diff --git a/lang/en/mimetypes.php b/lang/en/mimetypes.php
index cbcd32914fc..83f4257b334 100644
--- a/lang/en/mimetypes.php
+++ b/lang/en/mimetypes.php
@@ -74,6 +74,7 @@ $string['group:html_track'] = 'HTML track files';
 $string['group:html_video'] = 'Video files natively supported by browsers';
 $string['group:image'] = 'Image files';
 $string['group:media_source'] = 'Streaming media';
+$string['group:optimised_image'] = 'Image files to be optimised, such as badges';
 $string['group:presentation'] = 'Presentation files';
 $string['group:sourcecode'] = 'Source code';
 $string['group:spreadsheet'] = 'Spreadsheet files';
diff --git a/lib/classes/filetypes.php b/lib/classes/filetypes.php
index e1e04168b9e..8d32b35c9d3 100644
--- a/lib/classes/filetypes.php
+++ b/lib/classes/filetypes.php
@@ -107,7 +107,8 @@ abstract class core_filetypes {
                     'groups' => array('spreadsheet')),
             'gslides' => array('type' => 'application/vnd.google-apps.presentation', 'icon' => 'powerpoint',
                     'groups' => array('presentation')),
-            'gif' => array('type' => 'image/gif', 'icon' => 'gif', 'groups' => array('image', 'web_image'), 'string' => 'image'),
+            'gif' => array('type' => 'image/gif', 'icon' => 'gif', 'groups' => array('image', 'web_image', 'optimised_image'),
+                'string' => 'image'),
             'gtar' => array('type' => 'application/x-gtar', 'icon' => 'archive',
                     'groups' => array('archive'), 'string' => 'archive'),
             'tgz' => array('type' => 'application/g-zip', 'icon' => 'archive', 'groups' => array('archive'), 'string' => 'archive'),
@@ -136,9 +137,12 @@ abstract class core_filetypes {
             'jmt' => array('type' => 'text/xml', 'icon' => 'markup'),
             'jmx' => array('type' => 'text/xml', 'icon' => 'markup'),
             'jnlp' => array('type' => 'application/x-java-jnlp-file', 'icon' => 'markup'),
-            'jpe' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image'), 'string' => 'image'),
-            'jpeg' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image'), 'string' => 'image'),
-            'jpg' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image'), 'string' => 'image'),
+            'jpe' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image', 'optimised_image'),
+                'string' => 'image'),
+            'jpeg' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image', 'optimised_image'),
+                'string' => 'image'),
+            'jpg' => array('type' => 'image/jpeg', 'icon' => 'jpeg', 'groups' => array('image', 'web_image', 'optimised_image'),
+                'string' => 'image'),
             'jqz' => array('type' => 'text/xml', 'icon' => 'markup'),
             'js' => array('type' => 'application/x-javascript', 'icon' => 'text', 'groups' => array('web_file')),
             'json' => array('type' => 'application/json', 'icon' => 'text'),
@@ -206,7 +210,8 @@ abstract class core_filetypes {
             'php' => array('type' => 'text/plain', 'icon' => 'sourcecode'),
             'pic' => array('type' => 'image/pict', 'icon' => 'image', 'groups' => array('image'), 'string' => 'image'),
             'pict' => array('type' => 'image/pict', 'icon' => 'image', 'groups' => array('image'), 'string' => 'image'),
-            'png' => array('type' => 'image/png', 'icon' => 'png', 'groups' => array('image', 'web_image'), 'string' => 'image'),
+            'png' => array('type' => 'image/png', 'icon' => 'png', 'groups' => array('image', 'web_image', 'optimised_image'),
+                'string' => 'image'),
             'pps' => array('type' => 'application/vnd.ms-powerpoint', 'icon' => 'powerpoint', 'groups' => array('presentation')),
             'ppt' => array('type' => 'application/vnd.ms-powerpoint', 'icon' => 'powerpoint', 'groups' => array('presentation')),
             'pptx' => array('type' => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
diff --git a/lib/filelib.php b/lib/filelib.php
index 2a42f8e9ace..fd0c43e4afd 100644
--- a/lib/filelib.php
+++ b/lib/filelib.php
@@ -1639,6 +1639,7 @@ function download_file_content($url, $headers=null, $postdata=null, $fullrespons
  *     commonly used in moodle the following groups:
  *       - web_image - image that can be included as <img> in HTML
  *       - image - image that we can parse using GD to find it's dimensions, also used for portfolio format
+ *       - optimised_image - image that will be processed and optimised
  *       - video - file that can be imported as video in text editor
  *       - audio - file that can be imported as audio in text editor
  *       - archive - we can extract files from this archive
diff --git a/lib/form/tests/filetypes_util_test.php b/lib/form/tests/filetypes_util_test.php
index 7fb1b5f95b0..355fefe4e7b 100644
--- a/lib/form/tests/filetypes_util_test.php
+++ b/lib/form/tests/filetypes_util_test.php
@@ -302,10 +302,10 @@ class filetypes_util_testcase extends advanced_testcase {
         // All these three files are in both "image" and also "web_image"
         // groups. We display both groups.
         $data = $util->data_for_browser('jpg png gif', true, '.gif');
-        $this->assertEquals(2, count($data));
+        $this->assertEquals(3, count($data));
         $this->assertTrue($data[0]->key !== $data[1]->key);
         foreach ($data as $group) {
-            $this->assertTrue(($group->key === 'image' || $group->key === 'web_image'));
+            $this->assertTrue(($group->key === 'image' || $group->key === 'web_image' || $group->key === 'optimised_image'));
             $this->assertEquals(3, count($group->types));
             $this->assertFalse($group->selectable);
             foreach ($group->types as $ext) {
@@ -317,11 +317,11 @@ class filetypes_util_testcase extends advanced_testcase {
             }
         }
 
-        // There is a group web_image which is a subset of the group image. The
-        // file extensions that fall into both groups will be displayed twice.
+        // The groups web_image and optimised_image are a subset of the group image. The
+        // file extensions that fall into these groups will be displayed thrice.
         $data = $util->data_for_browser('web_image');
         foreach ($data as $group) {
-            $this->assertTrue(($group->key === 'image' || $group->key === 'web_image'));
+            $this->assertTrue(($group->key === 'image' || $group->key === 'web_image' || $group->key === 'optimised_image'));
         }
 
         // Check that "All file types" are displayed first.