diff --git a/rtfd/public/ffmpeg/snippets.rst b/rtfd/public/ffmpeg/snippets.rst
index 7605620..9514416 100644
--- a/rtfd/public/ffmpeg/snippets.rst
+++ b/rtfd/public/ffmpeg/snippets.rst
@@ -93,3 +93,15 @@ Closest I frames
  -to 00:00:02.000 \
  -codec copy \
  -y output.mkv
+
+Change speed
+============
+
+.. code:: shell
+
+ -r 120 \
+ -filter:v "setpts=0.5*PTS"
+
+.. code:: shell
+
+ -filter:a "atempo=2.0"