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

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Text this: Three-dimensional VLC indoor positioning system using smart device camera receiver with image processing technique