Changeset 54097 for trunk/src/wp-includes/media.php

Timestamp:

09/07/2022 09:43:28 PM (4 years ago)

Author:

flixos90

Message:

Media: Generate WebP only for certain registered image sizes.

The existing filter image_editor_output_format receives an additional parameter $size_name which is populated whenever it controls the output format for a specific registered image size to create. Otherwise, it remains empty. In order to achieve this, a low level change has been added in bringing a new $size_name class property to the WP_Image_Editor base class, which is introduced in a backward compatible way that will not cause conflicts with custom implementations.

This parameter is then used in new logic inside the wp_default_image_output_mapping() callback function for the filter, controlling whether image/jpeg should map to image/webp output or not. By default, this is enabled for all WordPress core image sizes by default, and this list can be modified using a new wp_image_sizes_with_additional_mime_type_support filter, e.g. to remove core sizes or add custom sizes.

The customization per image size may be further enhanced by providing a more declarative API via a new parameter on the add_image_size() function.

Props eugenemanuilov, flixos90, adamsilverstein, joegrainger.

Fixes #56526.
See #55443, #56288.

File:

• trunk/src/wp-includes/media.php (modified) (1 diff)

trunk/src/wp-includes/media.php

@@ -3913 +3913 @@
  *
  * @param array $output_mapping Map of mime type to output format.
- * @retun array The adjusted default output mapping.
- */
-function wp_default_image_output_mapping( $output_mapping ) {
+ * @param string $filename  Path to the image.
+ * @param string $mime_type The source image mime type.
+ * @param string $size_name Optional. The image size name to create, or empty string if not set. Default empty string.
+ * @return array The adjusted default output mapping.
+ */
+function wp_default_image_output_mapping( $output_mapping, $filename, $mime_type, $size_name = '' ) {
+    // If size name is specified, check whether the size supports additional MIME types like WebP.
+    if ( $size_name ) {
+        // Include only the core sizes that do not rely on add_image_size(). Additional image sizes are opt-in.
+        $enabled_sizes = array(
+            'thumbnail'      => true,
+            'medium'         => true,
+            'medium_large'   => true,
+            'large'          => true,
+            'post-thumbnail' => true,
+        );
+
+        /**
+         * Filters the sizes that support secondary mime type output. Developers can use this
+         * to control the generation of additional mime type sub-sized images.
+         *
+         * @since 6.1.0
+         *
+         * @param array $enabled_sizes Map of size names and whether they support secondary mime type output.
+         */
+        $enabled_sizes = apply_filters( 'wp_image_sizes_with_additional_mime_type_support', $enabled_sizes );
+
+        // Bail early if the size does not support additional MIME types.
+        if ( empty( $enabled_sizes[ $size_name ] ) ) {
+            return $output_mapping;
+        }
+    }
+
     $output_mapping['image/jpeg'] = 'image/webp';
     return $output_mapping;