Algorithm

# Read in the three input files.

# Rebin these files if desired.

# Load the mask set if desired.

foreach (pixel) {
  netFlux(pixel) = 0.0
  foreach (band) {
    netFlux(pixel) = netFlux(pixel) + image(band)(pixel)
  }
}
maxNetFlux = maxval(netFlux)

# Calculate the reference multiplet `ref'.

foreach (pixel) {
  foreach (band) {
    image(band)(pixel) = image(band)(pixel) / ref(band)
  }
}

# Force to thermal -> RGB triplet for each pixel.

# Transform the net flux scale if desired.

# Recombine netFlux and RGB -> RGB.

# Saturation calculation.

# Final colour tweak.

# Separate the filename from the pgplot device `pgDev'.

if (pgDev eq `cps') {
  # Draw the postscript image.
} else
  if (rgbsysstyle eq `polar') then
    # Transform RGB values to polar coordinates.
  end if

  # Assign colour values to 256 bins.

  if (rgbsysstyle eq `polar') then
    # Transform bin colours back from polar coordinates.
  end if

  call pgimag(RGB)
}