Ardil:

I think I'll have to go with ELESHEVA on this one. Sure you could do it with regexes, but the JSON module doesn't seem to difficult to work with:

#!/usr/bin/perl
use strict;
use warnings;
use JSON;

while (my $line = <DATA>) {
    my $data = decode_json $line;
    if ($data->[0] == -1
        and $data->[1] == -1
        and $data->[2] == 32
        and $data->[3] == 45
    ) {
        $data = [ 1, 39, 2, 45 ];
    }
    print encode_json($data), "\n";
}
__DATA__
[-1,-1,32,45]
[-1,-1,-1,-1]
[-1,-1,0,28]
[0,27,0,29]
[0,28,0,30]
[download]

On my machine, it produces (as expected):

$ perl 890521.pl
[1,39,2,45]
[-1,-1,-1,-1]
[-1,-1,0,28]
[0,27,0,29]
[0,28,0,30]
[download]

Update: Fixed attribution.

...roboticus

When your only tool is a hammer, all problems look like your thumb.