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fScan Reference Manual, Chapter 2 (CmdLineOptions:Expr): censor
usage: -expr censor [timeref] [flag [filloption]]
CENSOR replaces flagged with new values, or it can completely remove images. Which images to censor is controlled by a reference time series. By default, the reference time series is the data set's “ACTIVE” reference timeline (0/1 value for each image). Alternatively, a reference time series can be specified explicitly by name as the first argument (TIMEREF).
Usually the reference series should have at least as many values as their are images, in which case the images to be censored are those for which the corresponding reference value is less than or equal to zero (any positive reference value means keep that image).
Alternatively, if the FLAG argument includes the 16 option, then the reference series is assumed to be an explicit list of which image numbers to censor. Image numbering always starts with 0 for the first image of the first volume, then the 2nd image of the first volume, etc. For example, if a data set has 20 image slices per volume and TIMEREF has values [ 0, 4, 107 ] then the only images to be censored would be: slice 0 volume 0, slice 4 volume 0, and slice 7 volume 4. Such a TIMEREF must contain only unique values sorted in ascending order; the list can be any length up to the total number of images.
What happens to censored images depends on the values of the FLAG and FILLOPTION arguments.
FILLOPTION can be a number, indicating wwhich image volume to use as fill images, or it can be the name of a 3D image data set (with the same XYZ dimensions as the data being censored).
FLAG - censoring operation:
/* val: 0 - replace with linear interpolation (unless FILLOPTION specified) 1 - replace with spline interpolation 2 - replace with 0's 3 - excise 4 - match post-mean to pre-mean 8 - reference list is index of image to remove; otherwise is 0/1 flag 16 - replace with value at 1st censored timept at or after timept VAL2 17 - replace with value at 1st uncensored timept at or after VAL2 18 - replace with value at timept VAL2 32 - replace with FILLOPTION data set images Default FLAG is: 0 if FILLOPTION is 0 or not specified, or 32 if FILLOPTION is data set name, or 16 if FILLOPTION is a number
Other FLAG values can be combined with the above byb addition:
/* val: 0 - (default) replace with linear interpolation; or same as VAL=8 if VAL2 is non-zero 1 - replace with spline interpolation 2 - replace with 0's 3 - excise 4 - match post-mean to pre-mean 8 - replace with value at 1st censored timept at or after timept VAL2 9 - replace with value at 1st uncensored timept at or after VAL2 10 - replace with value at timept VAL2 16 - active is t-index; otherwise is 0/1 flag
See Also:
fScan Home,
fScan Manual,
CmdLineOptions,
Expression Command,
Manual Help