[MEDIA] Add WebP support

WebP format is now the default image format for anything that
is not an animated GIF. Image Intervention doesn't support
animated WebPs so we don't convert animated GIFs.

ImageFile:
MediaFile:
default:
- Add WebP support

DOCUMENTATION/DEVELOPERS/EVENTS.txt

@@ -1447,7 +1447,7 @@ CreateFileImageThumbnailSource: Hook to create image thumbnail source from a Fil
 
 StartResizeImageFile: Hook to resize an image and output it to a file. No matching End event yet.
 - $imagefile: ImageFile object we're resizing.
-- $outpath:   string with output filepath
+- $outpath:  string with output filepath
 - $box:       array with size ('width', 'height') and boundary box('x', 'y', 'w', 'h').
 
 FillImageFileMetadata: Get more metadata about the ImageFile if it is perhaps not a real local file

lib/media/imagefile.php

@@ -88,12 +88,13 @@ class ImageFile extends MediaFile
             }
             return false;
         };
-        if (!(($cmp($this, IMAGETYPE_GIF)  && function_exists('imagecreatefromgif'))   ||
+        if (!(($cmp($this, IMAGETYPE_GIF)  && function_exists('imagecreatefromgif'))  ||
               ($cmp($this, IMAGETYPE_JPEG) && function_exists('imagecreatefromjpeg')) ||
-              ($cmp($this, IMAGETYPE_BMP)  && function_exists('imagecreatefrombmp'))   ||
+              ($cmp($this, IMAGETYPE_BMP)  && function_exists('imagecreatefrombmp'))  ||
               ($cmp($this, IMAGETYPE_WBMP) && function_exists('imagecreatefromwbmp')) ||
-              ($cmp($this, IMAGETYPE_XBM)  && function_exists('imagecreatefromxbm'))   ||
-              ($cmp($this, IMAGETYPE_PNG)  && function_exists('imagecreatefrompng'))
+              ($cmp($this, IMAGETYPE_XBM)  && function_exists('imagecreatefromxbm'))  ||
+              ($cmp($this, IMAGETYPE_PNG)  && function_exists('imagecreatefrompng'))  ||
+              ($cmp($this, IMAGETYPE_WEBP) && function_exists('imagecreatefromwebp'))
              )
         ) {
             common_debug("Mimetype '{$this->mimetype}' was not recognized as a supported format");
@@ -169,6 +170,7 @@ class ImageFile extends MediaFile
             if ($media !== 'image') {
                 throw new UnsupportedMediaException(_m('Unsupported media format.'), $file->getPath());
             }
+
             if (!empty($file->filename)) {
                 $imgPath = $file->getPath();
             }
@@ -282,22 +284,19 @@ class ImageFile extends MediaFile
     }
 
     /**
-     * Several obscure file types should be normalized to PNG on resize.
+     * Several obscure file types should be normalized to WebP on resize.
      *
-     * Keeps only PNG, JPEG and GIF
+     * Keeps only GIF (if animated) and WebP formats
      *
      * @return int
      */
     public function preferredType()
     {
-        // Keep only JPEG and GIF in their original format
-        if ($this->type === IMAGETYPE_JPEG || $this->type === IMAGETYPE_GIF) {
+        if ($this->type == IMAGETYPE_GIF && $this->animated) {
             return $this->type;
         }
-        // We don't want to save some formats as they are rare, inefficient and antiquated
-        // thus we can't guarantee clients will support
-        // So just save it as PNG
-        return IMAGETYPE_PNG;
+
+        return IMAGETYPE_WEBP;
     }
 
     /**
@@ -436,15 +435,12 @@ class ImageFile extends MediaFile
         // Ensure we save in the correct format and allow customization based on type
         $type = $this->preferredType();
         switch ($type) {
+            case IMAGETYPE_WEBP:
+                $img->save($outpath, 100, 'webp');
+                break;
             case IMAGETYPE_GIF:
                 $img->save($outpath, 100, 'gif');
                 break;
-            case IMAGETYPE_PNG:
-                $img->save($outpath, 100, 'png');
-                break;
-            case IMAGETYPE_JPEG:
-                $img->save($outpath, common_config('image', 'jpegquality'), 'jpg');
-                break;
             default:
                 // TRANS: Exception thrown when trying resize an unknown file type.
                 throw new Exception(_m('Unknown file type'));

lib/media/mediafile.php

@@ -408,8 +408,8 @@ class MediaFile
             if ($media == 'image') {
                 // Use -1 for the id to avoid adding this temporary file to the DB
                 $img = new ImageFile(-1, $_FILES[$param]['tmp_name']);
-                // Validate the image by re-encoding it. Additionally normalizes old formats to PNG,
-                // keeping JPEG and GIF untouched
+                // Validate the image by re-encoding it. Additionally normalizes old formats to WebP,
+                // keeping GIF untouched if animated
                 $outpath = $img->resizeTo($img->filepath);
                 $ext = image_type_to_extension($img->preferredType(), false);
             }

lib/util/default.php

@@ -256,6 +256,7 @@ $default =
                     image_type_to_mime_type(IMAGETYPE_GIF) => image_type_to_extension(IMAGETYPE_GIF),
                     'image/svg+xml' => 'svg', // No built-in constant
                     image_type_to_mime_type(IMAGETYPE_ICO) => image_type_to_extension(IMAGETYPE_ICO),
+                    image_type_to_mime_type(IMAGETYPE_WEBP) => image_type_to_extension(IMAGETYPE_WEBP),
                     'audio/ogg' => 'ogg',
                     'audio/mpeg' => 'mpg',
                     'audio/x-speex' => 'spx',