Mode 2D: Resize

 

This mode is used to create a new 3D volume composed of parallel axial slices from one or more source group of slices.

 

The source slices do not have to form a 3D group.  They can be in any orientation. You can have missing slices in the source group. Your source dataset can even be a spherical system. 

 

The re-sliced volume will always be in a Cartesian system, with the slices in Axial direction (X-Y plane).  All the slices will be equidistant.  If desired you can have isotropic voxels (the voxel spacing equal in the 3 (X/Y/Z) directions).

 

If you select multiple groups of images as the source, the resulting volume will cover the complete volume of the sources.  If the sources overlap, the resulting voxels in the overlapped regions will be a merge of the sources voxels.  You have a choice of 4 merge techniques:

 

•Max:          The maximum voxel value is used.

•Mean:          The mean value of all the overlapping voxels is used.

•Closest:          We compute the distance between the center of the re-slice voxel and the nearest center of the source voxel for each groups. We keep only the value from the closets voxel.

•Mix:          The ponderated value of the 3 closest voxels.  Sum the voxel values, starting with the closest, each successive voxels having half the weight of the previous ones.

 

The new volume will be in the same study as the first of the source groups, but with a series number starting at 100 (if you compute multiple volumes, the series number will be incremented by 1 each time). 

 

Since the re-sliced frames will cover the entire volume of the source volumes, by specifying a new resolution, the voxel's size are automatically known and vice-versa.

 

If the re-sliced voxels are smaller than the source voxels, they are computed by cubic interpolation from the original voxels at that location.  If the re-sliced voxels are larger than the source voxels, it is sub-sampled at the resolution of the source and the mean value of these sub-samples is used.

 

So, when you click compute, here's what happen:

 

•For each source groups, we compute the position in the target groups of the corners of each of the re-sliced voxels.

•If you have multiple source groups and selected either the "Max" or "Mix" merge method, we compute the distance between the center of each re-sliced voxels and the closest center of source voxels for each source groups.

•We compute the new voxel values (GLI and TAG) for each of the re-sliced voxels.

•A new group of re-sliced data is created.

 

 

From the Graphic Interface

 

 

 

Group selection

The module will analyze the class tree to locate any candidate groups and present you with a list of these.  To be available a "group" must be a class containing frames that create a 3D volume.  The frames must be aligned, parallel and equidistant.

 

When you click on a group, the module will populate the resolution and size fields with the information extracted from the group.  You can also use this as a "reset" of the values in the interface.

 

Resolution / pixel size

You can specify the new size of the created re-slice group either though a new resolution or through new pixel dimensions..

 

 

Isometric

When you enable the "Isometric" option, the interface change a little bit:  Only the resolution/size of the "X" direction can be modified.  The resulting voxel size for the "X" direction will then be used for the "Y" and "Z" direction, insuring that the target voxels are isometric.

 

Input fields

Depending on the "Resolution / Size" buttons, you can specify the target voxel size by either it's new resolution or new dimensions.  The matching resolutions or sizes are also updated and displayed on the same line.

 

Merge mode

If you have more than 1 group of frames selected, some  of these may overlap one another.  In this case, you have a choice of how you want each resulting voxel to combine the voxels computed from the different groups.  The choices are:

 

Max

 

The maximum voxel value is used.

Mean

 

The mean value of all the overlapping voxels is used.

Closest

 

We compute the distance between the center of the re-slice voxel and the nearest center of the source voxel for each groups. We keep only the value from the group with the closets voxel.

 

Mix

 

The ponderated value of the 3 closest voxels.  Sum the voxel values, starting with the closest, each successive voxels having half the weight of the previous ones.

 

Compute

Start the computation that will create the new resized slices.

 

 

From the Display Area

 

There is no Display Area interaction specific to this mode.

 

 

From the Keyboard

 

There is no keyboard interface specific to this mode.

 

 

From the Command Line

 

There is no command line or variables associated with this mode.