Source (purple) elements are the audio and data inputs. Every PIPE requires an input to work.
| List of Source Elements | Description |
| Audio | Analog or digital audio input |
| Audio over IP |
Audio over IP input
|
| DTMF | DTMF tone generation |
| Data |
Encapsulated audio or non-audio data
|
| Demux |
Demux input
|
| File | File playback |
| Monitor | Monitoring multiple inputs |
| RTP | RTP stream input |
| Reference | Reusing sources of other PIPEs |
| SRT | SRT stream input |
| Test | Test signal playback |
| URL | Restream of web stream |
| WebRTC | WebRTC stream input |