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Thanks. I keep forgetting how broken un/pack are in this respect. Having "B6" load the high six bits (of the low byte of the integer) is just non-sensical.

So for the most sane configuration (bits split based on base-2 representation not some "ascending bit order" representation) you have to work harder:

my @fields= unpack "C*", # 16 6-bit numeric values pack "b6"x16, # string of 16 bytes, each holding a 6-bit value map ''.reverse, # 16 6-character ascending-bit strings unpack "a6"x16, # 16 6-character base-2 strings unpack "B*", # 96-character base-2 string "twelve bytes"; # 12-byte packed string print "(@fields)\n"; my $string= pack "B*", # 12-byte packed string pack "a6"x16, # 96-character base-2 string map ''.reverse, # 16 6-character base-2 strings unpack "b6"x16, # 16 6-character ascending-bit strings pack "C*", # string of 16 bytes, each holding a 6-bit value @fields; # 16 6-bit numeric values print "($string)\n";

outputs:

(29 7 29 37 27 7 25 37 8 6 9 57 29 6 21 51) (twelve bytes)

- tye        


In reply to Re^4: pack/unpack 6-bit fields. (insanity) by tye
in thread pack/unpack 6 bit fields. by Anonymous Monk

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