Can't Resize Photo in Codeigniter - codeigniter

Question

I need to resize photo when uploaded into path, but the photo can't resize, please correct me about my code here:
private function _do_upload()
{
$config['upload_path'] = './uploads/';
$config['allowed_types'] = '*';
$config['file_name'] = slug($this->input->post('judul')).'_'.time();
$config['image_library'] = 'gd2';
$config['quality'] = '20%';
$config['remove_space'] = TRUE;
$config['create_thumb'] = TRUE;
$config['maintain_ratio'] = TRUE;
$config['width'] = 75;
$config['height'] = 50;
$this->load->library('image_lib', $config);
$this->image_lib->initialize($config);
$this->image_lib->resize();
$this->load->library('upload',$config);
if (!$this->upload->do_upload('photo')) {
$this->session->set_flashdata('msg', $this->upload->display_errors('',''));
redirect('backoffice/tambah_video');
}
return $this->upload->data('file_name');
}

Answer 1

Please specify new image path and try to save.
$config['new_image'] = '/path/to/new_image.jpg';
Also make sure that you have GD library enabled.

Answer 2

You need to do resize() after do_upload(), and separate the configs for the image_lib and upload libraries, now they are mixed.
Try this:
private function _do_upload()
{
// step 1: upload
$upload_config['upload_path'] = './uploads/';
$upload_config['allowed_types'] = '*';
$upload_config['file_name'] = slug($this->input->post('judul')).'_'.time();
$this->load->library('upload', $upload_config);
if (!$this->upload->do_upload('photo')) {
$this->session->set_flashdata('msg', $this->upload->display_errors('',''));
redirect('backoffice/tambah_video');
}
// step 2: resize
$resize_config['source_image'] = $this->upload->upload_path . $this->upload->file_name; // uploaded file path
$resize_config['image_library'] = 'gd2';
$resize_config['quality'] = '20%';
$resize_config['remove_space'] = TRUE;
$resize_config['create_thumb'] = TRUE;
$resize_config['maintain_ratio'] = TRUE;
$resize_config['width'] = 75;
$resize_config['height'] = 50;
$this->load->library('image_lib', $resize_config);
$this->image_lib->resize();
return $this->upload->data('file_name');
}
If $resize_config['create_thumb'] = TRUE; the name of the small image will be suffixed _thumb. If you need to overwrite the uploaded image, do $resize_config['create_thumb'] = FALSE;. See also the thumb_marker and new_image configs in the official documentation.