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videoh.264gstreamergnuradiousrp

How to send a video file with GNURadio and USRP's?

I am trying to send a video file using GNURadio,GRC and USRP1's with a RFX2400 and a 2.4GHZ antenna using a .ts video file. We have two USRP's, one working as the transmitter and the other as the receiver. We are using GMSK modulation and demodulation with the encoding and decoding done before and after the modulation and demod is done, as well as the constant multiplying before sending the signal from one USRP to the other. Low pass filtering is done to the received signal before demodulating it and decoding it, this is then saved to a video_output.ts file.

Here is where we have our current problem. We have a video that we made ourselves. When we send this video across our output video file never contains information even though we can see because of an FFT sink placed in between the LPF and the USRP source that something is being received on the USRP. How can I make it so that I actually save those bytes that are coming in.

We read that we are going to have to create two piping files using mkfifo command and then copying the video file we want to transmit to the piping file created and then we should be able to send a file properly. This is then giving me some extra problems. Ive been installing packages that would include x264 and h264 encoding in any way but still gives the error that no type of encoding found. We did make install to the x264 package and still wouldnt work. So atm we are stuck in trying to encode our video file to the piping file created.

Thanks,

Solution

  • I will suggest you to start with more easy applications and when you sure that this step is ok, proceed to the next.

    For example at the beginning forget the USRPs. Use the File source blocks and try to send a file containing in each line an increasing counter or whatever you want doesn't matter. Pass it through your modulation scheme and at the same flow graph demodulate and save it with a file sink block. Now check if the two files are the same.

    If yes do the same examle, but now using the usrps and transmitting over the air. If also this succeeds, you can then start playing with video transmission.

    Note that you should play also at the simulation phase, by adding some noise to see how your systems reacts because possibly your environment at the 2.4GHZ may be noisy.