path: root/voctocore/experiments/shmsrc.py

#!/usr/bin/python3
from gi.repository import GObject, Gst

class ShmSrc(Gst.Bin):
    def __init__(self, socket, caps):
        super().__init__()

        # Create elements
        self.shmsrc = Gst.ElementFactory.make('shmsrc', None)
        self.caps = Gst.ElementFactory.make('capsfilter', None)

        # Add elements to Bin
        self.add(self.shmsrc)
        self.add(self.caps)

        # Set properties
        self.shmsrc.set_property('socket-path', socket)
        self.shmsrc.set_property('is-live', True)
        self.shmsrc.set_property('do-timestamp', True)

        self.caps.set_property('caps', caps)
        self.shmsrc.link(self.caps)
        self.shmsrc.get_static_pad('src').add_probe(Gst.PadProbeType.BLOCK | Gst.PadProbeType.EVENT_DOWNSTREAM, self.event_probe, None)
        self.shmsrc.get_static_pad('src').add_probe(Gst.PadProbeType.IDLE | Gst.PadProbeType.DATA_DOWNSTREAM, self.data_probe, None)

        # Add Ghost Pads
        self.add_pad(
            Gst.GhostPad.new('sink', self.caps.get_static_pad('src'))
        )

    def event_probe(self, pad, info, ud):
        e = info.get_event()
        print("event_probe", e.type)
        if e.type == Gst.EventType.EOS:
            print("shmsrc reported EOS - switching to failover")
            return Gst.PadProbeReturn.DROP
        return Gst.PadProbeReturn.PASS

    def data_probe(self, pad, info, ud):
        print("shmsrc sends data - switching to shmsrc")
        return Gst.PadProbeReturn.PASS