Difference between revisions of "Simple DVB with Gstreamer and GNU Radio"

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(Conceptual prototype (DVB Mk0))
(Conceptual prototype (DVB Mk0))
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=== Transmitter ===
 
=== Transmitter ===
  
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[[Image:GmskTx.jpg|600px]]
  
 
=== Receiver ===
 
=== Receiver ===

Revision as of 21:55, 7 August 2010

This article describes a simple video broadcasting setup based on Gstreamer, GNU Radio and the Universal Software Radio Peripheral (USRP).

DvbSys.jpg


Overview

Conceptual prototype (DVB Mk0)

This is the very first muck-up that I used to get my Logitech Webcam Pro 9000 webcam on the air. Gstreamer and GNU Radio are connected using a named pipe.

DvbSysDia.png


Transmitter

GmskTx.jpg

Receiver

Transceiver

This simple, full duplex transceiver was created to allow using one computer and one USRP for both transmit and receive. By default, both the receiver and the transmitter are set to use the same frequency so that the receiver will receive what the local transmitter transmits; however, it can also be used to make two way video contacts.

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This transceiver has been running well on a 13" 2.4GHz MacBook Pro for more than 4.5 hours (video of the setup).

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Simulator

This simple simulator was used to test the idea before it was put on the air. It simply sends the video through a GMS modulator, mixes it with noise, the a GMSK demodulator.

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A video demo of the simulator in action is available here.

Problems / TODOs

  • The MPEG-TS muxer in Gstreamer does not currently support CBR and the only way to get close to CBR is via the H.264 encoder, which is not constant enough.
    • Fix the MPEG-TS muxer
    • The MPEG-TS muxer in the mplayer repository has been updated to support CBR


References

Blogs

Videos

  • 2010.07.25: GStreamer / GNU Radio video transmission simulator - first signals: YouTube.
  • 2010.08.03: DVB with GNU Radio and Gstreamer - Test stream: YouTube.
  • 2010.08.03: DVB with GNU Radio and Gstreamer - Webcam: YouTube.
  • 2010.08.07: DVB with GNU Radio and GStreamer - GMSK Transceiver: YouTube.

Related articles

  1. Embedded Video Processing and Radio Unit