...
    @samples = split(//,$_);

    while (@samples) { 
        print OUTFILE sprintf("0x%02x%02x",map{ord}reverse splice @sam
+ples,0,2 ).", ";
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ord returns the ordinal number (ASCII value) of a char in decimal, i.e. a number between 0..255. If there's a 'f' in that stream, that will be converted into 102. sprintf("0x%02x",ord "f") gives 0x66.

But there are more elegant ways to do this. See pack and unpack.

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}