# Audio Codecs

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## OPUS

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The OPUS codec is supported when streaming in RTSP(S), SRT, and Multicast UDP protocols. If you will be viewing the 
stream in a web browser via WebRTC, use this codec for the best quality.

## AAC

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AAC is supported in all streaming protocols. If you will be viewing the stream in a web browser make sure to view it via
HLS. HLS supports AAC audio while WebRTC does not.

## G711

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The G711 codec is locked to a sample rate of 8000hz and mono audio. Both RTSP(S) and RTMP(S) support G711 while SRT does not.

## Compatibility Matrix

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|               | OPUS | AAC | G711 |
|---------------|------|-----|------|
| RTSP(S)       | Yes  | Yes | Yes  |
| RTMP(S)       | No   | Yes | Yes  |
| SRT           | Yes  | Yes | No   |
| Multicast UDP | Yes  | Yes | No   |