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41 
42 #include "_cv.h"
43 
44 static CvStatus
icvUnDistort_8u_CnR(const uchar * src,int srcstep,uchar * dst,int dststep,CvSize size,const float * intrinsic_matrix,const float * dist_coeffs,int cn)45 icvUnDistort_8u_CnR( const uchar* src, int srcstep,
46                      uchar* dst, int dststep, CvSize size,
47                      const float* intrinsic_matrix,
48                      const float* dist_coeffs, int cn )
49 {
50     int u, v, i;
51     float u0 = intrinsic_matrix[2], v0 = intrinsic_matrix[5];
52     float x0 = (size.width-1)*0.5f, y0 = (size.height-1)*0.5f;
53     float fx = intrinsic_matrix[0], fy = intrinsic_matrix[4];
54     float ifx = 1.f/fx, ify = 1.f/fy;
55     float k1 = dist_coeffs[0], k2 = dist_coeffs[1], k3 = dist_coeffs[4];
56     float p1 = dist_coeffs[2], p2 = dist_coeffs[3];
57 
58     srcstep /= sizeof(src[0]);
59     dststep /= sizeof(dst[0]);
60 
61     for( v = 0; v < size.height; v++, dst += dststep )
62     {
63         float y = (v - v0)*ify, y2 = y*y;
64 
65         for( u = 0; u < size.width; u++ )
66         {
67             float x = (u - u0)*ifx, x2 = x*x, r2 = x2 + y2, _2xy = 2*x*y;
68             float kr = 1 + ((k3*r2 + k2)*r2 + k1)*r2;
69             float _x = fx*(x*kr + p1*_2xy + p2*(r2 + 2*x2)) + x0;
70             float _y = fy*(y*kr + p1*(r2 + 2*y2) + p2*_2xy) + y0;
71             int ix = cvFloor(_x), iy = cvFloor(_y);
72 
73             if( (unsigned)iy < (unsigned)(size.height - 1) &&
74                 (unsigned)ix < (unsigned)(size.width - 1) )
75             {
76                 const uchar* ptr = src + iy*srcstep + ix*cn;
77                 _x -= ix; _y -= iy;
78                 for( i = 0; i < cn; i++ )
79                 {
80                     float t0 = CV_8TO32F(ptr[i]), t1 = CV_8TO32F(ptr[i+srcstep]);
81                     t0 += _x*(CV_8TO32F(ptr[i+cn]) - t0);
82                     t1 += _x*(CV_8TO32F(ptr[i + srcstep + cn]) - t1);
83                     dst[u*cn + i] = (uchar)cvRound(t0 + _y*(t1 - t0));
84                 }
85             }
86             else
87             {
88                 for( i = 0; i < cn; i++ )
89                     dst[u*cn + i] = 0;
90             }
91 
92         }
93     }
94 
95     return CV_OK;
96 }
97 
98 
99 icvUndistortGetSize_t icvUndistortGetSize_p = 0;
100 icvCreateMapCameraUndistort_32f_C1R_t icvCreateMapCameraUndistort_32f_C1R_p = 0;
101 icvUndistortRadial_8u_C1R_t icvUndistortRadial_8u_C1R_p = 0;
102 icvUndistortRadial_8u_C3R_t icvUndistortRadial_8u_C3R_p = 0;
103 
104 typedef CvStatus (CV_STDCALL * CvUndistortRadialIPPFunc)
105     ( const void* pSrc, int srcStep, void* pDst, int dstStep, CvSize roiSize,
106       float fx, float fy, float cx, float cy, float k1, float k2, uchar *pBuffer );
107 
108 CV_IMPL void
cvUndistort2(const CvArr * _src,CvArr * _dst,const CvMat * A,const CvMat * dist_coeffs)109 cvUndistort2( const CvArr* _src, CvArr* _dst, const CvMat* A, const CvMat* dist_coeffs )
110 {
111     static int inittab = 0;
112 
113     CV_FUNCNAME( "cvUndistort2" );
114 
115     __BEGIN__;
116 
117     float a[9], k[5]={0,0,0,0,0};
118     int coi1 = 0, coi2 = 0;
119     CvMat srcstub, *src = (CvMat*)_src;
120     CvMat dststub, *dst = (CvMat*)_dst;
121     CvMat _a = cvMat( 3, 3, CV_32F, a ), _k;
122     int cn, src_step, dst_step;
123     CvSize size;
124 
125     if( !inittab )
126     {
127         icvInitLinearCoeffTab();
128         icvInitCubicCoeffTab();
129         inittab = 1;
130     }
131 
132     CV_CALL( src = cvGetMat( src, &srcstub, &coi1 ));
133     CV_CALL( dst = cvGetMat( dst, &dststub, &coi2 ));
134 
135     if( coi1 != 0 || coi2 != 0 )
136         CV_ERROR( CV_BadCOI, "The function does not support COI" );
137 
138     if( CV_MAT_DEPTH(src->type) != CV_8U )
139         CV_ERROR( CV_StsUnsupportedFormat, "Only 8-bit images are supported" );
140 
141     if( src->data.ptr == dst->data.ptr )
142         CV_ERROR( CV_StsNotImplemented, "In-place undistortion is not implemented" );
143 
144     if( !CV_ARE_TYPES_EQ( src, dst ))
145         CV_ERROR( CV_StsUnmatchedFormats, "" );
146 
147     if( !CV_ARE_SIZES_EQ( src, dst ))
148         CV_ERROR( CV_StsUnmatchedSizes, "" );
149 
150     if( !CV_IS_MAT(A) || A->rows != 3 || A->cols != 3  ||
151         (CV_MAT_TYPE(A->type) != CV_32FC1 && CV_MAT_TYPE(A->type) != CV_64FC1) )
152         CV_ERROR( CV_StsBadArg, "Intrinsic matrix must be a valid 3x3 floating-point matrix" );
153 
154     if( !CV_IS_MAT(dist_coeffs) || (dist_coeffs->rows != 1 && dist_coeffs->cols != 1) ||
155         (dist_coeffs->rows*dist_coeffs->cols*CV_MAT_CN(dist_coeffs->type) != 4 &&
156         dist_coeffs->rows*dist_coeffs->cols*CV_MAT_CN(dist_coeffs->type) != 5) ||
157         (CV_MAT_DEPTH(dist_coeffs->type) != CV_64F &&
158         CV_MAT_DEPTH(dist_coeffs->type) != CV_32F) )
159         CV_ERROR( CV_StsBadArg,
160             "Distortion coefficients must be 1x4, 4x1, 1x5 or 5x1 floating-point vector" );
161 
162     cvConvert( A, &_a );
163     _k = cvMat( dist_coeffs->rows, dist_coeffs->cols,
164                 CV_MAKETYPE(CV_32F, CV_MAT_CN(dist_coeffs->type)), k );
165     cvConvert( dist_coeffs, &_k );
166 
167     cn = CV_MAT_CN(src->type);
168     size = cvGetMatSize(src);
169     src_step = src->step ? src->step : CV_STUB_STEP;
170     dst_step = dst->step ? dst->step : CV_STUB_STEP;
171 
172     icvUnDistort_8u_CnR( src->data.ptr, src_step,
173         dst->data.ptr, dst_step, size, a, k, cn );
174 
175     __END__;
176 }
177 
178 
179 CV_IMPL void
cvInitUndistortMap(const CvMat * A,const CvMat * dist_coeffs,CvArr * mapxarr,CvArr * mapyarr)180 cvInitUndistortMap( const CvMat* A, const CvMat* dist_coeffs,
181                     CvArr* mapxarr, CvArr* mapyarr )
182 {
183     CV_FUNCNAME( "cvInitUndistortMap" );
184 
185     __BEGIN__;
186 
187     float a[9], k[5]={0,0,0,0,0};
188     int coi1 = 0, coi2 = 0;
189     CvMat mapxstub, *_mapx = (CvMat*)mapxarr;
190     CvMat mapystub, *_mapy = (CvMat*)mapyarr;
191     CvMat _a = cvMat( 3, 3, CV_32F, a ), _k;
192     int u, v;
193     float u0, v0, fx, fy, ifx, ify, x0, y0, k1, k2, k3, p1, p2;
194     CvSize size;
195 
196     CV_CALL( _mapx = cvGetMat( _mapx, &mapxstub, &coi1 ));
197     CV_CALL( _mapy = cvGetMat( _mapy, &mapystub, &coi2 ));
198 
199     if( coi1 != 0 || coi2 != 0 )
200         CV_ERROR( CV_BadCOI, "The function does not support COI" );
201 
202     if( CV_MAT_TYPE(_mapx->type) != CV_32FC1 )
203         CV_ERROR( CV_StsUnsupportedFormat, "Both maps must have 32fC1 type" );
204 
205     if( !CV_ARE_TYPES_EQ( _mapx, _mapy ))
206         CV_ERROR( CV_StsUnmatchedFormats, "" );
207 
208     if( !CV_ARE_SIZES_EQ( _mapx, _mapy ))
209         CV_ERROR( CV_StsUnmatchedSizes, "" );
210 
211     size = cvGetMatSize(_mapx);
212 
213     if( !CV_IS_MAT(A) || A->rows != 3 || A->cols != 3  ||
214         (CV_MAT_TYPE(A->type) != CV_32FC1 && CV_MAT_TYPE(A->type) != CV_64FC1) )
215         CV_ERROR( CV_StsBadArg, "Intrinsic matrix must be a valid 3x3 floating-point matrix" );
216 
217     if( !CV_IS_MAT(dist_coeffs) || (dist_coeffs->rows != 1 && dist_coeffs->cols != 1) ||
218         (dist_coeffs->rows*dist_coeffs->cols*CV_MAT_CN(dist_coeffs->type) != 4 &&
219         dist_coeffs->rows*dist_coeffs->cols*CV_MAT_CN(dist_coeffs->type) != 5) ||
220         (CV_MAT_DEPTH(dist_coeffs->type) != CV_64F &&
221         CV_MAT_DEPTH(dist_coeffs->type) != CV_32F) )
222         CV_ERROR( CV_StsBadArg,
223             "Distortion coefficients must be 1x4, 4x1, 1x5 or 5x1 floating-point vector" );
224 
225     cvConvert( A, &_a );
226     _k = cvMat( dist_coeffs->rows, dist_coeffs->cols,
227                 CV_MAKETYPE(CV_32F, CV_MAT_CN(dist_coeffs->type)), k );
228     cvConvert( dist_coeffs, &_k );
229 
230     u0 = a[2]; v0 = a[5];
231     fx = a[0]; fy = a[4];
232     ifx = 1.f/fx; ify = 1.f/fy;
233     k1 = k[0]; k2 = k[1]; k3 = k[4];
234     p1 = k[2]; p2 = k[3];
235     x0 = (size.width-1)*0.5f;
236     y0 = (size.height-1)*0.5f;
237 
238     for( v = 0; v < size.height; v++ )
239     {
240         float* mapx = (float*)(_mapx->data.ptr + _mapx->step*v);
241         float* mapy = (float*)(_mapy->data.ptr + _mapy->step*v);
242         float y = (v - v0)*ify, y2 = y*y;
243 
244         for( u = 0; u < size.width; u++ )
245         {
246             float x = (u - u0)*ifx, x2 = x*x, r2 = x2 + y2, _2xy = 2*x*y;
247             double kr = 1 + ((k3*r2 + k2)*r2 + k1)*r2;
248             double _x = fx*(x*kr + p1*_2xy + p2*(r2 + 2*x2)) + x0;
249             double _y = fy*(y*kr + p1*(r2 + 2*y2) + p2*_2xy) + y0;
250             mapx[u] = (float)_x;
251             mapy[u] = (float)_y;
252         }
253     }
254 
255     __END__;
256 }
257 
258 
259 void
cvInitUndistortRectifyMap(const CvMat * A,const CvMat * distCoeffs,const CvMat * R,const CvMat * Ar,CvArr * mapxarr,CvArr * mapyarr)260 cvInitUndistortRectifyMap( const CvMat* A, const CvMat* distCoeffs,
261     const CvMat *R, const CvMat* Ar, CvArr* mapxarr, CvArr* mapyarr )
262 {
263     CV_FUNCNAME( "cvInitUndistortMap" );
264 
265     __BEGIN__;
266 
267     double a[9], ar[9], r[9], ir[9], k[5]={0,0,0,0,0};
268     int coi1 = 0, coi2 = 0;
269     CvMat mapxstub, *_mapx = (CvMat*)mapxarr;
270     CvMat mapystub, *_mapy = (CvMat*)mapyarr;
271     CvMat _a = cvMat( 3, 3, CV_64F, a );
272     CvMat _k = cvMat( 4, 1, CV_64F, k );
273     CvMat _ar = cvMat( 3, 3, CV_64F, ar );
274     CvMat _r = cvMat( 3, 3, CV_64F, r );
275     CvMat _ir = cvMat( 3, 3, CV_64F, ir );
276     int i, j;
277     double fx, fy, u0, v0, k1, k2, k3, p1, p2;
278     CvSize size;
279 
280     CV_CALL( _mapx = cvGetMat( _mapx, &mapxstub, &coi1 ));
281     CV_CALL( _mapy = cvGetMat( _mapy, &mapystub, &coi2 ));
282 
283     if( coi1 != 0 || coi2 != 0 )
284         CV_ERROR( CV_BadCOI, "The function does not support COI" );
285 
286     if( CV_MAT_TYPE(_mapx->type) != CV_32FC1 )
287         CV_ERROR( CV_StsUnsupportedFormat, "Both maps must have 32fC1 type" );
288 
289     if( !CV_ARE_TYPES_EQ( _mapx, _mapy ))
290         CV_ERROR( CV_StsUnmatchedFormats, "" );
291 
292     if( !CV_ARE_SIZES_EQ( _mapx, _mapy ))
293         CV_ERROR( CV_StsUnmatchedSizes, "" );
294 
295     if( A )
296     {
297         if( !CV_IS_MAT(A) || A->rows != 3 || A->cols != 3  ||
298             (CV_MAT_TYPE(A->type) != CV_32FC1 && CV_MAT_TYPE(A->type) != CV_64FC1) )
299             CV_ERROR( CV_StsBadArg, "Intrinsic matrix must be a valid 3x3 floating-point matrix" );
300         cvConvert( A, &_a );
301     }
302     else
303         cvSetIdentity( &_a );
304 
305     if( Ar )
306     {
307         CvMat Ar33;
308         if( !CV_IS_MAT(Ar) || Ar->rows != 3 || (Ar->cols != 3 && Ar->cols != 4) ||
309             (CV_MAT_TYPE(Ar->type) != CV_32FC1 && CV_MAT_TYPE(Ar->type) != CV_64FC1) )
310             CV_ERROR( CV_StsBadArg, "The new intrinsic matrix must be a valid 3x3 floating-point matrix" );
311         cvGetCols( Ar, &Ar33, 0, 3 );
312         cvConvert( &Ar33, &_ar );
313     }
314     else
315         cvSetIdentity( &_ar );
316 
317     if( !CV_IS_MAT(R) || R->rows != 3 || R->cols != 3  ||
318         (CV_MAT_TYPE(R->type) != CV_32FC1 && CV_MAT_TYPE(R->type) != CV_64FC1) )
319         CV_ERROR( CV_StsBadArg, "Rotaion/homography matrix must be a valid 3x3 floating-point matrix" );
320 
321     if( distCoeffs )
322     {
323         CV_ASSERT( CV_IS_MAT(distCoeffs) &&
324             (distCoeffs->rows == 1 || distCoeffs->cols == 1) &&
325             (distCoeffs->rows*distCoeffs->cols*CV_MAT_CN(distCoeffs->type) == 4 ||
326             distCoeffs->rows*distCoeffs->cols*CV_MAT_CN(distCoeffs->type) == 5) &&
327             (CV_MAT_DEPTH(distCoeffs->type) == CV_64F ||
328             CV_MAT_DEPTH(distCoeffs->type) == CV_32F) );
329         _k = cvMat( distCoeffs->rows, distCoeffs->cols,
330                 CV_MAKETYPE(CV_64F, CV_MAT_CN(distCoeffs->type)), k );
331         cvConvert( distCoeffs, &_k );
332     }
333     else
334         cvZero( &_k );
335 
336     cvConvert( R, &_r );    // rectification matrix
337     cvMatMul( &_ar, &_r, &_r ); // Ar*R
338     cvInvert( &_r, &_ir );  // inverse: R^-1*Ar^-1
339 
340     u0 = a[2]; v0 = a[5];
341     fx = a[0]; fy = a[4];
342     k1 = k[0]; k2 = k[1]; k3 = k[4];
343     p1 = k[2]; p2 = k[3];
344 
345     size = cvGetMatSize(_mapx);
346 
347     for( i = 0; i < size.height; i++ )
348     {
349         float* mapx = (float*)(_mapx->data.ptr + _mapx->step*i);
350         float* mapy = (float*)(_mapy->data.ptr + _mapy->step*i);
351         double _x = i*ir[1] + ir[2], _y = i*ir[4] + ir[5], _w = i*ir[7] + ir[8];
352 
353         for( j = 0; j < size.width; j++, _x += ir[0], _y += ir[3], _w += ir[6] )
354         {
355             double w = 1./_w, x = _x*w, y = _y*w;
356             double x2 = x*x, y2 = y*y;
357             double r2 = x2 + y2, _2xy = 2*x*y;
358             double kr = 1 + ((k3*r2 + k2)*r2 + k1)*r2;
359             double u = fx*(x*kr + p1*_2xy + p2*(r2 + 2*x2)) + u0;
360             double v = fy*(y*kr + p1*(r2 + 2*y2) + p2*_2xy) + v0;
361             mapx[j] = (float)u;
362             mapy[j] = (float)v;
363         }
364     }
365 
366     __END__;
367 }
368 
369 
370 void
cvUndistortPoints(const CvMat * _src,CvMat * _dst,const CvMat * _cameraMatrix,const CvMat * _distCoeffs,const CvMat * _R,const CvMat * _P)371 cvUndistortPoints( const CvMat* _src, CvMat* _dst, const CvMat* _cameraMatrix,
372                    const CvMat* _distCoeffs,
373                    const CvMat* _R, const CvMat* _P )
374 {
375     CV_FUNCNAME( "cvUndistortPoints" );
376 
377     __BEGIN__;
378 
379     double A[3][3], RR[3][3], k[5]={0,0,0,0,0}, fx, fy, ifx, ify, cx, cy;
380     CvMat _A=cvMat(3, 3, CV_64F, A), _Dk;
381     CvMat _RR=cvMat(3, 3, CV_64F, RR);
382     const CvPoint2D32f* srcf;
383     const CvPoint2D64f* srcd;
384     CvPoint2D32f* dstf;
385     CvPoint2D64f* dstd;
386     int stype, dtype;
387     int sstep, dstep;
388     int i, j, n;
389 
390     CV_ASSERT( CV_IS_MAT(_src) && CV_IS_MAT(_dst) &&
391         (_src->rows == 1 || _src->cols == 1) &&
392         (_dst->rows == 1 || _dst->cols == 1) &&
393         CV_ARE_SIZES_EQ(_src, _dst) &&
394         (CV_MAT_TYPE(_src->type) == CV_32FC2 || CV_MAT_TYPE(_src->type) == CV_64FC2) &&
395         (CV_MAT_TYPE(_dst->type) == CV_32FC2 || CV_MAT_TYPE(_dst->type) == CV_64FC2));
396 
397     CV_ASSERT( CV_IS_MAT(_cameraMatrix) && CV_IS_MAT(_distCoeffs) &&
398         _cameraMatrix->rows == 3 && _cameraMatrix->cols == 3 &&
399         (_distCoeffs->rows == 1 || _distCoeffs->cols == 1) &&
400         (_distCoeffs->rows*_distCoeffs->cols == 4 ||
401         _distCoeffs->rows*_distCoeffs->cols == 5) );
402     _Dk = cvMat( _distCoeffs->rows, _distCoeffs->cols,
403         CV_MAKETYPE(CV_64F,CV_MAT_CN(_distCoeffs->type)), k);
404     cvConvert( _cameraMatrix, &_A );
405     cvConvert( _distCoeffs, &_Dk );
406 
407     if( _R )
408     {
409         CV_ASSERT( CV_IS_MAT(_R) && _R->rows == 3 && _R->cols == 3 );
410         cvConvert( _R, &_RR );
411     }
412     else
413         cvSetIdentity(&_RR);
414 
415     if( _P )
416     {
417         double PP[3][3];
418         CvMat _P3x3, _PP=cvMat(3, 3, CV_64F, PP);
419         CV_ASSERT( CV_IS_MAT(_P) && _P->rows == 3 && (_P->cols == 3 || _P->cols == 4));
420         cvConvert( cvGetCols(_P, &_P3x3, 0, 3), &_PP );
421         cvMatMul( &_PP, &_RR, &_RR );
422     }
423 
424     srcf = (const CvPoint2D32f*)_src->data.ptr;
425     srcd = (const CvPoint2D64f*)_src->data.ptr;
426     dstf = (CvPoint2D32f*)_dst->data.ptr;
427     dstd = (CvPoint2D64f*)_dst->data.ptr;
428     stype = CV_MAT_TYPE(_src->type);
429     dtype = CV_MAT_TYPE(_dst->type);
430     sstep = _src->rows == 1 ? 1 : _src->step/CV_ELEM_SIZE(stype);
431     dstep = _dst->rows == 1 ? 1 : _dst->step/CV_ELEM_SIZE(dtype);
432 
433     n = _src->rows + _src->cols - 1;
434 
435     fx = A[0][0];
436     fy = A[1][1];
437     ifx = 1./fx;
438     ify = 1./fy;
439     cx = A[0][2];
440     cy = A[1][2];
441 
442     for( i = 0; i < n; i++ )
443     {
444         double x, y, x0, y0;
445         if( stype == CV_32FC2 )
446         {
447             x = srcf[i*sstep].x;
448             y = srcf[i*sstep].y;
449         }
450         else
451         {
452             x = srcd[i*sstep].x;
453             y = srcd[i*sstep].y;
454         }
455 
456         x0 = x = (x - cx)*ifx;
457         y0 = y = (y - cy)*ify;
458 
459         // compensate distortion iteratively
460         for( j = 0; j < 5; j++ )
461         {
462             double r2 = x*x + y*y;
463             double icdist = 1./(1 + ((k[4]*r2 + k[1])*r2 + k[0])*r2);
464             double deltaX = 2*k[2]*x*y + k[3]*(r2 + 2*x*x);
465             double deltaY = k[2]*(r2 + 2*y*y) + 2*k[3]*x*y;
466             x = (x0 - deltaX)*icdist;
467             y = (y0 - deltaY)*icdist;
468         }
469 
470         double xx = RR[0][0]*x + RR[0][1]*y + RR[0][2];
471         double yy = RR[1][0]*x + RR[1][1]*y + RR[1][2];
472         double ww = 1./(RR[2][0]*x + RR[2][1]*y + RR[2][2]);
473         x = xx*ww;
474         y = yy*ww;
475 
476         if( dtype == CV_32FC2 )
477         {
478             dstf[i*dstep].x = (float)x;
479             dstf[i*dstep].y = (float)y;
480         }
481         else
482         {
483             dstd[i*dstep].x = x;
484             dstd[i*dstep].y = y;
485         }
486     }
487 
488     __END__;
489 }
490 
491 /*  End of file  */
492