#-------------------------------------------------------------
#
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you 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
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
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# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
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#-------------------------------------------------------------

# The Image Posterize function limits pixel values to 2^bits different values in the range [0, 255].
# Assumes the input image can attain values in the range [0, 255].
#
# INPUT:
# -------------------------------------------------------------------------------------------
# img_in  Input image
# bits    The number of bits keep for the values.
#         1 means black and white, 8 means every integer between 0 and 255.
# -------------------------------------------------------------------------------------------
#
# OUTPUT:
# ---------------------------------------------------------------------------------------------
# img_out  Output image
# ---------------------------------------------------------------------------------------------

m_img_posterize = function(Matrix[Double] img_in, Integer bits) return (Matrix[Double] img_out) {
  img_out = (img_in %/% 2^(8 - bits)) * (2^(8 - bits))
}
