Here's an automated way to create the lookup table. Bit-counting function assumes data passed as raw binary string of any length, but test statements show a way to convert from hex-digit text string if it isn't. 

>perl -wMstrict -le
"my @setbits;
 for my $byte (0 .. 255) {
   my $bits = unpack 'B*', chr $byte;
   my @offsets;
   push @offsets, $-[1] while $bits =~ m{(1)}xmsg;
   push @setbits, [ @offsets ];
   }
 sub find_set_bits {
   my ($raw_binary) = @_;
   my @offsets;
   my $offset = 0;
   for my $byte (unpack 'C*', $raw_binary) {
     push @offsets, map $_ + $offset, @{ $setbits[$byte] };
     $offset += 8;
     }
   return @offsets;
   }
 my $str = qq{ 01 02 03 \n 04 00 E0 0a 00 00 00 00 00 00 00 00 00 \n};
 (my $hexdigits = $str) =~ s{[^[:xdigit:]]}{}xmsg;
 my $raw = pack 'H*', $hexdigits;
 my @ones_offsets = find_set_bits($raw);
 print qq{'$str'};
 print qq{no 1-bits found} unless @ones_offsets;
 print qq{1-bit found at offset $_} for @ones_offsets;
"
' 01 02 03
 04 00 E0 0a 00 00 00 00 00 00 00 00 00
'
1-bit found at offset 7
1-bit found at offset 14
1-bit found at offset 22
1-bit found at offset 23
1-bit found at offset 29
1-bit found at offset 40
1-bit found at offset 41
1-bit found at offset 42
1-bit found at offset 52
1-bit found at offset 54

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In reply to Re^2: Working with BIG binary fields by AnomalousMonk
in thread Working with BIG binary fields by juju

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