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

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