diff --git a/reference/image/functions/imageftbbox.xml b/reference/image/functions/imageftbbox.xml
index 2662419872..289d5c836b 100644
--- a/reference/image/functions/imageftbbox.xml
+++ b/reference/image/functions/imageftbbox.xml
@@ -19,6 +19,13 @@
    This function calculates and returns the bounding box in pixels
    for a FreeType text.
   </para>
+  <note>
+   <para>
+    <function>imageftbbox</function> is an extended variant of
+    <function>imagettfbbox</function> which additionally supports the
+    <parameter>extrainfo</parameter>.
+   </para>
+  </note>
  </refsect1>
  <refsect1 role="parameters">
   &reftitle.parameters;
diff --git a/reference/image/functions/imagefttext.xml b/reference/image/functions/imagefttext.xml
index c0c037466c..f2b7cae03b 100644
--- a/reference/image/functions/imagefttext.xml
+++ b/reference/image/functions/imagefttext.xml
@@ -19,6 +19,13 @@
    <methodparam><type>string</type><parameter>text</parameter></methodparam>
    <methodparam choice="opt"><type>array</type><parameter>extrainfo</parameter></methodparam>
   </methodsynopsis>
+  <note>
+   <para>
+    <function>imagefttext</function> is an extended variant of
+    <function>imagettftext</function> which additionally supports the
+    <parameter>extrainfo</parameter>.
+   </para>
+  </note>
  </refsect1>
  <refsect1 role="parameters">
   &reftitle.parameters;
diff --git a/reference/image/functions/imagettfbbox.xml b/reference/image/functions/imagettfbbox.xml
index a8af89e068..74036e74e8 100644
--- a/reference/image/functions/imagettfbbox.xml
+++ b/reference/image/functions/imagettfbbox.xml
@@ -18,6 +18,13 @@
    This function calculates and returns the bounding box in pixels
    for a TrueType text.
   </para>
+  <note>
+   <para>
+    <function>imageftbbox</function> is an extended variant of
+    <function>imagettfbbox</function> which additionally supports the
+    <parameter>extrainfo</parameter>.
+   </para>
+  </note>
  </refsect1>
  <refsect1 role="parameters">
   &reftitle.parameters;
diff --git a/reference/image/functions/imagettftext.xml b/reference/image/functions/imagettftext.xml
index 876d38a19a..ab27268ac1 100644
--- a/reference/image/functions/imagettftext.xml
+++ b/reference/image/functions/imagettftext.xml
@@ -22,6 +22,13 @@
    Writes the given <parameter>text</parameter> into the image using TrueType
    fonts.
   </para>
+  <note>
+   <para>
+    <function>imagefttext</function> is an extended variant of
+    <function>imagettftext</function> which additionally supports the
+    <parameter>extrainfo</parameter>.
+   </para>
+  </note>
  </refsect1>
  <refsect1 role="parameters">
   &reftitle.parameters;