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<?php
// =================================================================
// ====== Custom image sizes
// =================================================================

// Add new image sizes
function custom_image_sizes( $image_sizes ) {
  // get the custom image sizes
  global $_wp_additional_image_sizes;
  // if there are none, just return the built-in sizes
  if ( empty( $_wp_additional_image_sizes ) )
    return $image_sizes;

  // add all the custom sizes to the built-in sizes
  foreach ( $_wp_additional_image_sizes as $id => $data ) {
    // take the size ID (e.g., 'my-name'), replace hyphens with spaces,
    // and capitalise the first letter of each word
    if ( !isset($image_sizes[$id]) )
      $image_sizes[$id] = ucfirst( str_replace( '-', ' ', $id ) );
    }

  return $image_sizes;
}

function custom_image_setup () {
add_theme_support( 'post-thumbnails' );
add_image_size('175x175', 175, 175, TRUE);
add_image_size('46x46', 46, 46, TRUE);
add_image_size('500w', 500);
add_image_size('800w', 800);
add_image_size('1200w', 1200);
add_image_size('1600w', 1600);
add_image_size('Header 880x496', 880, 496, TRUE);

// To hide these sizes from the admin area, comment out line below
//add_filter( 'image_size_names_choose', 'custom_image_sizes' );
}
add_action( 'after_setup_theme', 'custom_image_setup' );
?>