Stop CoreAudio from doing expensive audio rate conversion

libsdl-org · Feb 23, 2017 · 71a4e8e · 71a4e8e
1 parent a976255
commit 71a4e8e
Showing 1 changed file with 7 additions and 0 deletions.
diff --git a/src/audio/coreaudio/SDL_coreaudio.m b/src/audio/coreaudio/SDL_coreaudio.m
@@ -734,6 +734,13 @@ static BOOL update_audio_session(_THIS, SDL_bool open)
     if (!update_audio_session(this, SDL_TRUE)) {
         return -1;
     }
+
+    /* Stop CoreAudio from doing expensive audio rate conversion */
+    @autoreleasepool {
+        AVAudioSession* session = [AVAudioSession sharedInstance];
+        [session setPreferredSampleRate:this->spec.freq error:nil];
+        this->spec.freq = (int)session.sampleRate;
+    }
 #endif
 
     /* Setup a AudioStreamBasicDescription with the requested format */