Add Oboe 1.4.3, used only for Android build.

2026-08-18 03:34:25 +02:00 · 2021-02-12 19:55:07 +08:00
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+[Tech Notes Home](README.md)
+
+# Using Audio Effects with Oboe
+
+## Overview
+
+The Android Audio framework provides some effects processing that can be used by apps.
+It is available through the Java or Kotlin
+[AudioEffect API](https://developer.android.com/reference/android/media/audiofx/AudioEffect)
+
+Another alternative is to do your own effects processing in your own app.
+
+### Reasons to use the Android AudioEffect in the OS:
+1. Functions are provided for you so they are easy to use.
+
+### Reasons to do your own effects Processing:
+1. They will work on all versions of Android. The AudioEffects can only be used with Oboe on Android 9 (Pie) and above. They are not supported for OpenSL ES.
+2. You can customize the effects as needed.
+3. You can get lower latency when you use your own effects. Using Android AudioEffects prevents you from getting a low latency path.
+
+## Using Android AudioEffects
+
+Oboe streams on Android 9 (Pie) and above can use the Java/Kotlin.
+See [AudioEffect API](https://developer.android.com/reference/android/media/audiofx/AudioEffect)
+
+The basic idea is to use Java or Kotlin to create a Session with Effects. 
+Then associate your Oboe streams with the session by creating them with a SessionID.
+
+In Java:
+
+    AudioManager audioManager = (AudioManager) context.getSystemService(Context.AUDIO_SERVICE);
+    int audioSessionId = audioManager.generateAudioSessionId();
+    
+Pass the audioSessionId to your C++ code using JNI. Then use it when opening your Oboe streams:
+
+    builder->setSessionId(sessionId);
+
+Note that these streams will probably not have low latency. So you may want to do your own effects processing.
+
+## Using Third Party Affects Processing
+
+There are many options for finding audio effects.
+
+- [Music DSP Archive](http://www.musicdsp.org/en/latest/Effects/index.html)
+- [Synthesis Toolkit in C++ (STK)](https://ccrma.stanford.edu/software/stk/index.html)
+- [Cookbook for Biquad Filters, EQ, etc.](https://www.w3.org/2011/audio/audio-eq-cookbook.html)
+- [Faust - language for generating effects, big library](https://faust.grame.fr/index.html)
+- [DAFX Digital Audio Effects conference proceedings](http://dafx.de/)