(Extra)ordinary Article 002: Photo Famine

  • Facebook is big. The site has about 1.44 billion monthly active users. Before we go any further, let’s get some sense of scale. Oftentimes I will gloss over numbers like these without fully comprehending the sheer hugeness of their size. So I will repeat to emphasize: 1.44 billion users. With a B.
  • As a comparison, there are currently about 7.3 billion humans in the world. So, the active monthly user population of Facebook is equivalent to about a fifth of the global population.
  • To put it another way, if you treat the total surface area of the Earth as the global population, the Facebook population would cover a region the size of the following countries combined:
  • Russia
    United States
    Democratic Republic of the Congo
    Greenland (Denmark)
    Saudi Arabia
    South Africa
  • So that is a sizable group.
  • And above all else, this group is doing one thing: posting photos. Over a quarter of a trillion photos (with a T now) are on Facebook with an additional 350 million being added every day. At these kinds of rates, an interesting question arises:
  • Can Facebook run out of possible photos to post?
  • What do I mean by this? Well, photos are split into small partitions call pixels. Given an image size and format, there is a limited amount of real estate and color options for those pixels, making the number of possible images finite. Granted there are a lot options to choose from. But with so many photos being posted, will we exhaust the options anytime soon?
  • We need to consider the formats of the images being posted. There are all sorts of image file formats, but let’s simplify things and see if we can look at how many images are possible for a single image file format and constant image dimensions.
  • Let’s take a look at the PNG file format and the dimensions of a user’s cover photo.
  • Let’s assume that every cover photo being posted has the same dimensions that perfectly fit the size allowed for cover photos. The cover photo dimensions for the desktop are 851 x 315 pixels. So, each cover photo contains 268,065 pixels that can each be a different color.
  • The PNG file format supports several color palettes, but we will consider 24-bit. This means that the color values for each pixel are represented by a 24-bit number, allowing for 16,777,216 different color values per pixel. Multiplying through gives us:
  • 16,777,216 color values per pixel ^ 268,065 pixels
    10^(1,936,694) possible PNG cover photos
  • That is huge.
  • And it would be a curious collection of images. It would have every imaginable image that could fit within its boundaries. The Mona Lisa. The Mona Lisa with red hair. Screenshots of every corner of the globe. Pictures of every human living and dead. Pictures of you doing everything you have done in your entire life. Every word printed in every font and in every color and in every orientation. It would be all-inclusive. It would be like the visual version of pi. A Google Street view for the entire history of recorded and to-be-recorded time. It would be spectacular. The amazing thing is although they are huge, the possibilities are not endless. There is a boundary.
  • We better get posting.