Weird problem concerning home made library

[eluser]boudewijn[/eluser]
Hi all,

first off: I'm pretty new to CI so I hope im posting this in the right place and in the right way. Anyway, i'm having a strange problem concerning a resize library i wrote.

this is the code

Code:

<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Resize {

    function resize_book_large($data)
    {
        
        $file_name = element('file_name', $data['upload_data']);
        $path = 'uploads/'.$file_name;
        
        $CI =& get_instance();
    
        $config['image_library'] = 'gd2';
        $config['source_image']    = $path;
        $config['new_image'] = 'uploads/thumbs/large_'.$file_name;
        $config['create_thumb'] = TRUE;
        $config['maintain_ratio'] = TRUE;
        $config['width']     = 300;
        $config['height']    = 450;
        
        $CI->load->library('image_lib', $config);
        
        echo $CI->image_lib->resize();
            
        if ( ! $CI->image_lib->resize())
        {
            echo $CI->image_lib->display_errors();
        }
    }
    
    function resize_book_small($data)
    {
        
        $file_name = element('file_name', $data['upload_data']);
        $path = 'uploads/'.$file_name;
        
        $CI =& get_instance();
        
        $config['image_library'] = 'gd2';
        $config['source_image']    = $path;
        $config['new_image'] = 'uploads/thumbs/small_'.$file_name;
        $config['create_thumb'] = TRUE;
        $config['maintain_ratio'] = TRUE;
        $config['width']     = 150;
        $config['height']    = 175;
        
        $CI->load->library('image_lib', $config);
        
        echo $CI->image_lib->resize();
            
        if ( ! $CI->image_lib->resize())
        {
            echo $CI->image_lib->display_errors();
        }
                
    }

    
}

?>

now i loaded $this->load->library('Resize'); in my controller, so far so good

the problem is however that
when i try to call upon

$this->resize->resize_book_small($data);
$this->resize->resize_book_large($data);

only the first one works (in this case _small, but if i shift large up, _large works).
By works i mean giving me the thumbnail in the directory i specified.

To make it even stranger:

Code:

echo $CI->image_lib->resize();

gives me TRUE for both functions

so it seems that they both work, but only the first one is giving me an output file...

I tried alot of things but im hopeless atm.
Hope someone can help and that this is clear enough!

cheers