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           _    _                ___     _____    
  ____    | || | ||   ____      / _ \\  |  __ \\  
 |    \\  | || | ||  |    \\   / //\ \\ | |  \ || 
 | [] ||  | \\_/ ||  | [] ||  |  ___  ||| |__/ || 
 |  __//   \____//   |  __//  |_||  |_|||_____//  
 |_|`-`     `---`    |_|`-`   `-`   `-`  -----`   
 `-`                 `-`

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Text this: Optical Encryption and Authentication Based on Phase Retrieval and Sparsity Constraints