Created a New size image

if you want to create a new image size and enable to choose it via selection:

// add new size or overwrite an existing size
add_image_size( 'new-size', 2000, 500, true );

// make the new size available in the media library (and image element etc.)
add_filter( 'image_size_names_choose', 'my_custom_sizes' );

function my_custom_sizes( $sizes ) {
    return array_merge( $sizes, array(
        'new-size' => __( 'New Size' ),
    ) );
}

sorry – yes
and the “true” concerns to crop behavior
and i think that choose is not necessary if you overwrite an existing one

ps you can find a lot of nice functions in function-set-avia-backend.php
and on line 546 the add_image_size function

• This reply was modified 7 years, 6 months ago by Guenni007.

PPS: if you have to get for your old uploaded files the new format – you might use a plugin like force regenerate thumbnails