How to Change Video Speed without Changing Pitch in mpv?

Adjusting video playback speed without distorting the audio pitch is a crucial feature for watching lectures, tutorials, or movies efficiently. In the mpv media player, this functionality is built-in and enabled by default through an audio filter called scaletempo. This article covers the default keyboard shortcuts for altering speed, how to ensure pitch correction is active, and how to customize your configuration settings for a seamless viewing experience.

Default Keyboard Shortcuts for Speed Adjustment

The simplest way to change playback speed in mpv is by using the default hotkeys during playback. These keys adjust the speed in increments of 10% or double/halve it instantly.

Ensuring Pitch Correction is Enabled

By default, mpv keeps the audio pitch intact when changing speed because the audio-pitch-correction setting is turned on. If you notice the audio sounding like a “chipmunk” when speeding up or becoming deeply distorted when slowing down, the setting may have been accidentally disabled.

To force pitch correction via the command line, you can launch mpv with the following flag:

mpv --audio-pitch-correction=yes video.mp4

Automating the Setting in your Configuration File

If you want to ensure that pitch correction is permanently enabled without typing a command line flag every time, you can add it to your mpv configuration file (mpv.conf).

  1. Locate or create your mpv.conf file:
  1. Open the file in a text editor and add the following line:
audio-pitch-correction=yes

Customizing Speed Increments

If the default 10% change feels too drastic or too slow, you can customize the exact speed adjustment steps by editing your input.conf file (located in the same folder as mpv.conf).

For example, to change the speed by 5% increments using the same brackets, add these lines to input.conf:

] multiply speed 1.05
[ multiply speed 0.95