Hi,<br>I am bit new to ITK.<br>After compiling InsightToolkit-3.20.1 on my Linux suse 11.3(64 bit) box, i tried running example provided along with ITK.<br>Some example run fine, but <b>MultiResImageRegistration* examples are giving slightly different output then given in source file.</b><br>
MultiResImageRegistration2 should converge as per the below detail from MultiResImageRegistration2.cxx.<br>The registration converges after $5$ iterations in the first<br> // level, $7$ in the second level and $4$ in the third level. The final<br>
// results when printed as an array of parameters are<br> //<br> // \begin{verbatim}<br> // [1.00164, 0.00147688, 0.00168372, 1.0027, 12.6296, 16.4768]<br>-------------------------------<br>but my executable takes lot of iterations for converging. I want to emphasize here, that no change has been made to the source file.<br>
Run was made like below:<br><br>./MultiResImageRegistration2 ../../InsightToolkit-3.20.1/Examples/Data/BrainT1SliceBorder20.png ../../InsightToolkit-3.20.1/Examples/Data/BrainProtonDensitySliceShifted13x17y.png out.png<br>
and its output was<br>-------------------------------------<br>MultiResolution Level : 0<br><br>0 -1.87377 [0.999988, 5.26965e-05, 2.92263e-05, 1.00007, 2.82271, 29.23] 0<br>1 -1.13243 [1, 3.55154e-05, 2.09008e-05, 1.00008, 15.45, 27.1347] 1<br>
2 -1.38838 [1.00004, 8.32104e-05, 5.34165e-05, 1.00011, 5.32325, 28.6531] 2<br>3 -1.19929 [1.00006, 4.77606e-07, -1.93134e-05, 1.00008, 2.79924, 18.7291] 3<br>4 -1.23267 [1.00004, 1.87947e-05, -8.89719e-06, 1.00009, 10.8252, 17.0881] 4<br>
5 -1.7143 [1, 3.64921e-05, 8.89255e-06, 1.00009, 18.9275, 18.2971] 5<br>6 -1.44958 [1.00002, 2.56425e-05, -1.65816e-06, 1.0001, 12.9226, 20.922] 6<br>7 -1.63302 [1.00003, 1.55103e-05, -8.84177e-06, 1.00011, 13.8223, 15.7569] 7<br>
8 -1.78001 [1.00004, 2.05547e-05, -9.7243e-06, 1.00011, 13.7179, 19.9499] 8<br>9 -1.67048 [1.00003, 3.21431e-05, -4.5119e-06, 1.0001, 12.1907, 16.9622] 9<br>10 -1.8265 [1.00005, 3.86097e-05, -9.16404e-07, 1.00011, 14.6889, 15.9801] 10<br>
11 -1.74105 [1.00006, 3.81516e-05, 1.12975e-06, 1.00011, 13.1032, 17.4283] 11<br>12 -1.86948 [1.00006, 3.79044e-05, 2.25677e-06, 1.00012, 14.7698, 17.0109] 12<br>13 -1.76855 [1.00007, 3.59673e-05, 1.24242e-06, 1.00012, 13.4169, 16.7686] 13<br>
14 -1.85574 [1.00008, 3.95096e-05, 3.39406e-06, 1.00013, 12.1107, 17.196] 14<br>15 -1.82394 [1.00008, 4.14684e-05, 3.53581e-06, 1.00013, 13.1784, 16.9337] 15<br>16 -1.87515 [1.00008, 4.48528e-05, 5.76028e-06, 1.00013, 12.4321, 17.3992] 16<br>
17 -1.84227 [1.00009, 4.56554e-05, 5.19095e-06, 1.00014, 13.1355, 17.4183] 17<br>18 -1.87113 [1.0001, 4.4566e-05, 4.72429e-06, 1.00015, 13.7229, 17.0309] 18<br>19 -1.84301 [1.0001, 4.53401e-05, 4.7149e-06, 1.00015, 13.2549, 17.3438] 19<br>
20 -1.87119 [1.0001, 4.90078e-05, 6.5465e-06, 1.00015, 12.7891, 17.0278] 20<br>21 -1.86387 [1.0001, 4.93968e-05, 6.5028e-06, 1.00015, 13.2101, 17.1875] 21<br>22 -1.87904 [1.00011, 5.11913e-05, 6.90862e-06, 1.00016, 13.1586, 17.6349] 22<br>
23 -1.85838 [1.00011, 4.99116e-05, 6.32473e-06, 1.00016, 13.2756, 17.2941] 23<br>24 -1.87234 [1.00011, 5.06405e-05, 6.38674e-06, 1.00016, 13.142, 16.9595] 24<br>25 -1.87851 [1.00011, 5.60623e-05, 9.50702e-06, 1.00016, 12.9261, 17.1505] 25<br>
26 -1.87278 [1.00011, 5.7016e-05, 9.81952e-06, 1.00017, 13.1566, 17.1573] 26<br>27 -1.87788 [1.00011, 5.79397e-05, 1.03623e-05, 1.00016, 13.1869, 17.3859] 27<br>28 -1.87119 [1.00012, 5.78678e-05, 1.02708e-05, 1.00017, 13.1865, 17.2014] 28<br>
29 -1.87867 [1.00012, 5.93291e-05, 1.09259e-05, 1.00017, 13.2404, 17.3388] 29<br>30 -1.87139 [1.00012, 6.02041e-05, 1.1396e-05, 1.00017, 13.1466, 17.2671] 30<br>31 -1.87646 [1.00012, 6.09047e-05, 1.16142e-05, 1.00017, 13.228, 17.2193] 31<br>
32 -1.87726 [1.00012, 6.10943e-05, 1.15513e-05, 1.00017, 13.185, 17.1572] 32<br>33 -1.87794 [1.00012, 6.12425e-05, 1.16305e-05, 1.00017, 13.1883, 17.2175] 33<br>34 -1.87838 [1.00012, 6.23812e-05, 1.21072e-05, 1.00017, 13.2234, 17.1842] 34<br>
35 -1.87868 [1.00012, 6.25183e-05, 1.21145e-05, 1.00017, 13.2095, 17.2203] 35<br>36 -1.87824 [1.00012, 6.2734e-05, 1.21642e-05, 1.00017, 13.1988, 17.1913] 36<br>37 -1.87921 [1.00012, 6.28541e-05, 1.22088e-05, 1.00017, 13.2007, 17.216] 37<br>
38 -1.8782 [1.00012, 6.32819e-05, 1.23541e-05, 1.00017, 13.1978, 17.1964] 38<br>39 -1.87855 [1.00012, 6.33837e-05, 1.23923e-05, 1.00017, 13.1993, 17.2121] 39<br>40 -1.87925 [1.00013, 6.58186e-05, 1.32416e-05, 1.00018, 13.2, 17.1995] 40<br>
41 -1.87823 [1.00013, 6.5898e-05, 1.32687e-05, 1.00018, 13.2005, 17.2096] 41<br>42 -1.87794 [1.00013, 6.64167e-05, 1.34403e-05, 1.00018, 13.1994, 17.2197] 42<br>-------------------------------------<br>MultiResolution Level : 1<br>
<br>0 -1.62165 [1.00015, 6.03801e-05, 1.17789e-05, 1.00019, 9.95152, 14.8849] 43<br>1 -1.1875 [1.00016, 6.18228e-05, 1.49073e-05, 1.0002, 12.9899, 15.8891] 44<br>2 -1.51398 [1.00017, 6.69607e-05, 1.93186e-05, 1.0002, 12.9537, 19.0889] 45<br>
3 -1.42245 [1.00018, 7.01343e-05, 2.17115e-05, 1.00021, 12.7735, 16.5353] 46<br>4 -1.57939 [1.00018, 7.17956e-05, 2.31559e-05, 1.00021, 13.3021, 18.5139] 47<br>5 -1.47109 [1.00019, 7.0268e-05, 2.19e-05, 1.00021, 12.7688, 16.9647] 48<br>
6 -1.61299 [1.00019, 7.05664e-05, 2.1608e-05, 1.00021, 13.97, 17.4892] 49<br>7 -1.4959 [1.00019, 7.03122e-05, 2.16426e-05, 1.00021, 12.9971, 17.0981] 50<br>8 -1.63338 [1.0002, 6.86924e-05, 2.1011e-05, 1.00022, 13.3451, 16.109] 51<br>
9 -1.5237 [1.0002, 6.81505e-05, 2.07289e-05, 1.00022, 13.1068, 16.9133] 52<br>10 -1.62846 [1.0002, 6.82681e-05, 2.02992e-05, 1.00022, 12.4269, 17.4046] 53<br>11 -1.55341 [1.0002, 6.76953e-05, 1.98522e-05, 1.00022, 13.0085, 17.0697] 54<br>
12 -1.63467 [1.00021, 6.639e-05, 1.92588e-05, 1.00023, 12.8479, 16.4181] 55<br>13 -1.57099 [1.00021, 6.704e-05, 1.98256e-05, 1.00023, 12.9785, 16.9389] 56<br>14 -1.6313 [1.00021, 6.89057e-05, 2.10809e-05, 1.00023, 13.1016, 17.4615] 57<br>
15 -1.60176 [1.00021, 6.8814e-05, 2.06596e-05, 1.00023, 12.8971, 17.0838] 58<br>16 -1.62815 [1.00021, 6.93416e-05, 2.10816e-05, 1.00023, 13.2334, 17.013] 59<br>17 -1.62391 [1.00021, 6.90842e-05, 2.10131e-05, 1.00024, 12.9709, 16.9313] 60<br>
18 -1.63013 [1.00022, 6.98766e-05, 2.14936e-05, 1.00024, 13.0301, 17.1431] 61<br>19 -1.63213 [1.00022, 6.96417e-05, 2.14305e-05, 1.00024, 13.0242, 16.9672] 62<br>20 -1.63369 [1.00022, 6.97123e-05, 2.14339e-05, 1.00024, 12.9752, 17.0992] 63<br>
21 -1.63229 [1.00022, 6.98076e-05, 2.1516e-05, 1.00024, 13.0534, 17.0181] 64<br>22 -1.63476 [1.00022, 6.9642e-05, 2.1329e-05, 1.00024, 12.9642, 17.0051] 65<br>23 -1.63365 [1.00022, 6.99387e-05, 2.15251e-05, 1.00024, 13.0228, 16.9632] 66<br>
24 -1.63359 [1.00022, 6.9969e-05, 2.15261e-05, 1.00024, 13.004, 17.0176] 67<br>25 -1.63559 [1.00022, 6.98748e-05, 2.14739e-05, 1.00024, 12.9975, 16.972] 68<br>26 -1.63425 [1.00022, 6.99632e-05, 2.15374e-05, 1.00024, 13.0102, 17.0066] 69<br>
27 -1.63572 [1.00022, 6.99392e-05, 2.15124e-05, 1.00024, 12.9926, 16.983] 70<br>28 -1.63557 [1.00022, 6.99708e-05, 2.16214e-05, 1.00024, 13.0006, 16.9546] 71<br>29 -1.6335 [1.00022, 7.00353e-05, 2.16619e-05, 1.00024, 12.9988, 16.9781] 72<br>
30 -1.6355 [1.00022, 7.0194e-05, 2.17912e-05, 1.00024, 13.0155, 16.9948] 73<br>31 -1.63563 [1.00022, 7.01802e-05, 2.17694e-05, 1.00024, 13.0007, 16.9831] 74<br>32 -1.63564 [1.00022, 7.01415e-05, 2.17686e-05, 1.00024, 12.9848, 16.9728] 75<br>
33 -1.6343 [1.00022, 7.02017e-05, 2.18139e-05, 1.00024, 12.9946, 16.9844] 76<br>34 -1.63558 [1.00022, 7.01902e-05, 2.18266e-05, 1.00024, 12.9949, 16.9723] 77<br>35 -1.6344 [1.00022, 7.02139e-05, 2.18457e-05, 1.00024, 12.9998, 16.9807] 78<br>
36 -1.63558 [1.00022, 7.02012e-05, 2.18512e-05, 1.00024, 12.9932, 16.9766] 79<br>37 -1.63544 [1.00022, 7.02338e-05, 2.18765e-05, 1.00024, 12.9986, 16.9796] 80<br>38 -1.63556 [1.00022, 7.02559e-05, 2.1918e-05, 1.00024, 12.9996, 16.9748] 81<br>
39 -1.63515 [1.00022, 7.02707e-05, 2.19276e-05, 1.00024, 13, 16.9787] 82<br>40 -1.63555 [1.00022, 7.02872e-05, 2.19443e-05, 1.00024, 12.9967, 16.981] 83<br>41 -1.63561 [1.00022, 7.02763e-05, 2.19467e-05, 1.00024, 12.9962, 16.9779] 84<br>
42 -1.63553 [1.00022, 7.0289e-05, 2.19585e-05, 1.00024, 12.9988, 16.9782] 85<br>43 -1.63555 [1.00023, 7.03123e-05, 2.19736e-05, 1.00024, 13.001, 16.9793] 86<br>44 -1.63556 [1.00023, 7.03133e-05, 2.19762e-05, 1.00024, 12.999, 16.9793] 87<br>
45 -1.63558 [1.00023, 7.03392e-05, 2.2003e-05, 1.00024, 12.997, 16.9797] 88<br>46 -1.63557 [1.00023, 7.0332e-05, 2.20053e-05, 1.00024, 12.997, 16.9781] 89<br>47 -1.63555 [1.00023, 7.03397e-05, 2.20109e-05, 1.00024, 12.9983, 16.9781] 90<br>
48 -1.6355 [1.00023, 7.03503e-05, 2.20177e-05, 1.00024, 12.9995, 16.9785] 91<br>49 -1.63558 [1.00023, 7.03612e-05, 2.20263e-05, 1.00025, 12.9992, 16.9798] 92<br>50 -1.63564 [1.00023, 7.03605e-05, 2.2028e-05, 1.00025, 12.9983, 16.9792] 93<br>
-------------------------------------<br>MultiResolution Level : 2<br><br>0 -1.28555 [1.00023, 7.17596e-05, 2.34728e-05, 1.00025, 12.3864, 17.7702] 94<br>1 -1.20689 [1.00023, 7.17569e-05, 2.33515e-05, 1.00025, 13.0162, 17.2769] 95<br>
2 -1.2882 [1.00023, 7.20532e-05, 2.33524e-05, 1.00026, 12.8846, 16.4878] 96<br>3 -1.2738 [1.00023, 7.32712e-05, 2.40743e-05, 1.00026, 13.2028, 17.0431] 97<br>4 -1.29413 [1.00023, 7.2987e-05, 2.41593e-05, 1.00026, 12.7043, 16.9264] 98<br>
5 -1.29154 [1.00023, 7.28283e-05, 2.39671e-05, 1.00026, 13.0967, 17.0438] 99<br>6 -1.29226 [1.00023, 7.32004e-05, 2.42714e-05, 1.00026, 12.8308, 16.8523] 100<br>7 -1.30052 [1.00023, 7.35853e-05, 2.44347e-05, 1.00026, 13.0505, 16.9953] 101<br>
8 -1.28733 [1.00023, 7.39501e-05, 2.50317e-05, 1.00026, 12.8635, 17.0903] 102<br>9 -1.29795 [1.00023, 7.41911e-05, 2.51215e-05, 1.00026, 12.9954, 16.9866] 103<br>10 -1.28539 [1.00023, 7.44061e-05, 2.54409e-05, 1.00026, 12.88, 17.0551] 104<br>
11 -1.29558 [1.00023, 7.46609e-05, 2.55977e-05, 1.00026, 12.9805, 17.0172] 105<br>12 -1.28655 [1.00023, 7.59312e-05, 2.66034e-05, 1.00026, 13.0043, 16.9125] 106<br>13 -1.29005 [1.00023, 7.58524e-05, 2.66422e-05, 1.00026, 12.9799, 16.9949] 107<br>
14 -1.28649 [1.00023, 7.65503e-05, 2.72752e-05, 1.00026, 12.9877, 17.0805] 108<br>15 -1.2893 [1.00023, 7.67555e-05, 2.74021e-05, 1.00026, 13.0005, 17.013] 109<br>16 -1.28504 [1.00023, 7.71766e-05, 2.77733e-05, 1.00026, 12.9456, 17.0158] 110<br>
17 -1.28871 [1.00023, 7.72349e-05, 2.78222e-05, 1.00026, 12.9872, 17.0017] 111<br>18 -1.28581 [1.00023, 7.74398e-05, 2.80487e-05, 1.00026, 12.9526, 17.008] 112<br>19 -1.28831 [1.00023, 7.75173e-05, 2.81092e-05, 1.00026, 12.9804, 17.0038] 113<br>
20 -1.28645 [1.00023, 7.8997e-05, 2.94688e-05, 1.00026, 12.972, 17.0246] 114<br>21 -1.2875 [1.00023, 7.91652e-05, 2.9606e-05, 1.00027, 12.9829, 17.0103] 115<br>22 -1.28633 [1.00023, 7.94498e-05, 2.98614e-05, 1.00027, 12.9738, 16.9947] 116<br>
23 -1.28705 [1.00023, 7.95571e-05, 2.99512e-05, 1.00027, 12.9833, 17.0056] 117<br>24 -1.28626 [1.00023, 7.97569e-05, 3.01446e-05, 1.00027, 12.972, 17.0035] 118<br>25 -1.28721 [1.00023, 7.9854e-05, 3.0225e-05, 1.00027, 12.981, 17.0054] 119<br>
26 -1.28646 [1.00023, 8.03125e-05, 3.06464e-05, 1.00027, 12.9739, 17.0035] 120<br>27 -1.28705 [1.00023, 8.03901e-05, 3.07116e-05, 1.00027, 12.9796, 17.0051] 121<br>28 -1.28658 [1.00022, 8.14113e-05, 3.1626e-05, 1.00027, 12.9851, 17.0072] 122<br>
29 -1.28612 [1.00022, 8.14614e-05, 3.16754e-05, 1.00027, 12.9806, 17.0057] 123<br>30 -1.28651 [1.00022, 8.18571e-05, 3.20354e-05, 1.00027, 12.9765, 17.0034] 124<br>31 -1.28683 [1.00022, 8.19314e-05, 3.20996e-05, 1.00027, 12.9799, 17.005] 125<br>
32 -1.28657 [1.00022, 8.33454e-05, 3.33747e-05, 1.00027, 12.9794, 17.0088] 126<br>33 -1.28666 [1.00022, 8.34364e-05, 3.34534e-05, 1.00027, 12.9801, 17.0059] 127<br>34 -1.28657 [1.00022, 8.38365e-05, 3.38138e-05, 1.00027, 12.9782, 17.0035] 128<br>
35 -1.28671 [1.00022, 8.39123e-05, 3.3881e-05, 1.00027, 12.98, 17.0052] 129<br>36 -1.28659 [1.00022, 8.44641e-05, 3.43794e-05, 1.00027, 12.9783, 17.0062] 130<br>37 -1.28675 [1.00022, 8.45361e-05, 3.4442e-05, 1.00027, 12.9798, 17.0058] 131<br>
38 -1.28663 [1.00022, 8.49391e-05, 3.48032e-05, 1.00027, 12.9796, 17.0042] 132<br>39 -1.28664 [1.00022, 8.5028e-05, 3.48835e-05, 1.00027, 12.9797, 17.0055] 133<br>40 -1.28663 [1.00022, 8.778e-05, 3.73549e-05, 1.00027, 12.9789, 17.005] 134<br>
41 -1.28671 [1.00022, 8.784e-05, 3.74083e-05, 1.00027, 12.9795, 17.0054] 135<br>42 -1.28666 [1.00022, 8.82254e-05, 3.77538e-05, 1.00027, 12.9798, 17.0062] 136<br>43 -1.28667 [1.00022, 8.8309e-05, 3.78288e-05, 1.00027, 12.9795, 17.0056] 137<br>
44 -1.28667 [1.00022, 8.87527e-05, 3.82256e-05, 1.00027, 12.98, 17.0056] 138<br>45 -1.28664 [1.00022, 8.88064e-05, 3.82742e-05, 1.00027, 12.9796, 17.0056] 139<br>46 -1.28666 [1.00022, 8.91826e-05, 3.86117e-05, 1.00027, 12.9792, 17.0058] 140<br>
47 -1.28671 [1.00022, 8.92549e-05, 3.86761e-05, 1.00027, 12.9795, 17.0057] 141<br>48 -1.28669 [1.00022, 8.95278e-05, 3.89205e-05, 1.00027, 12.9793, 17.0056] 142<br>49 -1.2867 [1.00022, 8.96052e-05, 3.89897e-05, 1.00027, 12.9795, 17.0057] 143<br>
50 -1.28669 [1.00022, 8.9917e-05, 3.9269e-05, 1.00027, 12.9793, 17.0057] 144<br>51 -1.28671 [1.00022, 8.99883e-05, 3.93327e-05, 1.00027, 12.9795, 17.0057] 145<br>52 -1.2867 [1.00022, 9.02924e-05, 3.96051e-05, 1.00027, 12.9794, 17.0057] 146<br>
Optimizer stop condition: RegularStepGradientDescentOptimizer: Step too small after 53 iterations. Current step (8.50706e-05) is less than minimum step (0.0001).<br>Optimizer Stopping Condition = 2<br>Result = <br> Translation X = 12.9794<br>
Translation Y = 17.0057<br> Iterations = 54<br> Metric value = -1.2867<br><br><br>Any idea, why my run is taking too many iteration to complete ???<br>Cheers<br>Nain<br>