Apr 20: At this size, each pixel is about 80.73 people.

Apr 21: One flaw I've found in this method is that it gets a little iffy when the numbers being encrypted get close to a power of ten— 9999 becomes 99995, 9998 becomes 99990, etc. If you need to send out a message that's all nines, it defeats the purpose a bit.

Apr 23: Turns out I've been spelling "polka dot" incorrectly for all of these years. The term is two words, not a single compound word. I've just consulted three separate 20th Century dictionaries and they all agree on this. The important thing is that she seems to be enjoying the attention, at least.