s (note: s-slash-s) Show me where in the bible it talks about computers!! /s
He did not tell us exactly how that image would come about, just that it would.
Now if the world now has the computer technology to create an image of a person that can speak, and that technology enables Revelation 13:15 to come to pass, which it will, despite all the denials of those who equate the Bible with Aesop's fables, then intelligent, reasonable people, especially those who believe that God tells the truth, can see that technology and know that Revelation 13:15 can now be fulfilled.
God doesn't have to say anything about computers. He told us what will happen, and knew that His people who would be living in the generation in which the prophecy would be fulfilled would see the stage being set and would know what is happening.
It's really just that simple.