a short jingle when a user joins a session, or ringing sound when joining a session. However if you are encountering problems with the AEC not working you should consider adding some sound effects for the AEC to process - e.g. In most scenarios this is not a problem - game sound effects and background music will be enough to keep the AEC synchronised with a suitable delay value. The AEC cannot be calculating the delay value while there is no sound being played and it will slowly "forget" the delay value during long periods of silence. This is achieved automatically but it is important to understand that the AEC system can take several seconds to work out the correct delay value - until it has done this no echo will be cancelled. The most complex part of this system is working out what the delay is between the Audio Postprocessor and the Audio Preprocessor. The AEC filter is attached the the audio mixer on the output, this filter knows what sounds are leaving the speakers and this knowledge can be used to detect and remove that echo in the microphone preprocessor:Īudio Output -> **Audio Postprocessor** -> Speakers -> Echo -> Microphone -> Audio Preprocessor How Does AEC Work? ⚓︎Įcho is caused by sound which leaves the speaker, bounces off some of the nearby environment and re-enters the mic. Acoustic Echo Cancellation (AEC) is a system to automatically remove these echoes from the transmitted voice signal. It can also be very bad on platforms where the mic and the speaker are very close together such as VR headsets and mobile phones. This can be particularly problematic when using Voice Activation Detection (VAD) because the VAD automatically transmits back all speech it detects, causing constant echoes of everything other people say. In a voice session a single person doing this can cause annoying echoes to be transmitted and multiple people doing this simultaneously can cause painful feedback which persists until everyone stops transmitting. When playing audio from speakers and recording audio from a nearby microphone you will often encounter problems when the microphone picks up the audio from the speakers. Error (iOS)Īcoustic Echo Cancellation Acoustic Echo Cancellation ⚓︎
Writing A Custom Microphone Capture Systemįixing Audio effect Dissonance Echo Cancellation could not be found.