From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: br.png Type: image/png Size: 51645 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tl.png Type: image/png Size: 51688 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: tr.png Type: image/png Size: 46804 bytes Desc: not available URL: From andreas.staude at bam.de Tue Nov 5 11:11:34 2013 From: andreas.staude at bam.de (Staude, Andreas) Date: Tue, 5 Nov 2013 16:11:34 +0000 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527914C3.8030706@bam.de> References: <527914C3.8030706@bam.de> Message-ID: <527918B5.9080709@bam.de> Hello RTk-users, I try to use the SART algorithm, but the results are worse than those obtained with FDK (see attached images). The FDK result looks like expected, so I assume that I have the data format and the reconstruction geometry set properly. For SART I used the same parameters and already tried with different values of lambda and niterations. Does anyone have an idea what went wrong? Is there some kind of smoothing or regularisation applied in the SART implementation? Many thanks in advance! Cheers, Andreas -- =============================================================== Dr. Andreas Staude Fachbereich 8.5 "Mikro-ZfP", Computertomographie BAM Bundesanstalt f?r Materialforschung und -pr?fung Unter den Eichen 87 D-12205 Berlin Germany Tel.: ++49 30 8104 4140 Fax: ++49 30 8104 1837 =============================================================== -------------- next part -------------- A non-text attachment was scrubbed... Name: fdk.jpg Type: image/jpeg Size: 119717 bytes Desc: fdk.jpg URL: -------------- next part -------------- A non-text attachment was scrubbed... Name: sart.jpg Type: image/jpeg Size: 25084 bytes Desc: sart.jpg URL: From simon.rit at creatis.insa-lyon.fr Tue Nov 5 13:11:59 2013 From: simon.rit at creatis.insa-lyon.fr (Simon Rit) Date: Tue, 5 Nov 2013 19:11:59 +0100 Subject: [Rtk-users] Result from SART is worse than from FDK In-Reply-To: <527918B5.9080709@bam.de> References: <527914C3.8030706@bam.de> <527918B5.9080709@bam.de> Message-ID: Hi Andreas, Thanks for the report. We know that the implementation of SART is imperfect, we haven't been working a lot on it... It seems that you haven't reached convergence. One potential cause is that we use a heuristic for the sum of the weights (denominator in the SART formula) instead of the exact sum. The weight is constant and equals the diagonal of your volume (see line 165 in rtkSARTConeBeamReconstructionFilter.txx). Maybe this is completely wrong in your case. Could you try to increase lambda to see if that helps? To help us do some tests, I would advise you do reproduce your geometry with simulations of the Shepp Logan phantom (see wiki.openrtk.org). Simon On Tue, Nov 5, 2013 at 5:11 PM, Staude, Andreas wrote: > Hello RTk-users, > > I try to use the SART algorithm, but the results are worse than those > obtained with FDK (see attached images). > > The FDK result looks like expected, so I assume that I have the data > format and the reconstruction geometry set properly. For SART I used the > same parameters and already tried with different values of lambda and > niterations. > > Does anyone have an idea what went wrong? Is there some kind of > smoothing or regularisation applied in the SART implementation? > > Many thanks in advance! > > Cheers, > > Andreas > > > -- > > =============================================================== > Dr. Andreas Staude > Fachbereich 8.5 "Mikro-ZfP", Computertomographie > BAM Bundesanstalt f?r Materialforschung und -pr?fung > Unter den Eichen 87 > D-12205 Berlin > Germany > > Tel.: ++49 30 8104 4140 > Fax: ++49 30 8104 1837 > =============================================================== > > > > > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users > From menjiawan at gmail.com Sat Nov 9 07:52:57 2013 From: menjiawan at gmail.com (WANG Mengjiao) Date: Sat, 09 Nov 2013 20:52:57 +0800 Subject: [Rtk-users] Reconstruction problem of C-arm projections Message-ID: <527E3029.5080003@gmail.com> Hi, all. I am dealing with the fdk reconstruction of projections from a GE Innova 4100IQ C-arm equipment. The rotational scan covered about 200 degree. SID = 720. SDD = 1195. The detector is centered. For the first try, I used the rtkfdk.exe for reconstruction, it popped up some output window. The program was still running, but never gave any reconstructed result. For the second try, I changed the source code of rtkfdk.cxx by disabling the displaced detector filter and short scan filter. This time the program worked and gave me some reconstructed images. But the images are very lousy. Does anybody has clue for this situation? PS: The rotational projections, the geometry file, and the screen shot of the reconstructed images can be downloaded by this link: https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 Thanks in advance. MJ From marc.vila-oliva at creatis.insa-lyon.fr Wed Nov 13 11:55:27 2013 From: marc.vila-oliva at creatis.insa-lyon.fr (Marc Vila Oliva) Date: Wed, 13 Nov 2013 17:55:27 +0100 Subject: [Rtk-users] Reconstruction problem of C-arm projections In-Reply-To: <527E3029.5080003@gmail.com> References: <527E3029.5080003@gmail.com> Message-ID: <1384361728.18741.11.camel@mvila-laptop> Hello Mr. Wang, I have tried to reconstruct your data-set using your geometry file and your projections provided in your DropBox. Considering the number of projections (292) and the limited angle view (193.1 degrees), I would say that the results (see attached pictures) are not that bad. Note that your reconstructed data-set will present truncation due to the truncated projections that are being used. Therefore you should add a padded value in order to correct this effect. One question, how do you pass from your raw images to attenuation images? In my case I just took the -log of the projections divided by the max_value (aprox.). I also cropped a bit the projections due to a high-value frame around the projections. Then I ran the following command: // fdk reconstruction rtkfdk -p . -r Cropped_minuslogprojections.mhd -g geometry.xml -o test_hann.mha --dimension 128 --spacing 2 --pad 1.2 // mask fov rtkfieldofview -p projections/. -r im1_.*.mhd -g geometry.xml -o test_fov.mha --reconstruction test_hann.mha I hope it helps! Cheers, Marc VILA On Sat, 2013-11-09 at 20:52 +0800, WANG Mengjiao wrote: > Hi, all. > I am dealing with the fdk reconstruction of projections from a GE Innova > 4100IQ C-arm equipment. The rotational scan covered about 200 degree. > SID = 720. SDD = 1195. > The detector is centered. > For the first try, I used the rtkfdk.exe for reconstruction, it popped > up some output window. The program was still running, but never gave any > reconstructed result. > For the second try, I changed the source code of rtkfdk.cxx by disabling > the displaced detector filter and short scan filter. This time the > program worked and gave me some > reconstructed images. But the images are very lousy. > Does anybody has clue for this situation? > PS: The rotational projections, the geometry file, and the screen shot > of the reconstructed images can be downloaded by this link: > https://www.dropbox.com/sh/y5iyfjtcc9i49n0/AXso1Lvbg3 > Thanks in advance. > MJ > _______________________________________________ > Rtk-users mailing list > Rtk-users at openrtk.org > http://public.kitware.com/cgi-bin/mailman/listinfo/rtk-users -------------- next part -------------- A non-text attachment was scrubbed... Name: bl.png Type: image/png Size: 49923 bytes Desc: not available URL: -------------- next part -------------- A non-text attachment was scrubbed... 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