Maverick/View Virtual Family Together: Difference between revisions
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Now Merlin can be used to create a scene containing these labelmaps and indexed via those .csv files. Use the standard labelmap import process of Merlin to achieve this. | Now Merlin can be used to create a scene containing these labelmaps and indexed via those .csv files. Use the standard labelmap import process of Merlin to achieve this. | ||
= Create a new version of the woman that is shaped like the man = | = Create a new version of the woman that is shaped somewhat like the man = | ||
To simulate different size people, the virtual woman (Ella) can be registered with the virtual man (Duke) using a deformable (BSpline) transform. In this manner, the woman will take on aspects of the shape of the man. The RegisterImages module accomplishes this | To simulate different size people, the virtual woman (Ella) can be registered with the virtual man (Duke) using a deformable (BSpline) transform. In this manner, the woman will take on aspects of the shape of the man. The RegisterImages module accomplishes this |
Revision as of 09:01, 7 October 2008
Create a scene using the virtual family
First convert two members of the virtual family
VirtualFamilyTxtToMhdCsv Duke_34y_v5_2mm.txt Duke_34y_v5_2mm.raw Duke.mhd Duke.csv VirtualFamilyTxtToMhdCsv Ella_26y_v2_2mm.txt Ella_26y_v2_2mm.raw Ella.mhd Ella.csv
This produces representations in the .mhd format.
One wacky thing, the man is imaged head-first while the woman is imaged feet-first. This can be made consistent by adding orientation information to the woman's header file.
vi Ella.mhd
Add the line before the last line of the file.
Orientation = 1 0 0 0 1 0 0 0 -1
The final -1 causes the z-axis to be flipped. The new Ella.mhd should look like this:
NDims = 3 DimSize = 265 150 840 HeaderSize = -1 ElementType = MET_UCHAR ElementByteOrderMSB = True ElementSpacing = 2 2 2 Orientation = 1 0 0 0 1 0 0 0 -1 ElementDataFile = Ella_26y_V2_2mm.raw
The current release of Maverick, however, requires the images to be in the .mha format. So, perform the conversion using imageMath
imageMath Duke.mhd -W 3 Duke.mha imageMath Ella.mhd -W 3 Ella.mha
Now Merlin can be used to create a scene containing these labelmaps and indexed via those .csv files. Use the standard labelmap import process of Merlin to achieve this.
Create a new version of the woman that is shaped somewhat like the man
To simulate different size people, the virtual woman (Ella) can be registered with the virtual man (Duke) using a deformable (BSpline) transform. In this manner, the woman will take on aspects of the shape of the man. The RegisterImages module accomplishes this
RegisterImages Duke.mha Ella.mha --registration PipelineBSpline --interpolation NearestNeighbor --minimizeMemory --controlPointSpacing 100 --bsplineSamplingRatio 0.02 --resampledImage TallElla.mha --saveTransform TallElla.tfm
All of the above should be on one line. Processing time will vary from 30 minutes to 1 hour, depending on the PC. The result should be two new files: TallElla.mha and TallElla.tfm
The TallElla.mha file can be imported into Merlin.
You can control how closely the woman is deformed into the man by controlling how many BSpline control points are used. More points means more flexibility and ultimately a closer match. The two relevant command-line arguments are --controlPointSpacing and --bsplineSamplingRatio. A smaller controlPointSpacing value means that more bspline control points will be used to span the image. When more control points are used, more samples should be taken to evaluate the metric, i.e., the bsplineSamplingRatio should be increased. Note that computation time can quickly become multiple hours.
View the short and tall ella next to one another in the same volume
First move TellElla 500 mm to the right by editing the file TallElla.mha using vi or another text editor.
vi TallElla.mha
Change line containing the keyword Offset to induce the shift
Offset =