SphinxExamples/src/Filtering/Thresholding/ThresholdAnImageUsingOtsu/Code.py

#!/usr/bin/env python
 
# 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
#
#        https://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.
 
import itk
import argparse
 
parser = argparse.ArgumentParser(description="Threshold An Image Using Otsu.")
parser.add_argument("input_image")
parser.add_argument("output_image")
parser.add_argument("number_of_histogram_bins", type=int)
parser.add_argument("number_of_thresholds", type=int)
parser.add_argument("label_offset", type=int)
args = parser.parse_args()
 
PixelType = itk.UC
Dimension = 2
 
ImageType = itk.Image[PixelType, Dimension]
 
reader = itk.ImageFileReader[ImageType].New()
reader.SetFileName(args.input_image)
 
thresholdFilter = itk.OtsuMultipleThresholdsImageFilter[ImageType, ImageType].New()
thresholdFilter.SetInput(reader.GetOutput())
 
thresholdFilter.SetNumberOfHistogramBins(args.number_of_histogram_bins)
thresholdFilter.SetNumberOfThresholds(args.number_of_thresholds)
thresholdFilter.SetLabelOffset(args.label_offset)
 
rescaler = itk.RescaleIntensityImageFilter[ImageType, ImageType].New()
rescaler.SetInput(thresholdFilter.GetOutput())
rescaler.SetOutputMinimum(0)
rescaler.SetOutputMaximum(255)
 
writer = itk.ImageFileWriter[ImageType].New()
writer.SetFileName(args.output_image)
writer.SetInput(rescaler.GetOutput())
 
writer.Update()