I managed to convert the section in your example into a string in JSON notation using the following:

my $section = [ 
    [ "image1.gif" , "mark('a' ,1)" ],
    [ "image2.gif" , "mark('a' ,2)" ],
];

my $parsed = '[ ' . 
             join( ' , ', map { '[ "' . join('" , "', @$_) . '" ]' } @
+$section ) .
             ' ]';
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$parsed will contain the following string:

[ [ "image1.gif" , "mark('a' ,1)" ] , [ "image2.gif" , "mark('a' ,2)" 
+] ]
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which is (I think) what you want. (There's an extra square bracket in your example, which I omitted.)

It does use map, among other things, though I'm not sure it qualifies for "clean-lookin". I found a CPAN module called JSON which produced the same result more cleanly, and would probably be easier to maintain:

use JSON;

my $json = JSON->new;

my $section = [
    [ "image1.gif" , "mark('a' ,1)" ],
    [ "image2.gif" , "mark('a' ,2)" ],
];

my $parsed = $json->objToJson( $section );
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