Hi all, i want to transmitt a video stream with gnuradio and usrps. There are some examples on the web and i got it working with vlc.
The problem is, that the playback is quite choppey. This is because the digital transmission over the usrps has a fixed rate but the encoded video has a variable rate. If i set the transmission rate higher than the (mean) rate of the video, i get a lot of underruns on the tranmitting usrp (= chopped of rf signal). Which is bad because the transmission designed to be continous (for example the clockloop, ...). The transmission is based on fixed size fec code blocks starting with an preambel. A possible solution could be to stuff zeros between two blocks while waiting on the (video) source. On the receiver this stuffed zeros would be trown away automatically. That "zero stuffing" could be realized with a block, that puts out N (N= payload size of one block) input samples (first sample marked with a tag) at one "piece" or (if it has no N input samples in some internal buffer) it puts out zeros). Based on the tag a downstream block could mux in the preambel and everything would be fine. But here is my question: I don´t know how to write a block, that always has output samples available. Is there i kind of a non-blocking block template? Best regards, *Anselm*
_______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
