@horhik The program used for these animations is glitchcat (https://github.com/kuviman/glitchcat), on the Arch Linux Repository you can find it as the glitchcat-git package. I just send a random ASCII art to the program in the last line of ~/.zshrc (or ~/.bashrc if you prefer bash) and it automatically displays the animation on start.
To create the ASCII art I used a program called Jave, which can take an image and create a text version of it.