[Brains-users] New b2 command::b2 get image value

[Greg Harris]

This announcement documents a new ability to numerically
sample a point in image space for consumption by a Tcl script.

When applied to an untransformed image, 'b2 get image value i1 $x $y $z'
will retrieve the stored value for image i1 at <x,y,z>.  If x, y, or z 
are not
integers, a trilinear interpolation is done to obtain the value.

If 'millimeter-flag= true' is given, x, y, and z are scaled through the
resolutions provided for image i1.

In addition, if there is a transform set, the transform is part of the
image address decoding.

= = = APPENDIX = = =
Usage   b2 get image value [imageID] [X] [Y] [Z] <millimeter-flag= 
true|false> <time-index= index>

Description     Command to interpolate an intensity for the image in
             the region defined by the given X, Y, and Z coordinates.

[imageID]       An identifier for an image

[X]     X-Y-Z coordinates to sample an interpolation in the space of the 
image.
[Y]
[Z]
<millimeter-flag= >     Flag signaling if the user is supplying
             a position in millimeters rather than voxels.

<time-index= >  Time index into a 4D dataset. By default the zero
             index time point is used

Return  A list of lists containing the measurement
             results.  The sublists contain the result description
             and measurement value.  If an error occurs, then the
             error status of -1 is returned