First, let's show the picture itself:
I suppose that this is the biggest (763x65500) image that has ever been published on Steem. It was done by processing this video from YouTube:
The algorithm is as follows: a ring of pixels is taken from each frame at some radius from the center and "unbends" into a line, forming a row of the image:
Now I'm working on translating the algorithm from ActionScript (which is a legacy of the dead Flash) to Python. I will publish the source code. Stay with me, friends!
P.S. In fact, Steemit limits the images even from external sources. It refused to insert a large picture in its original size and I had to cut it into several parts. Because of this, the quality was significantly lost. So best way is download the original image from my Google Drive.