extracttag

extract tag points from a probability mask volume

extracttag [options] <prob_mask_filename>

DESCRIPTION

extracttag extracts tag points from a probability mask volume. Tag points are spatial coordinates sampled from voxels that meet specified threshold criteria within the mask. The output can be either a tag file or a tag volume. This tool is used in the N3 non-uniformity correction pipeline to select representative sample points for field estimation.

OPTIONS

-verbose
Print progress information.
-clobber
Overwrite an existing output file.
-debug <n>
Set debug level to n.
-volume
Generate a tag volume as output.
-tag
Generate a tag file as output.
-mintags
Set the minimum number of tags to extract.
-maxtags
Set the maximum number of tags to extract. Use 0 to extract all qualifying tags.
-threshold <min> <max>
Set the lower and upper intensity thresholds for tag extraction.
-top_thres <val>
Set the upper threshold value (default: 1.001).
-label
Use voxel label values.
-mask <mask.mnc>
Specify a mask volume to restrict tag extraction.
-user_mask_value <n>
Set the mask value for inclusion (default: 1).
-mask_floor <n>
Set the minimum mask value for inclusion (default: 1).
-mask_ceil <n>
Set the maximum mask value for inclusion.
-mask_binvalue <n>
Set the binary mask value for inclusion.
-world
Traverse the mask volume in world coordinates.
-random
Use random step sizes when traversing the volume.
-comment
Add a comment to the output tag file.
-append
Append to an existing tag file instead of overwriting.

EXAMPLES

extracttag -tag -maxtags 10000 prob_mask.mnc > tags.tag

extracttag -mask brain_mask.mnc -threshold 0.5 1.0 prob_mask.mnc > tags.tag

AUTHOR

John G. Sled - McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University.

COPYRIGHTS

Copyright &copy; 1998 by John G. Sled

SEE ALSO

nu_estimate, nu_correct, volume_stats