Big delay on custom gstreamer app

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1

Hi,

We are developing a custom application for the Herelink RC. So far we are able to get the stream using a native plugin in Android (java) that we’ve developed. Our plugin connects to rtsp://192.168.0.10:8554/H264Video (according to this post ) and even though we can view the stream, it has 3-4 second delay which does not happen when running the updated QGC app.

We have also tried playing the stream using one of gstreamer’s examples for android:
https://gitlab.freedesktop.org/gstreamer/gst-docs/-/tree/master/examples/tutorials/android/android-tutorial-4
Using gstreamer 1.18.5 and replacing the url in the playbin by rtsp://192.168.0.10:8554/H264Video. However, the 3-4 second delay also happens here.

Any hints on why this is happening or alternatives that allow us to replicate QGC’s stream in our custom app are greatly apreciated.

Thanks.

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whats your pipeline?

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Hi @Michael_Oborne,

In the meantime we found a solution. The pipeline we were using was the one from tutorial 4 in gst-docs/examples/tutorials/android, which is just a regular playbin.

Forcing the latency property to a low value, such as 100, fixed the lag issue:

data->pipeline = gst_parse_launch ("playbin uridecodebin0::source::latency=100", &error);