Using gform_field_value with a global array?

I posted a similar thread, but I'll take a different approach:

I've got various arrays available within my template, and want to put some of that data into the form being integrated into that same page:

Viewing raw
<?php echo $image->filename ?>
<?php echo $iptc['location'] ?>

So this works:

<?php add_filter('gform_field_value_image_filename', 'get_filename'); function get_filename($value){$variable = "FileName" ;return (string) $variable; } ?>
<?php echo $image->filename ?>
    <?php gravity_form(1, false, false, false, '', false); ?>

This however, will not: (I get nothing)

<?php  add_filter('gform_field_value_image_filename', 'get_filename'); function get_filename($value){$variable = $image->filename ;return (string) $variable; } ?>
<?php echo $image->filename ?>
    <?php gravity_form(1, false, false, false, '', false); ?>

Or simply this doesn't work. (I get nothing)

<?php  add_filter('gform_field_value_image_filename', 'get_filename'); function get_filename($value) ; return $image->filename;  ?>
<?php echo $image->filename ?>
    <?php gravity_form(1, false, false, false, '', false); ?>

The instances of the plain echo work just fine. So it's available "right there".

How do I get that information *into* the "get_filename" loop? It's obviously global.

Otherwise, I have no clue what the purpose of this routine to pre-load data via the function is for- if all it works is with a hard coded "return "this data" because you can do that directly in Gravity Forms.

Here is the whole page, with the Gravity Form call at the bottom:

http://pastebin.com/b2eiNg67

Hi guys,

This is a PHP scope issue. You need to declare that your global variable is available inside the hooked function, like so:

[php]
add_filter('gform_field_value_image_filename', 'get_filename');
function get_filename($value){
    global $image;
    ...

Now it will be available in the function per your second two examples.