use strict;
use warnings;
use utf8;

use Encode qw( decode );

my $chars_src = "采样速率太高";
my $bytes_dst;

{
   open my $fh, '>:utf8', \$bytes_dst;
   print $fh $chars_src;
}

my $chars_dst = decode('utf8', $bytes_dst);

binmode(STDOUT, ':utf8');
print("$chars_src\n");
print("$chars_dst\n");