From f9e82708ba2981466daa70347d9f8378801c532a Mon Sep 17 00:00:00 2001
From: tsnorri <tsnorri@iki.fi>
Date: Thu, 31 May 2018 16:42:45 +0300
Subject: [PATCH 1/2] Add a method for freeing the image file, free each
 derivative after it has been created

---
 system/src/Grav/Common/Page/Medium/ImageMedium.php | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/system/src/Grav/Common/Page/Medium/ImageMedium.php b/system/src/Grav/Common/Page/Medium/ImageMedium.php
index 05bc4c486c..beab621d20 100644
--- a/system/src/Grav/Common/Page/Medium/ImageMedium.php
+++ b/system/src/Grav/Common/Page/Medium/ImageMedium.php
@@ -301,6 +301,7 @@ public function derivatives($min_width, $max_width = 2500, $step = 200) {
                 $derivative->set('width', $width);
                 $derivative->set('height', $height);
 
+                $derivative->resetImage();
                 $this->addAlternative($ratio, $derivative);
             }
         }
@@ -558,6 +559,14 @@ protected function image()
 
         return $this;
     }
+    
+    /**
+     * Frees the cached image file.
+     */
+    protected function resetImage()
+    {
+        $this->image = null;
+    }
 
     /**
      * Save the image with cache.

From 9050e3b0e22e490fd24cf48fa8c84aadba5207c5 Mon Sep 17 00:00:00 2001
From: tsnorri <tsnorri@iki.fi>
Date: Thu, 31 May 2018 17:46:40 +0300
Subject: [PATCH 2/2] Save the scaled derivative on disk before freeing it,
 store its path

---
 system/src/Grav/Common/Page/Medium/ImageMedium.php | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/system/src/Grav/Common/Page/Medium/ImageMedium.php b/system/src/Grav/Common/Page/Medium/ImageMedium.php
index beab621d20..8be914e12c 100644
--- a/system/src/Grav/Common/Page/Medium/ImageMedium.php
+++ b/system/src/Grav/Common/Page/Medium/ImageMedium.php
@@ -301,6 +301,7 @@ public function derivatives($min_width, $max_width = 2500, $step = 200) {
                 $derivative->set('width', $width);
                 $derivative->set('height', $height);
 
+                $derivative->saveImage();
                 $derivative->resetImage();
                 $this->addAlternative($ratio, $derivative);
             }
@@ -559,7 +560,7 @@ protected function image()
 
         return $this;
     }
-    
+
     /**
      * Frees the cached image file.
      */
@@ -596,7 +597,9 @@ protected function saveImage()
             $this->image->merge(ImageFile::open($overlay));
         }
 
-        return $this->image->cacheFile($this->format, $this->quality);
+        $cachedPath = $this->image->cacheFile($this->format, $this->quality);
+        $this->set('filepath', $cachedPath);
+        return $cachedPath;
     }
 
     /**