Write opencv frames into gstreamer rtsp server pipeline

from threading import Thread from time import clock import cv2 import gi gi.require_version('Gst', '1.0') gi.require_version('GstRtspServer', '1.0') from gi.repository import Gst, GstRtspServer, GObject class SensorFactory(GstRtspServer.RTSPMediaFactory): def __init__(self, **properties): super(SensorFactory, self).__init__(**properties) self.launch_string = 'appsrc ! video/x-raw,width=320,height=240,framerate=30/1 ' \ '! videoconvert ! x264enc speed-preset=ultrafast tune=zerolatency ' \ '! rtph264pay config-interval=1 name=pay0 pt=96' self.pipeline = Gst.parse_launch(self.launch_string) self.appsrc = self.pipeline.get_child_by_index(4) def do_create_element(self, url): return self.pipeline class GstServer(GstRtspServer.RTSPServer): def __init__(self, **properties): super(GstServer, self).__init__(**properties) self.factory = SensorFactory() self.factory.set_shared(True) self.get_mount_points().add_factory("/test", self.factory) self.attach(None) GObject.threads_init() Gst.init(None) server = GstServer() loop = GObject.MainLoop() th = Thread(target=loop.run) th.start() print('Thread started') cap = cv2.VideoCapture(0) print(cap.isOpened()) frame_number = 0 fps = 30 duration = 1 / fps timestamp = clock() while cap.isOpened(): ret, frame = cap.read() if ret: print('Writing buffer') data = frame.tostring() buf = Gst.Buffer.new_allocate(None, len(data), None) buf.fill(0, data) buf.duration = fps timestamp = clock() - timestamp buf.pts = buf.dts = int(timestamp) buf.offset = frame_number frame_number += 1 retval = server.factory.appsrc.emit('push-buffer', buf) print(retval) if cv2.waitKey(1) & 0xFF == ord('q'): break cap.release()

I found the solution, lots of stuff was missing.

I used the need-data signal like the examples of gst-rtsp-server.
I changed some default parameters of appsrc, like the is-live, block and format.
The caps on the appsrc element.
I was not setting the offset of the buffer correctly.

Here's the code for anyone who's facing the same problem or has a somewhat similar one.

#!/usr/bin/env python3

import cv2
import gi

gi.require_version('Gst', '1.0')
gi.require_version('GstRtspServer', '1.0')
from gi.repository import Gst, GstRtspServer, GObject


class SensorFactory(GstRtspServer.RTSPMediaFactory):
    def __init__(self, **properties):
        super(SensorFactory, self).__init__(**properties)
        self.cap = cv2.VideoCapture(0)
        self.number_frames = 0
        self.fps = 30
        self.duration = 1 / self.fps * Gst.SECOND  # duration of a frame in nanoseconds
        self.launch_string = 'appsrc name=source is-live=true block=true format=GST_FORMAT_TIME ' \
                             'caps=video/x-raw,format=BGR,width=640,height=480,framerate={}/1 ' \
                             '! videoconvert ! video/x-raw,format=I420 ' \
                             '! x264enc speed-preset=ultrafast tune=zerolatency ' \
                             '! rtph264pay config-interval=1 name=pay0 pt=96'.format(self.fps)

    def on_need_data(self, src, lenght):
        if self.cap.isOpened():
            ret, frame = self.cap.read()
            if ret:
                data = frame.tostring()
                buf = Gst.Buffer.new_allocate(None, len(data), None)
                buf.fill(0, data)
                buf.duration = self.duration
                timestamp = self.number_frames * self.duration
                buf.pts = buf.dts = int(timestamp)
                buf.offset = timestamp
                self.number_frames += 1
                retval = src.emit('push-buffer', buf)
                print('pushed buffer, frame {}, duration {} ns, durations {} s'.format(self.number_frames,
                                                                                       self.duration,
                                                                                       self.duration / Gst.SECOND))
                if retval != Gst.FlowReturn.OK:
                    print(retval)

    def do_create_element(self, url):
        return Gst.parse_launch(self.launch_string)

    def do_configure(self, rtsp_media):
        self.number_frames = 0
        appsrc = rtsp_media.get_element().get_child_by_name('source')
        appsrc.connect('need-data', self.on_need_data)


class GstServer(GstRtspServer.RTSPServer):
    def __init__(self, **properties):
        super(GstServer, self).__init__(**properties)
        self.factory = SensorFactory()
        self.factory.set_shared(True)
        self.get_mount_points().add_factory("/test", self.factory)
        self.attach(None)


GObject.threads_init()
Gst.init(None)

server = GstServer()

loop = GObject.MainLoop()
loop.run()

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