Always worth checking something like this, eventually this is how I was literaly able to discover the binary code on opticording menhirs. (contrast/lightness with legacy option ticked on photoshop – basically to raise up the contrast to a point where, the differences between surrounding pixels is visible).

Eventually this ciphering method is called steganography – meaning the message is sometimes not even encoded, but rather hidden from plain sight, yet possible to be accessed by anyone who know’s where to search the message at.

https://imgur.com/a/0jCYKQR

But this steganography has been hinted, three times by cipsoft:

1. inside the book:
there is more to the surface of these strange menhirs than meets the eye. 

2. at the hidden location in oramond:

Comparing both stones together, an additional hint to the quoted book, more on surface on menhirs – if you look closely on the top of the glass, it has a pixel grid/filter on it – so the npcs inside the game would be able to see it.

3. On facebook post, rasising again the attention to the quest, plus refering to the stone itself (at that time noone know if the stone was important or even hiddin something)

Here some other attempts similar to yours I’ve done in past on warlord sword, tibia logo and the tibia map:

Which quickly looks like it nothing – however, as we have quite a number of sprites added to game, there is still a chance that there are messages hidden at plain sight, embedded into them, that noone noticed for years. After all, tibia is basing on pixel art.