adjust load vips

lib/image_utils.rb

@@ -1,23 +1,33 @@
 # frozen_string_literal: true
 
 module ImageUtils
+  PNG_REGEXP = %r{\Aimage/(?:png|apng|vnd\.mozilla\.apng)\z}
+  JPEG_REGEXP = %r{\Aimage/(?:jpeg|jpg|pjpeg)\z}
   ICO_REGEXP = %r{\Aimage/(?:x-icon|vnd\.microsoft\.icon)\z}
   BMP_REGEXP = %r{\Aimage/(?:bmp|x-bmp|x-ms-bmp)\z}
 
+  UnsupportedFormat = Class.new(StandardError)
+
   module_function
 
   def load_vips(data, content_type: nil, autorot: false)
     content_type ||= Marcel::MimeType.for(data)
 
-    if ICO_REGEXP.match?(content_type)
-      LoadIco.call(data)
-    elsif BMP_REGEXP.match?(content_type)
-      LoadBmp.call(data)
-    else
-      image = Vips::Image.new_from_buffer(data, '')
+    image =
+      case content_type
+      when PNG_REGEXP
+        Vips::Image.pngload_buffer(data)
+      when JPEG_REGEXP
+        Vips::Image.jpegload_buffer(data)
+      when ICO_REGEXP
+        LoadIco.call(data)
+      when BMP_REGEXP
+        LoadBmp.call(data)
+      else
+        raise UnsupportedFormat, content_type.to_s
+      end
 
-      autorot ? image.autorot : image
-    end
+    autorot ? image.autorot : image
   end
 
   def blank?(image)