What could be some of the building blocks for a JPG? Without diving into the technical ins-and-outs, I suppose it will likely be which pixel of the image is what colour. And colour to the computer is made up of a mix of red, green and blue.

Now, let’s think back to the earlier post outlining the idea that the output of a computer file is only determined by its decoding program – an image is only an image if the decoding program says it is, it could just as easily be a sound for example. So if each area of colour is a measured amount of it’s constituent colours then by telling the artist how much of each colour to mix together they can create an image in much the same way. 

That’s of course if the guidelines include the instruction to actually mix the colours together and that the colours are red, green and blue.

What happens if the data sent to the artist is the number of the pixel to be coloured and the amounts of red, green and blue listed as a number between 0 and 255, much as the computer would get, but without any indication what the numbers meant. 

Your instructions are: 23 121 45 207 – off you go.