diff --git a/reference/image/constants.xml b/reference/image/constants.xml
index e2ff7c6a29..fe709c9a03 100644
--- a/reference/image/constants.xml
+++ b/reference/image/constants.xml
@@ -77,6 +77,18 @@
    </listitem>
   </varlistentry>
 
+  <varlistentry xml:id="constant.img-avif">
+   <term>
+    <constant>IMG_AVIF</constant>
+    (<type>int</type>)
+   </term>
+   <listitem>
+    &gd.constants.types;
+    <simpara>
+     Available as of PHP 8.1.0.
+    </simpara>
+   </listitem>
+  </varlistentry>
   <varlistentry xml:id="constant.img-bmp">
    <term>
     <constant>IMG_BMP</constant>
@@ -157,6 +169,17 @@
     </simpara>
    </listitem>
   </varlistentry>
+  <varlistentry xml:id="constant.img-webp-lossless">
+   <term>
+    <constant>IMG_WEBP_LOSSLESS</constant>
+    (<type>int</type>)
+   </term>
+   <listitem>
+    <simpara>
+     Available as of PHP 8.1.0.
+    </simpara>
+   </listitem>
+  </varlistentry>
   <varlistentry xml:id="constant.img-color-tiled">
    <term>
     <constant>IMG_COLOR_TILED</constant> 
diff --git a/reference/image/functions/imagetypes.xml b/reference/image/functions/imagetypes.xml
index 399cd41ef9..705565a59d 100644
--- a/reference/image/functions/imagetypes.xml
+++ b/reference/image/functions/imagetypes.xml
@@ -26,7 +26,7 @@
   <para>
    Returns a bit-field corresponding to the image formats supported by the
    version of GD linked into PHP.  The following bits are returned,
-   <constant>IMG_BMP</constant> |
+   <constant>IMG_AVIF</constant> | <constant>IMG_BMP</constant> |
    <constant>IMG_GIF</constant> | <constant>IMG_JPG</constant> |
    <constant>IMG_PNG</constant> | <constant>IMG_WBMP</constant> | 
    <constant>IMG_XPM</constant> | <constant>IMG_WEBP</constant>.
@@ -45,6 +45,12 @@
       </row>
      </thead>
      <tbody>
+      <row>
+       <entry>8.1.0</entry>
+       <entry>
+        <constant>IMG_AVIF</constant> added.
+       </entry>
+      </row>
       <row>
        <entry>7.2.0</entry>
        <entry>