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do_action( "hook_name" )apply_filters( "hook_name", "what_to_filter" ).Remember, this hook may occur in more than one file. Moreover, the hook's context may change from version to version.
This hook occurs 2 times in this file.
| Line | Code | 
|---|---|
| 139 |           return false; | 
| 140 |  | 
| 141 |      $img_url = wp_get_attachment_url($id); | 
| 142 |      $meta = wp_get_attachment_metadata($id); | 
| 143 |      $width = $height = 0; | 
| 144 |      $is_intermediate = false; | 
| 145 |      $img_url_basename = wp_basename($img_url); | 
| 146 |  | 
| 147 |      // plugins can use this to provide resize services | 
| 148 |      if ( $out = apply_filters('image_downsize', false, $id, $size) ) | 
| 149 |           return $out; | 
| 150 |  | 
| 151 |      // try for a new style intermediate size | 
| 152 |      if ( $intermediate = image_get_intermediate_size($id, $size) ) { | 
| 153 |           $img_url = str_replace($img_url_basename, $intermediate['file'], $img_url); | 
| 154 |           $width = $intermediate['width']; | 
| 155 |           $height = $intermediate['height']; | 
| 156 |           $is_intermediate = true; | 
| 157 |      } | 
| Line | Code | 
| 1368 |                'full'      => __('Full Size'), | 
| 1369 |           ) ); | 
| 1370 |           unset( $possible_sizes['full'] ); | 
| 1371 |  | 
| 1372 |           // Loop through all potential sizes that may be chosen. Try to do this with some efficiency. | 
| 1373 |           // First: run the image_downsize filter. If it returns something, we can use its data. | 
| 1374 |           // If the filter does not return something, then image_downsize() is just an expensive | 
| 1375 |           // way to check the image metadata, which we do second. | 
| 1376 |           foreach ( $possible_sizes as $size => $label ) { | 
| 1377 |                if ( $downsize = apply_filters( 'image_downsize', false, $attachment->ID, $size ) ) { | 
| 1378 |                     if ( ! $downsize[3] ) | 
| 1379 |                          continue; | 
| 1380 |                     $sizes[ $size ] = array( | 
| 1381 |                          'height'      => $downsize[2], | 
| 1382 |                          'width'       => $downsize[1], | 
| 1383 |                          'url'         => $downsize[0], | 
| 1384 |                          'orientation' => $downsize[2] > $downsize[1] ? 'portrait' : 'landscape', | 
| 1385 |                     ); | 
| 1386 |                } elseif ( isset( $meta['sizes'][ $size ] ) ) { |