I tried the below code for decoding but still got empty lines.

Some unexpected empty lines or only empty lines?

Empty lines after (almost) all lines you read? chomp!

#!/usr/bin/perl
my $input=$ARGV[0];
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Add use strict; and use warnings;. Ignoring perl's debugging aids just wastes everyone's time.

And finally, whenever you think that perl has encoding problems, show us a hex dump of the input and the output.

Alexander