#-------------------------------------------------------------
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# to you under the Apache License, Version 2.0 (the
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#-------------------------------------------------------------

# Image Shear
# Applies a shearing transformation to an image.
# Uses nearest neighbor sampling.
#
# INPUT PARAMETERS:
# ---------------------------------------------------------------------------------------------
# NAME       TYPE   DEFAULT MEANING
# ---------------------------------------------------------------------------------------------
# img_in     Matrix ---     Input image as 2D matrix with top left corner at [1, 1]
# shear_x    Int    ---     Shearing factor for horizontal shearing
# shear_y    Int    ---     Shearing factor for vertical shearing
# fill_value Double ---     The background color revealed by the shearing

# RETURN VALUES
# ---------------------------------------------------------------------------------------------
# img_out    Matrix ---     Output image as 2D matrix with top left corner at [1, 1]
# ---------------------------------------------------------------------------------------------

m_img_shear = function(Matrix[Double] img_in, Double shear_x, Double shear_y, Double fill_value) return (Matrix[Double] img_out) {
  img_out = img_transform(img_in, ncol(img_in), nrow(img_in), 1, shear_x, 0, shear_y, 1, 0, fill_value)
}
