Submit handler for adding a new image style.
function image_style_add_form_submit($form, &$form_state) {
$style = array(
'name' => $form_state['values']['name'],
'label' => $form_state['values']['label'],
);
$style = entity_create('image_style', $style);
$style
->save();
drupal_set_message(t('Style %name was created.', array(
'%name' => $style
->label(),
)));
$form_state['redirect'] = 'admin/config/media/image-styles/edit/' . $style
->id();
}