Gstreamer Pipeline for RTP (PCMU coded) UDP Src to File Write
This article will cover the creation of a Gstreamer pipeline that reads RTP (PCMU coded) UDP packets and writes them to a file. The pipeline works fine as demonstrated by the command:
gst-launch-1.0 -e udpsrc port=9998 caps="application/x-rtp, media=(string)audio, (int)RTP_Payloader=9, (int)encoding-name=(string)PCMU" ! rtpjitterbuffer latency=500 ! audioresample ! audio/x-raw-alaw ! filesink location=output.raw
Pipeline Explanation
The pipeline consists of the following elements:
- udpsrc: This source element receives RTP packets from a UDP socket. The port number is set to 9998.
- rtpjitterbuffer: This element is used to reduce the jitter in the RTP packets. The latency is set to 500 microseconds.
- audioresample: This element resamples the audio data if necessary to match the desired output format.
- audio/x-raw-alaw: This element decodes the ALaw (G.711 u-law) encoded audio data.
- filesink: This sink element writes the decoded audio data to a file named "output.raw".
References
- Books: GStreamer Developer's Reference Guide
- Articles: GStreamer RTP Tutorial
- Online Resources: GStreamer Documentation