SimpleITK  
ImageRegistrationMethod2/ImageRegistrationMethod2.R
#=========================================================================
#
# Copyright NumFOCUS
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0.txt
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
#=========================================================================
# Run with:
#
# Rscript --vanilla ImageRegistrationMethod2.R fixedImageFilter movingImageFile outputTransformFile
#
library(SimpleITK)
commandIteration <- function(method)
{
msg <- paste(method$GetOptimizerIteration(), "=",
method$GetMetricValue(), ":",
method$GetOptimizerPosition(), "\n" )
cat(msg)
}
args <- commandArgs( TRUE )
if (length(args) != 3) {
stop("3 arguments expected - fixedImageFilter, movingImageFile, outputTransformFile")
}
pixelType <- 'sitkFloat32'
fixed <- ReadImage(args[[1]], pixelType)
fixed <- Normalize(fixed)
fixed <- DiscreteGaussian(fixed, 2.0)
moving <- ReadImage(args[[2]], pixelType)
moving <- Normalize(moving)
moving <- DiscreteGaussian(moving, 2.0)
R <- ImageRegistrationMethod()
R$SetMetricAsJointHistogramMutualInformation()
R$SetOptimizerAsGradientDescentLineSearch(learningRate=1.0,
numberOfIterations=200,
convergenceMinimumValue=1e-5,
convergenceWindowSize=5)
R$SetInitialTransform(TranslationTransform(fixed$GetDimension()))
R$SetInterpolator('sitkLinear')
R$AddCommand('sitkIterationEvent', function() commandIteration(R))
outTx <- R$Execute(fixed, moving)
cat("-------\n")
outTx
cat("Optimizer stop condition:", R$GetOptimizerStopConditionDescription(), '\n')
cat("Iteration:", R$GetOptimizerIteration(), '\n')
cat("Metric value:", R$GetMetricValue(), '\n')
WriteTransform(outTx, args[[3]])