Arducam imx477 4k@30fps with jetson nano

Robotics & Edge Computing Jetson & Embedded Systems Jetson Nano
, , ,
9

On the topic of getting the image buffer from gstreamer in python.

try this:

import gi
gi.require_version(‘Gst’, ‘1.0’)
gi.require_version(‘GstVideo’, ‘1.0’)
gi.require_version(‘GstBase’, ‘1.0’)

from gi.repository import GLib, GObject, Gst, GstBase, GstVideo

Gst.init(None)

then define the pipeline

pipeline = ('nvarguscamerasrc name=src_camera sensor_id=%d ! ’
'video/x-raw(memory:NVMM), width=(int)%d, height=(int)%d, framerate=(fraction)%d/1 ! ’
'nvvidconv output-buffers=1 ! ’
'video/x-raw, ’
'format=(string)BGRx ! videoconvert ! video/x-raw, ’
‘format=(string)BGR ! appsink max-buffers=1 drop=true name=appsink emit-signals=True’ %(camera_number, frame_width, frame_height, frame_rate))

then set up the pipeline:

gst_pipeline = Gst.parse_launch(pipeline)

Define the callback function:

def on_new_sample(sink):

        sample = sink.emit('pull-sample')             
        buffer = sample.get_buffer()

        caps = sample.get_caps()
        height = caps.get_structure(0).get_value("height")
        width = caps.get_structure(0).get_value("width")

        success, map_info = buffer.map(Gst.MapFlags.READ)
        if not success:
            print("Buffer data could not be mapped.")
        
        image = np.ndarray(
            shape=(height, width, 3),
            dtype=np.uint8,
            buffer=map_info.data)
            
        buffer.unmap(map_info)
    return Gst.FlowReturn.OK

Attach the call back function:

appsink = gst_pipeline.get_by_name(‘appsink’)
appsink.connect(“new-sample”, on_new_sample)

Start the pipeline:

gst_pipeline.set_state(Gst.State.PLAYING)

These are just the functions you need to run and there is a lot more for you to play around with and explore but with this code every time the pipeline gets a new buffer the call back function will fire and put the BGR image into the numpy array. These actions are async and should be made thread safe.