You should try to use the new Drupal functions wherever possible.
Instead, use:
use Drupal\file\Entity\File;
use Drupal\image\Entity\ImageStyle;
$fid = 123;
$file = File::load($fid);
$image_uri = ImageStyle::load('your_style-name')->buildUrl($file->getFileUri());
Edited as per [
[To see links please register here]
][1]:
$original_image = 'public://images/image.jpg';
// Load the image style configuration entity
use Drupal\image\Entity\ImageStyle;
$style = ImageStyle::load('thumbnail');
$uri = $style->buildUri($original_image);
$url = $style->buildUrl($original_image);
[1]:
[To see links please register here]