1 /*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 /* $Id: db_utilities_camera.h,v 1.3 2011/06/17 14:03:31 mbansal Exp $ */
18
19 #ifndef DB_UTILITIES_CAMERA
20 #define DB_UTILITIES_CAMERA
21
22 #include "db_utilities.h"
23
24
25
26 /*****************************************************************
27 * Lean and mean begins here *
28 *****************************************************************/
29 /*!
30 * \defgroup LMCamera (LM) Camera Utilities
31 */
32 /*\{*/
33
34 #include "db_utilities.h"
35
36 #define DB_RADDISTMODE_BOUGEUT 4
37 #define DB_RADDISTMODE_2NDORDER 5
38 #define DB_RADDISTMODE_IDENTITY 6
39
40 /*!
41 Give reasonable guess of the calibration matrix for normalization purposes.
42 Use real K matrix when doing real geometry.
43 focal length = (w+h)/2.0*f_correction.
44 \param K calibration matrix (out)
45 \param Kinv inverse of K (out)
46 \param im_width image width
47 \param im_height image height
48 \param f_correction focal length correction factor
49 \param field set to 1 if this is a field image (fy = fx/2)
50 \return K(3x3) intrinsic calibration matrix
51 */
52 DB_API void db_Approx3DCalMat(double K[9],double Kinv[9],int im_width,int im_height,double f_correction=1.0,int field=0);
53
54 /*!
55 Make a 2x2 identity matrix
56 */
db_Identity2x2(double A[4])57 void inline db_Identity2x2(double A[4])
58 {
59 A[0]=1;A[1]=0;
60 A[2]=0;A[3]=1;
61 }
62 /*!
63 Make a 3x3 identity matrix
64 */
db_Identity3x3(double A[9])65 void inline db_Identity3x3(double A[9])
66 {
67 A[0]=1;A[1]=0;A[2]=0;
68 A[3]=0;A[4]=1;A[5]=0;
69 A[6]=0;A[7]=0;A[8]=1;
70 }
71 /*!
72 Invert intrinsic calibration matrix K(3x3)
73 If fx or fy is 0, I is returned.
74 */
db_InvertCalibrationMatrix(double Kinv[9],const double K[9])75 void inline db_InvertCalibrationMatrix(double Kinv[9],const double K[9])
76 {
77 double a,b,c,d,e,f,ainv,dinv,adinv;
78
79 a=K[0];b=K[1];c=K[2];d=K[4];e=K[5];f=K[8];
80 if((a==0.0)||(d==0.0)) db_Identity3x3(Kinv);
81 else
82 {
83 Kinv[3]=0.0;
84 Kinv[6]=0.0;
85 Kinv[7]=0.0;
86 Kinv[8]=1.0;
87
88 ainv=1.0/a;
89 dinv=1.0/d;
90 adinv=ainv*dinv;
91 Kinv[0]=f*ainv;
92 Kinv[1]= -b*f*adinv;
93 Kinv[2]=(b*e-c*d)*adinv;
94 Kinv[4]=f*dinv;
95 Kinv[5]= -e*dinv;
96 }
97 }
98 /*!
99 De-homogenize image point: xd(1:2) = xs(1:2)/xs(3).
100 If xs(3) is 0, xd will become 0
101 \param xd destination point
102 \param xs source point
103 */
db_DeHomogenizeImagePoint(double xd[2],const double xs[3])104 void inline db_DeHomogenizeImagePoint(double xd[2],const double xs[3])
105 {
106 double temp,div;
107
108 temp=xs[2];
109 if(temp!=0)
110 {
111 div=1.0/temp;
112 xd[0]=xs[0]*div;xd[1]=xs[1]*div;
113 }
114 else
115 {
116 xd[0]=0.0;xd[1]=0.0;
117 }
118 }
119
120
121 /*!
122 Orthonormalize 3D rotation R
123 */
db_OrthonormalizeRotation(double R[9])124 inline void db_OrthonormalizeRotation(double R[9])
125 {
126 double s,mult;
127 /*Normalize first vector*/
128 s=db_sqr(R[0])+db_sqr(R[1])+db_sqr(R[2]);
129 mult=sqrt(1.0/(s?s:1));
130 R[0]*=mult; R[1]*=mult; R[2]*=mult;
131 /*Subtract scalar product from second vector*/
132 s=R[0]*R[3]+R[1]*R[4]+R[2]*R[5];
133 R[3]-=s*R[0]; R[4]-=s*R[1]; R[5]-=s*R[2];
134 /*Normalize second vector*/
135 s=db_sqr(R[3])+db_sqr(R[4])+db_sqr(R[5]);
136 mult=sqrt(1.0/(s?s:1));
137 R[3]*=mult; R[4]*=mult; R[5]*=mult;
138 /*Get third vector by vector product*/
139 R[6]=R[1]*R[5]-R[4]*R[2];
140 R[7]=R[2]*R[3]-R[5]*R[0];
141 R[8]=R[0]*R[4]-R[3]*R[1];
142 }
143 /*!
144 Update a rotation with the update dx=[sin(phi) sin(ohm) sin(kap)]
145 */
db_UpdateRotation(double R_p_dx[9],double R[9],const double dx[3])146 inline void db_UpdateRotation(double R_p_dx[9],double R[9],const double dx[3])
147 {
148 double R_temp[9];
149 /*Update rotation*/
150 db_IncrementalRotationMatrix(R_temp,dx);
151 db_Multiply3x3_3x3(R_p_dx,R_temp,R);
152 }
153 /*!
154 Compute xp = Hx for inhomogenous image points.
155 */
db_ImageHomographyInhomogenous(double xp[2],const double H[9],const double x[2])156 inline void db_ImageHomographyInhomogenous(double xp[2],const double H[9],const double x[2])
157 {
158 double x3,m;
159
160 x3=H[6]*x[0]+H[7]*x[1]+H[8];
161 if(x3!=0.0)
162 {
163 m=1.0/x3;
164 xp[0]=m*(H[0]*x[0]+H[1]*x[1]+H[2]);
165 xp[1]=m*(H[3]*x[0]+H[4]*x[1]+H[5]);
166 }
167 else
168 {
169 xp[0]=xp[1]=0.0;
170 }
171 }
db_FocalFromCamRotFocalHomography(const double H[9])172 inline double db_FocalFromCamRotFocalHomography(const double H[9])
173 {
174 double k1,k2;
175
176 k1=db_sqr(H[2])+db_sqr(H[5]);
177 k2=db_sqr(H[6])+db_sqr(H[7]);
178 if(k1>=k2)
179 {
180 return(db_SafeSqrt(db_SafeDivision(k1,1.0-db_sqr(H[8]))));
181 }
182 else
183 {
184 return(db_SafeSqrt(db_SafeDivision(1.0-db_sqr(H[8]),k2)));
185 }
186 }
187
db_FocalAndRotFromCamRotFocalHomography(double R[9],const double H[9])188 inline double db_FocalAndRotFromCamRotFocalHomography(double R[9],const double H[9])
189 {
190 double back,fi;
191
192 back=db_FocalFromCamRotFocalHomography(H);
193 fi=db_SafeReciprocal(back);
194 R[0]=H[0]; R[1]=H[1]; R[2]=fi*H[2];
195 R[3]=H[3]; R[4]=H[4]; R[5]=fi*H[5];
196 R[6]=back*H[6]; R[7]=back*H[7]; R[8]=H[8];
197 return(back);
198 }
199 /*!
200 Compute Jacobian at zero of three coordinates dR*x with
201 respect to the update dR([sin(phi) sin(ohm) sin(kap)]) given x.
202
203 The Jacobian at zero of the homogenous coordinates with respect to
204 [sin(phi) sin(ohm) sin(kap)] is
205 \code
206 [-rx2 0 rx1 ]
207 [ 0 rx2 -rx0 ]
208 [ rx0 -rx1 0 ].
209 \endcode
210
211 */
db_JacobianOfRotatedPointStride(double J[9],const double x[3],int stride)212 inline void db_JacobianOfRotatedPointStride(double J[9],const double x[3],int stride)
213 {
214 /*The Jacobian at zero of the homogenous coordinates with respect to
215 [sin(phi) sin(ohm) sin(kap)] is
216 [-rx2 0 rx1 ]
217 [ 0 rx2 -rx0 ]
218 [ rx0 -rx1 0 ]*/
219
220 J[0]= -x[stride<<1];
221 J[1]=0;
222 J[2]= x[stride];
223 J[3]=0;
224 J[4]= x[stride<<1];
225 J[5]= -x[0];
226 J[6]= x[0];
227 J[7]= -x[stride];
228 J[8]=0;
229 }
230 /*!
231 Invert an affine (if possible)
232 \param Hinv inverted matrix
233 \param H input matrix
234 \return true if success and false if matrix is ill-conditioned (det < 1e-7)
235 */
db_InvertAffineTransform(double Hinv[9],const double H[9])236 inline bool db_InvertAffineTransform(double Hinv[9],const double H[9])
237 {
238 double det=H[0]*H[4]-H[3]*H[1];
239 if (det<1e-7)
240 {
241 db_Copy9(Hinv,H);
242 return false;
243 }
244 else
245 {
246 Hinv[0]=H[4]/det;
247 Hinv[1]=-H[1]/det;
248 Hinv[3]=-H[3]/det;
249 Hinv[4]=H[0]/det;
250 Hinv[2]= -Hinv[0]*H[2]-Hinv[1]*H[5];
251 Hinv[5]= -Hinv[3]*H[2]-Hinv[4]*H[5];
252 }
253 return true;
254 }
255
256 /*!
257 Update of upper 2x2 is multiplication by
258 \code
259 [s 0][ cos(theta) sin(theta)]
260 [0 s][-sin(theta) cos(theta)]
261 \endcode
262 */
db_MultiplyScaleOntoImageHomography(double H[9],double s)263 inline void db_MultiplyScaleOntoImageHomography(double H[9],double s)
264 {
265
266 H[0]*=s;
267 H[1]*=s;
268 H[3]*=s;
269 H[4]*=s;
270 }
271 /*!
272 Update of upper 2x2 is multiplication by
273 \code
274 [s 0][ cos(theta) sin(theta)]
275 [0 s][-sin(theta) cos(theta)]
276 \endcode
277 */
db_MultiplyRotationOntoImageHomography(double H[9],double theta)278 inline void db_MultiplyRotationOntoImageHomography(double H[9],double theta)
279 {
280 double c,s,H0,H1;
281
282
283 c=cos(theta);
284 s=db_SafeSqrt(1.0-db_sqr(c));
285 H0= c*H[0]+s*H[3];
286 H[3]= -s*H[0]+c*H[3];
287 H[0]=H0;
288 H1=c*H[1]+s*H[4];
289 H[4]= -s*H[1]+c*H[4];
290 H[1]=H1;
291 }
292
db_UpdateImageHomographyAffine(double H_p_dx[9],const double H[9],const double dx[6])293 inline void db_UpdateImageHomographyAffine(double H_p_dx[9],const double H[9],const double dx[6])
294 {
295 db_AddVectors6(H_p_dx,H,dx);
296 db_Copy3(H_p_dx+6,H+6);
297 }
298
db_UpdateImageHomographyProjective(double H_p_dx[9],const double H[9],const double dx[8],int frozen_coord)299 inline void db_UpdateImageHomographyProjective(double H_p_dx[9],const double H[9],const double dx[8],int frozen_coord)
300 {
301 int i,j;
302
303 for(j=0,i=0;i<9;i++)
304 {
305 if(i!=frozen_coord)
306 {
307 H_p_dx[i]=H[i]+dx[j];
308 j++;
309 }
310 else H_p_dx[i]=H[i];
311 }
312 }
313
db_UpdateRotFocalHomography(double H_p_dx[9],const double H[9],const double dx[4])314 inline void db_UpdateRotFocalHomography(double H_p_dx[9],const double H[9],const double dx[4])
315 {
316 double f,fp,fpi;
317 double R[9],dR[9];
318
319 /*Updated matrix is diag(f+df,f+df)*dR*R*diag(1/(f+df),1/(f+df),1)*/
320 f=db_FocalAndRotFromCamRotFocalHomography(R,H);
321 db_IncrementalRotationMatrix(dR,dx);
322 db_Multiply3x3_3x3(H_p_dx,dR,R);
323 fp=f+dx[3];
324 fpi=db_SafeReciprocal(fp);
325 H_p_dx[2]*=fp;
326 H_p_dx[5]*=fp;
327 H_p_dx[6]*=fpi;
328 H_p_dx[7]*=fpi;
329 }
330
331 /*\}*/
332 #endif /* DB_UTILITIES_CAMERA */
333