
102        CV_ERROR( CV_StsNullPtr, "Some of the precomputed pyramids are missing" );
103
104    if( level < 0 )
105        CV_ERROR( CV_StsOutOfRange, "The number of pyramid layers is negative" );
106
107    switch( criteria->type )
108    {
109    case CV_TERMCRIT_ITER:
110        criteria->epsilon = 0.f;
111        break;
112    case CV_TERMCRIT_EPS:
113        criteria->max_iter = max_iters;
114        break;
115    case CV_TERMCRIT_ITER | CV_TERMCRIT_EPS:
116        break;
117    default:
118        assert( 0 );
119        CV_ERROR( CV_StsBadArg, "Invalid termination criteria" );
120    }
121
122    /* compare squared values */
123    criteria->epsilon *= criteria->epsilon;
124
125    /* set pointers and step for every level */
126    pyrBytes = 0;
127
128    imgSize = cvGetSize(imgA);
129    elem_size = CV_ELEM_SIZE(imgA->type);
130    levelSize = imgSize;
131
132    for( i = 1; i < level1; i++ )
133    {
134        levelSize.width = (levelSize.width + 1) >> 1;
135        levelSize.height = (levelSize.height + 1) >> 1;
136
137        int tstep = cvAlign(levelSize.width,ALIGN) * elem_size;
138        pyrBytes += tstep * levelSize.height;
139    }
140
141    assert( pyrBytes <= imgSize.width * imgSize.height * elem_size * 4 / 3 );
142
143    /* buffer_size = <size for patches> + <size for pyramids> */
144    bufferBytes = (int)((level1 >= 0) * ((pyrA->data.ptr == 0) +
145        (pyrB->data.ptr == 0)) * pyrBytes +
146        (sizeof(imgI[0][0]) * 2 + sizeof(step[0][0]) +
147         sizeof(size[0][0]) + sizeof(scale[0][0])) * level1);
148
149    CV_CALL( *buffer = (uchar *)cvAlloc( bufferBytes ));
150
151    *imgI = (uchar **) buffer[0];
152    *imgJ = *imgI + level1;
153    *step = (int *) (*imgJ + level1);
154    *scale = (double *) (*step + level1);
155    *size = (CvSize *)(*scale + level1);
156
157    imgI[0][0] = imgA->data.ptr;
158    imgJ[0][0] = imgB->data.ptr;
159    step[0][0] = imgA->step;
160    scale[0][0] = 1;
161    size[0][0] = imgSize;
162
163    if( level > 0 )
164    {
165        uchar *bufPtr = (uchar *) (*size + level1);
166        uchar *ptrA = pyrA->data.ptr;
167        uchar *ptrB = pyrB->data.ptr;
168
169        if( !ptrA )
170        {
171            ptrA = bufPtr;
172            bufPtr += pyrBytes;
173        }
174
175        if( !ptrB )
176            ptrB = bufPtr;
177
178        levelSize = imgSize;
179
180        /* build pyramids for both frames */
181        for( i = 1; i <= level; i++ )
182        {
183            int levelBytes;
184            CvMat prev_level, next_level;
185
186            levelSize.width = (levelSize.width + 1) >> 1;
187            levelSize.height = (levelSize.height + 1) >> 1;
188
189            size[0][i] = levelSize;
190            step[0][i] = cvAlign( levelSize.width, ALIGN ) * elem_size;
191            scale[0][i] = scale[0][i - 1] * 0.5;
192
193            levelBytes = step[0][i] * levelSize.height;
194            imgI[0][i] = (uchar *) ptrA;
195            ptrA += levelBytes;
196
197            if( !(flags & CV_LKFLOW_PYR_A_READY) )
198            {
199                prev_level = cvMat( size[0][i-1].height, size[0][i-1].width, CV_8UC1 );
200                next_level = cvMat( size[0][i].height, size[0][i].width, CV_8UC1 );
201                cvSetData( &prev_level, imgI[0][i-1], step[0][i-1] );
202                cvSetData( &next_level, imgI[0][i], step[0][i] );
203                cvPyrDown( &prev_level, &next_level );
204            }
205
206            imgJ[0][i] = (uchar *) ptrB;
207            ptrB += levelBytes;
208
209            if( !(flags & CV_LKFLOW_PYR_B_READY) )
210            {
211                prev_level = cvMat( size[0][i-1].height, size[0][i-1].width, CV_8UC1 );
212                next_level = cvMat( size[0][i].height, size[0][i].width, CV_8UC1 );
213                cvSetData( &prev_level, imgJ[0][i-1], step[0][i-1] );
214                cvSetData( &next_level, imgJ[0][i], step[0][i] );
215                cvPyrDown( &prev_level, &next_level );
216            }
217        }
218    }
219
220    __END__;
221}
222
223
224/* compute dI/dx and dI/dy */
225static void
226icvCalcIxIy_32f( const float* src, int src_step, float* dstX, float* dstY, int dst_step,
227                 CvSize src_size, const float* smooth_k, float* buffer0 )
228{
229    int src_width = src_size.width, dst_width = src_size.width-2;
230    int x, height = src_size.height - 2;
231    float* buffer1 = buffer0 + src_width;
232
233    src_step /= sizeof(src[0]);
234    dst_step /= sizeof(dstX[0]);
235
236    for( ; height--; src += src_step, dstX += dst_step, dstY += dst_step )
237    {
238        const float* src2 = src + src_step;
239        const float* src3 = src + src_step*2;
240
241        for( x = 0; x < src_width; x++ )
242        {
243            float t0 = (src3[x] + src[x])*smooth_k[0] + src2[x]*smooth_k[1];
244            float t1 = src3[x] - src[x];
245            buffer0[x] = t0; buffer1[x] = t1;
246        }
247
248        for( x = 0; x < dst_width; x++ )
249        {
250            float t0 = buffer0[x+2] - buffer0[x];
251            float t1 = (buffer1[x] + buffer1[x+2])*smooth_k[0] + buffer1[x+1]*smooth_k[1];
252            dstX[x] = t0; dstY[x] = t1;
253        }
254    }
255}
256
257
258icvOpticalFlowPyrLKInitAlloc_8u_C1R_t icvOpticalFlowPyrLKInitAlloc_8u_C1R_p = 0;
259icvOpticalFlowPyrLKFree_8u_C1R_t icvOpticalFlowPyrLKFree_8u_C1R_p = 0;
260icvOpticalFlowPyrLK_8u_C1R_t icvOpticalFlowPyrLK_8u_C1R_p = 0;
261
262
263CV_IMPL void
264cvCalcOpticalFlowPyrLK( const void* arrA, const void* arrB,
265                        void* pyrarrA, void* pyrarrB,
266                        const CvPoint2D32f * featuresA,
267                        CvPoint2D32f * featuresB,
268                        int count, CvSize winSize, int level,
269                        char *status, float *error,
270                        CvTermCriteria criteria, int flags )
271{
272    uchar *pyrBuffer = 0;
273    uchar *buffer = 0;
274    float* _error = 0;
275    char* _status = 0;
276
277    void* ipp_optflow_state = 0;
278
279    CV_FUNCNAME( "cvCalcOpticalFlowPyrLK" );
280
281    __BEGIN__;
282
283    const int MAX_ITERS = 100;
284
285    CvMat stubA, *imgA = (CvMat*)arrA;
286    CvMat stubB, *imgB = (CvMat*)arrB;
287    CvMat pstubA, *pyrA = (CvMat*)pyrarrA;
288    CvMat pstubB, *pyrB = (CvMat*)pyrarrB;
289    CvSize imgSize;
290    static const float smoothKernel[] = { 0.09375, 0.3125, 0.09375 };  /* 3/32, 10/32, 3/32 */
291
292    int bufferBytes = 0;
293    uchar **imgI = 0;
294    uchar **imgJ = 0;
295    int *step = 0;
296    double *scale = 0;
297    CvSize* size = 0;
298
299    int threadCount = cvGetNumThreads();
300    float* _patchI[CV_MAX_THREADS];
301    float* _patchJ[CV_MAX_THREADS];
302    float* _Ix[CV_MAX_THREADS];
303    float* _Iy[CV_MAX_THREADS];
304
305    int i, l;
306
307    CvSize patchSize = cvSize( winSize.width * 2 + 1, winSize.height * 2 + 1 );
308    int patchLen = patchSize.width * patchSize.height;
309    int srcPatchLen = (patchSize.width + 2)*(patchSize.height + 2);
310
311    CV_CALL( imgA = cvGetMat( imgA, &stubA ));
312    CV_CALL( imgB = cvGetMat( imgB, &stubB ));
313
314    if( CV_MAT_TYPE( imgA->type ) != CV_8UC1 )
315        CV_ERROR( CV_StsUnsupportedFormat, "" );
316
317    if( !CV_ARE_TYPES_EQ( imgA, imgB ))
318        CV_ERROR( CV_StsUnmatchedFormats, "" );
319
320    if( !CV_ARE_SIZES_EQ( imgA, imgB ))
321        CV_ERROR( CV_StsUnmatchedSizes, "" );
322
323    if( imgA->step != imgB->step )
324        CV_ERROR( CV_StsUnmatchedSizes, "imgA and imgB must have equal steps" );
325
326    imgSize = cvGetMatSize( imgA );
327
328    if( pyrA )
329    {
330        CV_CALL( pyrA = cvGetMat( pyrA, &pstubA ));
331
332        if( pyrA->step*pyrA->height < icvMinimalPyramidSize( imgSize ) )
333            CV_ERROR( CV_StsBadArg, "pyramid A has insufficient size" );
334    }
335    else
336    {
337        pyrA = &pstubA;
338        pyrA->data.ptr = 0;
339    }
340
341    if( pyrB )
342    {
343        CV_CALL( pyrB = cvGetMat( pyrB, &pstubB ));
344
345        if( pyrB->step*pyrB->height < icvMinimalPyramidSize( imgSize ) )
346            CV_ERROR( CV_StsBadArg, "pyramid B has insufficient size" );
347    }
348    else
349    {
350        pyrB = &pstubB;
351        pyrB->data.ptr = 0;
352    }
353
354    if( count == 0 )
355        EXIT;
356
357    if( !featuresA || !featuresB )
358        CV_ERROR( CV_StsNullPtr, "Some of arrays of point coordinates are missing" );
359
360    if( count < 0 )
361        CV_ERROR( CV_StsOutOfRange, "The number of tracked points is negative or zero" );
362
363    if( winSize.width <= 1 || winSize.height <= 1 )
364        CV_ERROR( CV_StsBadSize, "Invalid search window size" );
365
366    for( i = 0; i < threadCount; i++ )
367        _patchI[i] = _patchJ[i] = _Ix[i] = _Iy[i] = 0;
368
369    CV_CALL( icvInitPyramidalAlgorithm( imgA, imgB, pyrA, pyrB,
370        level, &criteria, MAX_ITERS, flags,
371        &imgI, &imgJ, &step, &size, &scale, &pyrBuffer ));
372
373    if( !status )
374        CV_CALL( status = _status = (char*)cvAlloc( count*sizeof(_status[0]) ));
375
376#if 0
377    if( icvOpticalFlowPyrLKInitAlloc_8u_C1R_p &&
378        icvOpticalFlowPyrLKFree_8u_C1R_p &&
379        icvOpticalFlowPyrLK_8u_C1R_p &&
380        winSize.width == winSize.height &&
381        icvOpticalFlowPyrLKInitAlloc_8u_C1R_p( &ipp_optflow_state, imgSize,
382                                               winSize.width*2+1, cvAlgHintAccurate ) >= 0 )
383    {
384        CvPyramid ipp_pyrA, ipp_pyrB;
385        static const double rate[] = { 1, 0.5, 0.25, 0.125, 0.0625, 0.03125, 0.015625, 0.0078125,
386                                       0.00390625, 0.001953125, 0.0009765625, 0.00048828125, 0.000244140625,
387                                       0.0001220703125 };
388        // initialize pyramid structures
389        assert( level < 14 );
390        ipp_pyrA.ptr = imgI;
391        ipp_pyrB.ptr = imgJ;
392        ipp_pyrA.sz = ipp_pyrB.sz = size;
393        ipp_pyrA.rate = ipp_pyrB.rate = (double*)rate;
394        ipp_pyrA.step = ipp_pyrB.step = step;
395        ipp_pyrA.state = ipp_pyrB.state = 0;
396        ipp_pyrA.level = ipp_pyrB.level = level;
397
398        if( !error )
399            CV_CALL( error = _error = (float*)cvAlloc( count*sizeof(_error[0]) ));
400
401        for( i = 0; i < count; i++ )
402            featuresB[i] = featuresA[i];
403
404        if( icvOpticalFlowPyrLK_8u_C1R_p( &ipp_pyrA, &ipp_pyrB,
405            (const float*)featuresA, (float*)featuresB, status, error, count,
406            winSize.width*2 + 1, level, criteria.max_iter,
407            (float)criteria.epsilon, ipp_optflow_state ) >= 0 )
408        {
409            for( i = 0; i < count; i++ )
410                status[i] = status[i] == 0;
411            EXIT;
412        }
413    }
414#endif
415
416    /* buffer_size = <size for patches> + <size for pyramids> */
417    bufferBytes = (srcPatchLen + patchLen * 3) * sizeof( _patchI[0][0] ) * threadCount;
418    CV_CALL( buffer = (uchar*)cvAlloc( bufferBytes ));
419
420    for( i = 0; i < threadCount; i++ )
421    {
422        _patchI[i] = i == 0 ? (float*)buffer : _Iy[i-1] + patchLen;
423        _patchJ[i] = _patchI[i] + srcPatchLen;
424        _Ix[i] = _patchJ[i] + patchLen;
425        _Iy[i] = _Ix[i] + patchLen;
426    }
427
428    memset( status, 1, count );
429    if( error )
430        memset( error, 0, count*sizeof(error[0]) );
431
432    if( !(flags & CV_LKFLOW_INITIAL_GUESSES) )
433        memcpy( featuresB, featuresA, count*sizeof(featuresA[0]));
434
435    /* do processing from top pyramid level (smallest image)
436       to the bottom (original image) */
437    for( l = level; l >= 0; l-- )
438    {
439        CvSize levelSize = size[l];
440        int levelStep = step[l];
441
442        {
443#ifdef _OPENMP
444        #pragma omp parallel for num_threads(threadCount) schedule(dynamic)
445#endif // _OPENMP
446        /* find flow for each given point */
447        for( i = 0; i < count; i++ )
448        {
449            CvPoint2D32f v;
450            CvPoint minI, maxI, minJ, maxJ;
451            CvSize isz, jsz;
452            int pt_status;
453            CvPoint2D32f u;
454            CvPoint prev_minJ = { -1, -1 }, prev_maxJ = { -1, -1 };
455            double Gxx = 0, Gxy = 0, Gyy = 0, D = 0, minEig = 0;
456            float prev_mx = 0, prev_my = 0;
457            int j, x, y;
458            int threadIdx = cvGetThreadNum();
459            float* patchI = _patchI[threadIdx];
460            float* patchJ = _patchJ[threadIdx];
461            float* Ix = _Ix[threadIdx];
462            float* Iy = _Iy[threadIdx];
463
464            v.x = featuresB[i].x;
465            v.y = featuresB[i].y;
466            if( l < level )
467            {
468                v.x += v.x;
469                v.y += v.y;
470            }
471            else
472            {
473                v.x = (float)(v.x * scale[l]);
474                v.y = (float)(v.y * scale[l]);
475            }
476
477            pt_status = status[i];
478            if( !pt_status )
479                continue;
480
481            minI = maxI = minJ = maxJ = cvPoint( 0, 0 );
482
483            u.x = (float) (featuresA[i].x * scale[l]);
484            u.y = (float) (featuresA[i].y * scale[l]);
485
486            intersect( u, winSize, levelSize, &minI, &maxI );
487            isz = jsz = cvSize(maxI.x - minI.x + 2, maxI.y - minI.y + 2);
488            u.x += (minI.x - (patchSize.width - maxI.x + 1))*0.5f;
489            u.y += (minI.y - (patchSize.height - maxI.y + 1))*0.5f;
490
491            if( isz.width < 3 || isz.height < 3 ||
492                icvGetRectSubPix_8u32f_C1R( imgI[l], levelStep, levelSize,
493                    patchI, isz.width*sizeof(patchI[0]), isz, u ) < 0 )
494            {
495                /* point is outside the image. take the next */
496                status[i] = 0;
497                continue;
498            }
499
500            icvCalcIxIy_32f( patchI, isz.width*sizeof(patchI[0]), Ix, Iy,
501                (isz.width-2)*sizeof(patchI[0]), isz, smoothKernel, patchJ );
502
503            for( j = 0; j < criteria.max_iter; j++ )
504            {
505                double bx = 0, by = 0;
506                float mx, my;
507                CvPoint2D32f _v;
508
509                intersect( v, winSize, levelSize, &minJ, &maxJ );
510
511                minJ.x = MAX( minJ.x, minI.x );
512                minJ.y = MAX( minJ.y, minI.y );
513
514                maxJ.x = MIN( maxJ.x, maxI.x );
515                maxJ.y = MIN( maxJ.y, maxI.y );
516
517                jsz = cvSize(maxJ.x - minJ.x, maxJ.y - minJ.y);
518
519                _v.x = v.x + (minJ.x - (patchSize.width - maxJ.x + 1))*0.5f;
520                _v.y = v.y + (minJ.y - (patchSize.height - maxJ.y + 1))*0.5f;
521
522                if( jsz.width < 1 || jsz.height < 1 ||
523                    icvGetRectSubPix_8u32f_C1R( imgJ[l], levelStep, levelSize, patchJ,
524                                                jsz.width*sizeof(patchJ[0]), jsz, _v ) < 0 )
525                {
526                    /* point is outside image. take the next */
527                    pt_status = 0;
528                    break;
529                }
530
531                if( maxJ.x == prev_maxJ.x && maxJ.y == prev_maxJ.y &&
532                    minJ.x == prev_minJ.x && minJ.y == prev_minJ.y )
533                {
534                    for( y = 0; y < jsz.height; y++ )
535                    {
536                        const float* pi = patchI +
537                            (y + minJ.y - minI.y + 1)*isz.width + minJ.x - minI.x + 1;
538                        const float* pj = patchJ + y*jsz.width;
539                        const float* ix = Ix +
540                            (y + minJ.y - minI.y)*(isz.width-2) + minJ.x - minI.x;
541                        const float* iy = Iy + (ix - Ix);
542
543                        for( x = 0; x < jsz.width; x++ )
544                        {
545                            double t0 = pi[x] - pj[x];
546                            bx += t0 * ix[x];
547                            by += t0 * iy[x];
548                        }
549                    }
550                }
551                else
552                {
553                    Gxx = Gyy = Gxy = 0;
554                    for( y = 0; y < jsz.height; y++ )
555                    {
556                        const float* pi = patchI +
557                            (y + minJ.y - minI.y + 1)*isz.width + minJ.x - minI.x + 1;
558                        const float* pj = patchJ + y*jsz.width;
559                        const float* ix = Ix +
560                            (y + minJ.y - minI.y)*(isz.width-2) + minJ.x - minI.x;
561                        const float* iy = Iy + (ix - Ix);
562
563                        for( x = 0; x < jsz.width; x++ )
564                        {
565                            double t = pi[x] - pj[x];
566                            bx += (double) (t * ix[x]);
567                            by += (double) (t * iy[x]);
568                            Gxx += ix[x] * ix[x];
569                            Gxy += ix[x] * iy[x];
570                            Gyy += iy[x] * iy[x];
571                        }
572                    }
573
574                    D = Gxx * Gyy - Gxy * Gxy;
575                    if( D < DBL_EPSILON )
576                    {
577                        pt_status = 0;
578                        break;
579                    }
580
581                    // Adi Shavit - 2008.05
582                    if( flags & CV_LKFLOW_GET_MIN_EIGENVALS )
583                        minEig = (Gyy + Gxx - sqrt((Gxx-Gyy)*(Gxx-Gyy) + 4.*Gxy*Gxy))/(2*jsz.height*jsz.width);
584
585                    D = 1. / D;
586
587                    prev_minJ = minJ;
588                    prev_maxJ = maxJ;
589                }
590
591                mx = (float) ((Gyy * bx - Gxy * by) * D);
592                my = (float) ((Gxx * by - Gxy * bx) * D);
593
594                v.x += mx;
595                v.y += my;
596
597                if( mx * mx + my * my < criteria.epsilon )
598                    break;
599
600                if( j > 0 && fabs(mx + prev_mx) < 0.01 && fabs(my + prev_my) < 0.01 )
601                {
602                    v.x -= mx*0.5f;
603                    v.y -= my*0.5f;
604                    break;
605                }
606                prev_mx = mx;
607                prev_my = my;
608            }
609
610            featuresB[i] = v;
611            status[i] = (char)pt_status;
612            if( l == 0 && error && pt_status )
613            {
614                /* calc error */
615                double err = 0;
616                if( flags & CV_LKFLOW_GET_MIN_EIGENVALS )
617                    err = minEig;
618                else
619                {
620                    for( y = 0; y < jsz.height; y++ )
621                    {
622                        const float* pi = patchI +
623                            (y + minJ.y - minI.y + 1)*isz.width + minJ.x - minI.x + 1;
624                        const float* pj = patchJ + y*jsz.width;
625
626                        for( x = 0; x < jsz.width; x++ )
627                        {
628                            double t = pi[x] - pj[x];
629                            err += t * t;
630                        }
631                    }
632                    err = sqrt(err);
633                }
634                error[i] = (float)err;
635            }
636        } // end of point processing loop (i)
637        }
638    } // end of pyramid levels loop (l)
639
640    __END__;
641
642    if( ipp_optflow_state )
643        icvOpticalFlowPyrLKFree_8u_C1R_p( ipp_optflow_state );
644
645    cvFree( &pyrBuffer );
646    cvFree( &buffer );
647    cvFree( &_error );
648    cvFree( &_status );
649}
650
651
652/* Affine tracking algorithm */
653
654CV_IMPL void
655cvCalcAffineFlowPyrLK( const void* arrA, const void* arrB,
656                       void* pyrarrA, void* pyrarrB,
657                       const CvPoint2D32f * featuresA,
658                       CvPoint2D32f * featuresB,
659                       float *matrices, int count,
660                       CvSize winSize, int level,
661                       char *status, float *error,
662                       CvTermCriteria criteria, int flags )
663{
664    const int MAX_ITERS = 100;
665
666    char* _status = 0;
667    uchar *buffer = 0;
668    uchar *pyr_buffer = 0;
669
670    CV_FUNCNAME( "cvCalcAffineFlowPyrLK" );
671
672    __BEGIN__;
673
674    CvMat stubA, *imgA = (CvMat*)arrA;
675    CvMat stubB, *imgB = (CvMat*)arrB;
676    CvMat pstubA, *pyrA = (CvMat*)pyrarrA;
677    CvMat pstubB, *pyrB = (CvMat*)pyrarrB;
678
679    static const float smoothKernel[] = { 0.09375, 0.3125, 0.09375 };  /* 3/32, 10/32, 3/32 */
680
681    int bufferBytes = 0;
682
683    uchar **imgI = 0;
684    uchar **imgJ = 0;
685    int *step = 0;
686    double *scale = 0;
687    CvSize* size = 0;
688
689    float *patchI;
690    float *patchJ;
691    float *Ix;
692    float *Iy;
693
694    int i, j, k, l;
695
696    CvSize patchSize = cvSize( winSize.width * 2 + 1, winSize.height * 2 + 1 );
697    int patchLen = patchSize.width * patchSize.height;
698    int patchStep = patchSize.width * sizeof( patchI[0] );
699
700    CvSize srcPatchSize = cvSize( patchSize.width + 2, patchSize.height + 2 );
701    int srcPatchLen = srcPatchSize.width * srcPatchSize.height;
702    int srcPatchStep = srcPatchSize.width * sizeof( patchI[0] );
703    CvSize imgSize;
704    float eps = (float)MIN(winSize.width, winSize.height);
705
706    CV_CALL( imgA = cvGetMat( imgA, &stubA ));
707    CV_CALL( imgB = cvGetMat( imgB, &stubB ));
708
709    if( CV_MAT_TYPE( imgA->type ) != CV_8UC1 )
710        CV_ERROR( CV_StsUnsupportedFormat, "" );
711
712    if( !CV_ARE_TYPES_EQ( imgA, imgB ))
713        CV_ERROR( CV_StsUnmatchedFormats, "" );
714
715    if( !CV_ARE_SIZES_EQ( imgA, imgB ))
716        CV_ERROR( CV_StsUnmatchedSizes, "" );
717
718    if( imgA->step != imgB->step )
719        CV_ERROR( CV_StsUnmatchedSizes, "imgA and imgB must have equal steps" );
720
721    if( !matrices )
722        CV_ERROR( CV_StsNullPtr, "" );
723
724    imgSize = cvGetMatSize( imgA );
725
726    if( pyrA )
727    {
728        CV_CALL( pyrA = cvGetMat( pyrA, &pstubA ));
729
730        if( pyrA->step*pyrA->height < icvMinimalPyramidSize( imgSize ) )
731            CV_ERROR( CV_StsBadArg, "pyramid A has insufficient size" );
732    }
733    else
734    {
735        pyrA = &pstubA;
736        pyrA->data.ptr = 0;
737    }
738
739    if( pyrB )
740    {
741        CV_CALL( pyrB = cvGetMat( pyrB, &pstubB ));
742
743        if( pyrB->step*pyrB->height < icvMinimalPyramidSize( imgSize ) )
744            CV_ERROR( CV_StsBadArg, "pyramid B has insufficient size" );
745    }
746    else
747    {
748        pyrB = &pstubB;
749        pyrB->data.ptr = 0;
750    }
751
752    if( count == 0 )
753        EXIT;
754
755    /* check input arguments */
756    if( !featuresA || !featuresB || !matrices )
757        CV_ERROR( CV_StsNullPtr, "" );
758
759    if( winSize.width <= 1 || winSize.height <= 1 )
760        CV_ERROR( CV_StsOutOfRange, "the search window is too small" );
761
762    if( count < 0 )
763        CV_ERROR( CV_StsOutOfRange, "" );
764
765    CV_CALL( icvInitPyramidalAlgorithm( imgA, imgB,
766        pyrA, pyrB, level, &criteria, MAX_ITERS, flags,
767        &imgI, &imgJ, &step, &size, &scale, &pyr_buffer ));
768
769    /* buffer_size = <size for patches> + <size for pyramids> */
770    bufferBytes = (srcPatchLen + patchLen*3)*sizeof(patchI[0]) + (36*2 + 6)*sizeof(double);
771
772    CV_CALL( buffer = (uchar*)cvAlloc(bufferBytes));
773
774    if( !status )
775        CV_CALL( status = _status = (char*)cvAlloc(count) );
776
777    patchI = (float *) buffer;
778    patchJ = patchI + srcPatchLen;
779    Ix = patchJ + patchLen;
780    Iy = Ix + patchLen;
781
782    if( status )
783        memset( status, 1, count );
784
785    if( !(flags & CV_LKFLOW_INITIAL_GUESSES) )
786    {
787        memcpy( featuresB, featuresA, count * sizeof( featuresA[0] ));
788        for( i = 0; i < count * 4; i += 4 )
789        {
790            matrices[i] = matrices[i + 3] = 1.f;
791            matrices[i + 1] = matrices[i + 2] = 0.f;
792        }
793    }
794
795    for( i = 0; i < count; i++ )
796    {
797        featuresB[i].x = (float)(featuresB[i].x * scale[level] * 0.5);
798        featuresB[i].y = (float)(featuresB[i].y * scale[level] * 0.5);
799    }
800
801    /* do processing from top pyramid level (smallest image)
802       to the bottom (original image) */
803    for( l = level; l >= 0; l-- )
804    {
805        CvSize levelSize = size[l];
806        int levelStep = step[l];
807
808        /* find flow for each given point at the particular level */
809        for( i = 0; i < count; i++ )
810        {
811            CvPoint2D32f u;
812            float Av[6];
813            double G[36];
814            double meanI = 0, meanJ = 0;
815            int x, y;
816            int pt_status = status[i];
817            CvMat mat;
818
819            if( !pt_status )
820                continue;
821
822            Av[0] = matrices[i*4];
823            Av[1] = matrices[i*4+1];
824            Av[3] = matrices[i*4+2];
825            Av[4] = matrices[i*4+3];
826
827            Av[2] = featuresB[i].x += featuresB[i].x;
828            Av[5] = featuresB[i].y += featuresB[i].y;
829
830            u.x = (float) (featuresA[i].x * scale[l]);
831            u.y = (float) (featuresA[i].y * scale[l]);
832
833            if( u.x < -eps || u.x >= levelSize.width+eps ||
834                u.y < -eps || u.y >= levelSize.height+eps ||
835                icvGetRectSubPix_8u32f_C1R( imgI[l], levelStep,
836                levelSize, patchI, srcPatchStep, srcPatchSize, u ) < 0 )
837            {
838                /* point is outside the image. take the next */
839                if( l == 0 )
840                    status[i] = 0;
841                continue;
842            }
843
844            icvCalcIxIy_32f( patchI, srcPatchStep, Ix, Iy,
845                (srcPatchSize.width-2)*sizeof(patchI[0]), srcPatchSize,
846                smoothKernel, patchJ );
847
848            /* repack patchI (remove borders) */
849            for( k = 0; k < patchSize.height; k++ )
850                memcpy( patchI + k * patchSize.width,
851                        patchI + (k + 1) * srcPatchSize.width + 1, patchStep );
852
853            memset( G, 0, sizeof( G ));
854
855            /* calculate G matrix */
856            for( y = -winSize.height, k = 0; y <= winSize.height; y++ )
857            {
858                for( x = -winSize.width; x <= winSize.width; x++, k++ )
859                {
860                    double ixix = ((double) Ix[k]) * Ix[k];
861                    double ixiy = ((double) Ix[k]) * Iy[k];
862                    double iyiy = ((double) Iy[k]) * Iy[k];
863
864                    double xx, xy, yy;
865
866                    G[0] += ixix;
867                    G[1] += ixiy;
868                    G[2] += x * ixix;
869                    G[3] += y * ixix;
870                    G[4] += x * ixiy;
871                    G[5] += y * ixiy;
872
873                    // G[6] == G[1]
874                    G[7] += iyiy;
875                    // G[8] == G[4]
876                    // G[9] == G[5]
877                    G[10] += x * iyiy;
878                    G[11] += y * iyiy;
879
880                    xx = x * x;
881                    xy = x * y;
882                    yy = y * y;
883
884                    // G[12] == G[2]
885                    // G[13] == G[8] == G[4]
886                    G[14] += xx * ixix;
887                    G[15] += xy * ixix;
888                    G[16] += xx * ixiy;
889                    G[17] += xy * ixiy;
890
891                    // G[18] == G[3]
892                    // G[19] == G[9]
893                    // G[20] == G[15]
894                    G[21] += yy * ixix;
895                    // G[22] == G[17]
896                    G[23] += yy * ixiy;
897
898                    // G[24] == G[4]
899                    // G[25] == G[10]
900                    // G[26] == G[16]
901                    // G[27] == G[22]
902                    G[28] += xx * iyiy;
903                    G[29] += xy * iyiy;
904
905                    // G[30] == G[5]
906                    // G[31] == G[11]
907                    // G[32] == G[17]
908                    // G[33] == G[23]
909                    // G[34] == G[29]
910                    G[35] += yy * iyiy;
911
912                    meanI += patchI[k];
913                }
914            }
915
916            meanI /= patchSize.width*patchSize.height;
917
918            G[8] = G[4];
919            G[9] = G[5];
920            G[22] = G[17];
921
922            // fill part of G below its diagonal
923            for( y = 1; y < 6; y++ )
924                for( x = 0; x < y; x++ )
925                    G[y * 6 + x] = G[x * 6 + y];
926
927            cvInitMatHeader( &mat, 6, 6, CV_64FC1, G );
928
929            if( cvInvert( &mat, &mat, CV_SVD ) < 1e-4 )
930            {
931                /* bad matrix. take the next point */
932                if( l == 0 )
933                    status[i] = 0;
934                continue;
935            }
936
937            for( j = 0; j < criteria.max_iter; j++ )
938            {
939                double b[6] = {0,0,0,0,0,0}, eta[6];
940                double t0, t1, s = 0;
941
942                if( Av[2] < -eps || Av[2] >= levelSize.width+eps ||
943                    Av[5] < -eps || Av[5] >= levelSize.height+eps ||
944                    icvGetQuadrangleSubPix_8u32f_C1R( imgJ[l], levelStep,
945                    levelSize, patchJ, patchStep, patchSize, Av ) < 0 )
946                {
947                    pt_status = 0;
948                    break;
949                }
950
951                for( y = -winSize.height, k = 0, meanJ = 0; y <= winSize.height; y++ )
952                    for( x = -winSize.width; x <= winSize.width; x++, k++ )
953                        meanJ += patchJ[k];
954
955                meanJ = meanJ / (patchSize.width * patchSize.height) - meanI;
956
957                for( y = -winSize.height, k = 0; y <= winSize.height; y++ )
958                {
959                    for( x = -winSize.width; x <= winSize.width; x++, k++ )
960                    {
961                        double t = patchI[k] - patchJ[k] + meanJ;
962                        double ixt = Ix[k] * t;
963                        double iyt = Iy[k] * t;
964
965                        s += t;
966
967                        b[0] += ixt;
968                        b[1] += iyt;
969                        b[2] += x * ixt;
970                        b[3] += y * ixt;
971                        b[4] += x * iyt;
972                        b[5] += y * iyt;
973                    }
974                }
975
976                icvTransformVector_64d( G, b, eta, 6, 6 );
977
978                Av[2] = (float)(Av[2] + Av[0] * eta[0] + Av[1] * eta[1]);
979                Av[5] = (float)(Av[5] + Av[3] * eta[0] + Av[4] * eta[1]);
980
981                t0 = Av[0] * (1 + eta[2]) + Av[1] * eta[4];
982                t1 = Av[0] * eta[3] + Av[1] * (1 + eta[5]);
983                Av[0] = (float)t0;
984                Av[1] = (float)t1;
985
986                t0 = Av[3] * (1 + eta[2]) + Av[4] * eta[4];
987                t1 = Av[3] * eta[3] + Av[4] * (1 + eta[5]);
988                Av[3] = (float)t0;
989                Av[4] = (float)t1;
990
991                if( eta[0] * eta[0] + eta[1] * eta[1] < criteria.epsilon )
992                    break;
993            }
994
995            if( pt_status != 0 || l == 0 )
996            {
997                status[i] = (char)pt_status;
998                featuresB[i].x = Av[2];
999                featuresB[i].y = Av[5];
1000
1001                matrices[i*4] = Av[0];
1002                matrices[i*4+1] = Av[1];
1003                matrices[i*4+2] = Av[3];
1004                matrices[i*4+3] = Av[4];
1005            }
1006
1007            if( pt_status && l == 0 && error )
1008            {
1009                /* calc error */
1010                double err = 0;
1011
1012                for( y = 0, k = 0; y < patchSize.height; y++ )
1013                {
1014                    for( x = 0; x < patchSize.width; x++, k++ )
1015                    {
1016                        double t = patchI[k] - patchJ[k] + meanJ;
1017                        err += t * t;
1018                    }
1019                }
1020                error[i] = (float)sqrt(err);
1021            }
1022        }
1023    }
1024
1025    __END__;
1026
1027    cvFree( &pyr_buffer );
1028    cvFree( &buffer );
1029    cvFree( &_status );
1030}
1031
1032
1033
1034static void
1035icvGetRTMatrix( const CvPoint2D32f* a, const CvPoint2D32f* b,
1036                int count, CvMat* M, int full_affine )
1037{
1038    if( full_affine )
1039    {
1040        double sa[36], sb[6];
1041        CvMat A = cvMat( 6, 6, CV_64F, sa ), B = cvMat( 6, 1, CV_64F, sb );
1042        CvMat MM = cvMat( 6, 1, CV_64F, M->data.db );
1043
1044        int i;
1045
1046        memset( sa, 0, sizeof(sa) );
1047        memset( sb, 0, sizeof(sb) );
1048
1049        for( i = 0; i < count; i++ )
1050        {
1051            sa[0] += a[i].x*a[i].x;
1052            sa[1] += a[i].y*a[i].x;
1053            sa[2] += a[i].x;
1054
1055            sa[6] += a[i].x*a[i].y;
1056            sa[7] += a[i].y*a[i].y;
1057            sa[8] += a[i].y;
1058
1059            sa[12] += a[i].x;
1060            sa[13] += a[i].y;
1061            sa[14] += 1;
1062
1063            sb[0] += a[i].x*b[i].x;
1064            sb[1] += a[i].y*b[i].x;
1065            sb[2] += b[i].x;
1066            sb[3] += a[i].x*b[i].y;
1067            sb[4] += a[i].y*b[i].y;
1068            sb[5] += b[i].y;
1069        }
1070
1071        sa[21] = sa[0];
1072        sa[22] = sa[1];
1073        sa[23] = sa[2];
1074        sa[27] = sa[6];
1075        sa[28] = sa[7];
1076        sa[29] = sa[8];
1077        sa[33] = sa[12];
1078        sa[34] = sa[13];
1079        sa[35] = sa[14];
1080
1081        cvSolve( &A, &B, &MM, CV_SVD );
1082    }
1083    else
1084    {
1085        double sa[16], sb[4], m[4], *om = M->data.db;
1086        CvMat A = cvMat( 4, 4, CV_64F, sa ), B = cvMat( 4, 1, CV_64F, sb );
1087        CvMat MM = cvMat( 4, 1, CV_64F, m );
1088
1089        int i;
1090
1091        memset( sa, 0, sizeof(sa) );
1092        memset( sb, 0, sizeof(sb) );
1093
1094        for( i = 0; i < count; i++ )
1095        {
1096            sa[0] += a[i].x*a[i].x + a[i].y*a[i].y;
1097            sa[1] += 0;
1098            sa[2] += a[i].x;
1099            sa[3] += a[i].y;
1100
1101            sa[4] += 0;
1102            sa[5] += a[i].x*a[i].x + a[i].y*a[i].y;
1103            sa[6] += -a[i].y;
1104            sa[7] += a[i].x;
1105
1106            sa[8] += a[i].x;
1107            sa[9] += -a[i].y;
1108            sa[10] += 1;
1109            sa[11] += 0;
1110
1111            sa[12] += a[i].y;
1112            sa[13] += a[i].x;
1113            sa[14] += 0;
1114            sa[15] += 1;
1115
1116            sb[0] += a[i].x*b[i].x + a[i].y*b[i].y;
1117            sb[1] += a[i].x*b[i].y - a[i].y*b[i].x;
1118            sb[2] += b[i].x;
1119            sb[3] += b[i].y;
1120        }
1121
1122        cvSolve( &A, &B, &MM, CV_SVD );
1123
1124        om[0] = om[4] = m[0];
1125        om[1] = -m[1];
1126        om[3] = m[1];
1127        om[2] = m[2];
1128        om[5] = m[3];
1129    }
1130}
1131
1132
1133CV_IMPL int
1134cvEstimateRigidTransform( const CvArr* _A, const CvArr* _B, CvMat* _M, int full_affine )
1135{
1136    int result = 0;
1137
1138    const int COUNT = 15;
1139    const int WIDTH = 160, HEIGHT = 120;
1140    const int RANSAC_MAX_ITERS = 100;
1141    const int RANSAC_SIZE0 = 3;
1142    const double MIN_TRIANGLE_SIDE = 20;
1143    const double RANSAC_GOOD_RATIO = 0.5;
1144
1145    int allocated = 1;
1146    CvMat *sA = 0, *sB = 0;
1147    CvPoint2D32f *pA = 0, *pB = 0;
1148    int* good_idx = 0;
1149    char *status = 0;
1150    CvMat* gray = 0;
1151
1152    CV_FUNCNAME( "cvEstimateRigidTransform" );
1153
1154    __BEGIN__;
1155
1156    CvMat stubA, *A;
1157    CvMat stubB, *B;
1158    CvSize sz0, sz1;
1159    int cn, equal_sizes;
1160    int i, j, k, k1;
1161    int count_x, count_y, count;
1162    double scale = 1;
1163    CvRNG rng = cvRNG(-1);
1164    double m[6]={0};
1165    CvMat M = cvMat( 2, 3, CV_64F, m );
1166    int good_count = 0;
1167
1168    CV_CALL( A = cvGetMat( _A, &stubA ));
1169    CV_CALL( B = cvGetMat( _B, &stubB ));
1170
1171    if( !CV_IS_MAT(_M) )
1172        CV_ERROR( _M ? CV_StsBadArg : CV_StsNullPtr, "Output parameter M is not a valid matrix" );
1173
1174    if( !CV_ARE_SIZES_EQ( A, B ) )
1175        CV_ERROR( CV_StsUnmatchedSizes, "Both input images must have the same size" );
1176
1177    if( !CV_ARE_TYPES_EQ( A, B ) )
1178        CV_ERROR( CV_StsUnmatchedFormats, "Both input images must have the same data type" );
1179
1180    if( CV_MAT_TYPE(A->type) == CV_8UC1 || CV_MAT_TYPE(A->type) == CV_8UC3 )
1181    {
1182        cn = CV_MAT_CN(A->type);
1183        sz0 = cvGetSize(A);
1184        sz1 = cvSize(WIDTH, HEIGHT);
1185
1186        scale = MAX( (double)sz1.width/sz0.width, (double)sz1.height/sz0.height );
1187        scale = MIN( scale, 1. );
1188        sz1.width = cvRound( sz0.width * scale );
1189        sz1.height = cvRound( sz0.height * scale );
1190
1191        equal_sizes = sz1.width == sz0.width && sz1.height == sz0.height;
1192
1193        if( !equal_sizes || cn != 1 )
1194        {
1195            CV_CALL( sA = cvCreateMat( sz1.height, sz1.width, CV_8UC1 ));
1196            CV_CALL( sB = cvCreateMat( sz1.height, sz1.width, CV_8UC1 ));
1197
1198            if( !equal_sizes && cn != 1 )
1199                CV_CALL( gray = cvCreateMat( sz0.height, sz0.width, CV_8UC1 ));
1200
1201            if( gray )
1202            {
1203                cvCvtColor( A, gray, CV_BGR2GRAY );
1204                cvResize( gray, sA, CV_INTER_AREA );
1205                cvCvtColor( B, gray, CV_BGR2GRAY );
1206                cvResize( gray, sB, CV_INTER_AREA );
1207            }
1208            else if( cn == 1 )
1209            {
1210                cvResize( gray, sA, CV_INTER_AREA );
1211                cvResize( gray, sB, CV_INTER_AREA );
1212            }
1213            else
1214            {
1215                cvCvtColor( A, gray, CV_BGR2GRAY );
1216                cvResize( gray, sA, CV_INTER_AREA );
1217                cvCvtColor( B, gray, CV_BGR2GRAY );
1218            }
1219
1220            cvReleaseMat( &gray );
1221            A = sA;
1222            B = sB;
1223        }
1224
1225        count_y = COUNT;
1226        count_x = cvRound((double)COUNT*sz1.width/sz1.height);
1227        count = count_x * count_y;
1228
1229        CV_CALL( pA = (CvPoint2D32f*)cvAlloc( count*sizeof(pA[0]) ));
1230        CV_CALL( pB = (CvPoint2D32f*)cvAlloc( count*sizeof(pB[0]) ));
1231        CV_CALL( status = (char*)cvAlloc( count*sizeof(status[0]) ));
1232
1233        for( i = 0, k = 0; i < count_y; i++ )
1234            for( j = 0; j < count_x; j++, k++ )
1235            {
1236                pA[k].x = (j+0.5f)*sz1.width/count_x;
1237                pA[k].y = (i+0.5f)*sz1.height/count_y;
1238            }
1239
1240        // find the corresponding points in B
1241        cvCalcOpticalFlowPyrLK( A, B, 0, 0, pA, pB, count, cvSize(10,10), 3,
1242                                status, 0, cvTermCriteria(CV_TERMCRIT_ITER,40,0.1), 0 );
1243
1244        // repack the remained points
1245        for( i = 0, k = 0; i < count; i++ )
1246            if( status[i] )
1247            {
1248                if( i > k )
1249                {
1250                    pA[k] = pA[i];
1251                    pB[k] = pB[i];
1252                }
1253                k++;
1254            }
1255
1256        count = k;
1257    }
1258    else if( CV_MAT_TYPE(A->type) == CV_32FC2 || CV_MAT_TYPE(A->type) == CV_32SC2 )
1259    {
1260        count = A->cols*A->rows;
1261
1262        if( CV_IS_MAT_CONT(A->type & B->type) && CV_MAT_TYPE(A->type) == CV_32FC2 )
1263        {
1264            pA = (CvPoint2D32f*)A->data.ptr;
1265            pB = (CvPoint2D32f*)B->data.ptr;
1266            allocated = 0;
1267        }
1268        else
1269        {
1270            CvMat _pA, _pB;
1271
1272            CV_CALL( pA = (CvPoint2D32f*)cvAlloc( count*sizeof(pA[0]) ));
1273            CV_CALL( pB = (CvPoint2D32f*)cvAlloc( count*sizeof(pB[0]) ));
1274            _pA = cvMat( A->rows, A->cols, CV_32FC2, pA );
1275            _pB = cvMat( B->rows, B->cols, CV_32FC2, pB );
1276            cvConvert( A, &_pA );
1277            cvConvert( B, &_pB );
1278        }
1279    }
1280    else
1281        CV_ERROR( CV_StsUnsupportedFormat, "Both input images must have either 8uC1 or 8uC3 type" );
1282
1283    CV_CALL( good_idx = (int*)cvAlloc( count*sizeof(good_idx[0]) ));
1284
1285    if( count < RANSAC_SIZE0 )
1286        EXIT;
1287
1288    // RANSAC stuff:
1289    // 1. find the consensus
1290    for( k = 0; k < RANSAC_MAX_ITERS; k++ )
1291    {
1292        int idx[RANSAC_SIZE0];
1293        CvPoint2D32f a[3];
1294        CvPoint2D32f b[3];
1295
1296        memset( a, 0, sizeof(a) );
1297        memset( b, 0, sizeof(b) );
1298
1299        // choose random 3 non-complanar points from A & B
1300        for( i = 0; i < RANSAC_SIZE0; i++ )
1301        {
1302            for( k1 = 0; k1 < RANSAC_MAX_ITERS; k1++ )
1303            {
1304                idx[i] = cvRandInt(&rng) % count;
1305
1306                for( j = 0; j < i; j++ )
1307                {
1308                    if( idx[j] == idx[i] )
1309                        break;
1310                    // check that the points are not very close one each other
1311                    if( fabs(pA[idx[i]].x - pA[idx[j]].x) +
1312                        fabs(pA[idx[i]].y - pA[idx[j]].y) < MIN_TRIANGLE_SIDE )
1313                        break;
1314                    if( fabs(pB[idx[i]].x - pB[idx[j]].x) +
1315                        fabs(pB[idx[i]].y - pB[idx[j]].y) < MIN_TRIANGLE_SIDE )
1316                        break;
1317                }
1318
1319                if( j < i )
1320                    continue;
1321
1322                if( i+1 == RANSAC_SIZE0 )
1323                {
1324                    // additional check for non-complanar vectors
1325                    a[0] = pA[idx[0]];
1326                    a[1] = pA[idx[1]];
1327                    a[2] = pA[idx[2]];
1328
1329                    b[0] = pB[idx[0]];
1330                    b[1] = pB[idx[1]];
1331                    b[2] = pB[idx[2]];
1332
1333                    if( fabs((a[1].x - a[0].x)*(a[2].y - a[0].y) - (a[1].y - a[0].y)*(a[2].x - a[0].x)) < 1 ||
1334                        fabs((b[1].x - b[0].x)*(b[2].y - b[0].y) - (b[1].y - b[0].y)*(b[2].x - b[0].x)) < 1 )
1335                        continue;
1336                }
1337                break;
1338            }
1339
1340            if( k1 >= RANSAC_MAX_ITERS )
1341                break;
1342        }
1343
1344        if( i < RANSAC_SIZE0 )
1345            continue;
1346
1347        // estimate the transformation using 3 points
1348        icvGetRTMatrix( a, b, 3, &M, full_affine );
1349
1350        for( i = 0, good_count = 0; i < count; i++ )
1351        {
1352            if( fabs( m[0]*pA[i].x + m[1]*pA[i].y + m[2] - pB[i].x ) +
1353                fabs( m[3]*pA[i].x + m[4]*pA[i].y + m[5] - pB[i].y ) < 8 )
1354                good_idx[good_count++] = i;
1355        }
1356
1357        if( good_count >= count*RANSAC_GOOD_RATIO )
1358            break;
1359    }
1360
1361    if( k >= RANSAC_MAX_ITERS )
1362        EXIT;
1363
1364    if( good_count < count )
1365    {
1366        for( i = 0; i < good_count; i++ )
1367        {
1368            j = good_idx[i];
1369            pA[i] = pA[j];
1370            pB[i] = pB[j];
1371        }
1372    }
1373
1374    icvGetRTMatrix( pA, pB, good_count, &M, full_affine );
1375    m[2] /= scale;
1376    m[5] /= scale;
1377    CV_CALL( cvConvert( &M, _M ));
1378    result = 1;
1379
1380    __END__;
1381
1382    cvReleaseMat( &sA );
1383    cvReleaseMat( &sB );
1384    cvFree( &pA );
1385    cvFree( &pB );
1386    cvFree( &status );
1387    cvFree( &good_idx );
1388    cvReleaseMat( &gray );
1389
1390    return result;
1391}
1392
1393
1394/* End of file. */
1395