Dear all

Apologize for the rather long email. Please found bellow description of
a bug that I found on my data using Max filter 2.1.

I first run autobad and it works fine:
/neuro/bin/util/maxfilter-2.1 -f /SubjectDirectory/pd_1_raw.fif -o
pd_1_raw_sss.fif -v | tee pd_1_raw_autobad.log

Then I try just SSSt and movement detection (every 1000ms; NB no
movement correction):

/neuro/bin/util/maxfilter-2.1 -f /SubjectDirectory/pd_1_raw.fif -o
pd_1_raw_ssst.fif -ctc /neuro/databases/ctc/ct_sparse.fif -cal
/neuro/databases/sss/sss_cal.dat -frame head -origin 0 0 40 -format
float -autobad off -bad 1031 1111 -st 4 -headpos -hpistep 1000 -hp
pd_1_raw_mvpos.txt -ds 4 -v | tee pd_1_raw_ssst.log

Though I have 3 coils accepted out of 5, the program seems again to
work, a *.fif is output (though I note that I had to remove the option
"-hpisubt amp", which doesn't seem to be present in maxfilter 2.1?)

HOWEVER, when I try the critical movement compensation (every 200ms):

/neuro/bin/util/maxfilter-2.1 -f /SubjectDirectory/pd_1_raw.fif -o
pd_1_raw_mvcomp.fif -ctc /neuro/databases/ctc/ct_sparse.fif -cal
/neuro/databases/sss/sss_cal.dat -frame head -origin 0 0 40 -format
float -autobad off -bad 1031 1111 -st 4 -movecomp -hpistep 200 -ds 4 -v
| tee pd_1_raw_movecomp.log

I got a major crash:

[...]
--- Reading raw tag #b = 569/569 (#t = 666.000) ---
Static bad channels (2): 1031 1111
HPI amplitude correlation 642.000: 0.999 (275 chnls > 0.95)
HPI amplitude correlation 643.000: 0.999 (278 chnls > 0.95)
HPI amplitude correlation 644.000: 0.999 (257 chnls > 0.95)
HPI amplitude correlation 645.000: 0.999 (285 chnls > 0.95)
HPI amplitude correlation 646.000: 0.998 (284 chnls > 0.95)
HPI amplitude correlation 647.000: 0.997 (283 chnls > 0.95)
HPI amplitude correlation 648.000: 0.996 (281 chnls > 0.95)
HPI amplitude correlation 649.000: 0.995 (281 chnls > 0.95)
HPI amplitude correlation 650.000: 0.994 (280 chnls > 0.95)
HPI amplitude correlation 651.000: 0.993 (279 chnls > 0.95)
HPI amplitude correlation 652.000: 0.991 (277 chnls > 0.95)
HPI amp*** glibc detected ***
/neuro/bin/util/x86_64-pc-linux-gnu/maxfilter-2.1: free(): invalid
pointer: 0x000000000c7cfdc0 ***
======= Backtrace: =========
/lib64/libc.so.6[0x37c8e722ef]
/lib64/libc.so.6(cfree+0x4b)[0x37c8e7273b]
[...]
Continuous HPI was active on 547/569 buffers.
Abort

Please note that I have a similar bug with another file from the same
participant but this time during ssst (with the following warning
message: "Program died due to signal 11, all output files were deleted!").

Note also that I have again another file from the same participant,
where there are only 3 coils accepted out of 5, but for which all
functions (autobad, ssst, movecomp, trans) seem to work perfectly fine.

Last information - When I used the previous version of Max Filter on
those problematic files, the program finds that the fit of the 5 Hpi
coils is bad (all are in parentheses).

Any suggestions would be greatly appreciated.

Many thanks

Pierre

--
Dr Pierre Gagnepain
MRC Cognition & Brain Sciences Unit
15 Chaucer Road
Cambridge
CB2 7EF, UK
Tel: +44 (0) 1223 273701