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Display Speck 2f dvs
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An example that uses a Speck2fDevKit/Speck2fModuleDevkit to display output spike events of speck2f model in visualizer.

This example bases on packages :

::

    - samna                 0.30.9

Structure:

.. image:: ../../../../images/speck2f_dvs.drawio.png
    :alt: Speck 2f dvs display structure
    :align: center
    :width: 100%

.. code-block:: python

    import samna, samnagui
    import time
    import sys
    import os
    import multiprocessing


    def open_speck2f_dev_kit():
        devices = [
            device
            for device in samna.device.get_unopened_devices()
            if device.device_type_name.startswith("Speck2f")
        ]
        assert devices, "Speck2f board not found"

        # default_config is a optional parameter of open_device
        default_config = samna.speck2fBoards.DevKitDefaultConfig()

        # if nothing is modified on default_config, this invoke is totally same to
        # samna.device.open_device(devices[0])
        return samna.device.open_device(devices[0], default_config)


    def build_samna_event_route(dk, graph, endpoint):
        # build a graph in samna to show dvs
        _, _, streamer = graph.sequential(
            [dk.get_model_source_node(), "Speck2fDvsToVizConverter", "VizEventStreamer"]
        )

        config_source, _ = graph.sequential([samna.BasicSourceNode_ui_event(), streamer])

        streamer.set_streamer_endpoint(endpoint)
        if streamer.wait_for_receiver_count() == 0:
            raise Exception(f'connecting to visualizer on {endpoint} fails')

        return config_source


    def open_visualizer(window_width, window_height, receiver_endpoint):
        # start visualizer in a isolated process which is required on mac, intead of a sub process.
        gui_process = multiprocessing.Process(
            target=samnagui.run_visualizer,
            args=(receiver_endpoint, window_width, window_height),
        )
        gui_process.start()

        return gui_process


    streamer_endpoint = "tcp://0.0.0.0:40000"

    gui_process = open_visualizer(0.75, 0.75, streamer_endpoint)

    dk = open_speck2f_dev_kit()

    # route events
    graph = samna.graph.EventFilterGraph()
    config_source = build_samna_event_route(dk, graph, streamer_endpoint)

    graph.start()

    visualizer_config = samna.ui.VisualizerConfiguration(
        plots=[samna.ui.ActivityPlotConfiguration(128, 128, "DVS Layer", [0, 0, 0.6, 1])]
    )

    config_source.write([visualizer_config])

    # modify configuration
    config = samna.speck2f.configuration.SpeckConfiguration()
    # enable dvs event monitoring
    config.dvs_layer.monitor_enable = True
    dk.get_model().apply_configuration(config)

    # wait until visualizer window destroys.
    gui_process.join()

    graph.stop()