---
name: "al_set_mixer_postprocess_callback"
section: "3alleg5"
platform: "linux"
package: "allegro5-doc"
version: "2:5.2.10.1+dfsg-1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/al_set_mixer_postprocess_callback/3alleg5"
---

# al\_set\_mixer\_postprocess\_callback(3alleg5)

Allegro 5 API

## NAME

al\_set\_mixer\_postprocess\_callback - Allegro 5 API

## SYNOPSIS

-

  ```
  #include <allegro5/allegro_audio.h>
  bool al_set_mixer_postprocess_callback(ALLEGRO_MIXER *mixer,
     void (*pp_callback)(void *buf, unsigned int samples, void *data),
     void *pp_callback_userdata)
  ```

## DESCRIPTION

Sets a post-processing filter function that’s called after the attached streams have been mixed. The buffer’s format will be whatever the mixer was created with. The sample count and user-data pointer is also passed.

*Note:* The callback is called from a dedicated audio thread.