change text box to drop down list

[richo3880]

<!-- image subdirectory fields added  here -->
         <tr>
         <td class="main"><?php echo TEXT_IMAGE_DIRECTORY . '<br><small>' . TEXT_IMAGE_PATH_NOTE . '</small>'; ?></td>
         <td class="main"><?php echo tep_draw_separator('pixel_trans.gif', '24', '15') . ' ' . tep_draw_input_field('image_subdirectory', $image_subdirectory);
             if (SHOW_DIR_CHECKBOX == 'true') { echo '   ' . TEXT_IMAGE_PATH_CHECKBOX . ' ' . 
			tep_draw_checkbox_field(new_dir , $value = $new_dir, $checked = false, $parameters = '');} ?>
         </td>
         <tr>
         <td colspan="2"><?php echo tep_draw_separator('pixel_trans.gif', '1', '0'); ?></td>
         </tr>
<!-- image subdirectory addition finished --> 

 

from the code above, how to change the input text box to a drop down list?i have sub folders in the image directory that i need them hard coded here....