I've got an app that records audio. I'm wondering how I can increase the gain. is there a way to normalize the audio or amplify it somehow?
thanks, howie
Looks like I found a solution. According to the documentation the AVAudioPlayer volume can be between 0.0 and 1.0. Apparently it can be set to a value greater than 1.0. By increasing the volume I was able to achieve the same desired result. While it's not normalized, the gain is increased.
#import <AudioToolbox/AudioServices.h>
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,
sizeof (audioRouteOverride),&audioRouteOverride);
It will play your sound in Speaker mode.
来源:https://stackoverflow.com/questions/2893636/avaudiorecorder-normalize-volume