php基于CodeIgniter实现图片上传、剪切功能

/**

• 首页
  */
  public function index() {
  $this->load->view('upload_form',array('error' => ' ' ));
  }

public function do_upload()
{
$config['upload_path'] = './data/uploads/';
$config['allowed_types'] = 'gif|jpg|png';
$config['max_size'] = 100;
$config['max_width'] = 1024;
$config['max_height'] = 768;

$this->load->library('upload',$config);

if ( ! $this->upload->do_upload('userfile'))
{
  $error = array('error' => $this->upload->display_errors());

  $this->load->view('upload_form',$error);
}
else
{
  $data = array('upload_data' => $this->upload->data());

  $this->load->library('image_lib');      

list($width,$height) = getimagesize($data['upload_data']['full_path']);
$config['image_library'] = 'gd2';
$config['source_image'] = $data['upload_data']['full_path'];
$config['maintain_ratio'] = TRUE;
if($width >= $height)
{
$config['master_dim'] = 'height';
}else{
$config['master_dim'] = 'width';
}
$config['width'] = 180;
$config['height'] = 180;
$this->image_lib->initialize($config);
$this->image_lib->resize();

$config['maintain_ratio'] = FALSE;
if($width >= $height)
{
$config['x_axis'] = floor(($width 180 / $height - 180)/2);
}else{
$config['y_axis'] = floor(($height 180 / $width - 180)/2);
}
$this->image_lib->initialize($config);
$this->image_lib->crop();

  $this->load->view('upload_success',$data);
}

}
}