Robuta

https://patents.google.com/patent/US8612765B2/en?oq=US+Patent+%238%2C612%2C765 US8612765B2 - Security based on subliminal and supraliminal channels for data objects - Google... This invention relates to security for data objects; more particularly, the present invention relates to improved security based on subliminal and supraliminal... based on