Mindhue Studio

Printmaking, conceptual and installation art

We Can Do It, in CGA, as a Tweet

So, going even further into Tweet image compression, I thought, “Let’s add some color.” A good way to get decent compression is to limit the number of colors you use to a specific quantity. You don’t have to encode the numbers, you just refer to a common table of values that never change. This way, you can get a range of hues in your images. But most “indexed” color formats actually save the color index with the pixel information. To save that overhead, I should use a palette that would be easy to find in the wild.

Enter the CGA palette. This will be familiar to people who grew up in the early days of IBM PC systems, where a “color” game might include cyan, magenta, white and black. That would have been the 2-bit version of the 4-bit palette used in IBM’s Color Graphics Array. The full range of this palette can be seen thusly:

Taking these colors as their hex values (0,1,2,3,4,5,6,7,8,9,A,B,C,D,E,F), I could encode a color image of at least 10 x 13 pixels. Which is what I did. I could even include a blurb to indicate the compression scheme!

Right there is the lovely image presented at full size. Of course, it’s the iconic Rosie the Riveter poster from WWII, with the inspirational message of “We Can Do It!” In the interest of looking at the pixels, here’s a larger version:

Here’s the pixel map in CGA values:

1111111111
179BFB7FB1
6611111116
4C76EEEEEE
4C7CE72EEE
ECECEEAAEE
E777EE2AEE
E3337CECDE
E3388C7C6E
611117ECCE
600000865C
E800088666
8800088888

And, finally, here’s the tweet that encodes it all:

1111111111179BFB7FB166111111164C76EEEEEE4C7CE72EEEECECEEAAEEE777EE2AE
EE3337CECDEE3388C7C6E611117ECCE600000865CE8000886668800088888 CGA 10x13

2 Comments on “We Can Do It, in CGA, as a Tweet”

  1. Pingback: Animated Twitter Graphic (.atg?) | Mindhue Studio

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