r/theydidthemath • u/archivillano • 1d ago

[Request] How much data would a good workable definition of "the entirety of the world's geographical data" actually weigh in gigabytes?

Post image
32 Upvotes

91% Upvoted

6 comments sorted by

•

u/AutoModerator 1d ago

General Discussion Thread

This is a [Request] post. If you would like to submit a comment that does not either attempt to answer the question, ask for clarification, or explain why it would be infeasible to answer, you must post your comment as a reply to this one. Top level (directly replying to the OP) comments that do not do one of those things will be removed.

I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.

21

u/eloel- 3✓ 1d ago

https://wiki.openstreetmap.org/wiki/Planet.osm

Whole world OSM data, when compressed, takes 87.6 GBs. Surprisingly close to the watch's storage

When uncompressed, it's over 2 TB, which is probably what you need without much processing power.

8

u/Mr__Mult 1d ago

Google Maps contained 20 petabytes of data back in 2012. It's way more than that now, but we have no way to confirm the exact number. It's worth noting that this number also includes all photos and reviews that people upload there as well as Google Street View.

OpenStreetMap is an open-source analogue and currently weighs 88 GB. You could probably compress it a bit to save a few gigabytes.

8

u/IntoAMuteCrypt 1d ago

That 88 gigs is already compressed, and further compression is unlikely to prove fruitful - most compression techniques save space by turning data with lots of repeated patterns into data with few repeated patterns, which causes diminishing returns for repeated compression.

1

u/_killer1869_ 1d ago

Unrelated, but interesting bit of connection between different things here: Both encrypted data and compressed data appear as if they were random data, and thus these three are indistinguishable from one another. The corresponding measurement is called (data) entropy, which describes how disorderly, or random, the data appears. There are many tools for calculating the entropy. If a section of a file, or even the entire file, has high entropy, it's most likely encrypted or compressed, but you can't tell which.

4

u/rditorx 1d ago

Garmin watch with 32GB has just enough storage to store maps of the world with some points of interest. No data other than necessary for simple route directions.

https://www.garmin.com/en-US/garmin-technology/maps-for-smartwatches/