How to Enable or Disable Dither in FFmpeg

This article explains how to control dithering when resampling audio or changing bit depth using FFmpeg. You will learn the specific command-line options and audio filter parameters required to toggle dithering on or off, helping you manage quantization noise and maintain control over your audio output quality.

Understanding Dithering in FFmpeg

When downsampling audio (for example, converting from 24-bit to 16-bit), quantization error can introduce unwanted distortion. Dithering adds a small amount of randomized noise to mask this distortion.

FFmpeg handles audio resampling via the swresample library. To control whether dithering is applied, you can manipulate two main settings: the dither scale and the dither method.

How to Disable Dithering

The most reliable way to completely disable dithering in FFmpeg is to set the dither scale to 0.

Using Global Command Options

You can apply this globally during a conversion by using the -dither_scale flag:

ffmpeg -i input.wav -c:a pcm_s16le -ar 44100 -dither_scale 0 output.wav

Using the Audio Filtergraph

If you are using the audio resampler filter (aresample), you can pass the dither_scale option directly into the filterchain:

ffmpeg -i input.wav -af "aresample=dither_scale=0" -c:a pcm_s16le output.wav

How to Enable and Configure Dithering

If you want to ensure dithering is active, you must set the dither_scale to 1 (or your preferred intensity) and choose a dither_method.

Available Dither Methods

FFmpeg supports several dithering algorithms: * rectangular * triangular * triangular_hp (High-pass triangular) * lipshitz * shibata * f_weighted * modified_e_weighted * improved_e_weighted

Using Global Command Options

To enable dithering with a specific method (for example, triangular):

ffmpeg -i input.wav -c:a pcm_s16le -dither_method triangular -dither_scale 1 output.wav

Using the Audio Filtergraph

To achieve the same result using the aresample filter:

ffmpeg -i input.wav -af "aresample=dither_method=triangular:dither_scale=1" -c:a pcm_s16le output.wav