Is the Avengers 4 title hidden in a cryptic photo?

The black-and-white photo, captioned "Look hard...", apparently shows Joe Russo sat in a director's chair on an empty sound stage.

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Marvel fans are convinced that there are hidden letters in the photo, but there are different theories floating around on social media about what exactly they might spell out...

https://twitter.com/Russo_Brothers/status/1042411495072645120?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042411495072645120&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

One popular theory is that the word 'ENDGAME' is hidden in the image, a reference to Doctor Strange line in Infinity War.

https://twitter.com/Patrick83Smith/status/1042420598478131200?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042420598478131200&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

https://twitter.com/brianonthescene/status/1042432839080464385?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042432839080464385&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

Others believe they can see four 'A's, indicating Avengers 4.

https://twitter.com/Jimmy2495/status/1042413612801945606?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042413612801945606&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

After that, the theories become increasingly niche — including a 'Avengers: Alabama' film and a surprise Homer Simpson cameo...

https://twitter.com/sebworthy/status/1042464021998460935

https://twitter.com/AidarSM/status/1042424080740302850?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042424080740302850&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

https://twitter.com/biohazard444/status/1042412972595929088?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042412972595929088&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

However, it seems that most fans are just as stumped as we are.

https://twitter.com/ZeusLFC/status/1042412672145350657?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042412672145350657&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

https://twitter.com/themarcoramos/status/1042425374066397186?ref_src=twsrc%5Etfw%7Ctwcamp%5Etweetembed%7Ctwterm%5E1042425374066397186&ref_url=https%3A%2F%2Fwww.cnet.com%2Fnews%2Frusso-brothers-tease-avengers-4-title-with-instagram-photo%2F

Come on, Russo brothers, give us a hint.