pouët.net

@randomi, the idea is nearly identical to what ilmenit does in Mona. The image is generated in a loop with 64 iterations. Let N be the iteration number (N=64, 63, ..., 1). During each iteration I plot on the screen 4*N 2x2 pixel "points" with random coordinates X and Y. The plotting is done using XOR operation, so that mistakes can be potentially corrected. To add a touch of sophistication to the image I also plot 256 totally random _pixels_ after each iteration. My PRNG is a 24 bit Galoius LFSR with a bit mixer hacked at the end. The lower 16 bits of PRNG are seeded during each iteration (this is our "data"); the higher 8 bits are carried over from the previous iteration. The starting value of the higher 8 bits is an additional data value. Since the last few iterations do not plot many points, they are not seeded properly. Overall, the image is stored as 62*2+1=125 bytes of data. The lossy compression ratio here is lower compared to ilmenit's case (128*96/8 : 125 ~ 12.3x).

The specific choice of seeds, just like in the ilmenit's case, is obtained by an iterative brute-force search on a PC. I went through several configurations of the plotting algorithm to improve the overall image quality. Once I settled on a particular configuration, I went through some 5*256*64*65536 seed values (number 5 reflects the fact that my PRNG allowed 5 distinct feedback polynoms for the maximum period). The best looking image was then chosen manually. The overall computation took about one and a half days on 7 cores. I am confident that both the image quality and the speed of computation could have been further improved, but I ran out of time.

The menacing appearing and disappearing into the static is achieved by running an identical plotting loop with an incorrect seed value twice; during the first run the image gets completely corrupted by the noise, during the second the noise completly cancels itself out.

sim, I understand what you are saying. It is not particularly pleasant to be a Russian citizen these days. I find it impossible to ignore what is going on in Ukraine at the moment. I wanted to send this to a party in Russia, which is a part of a fairly large animation fest, i.e. far from demoscene-only. Thus, it could not have been any kind of explicit political statement. So I went for something ambivalent, menacing and, hopefully, reminiscent of the 1984 Apple advert. I do not think it was fully successful, in that I could not match the colour scheme of the Apple advert for technical reasons and also because you are not the only person to ask me this question. Just be assured - this was not a decision taken lightly.