Thumbs images upload error in codeigniter - php

Question

<?php
$image = array(
'name' => 'userfile',
'id' => 'userfile',
);
$submit = array(
'name' => 'submit',
'id' => 'submit',
'value' => 'Upload'
);
?>
<?php echo form_open_multipart('upload/upload_image', 'id=upload_file'); ?> <!-- must autoload form helper for this -->
<?php echo form_upload($image); ?>
<?php echo form_submit($submit); ?>
<?php echo form_close(); ?>
this is main.php in view folder
<?php
class Upload_model extends CI_Model{
var $original_path;
var $resized_path;
var $thumbs_path;
//initialize the path where you want to save your images
function __construct(){
parent::__construct();
//return the full path of the directory
//make sure these directories have read and write permessions
$this->original_path = realpath(APPPATH.'../uploads/original');
$this->resized_path = realpath(APPPATH.'../uploads/resized');
$this->thumbs_path = realpath(APPPATH.'../uploads/thumbs');
}
function do_upload(){
$this->load->library('image_lib');
$config = array(
'allowed_types' => 'jpg|jpeg|gif|png', //only accept these file types
'max_size' => 2048, //2MB max
'upload_path' => $this->original_path //upload directory
);
$this->load->library('upload', $config);
$image_data = $this->upload->data(); //upload the image
print_r($image_data);
if($image_data){
echo "uploaded";
}else {echo "not upload";}
//your desired config for the resize() function
$config = array(
'source_image' => $image_data['full_path'], //path to the uploaded image
'new_image' => $this->resized_path, //path to
'maintain_ratio' => true,
'width' => 128,
'height' => 128
);
//this is the magic line that enables you generate multiple thumbnails
//you have to call the initialize() function each time you call the resize()
//otherwise it will not work and only generate one thumbnail
$this->image_lib->initialize($config);
$this->image_lib->resize();
$config = array(
'source_image' => $image_data['full_path'],
'new_image' => $this->thumbs_path,
'maintain_ratio' => true,
'width' => 36,
'height' => 36
);
//here is the second thumbnail, notice the call for the initialize() function again
$this->image_lib->initialize($config);
$this->image_lib->resize();
}
}
this is my model
and controller only load main.php that allow me select image click submit and then controller call model above to load image
the problem is --> there are no error generate but image and thumbs not uploaded to directory why please?