WP 5.3 Removing Default Wordpress Image Sizes

Question

I've found several examples where they use the intermediate_image_sizes_advanced filter to unset the default WP image sizes that are generated whenever a user uploads a new image to the media library. This filter, on a brand new install with no plugins will not be called at all.

Calling get_intermediate_image_sizes() spits out the following array:

[05-Feb-2020 17:29:55 UTC] Array
(
    [0] => thumbnail
    [1] => medium
    [2] => medium_large
    [3] => large
    [4] => 1536x1536
    [5] => 2048x2048
)

Where did 1536x1536 come from? Where did 2048x2048 com from?

I later tried to call remove_image_size('size') from within an init action and this only worked for the two new sizes mentioned above. The other default sizes still remained:

[05-Feb-2020 17:30:26 UTC] Array
(
    [0] => thumbnail
    [1] => medium
    [2] => medium_large
    [3] => large
)

Does anyone know what's going on here? Has something changed?

Answer 1

Using the intermediate_image_sizes_advanced filter was not working for me. However, the intermediate_image_sizes works and the $default_sizes array is an indexed array, not an associative array. In every single example that I have found for using the intermediate_image_sizes_advanced filter, the answer's are unsetting the image sizes from an associative array.

The following worked for me in WP 5.3:

add_filter( 'intermediate_image_sizes', 'remove_default_img_sizes', 10, 1);

function remove_default_img_sizes( $sizes ) {
  $targets = ['medium', 'medium_large', 'large', '1536x1536', '2048x2048'];

  foreach($sizes as $size_index=>$size) {
    if(in_array($size, $targets)) {
      unset($sizes[$size_index]);
    }
  }

  return $sizes;
}

Here's a link to the function that adds the two additional sizes since 5.3 with an explanation to why I was able to remove them using remove_image_size.

Answer 2

you can used below code to remove image sizes is placed in the appropriate location within your theme or plugin.

after_setup_theme action hook used to achieve functionality.

function remove_default_image_sizes() {
    remove_image_size('thumbnail');
    remove_image_size('medium');
    remove_image_size('medium_large');
    remove_image_size('large');
}
add_action('after_setup_theme', 'remove_default_image_sizes');

Answer 3

In addition: the 1536x1536 and 2048x2048 sizes are not removed by the intermediate_image_sizes-filter. To remove them, I just use the remove_image_size-method.

add_action( 'init', 'wpdocs_remove_default_additional_image_sizes' );
function wpdocs_remove_default_additional_image_sizes() {
    remove_image_size( '1536x1536' );
    remove_image_size( '2048x2048' );
}

(from: https://developer.wordpress.org/reference/functions/_wp_add_additional_image_sizes/#comment-6722)