Add custom image sizes in WordPress

August 26, 2013

add_theme_support( 'post-thumbnails' );
add_image_size('card-image', 320, 240,true);

add_filter('image_resize_dimensions', 'image_resize_dimensions', 10, 6);

function image_resize_dimensions($default, $orig_w, $orig_h, $new_w, $new_h, $crop){
 if ( !$crop ) return null; // let the wordpress default function handle this

$aspect_ratio = $orig_w / $orig_h;
 $size_ratio = max($new_w / $orig_w, $new_h / $orig_h);

$crop_w = round($new_w / $size_ratio);
 $crop_h = round($new_h / $size_ratio);

$s_x = floor( ($orig_w - $crop_w) / 2 );
 $s_y = floor( ($orig_h - $crop_h) / 2 );

return array( 0, 0, (int) $s_x, (int) $s_y, (int) $new_w, (int) $new_h, (int) $crop_w, (int) $crop_h );
}

Tags: php, wordpress