File:population-earth1.png

Summary

An isochromic map of the world population, superimposed on a pastel-color background that shows land, water, and borders.

Everything in black is population.

Note: Some border lines may be completely obscured by populations (especially India's borders with Bangladesh, Pakistan, and Bhutan). Still better than the opposite (letting the border lines obscure the populations).

Note: Be careful not to confuse small blue dots (lakes) for small black dots (population). In the next version I'll try to make the blue parts lighter (or erase small bodies of water) so this doesn't happen.

Methodology

Image generator code:

# load files
pop << data/population.data-float64-8640x4320
earth << data/blue-marble-posterized.png
borders << data/borders-black-on-white.png
borders @@ negative

# resize things to fit the 'earth' background
pop :: $earth.r # the '$' preserves the total population
borders :: earth.r
borders *= 6 # brighten the lines

# lighten the background
earth.r += 0.6
earth.g += 0.6
earth.b += 0.6

# show the borders in white
earth.r >= borders
earth.g >= borders
earth.b >= borders

# show the population in black
pop /= 800000 # max people per pixel
pop @@ spread
pop @@ negative
earth.r <= pop
earth.g <= pop
earth.b <= pop

# save
earth >> data/population-earth1.png