[MINC-development] accuracy in mritotal. better tool?

Yasunari Tosa minc-development@bic.mni.mcgill.ca
05 Aug 2003 17:20:29 -0400


--=-MTMNSz2vzKXae07QG71B
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

Hi, MINC people:

I'm not getting the accuracy in mritotal results.  
I would appreciate it very much for your help in resolving the accuracy.

mritotal -verbose -debug -clobber -protocol icbm orig.mnc talairach.xfm

My test was to modify the world translation by a fixed amount and see
how the result changes
(therefore the image never changes).

What I was surprized was the following:

Even though the rotation and the scaling parts are quite stable, the
translation part error
is quite large (up to 1.48 mm).   

The original volume is 256^3 with 1 mm voxel.

The last two column is the difference and the error from the original in
translation
The fourth column is the translation part.

Original : world_translation is (0,0,0):
=============================
	1.10129165649414	0.0375710912048817	-0.0232741367071867	0.884597778320312				
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.91514205932617				
	0.0234725382179022	0.0233993344008923	1.14845287799835	8.22117519378662				

world_translation is (10, 0, 0)
=======================							                                                   diff                   error
	1.10129165649414	0.0375710912048817	-0.0232741367071867	-10.1283187866211		11.0129165649414	10	1.01291656494141
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.55157375335693		-0.36356830596924	0	-0.36356830596924
	0.0234725382179022	0.0233993344008923	1.14845287799835	7.98645114898682		0.234724044799799	0	0.234724044799799
								
world_translation is (0,10,0)
======================				                                                   diff                     error               
	1.10129177570343	0.0375712215900421	-0.0232741497457027	0.508886873722076		0.375710904598236	0	0.375710904598236
	-0.0363569855690002	1.05287170410156	-0.0207088124006987	-17.4438610076904		10.5287189483642	10	0.528718948364231
	0.0234725456684828	0.0233993232250214	1.14845287799835	7.98718357086182		0.233991622924799	0	0.233991622924799

world_translation is (0, 0, 10)
=======================								                                                  diff                   error
	1.10129165649414	0.0375710912048817	-0.0232741367071867	1.11733937263489		-0.232741594314578	0	-0.232741594314578
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.70805358886719		-0.20708847045898	0	-0.20708847045898
	0.0234725382179022	0.0233993344008923	1.14845287799835	-3.26335191726685		11.4845271110535	10	1.48452711105347

-- 
Yasunari Tosa, Ph.D.
R&D Enginner				email: tosa@nmr.mgh.harvard.edu
Mass. General Hospital NMR Center	phone:  		
Building 149-2301
13th Street			        fax  :
Charlestown, MA 02129


--=-MTMNSz2vzKXae07QG71B
Content-Type: text/html; charset=utf-8
Content-Transfer-Encoding: 7bit

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 TRANSITIONAL//EN">
<HTML>
<HEAD>
  <META HTTP-EQUIV="Content-Type" CONTENT="text/html; CHARSET=UTF-8">
  <META NAME="GENERATOR" CONTENT="GtkHTML/3.0.7">
</HEAD>
<BODY>
Hi, MINC people:<BR>
<BR>
I'm not getting the accuracy in mritotal results.&nbsp; <BR>
I would appreciate it very much for your help in resolving the accuracy.<BR>
<BR>
mritotal -verbose -debug -clobber -protocol icbm orig.mnc talairach.xfm<BR>
<BR>
My test was to modify the world translation by a fixed amount and see how the result changes<BR>
(therefore the image never changes).<BR>
<BR>
What I was surprized was the following:<BR>
<BR>
Even though the rotation and the scaling parts are quite stable, the translation part error<BR>
is quite large (up to 1.48 mm).&nbsp;&nbsp; <BR>
<BR>
The original volume is 256^3 with 1 mm voxel.<BR>
<BR>
The last two column is the difference and the error from the original in translation<BR>
The fourth column is the translation part.<BR>
<BR>
Original : world_translation is (0,0,0):<BR>
=============================<BR>
	1.10129165649414	0.0375710912048817	-0.0232741367071867	0.884597778320312				<BR>
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.91514205932617				<BR>
	0.0234725382179022	0.0233993344008923	1.14845287799835	8.22117519378662				<BR>
<BR>
world_translation is (10, 0, 0)<BR>
=======================							&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; diff&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; error<BR>
	1.10129165649414	0.0375710912048817	-0.0232741367071867	-10.1283187866211		11.0129165649414	10	1.01291656494141<BR>
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.55157375335693		-0.36356830596924	0	-0.36356830596924<BR>
	0.0234725382179022	0.0233993344008923	1.14845287799835	7.98645114898682		0.234724044799799	0	0.234724044799799<BR>
								<BR>
world_translation is (0,10,0)<BR>
======================				&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; diff&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; error&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <BR>
	1.10129177570343	0.0375712215900421	-0.0232741497457027	0.508886873722076		0.375710904598236	0	0.375710904598236<BR>
	-0.0363569855690002	1.05287170410156	-0.0207088124006987	-17.4438610076904		10.5287189483642	10	0.528718948364231<BR>
	0.0234725456684828	0.0233993232250214	1.14845287799835	7.98718357086182		0.233991622924799	0	0.233991622924799<BR>
<BR>
world_translation is (0, 0, 10)<BR>
=======================								&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; diff&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; error<BR>
	1.10129165649414	0.0375710912048817	-0.0232741367071867	1.11733937263489		-0.232741594314578	0	-0.232741594314578<BR>
	-0.0363568961620331	1.05287253856659	-0.020708842203021	-6.70805358886719		-0.20708847045898	0	-0.20708847045898<BR>
	0.0234725382179022	0.0233993344008923	1.14845287799835	-3.26335191726685		11.4845271110535	10	1.48452711105347<BR>
<BR>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%">
<TR>
<TD>
<PRE>-- 
Yasunari Tosa, Ph.D.
R&amp;D Enginner				email: tosa@nmr.mgh.harvard.edu
Mass. General Hospital NMR Center	phone:  		
Building 149-2301
13th Street			        fax  :
Charlestown, MA 02129
</PRE>
</TD>
</TR>
</TABLE>

</BODY>
</HTML>

--=-MTMNSz2vzKXae07QG71B--