Multi-channel identification in the python

[vtpl1]

Hi,
How to identify each channel uniquely in pad probe callback in python for multi channel pipeline?

[mliu2020]

Hi @vtpl1
Sorry for the late response, I think you can figure out from the message object, it has a "src" field.
You can check MessageType in call back and check the channel info.
https://gstreamer.freedesktop.org/documentation/gstreamer/gstmessage.html?gi-language=python#GstMessageType
Mark

[mikhail-nikolskiy]

@vtpl1,

You will need to assign different (unique) name in each channel, ex

channel#1: ... ! gvawatermark name=gvawatermark1 ! ...
channel#2: ... ! gvawatermark name=gvawatermark2 ! ...

then you can set callback for each channel (in the loop)

    pad = pipeline.get_by_name("gvawatermark1").get_static_pad("src")
    pad.add_probe(Gst.PadProbeType.BUFFER, pad_probe_callback)

    pad = pipeline.get_by_name("gvawatermark2").get_static_pad("src")
    pad.add_probe(Gst.PadProbeType.BUFFER, pad_probe_callback)