scripts/builtin/psnr.dml

#-------------------------------------------------------------
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# Returns the peak signal to noise ratio
#
# https://en.wikipedia.org/wiki/Peak_signal-to-noise_ratio
#
# INPUT:
# --------------------------------------------------------------------------------
# X      First Matrix to compare
# Y      Second Matrix to compare
# --------------------------------------------------------------------------------
#
# OUTPUT:
# -----------------------------------------------------------------------------------------------
# Z      The peak signal to noise ratio
# -----------------------------------------------------------------------------------------------

m_psnr = function(Matrix[Double] X, Matrix[Double] Y) return (Matrix[Double] Z) {
  [MSE, NN] = mse(X=X, Y=Y)
  Z = 10 * log(max(X)^2 / MSE, 10)
}