Running this code results in the following error message:
(python3:3305): GStreamer-CRITICAL **: 17:15:11.086: Element nvstreamdemux already has a pad named src_0. The behavior of gst_element_get_request_pad() for existing pads is undefined.
the code attempts to request a pad that has already been created. My intention is to dynamically add a new source during runtime, and I’ve made some modifications to the code to achieve this. However, I encountered an issue where the code returns ‘None’ when attempting to request a demux pad during runtime.
#!/usr/bin/env python3
################################################################################
# SPDX-FileCopyrightText: Copyright (c) 2022 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: Apache-2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
################################################################################
import sys
sys.path.append("../")
import gi
import configparser
import argparse
gi.require_version("Gst", "1.0")
from gi.repository import Gst
from gi.repository import GLib
from ctypes import *
import time
import _thread as thread
import sys
import os
import math
import platform
from common.is_aarch_64 import is_aarch64
from common.bus_call import bus_call
from common.FPS import PERF_DATA
import pyds
no_display = False
silent = False
file_loop = False
perf_data = None
input_sources =[]
MAX_DISPLAY_LEN = 64
PGIE_CLASS_ID_VEHICLE = 0
PGIE_CLASS_ID_BICYCLE = 1
PGIE_CLASS_ID_PERSON = 2
PGIE_CLASS_ID_ROADSIGN = 3
MUXER_OUTPUT_WIDTH = 540
MUXER_OUTPUT_HEIGHT = 540 # 1080
MUXER_BATCH_TIMEOUT_USEC = 4000000
TILED_OUTPUT_WIDTH = 640 # 1280
TILED_OUTPUT_HEIGHT = 360 # 720
GST_CAPS_FEATURES_NVMM = "memory:NVMM"
OSD_PROCESS_MODE = 0
OSD_DISPLAY_TEXT = 1
pgie_classes_str = ["Vehicle", "TwoWheeler", "Person", "RoadSign"]
def pgie_src_pad_buffer_probe(pad, info, u_data):
"""
The function pgie_src_pad_buffer_probe() is a callback function that is called every time a buffer
is received on the source pad of the pgie element.
The function calculate the batch metadata from the buffer and iterates through the list of frame
metadata in the batch.
For each frame, it iterates through the list of object metadata and prints the frame number, number
of objects detected, and the number of vehicles, persons, bicycles, and road signs detected in the
frame.
The function also retrieves the frame rate of the stream from the frame metadata
:param pad: The pad on which the probe is attached
:param info: The Gst.PadProbeInfo object that contains the buffer
:param u_data: User data passed to the probe
:return: The return value is a Gst.PadProbeReturn.OK.
"""
frame_number = 0
num_rects = 0
gst_buffer = info.get_buffer()
if not gst_buffer:
print("Unable to get GstBuffer ")
return
# Retrieve batch metadata from the gst_buffer
# Note that pyds.gst_buffer_get_nvds_batch_meta() expects the
# C address of gst_buffer as input, which is obtained with hash(gst_buffer)
batch_meta = pyds.gst_buffer_get_nvds_batch_meta(hash(gst_buffer))
l_frame = batch_meta.frame_meta_list
while l_frame is not None:
try:
# Note that l_frame.data needs a cast to pyds.NvDsFrameMeta
# The casting is done by pyds.NvDsFrameMeta.cast()
# The casting also keeps ownership of the underlying memory
# in the C code, so the Python garbage collector will leave
# it alone.
frame_meta = pyds.NvDsFrameMeta.cast(l_frame.data)
except StopIteration:
break
frame_number = frame_meta.frame_num
l_obj = frame_meta.obj_meta_list
num_rects = frame_meta.num_obj_meta
obj_counter = {
PGIE_CLASS_ID_VEHICLE: 0,
PGIE_CLASS_ID_PERSON: 0,
PGIE_CLASS_ID_BICYCLE: 0,
PGIE_CLASS_ID_ROADSIGN: 0,
}
while l_obj is not None:
try:
# Casting l_obj.data to pyds.NvDsObjectMeta
obj_meta = pyds.NvDsObjectMeta.cast(l_obj.data)
except StopIteration:
break
obj_counter[obj_meta.class_id] += 1
try:
l_obj = l_obj.next
except StopIteration:
break
# print(
# "Frame Number=",
# frame_number,
# "Number of Objects=",
# num_rects,
# "Vehicle_count=",
# obj_counter[PGIE_CLASS_ID_VEHICLE],
# "Person_count=",
# obj_counter[PGIE_CLASS_ID_PERSON],
# )
# Update frame rate through this probe
# stream_index = "stream{0}".format(frame_meta.pad_index)
# global perf_data
# perf_data.update_fps(stream_index)
try:
l_frame = l_frame.next
except StopIteration:
break
return Gst.PadProbeReturn.OK
def cb_newpad(decodebin, decoder_src_pad, data):
"""
The function is called when a new pad is created by the decodebin.
The function checks if the new pad is for video and not audio.
If the new pad is for video, the function checks if the pad caps contain NVMM memory features.
If the pad caps contain NVMM memory features, the function links the decodebin pad to the source bin
ghost pad.
If the pad caps do not contain NVMM memory features, the function prints an error message.
:param decodebin: The decodebin element that is creating the new pad
:param decoder_src_pad: The source pad created by the decodebin element
:param data: This is the data that was passed to the callback function. In this case, it is the
source_bin
"""
print("In cb_newpad\n")
caps = decoder_src_pad.get_current_caps()
gststruct = caps.get_structure(0)
gstname = gststruct.get_name()
source_bin = data
features = caps.get_features(0)
# Need to check if the pad created by the decodebin is for video and not
# audio.
print("gstname=", gstname)
if gstname.find("video") != -1:
# Link the decodebin pad only if decodebin has picked nvidia
# decoder plugin nvdec_*. We do this by checking if the pad caps contain
# NVMM memory features.
print("features=", features)
if features.contains("memory:NVMM"):
# Get the source bin ghost pad
bin_ghost_pad = source_bin.get_static_pad("src")
if not bin_ghost_pad.set_target(decoder_src_pad):
sys.stderr.write(
"Failed to link decoder src pad to source bin ghost pad\n"
)
else:
sys.stderr.write(" Error: Decodebin did not pick nvidia decoder plugin.\n")
def decodebin_child_added(child_proxy, Object, name, user_data):
"""
If the child added to the decodebin is another decodebin, connect to its child-added signal. If the
child added is a source, set its drop-on-latency property to True.
:param child_proxy: The child element that was added to the decodebin
:param Object: The object that emitted the signal
:param name: The name of the element that was added
:param user_data: This is a pointer to the data that you want to pass to the callback function
"""
print("Decodebin child added:", name, "\n")
if name.find("decodebin") != -1:
Object.connect("child-added", decodebin_child_added, user_data)
if "source" in name:
source_element = child_proxy.get_by_name("source")
if source_element.find_property("drop-on-latency") != None:
Object.set_property("drop-on-latency", True)
def create_source_bin(index, uri):
"""
It creates a GstBin, adds a uridecodebin to it, and connects the uridecodebin's pad-added signal to
a callback function
:param index: The index of the source bin
:param uri: The URI of the video file to be played
:return: A bin with a uri decode bin and a ghost pad.
"""
print("Creating source bin")
# Create a source GstBin to abstract this bin's content from the rest of the
# pipeline
bin_name = "source-bin-%02d" % index
print(bin_name)
nbin = Gst.Bin.new(bin_name)
if not nbin:
sys.stderr.write(" Unable to create source bin \n")
# Source element for reading from the uri.
# We will use decodebin and let it figure out the container format of the
# stream and the codec and plug the appropriate demux and decode plugins.
uri_decode_bin = Gst.ElementFactory.make("uridecodebin", "uri-decode-bin")
if not uri_decode_bin:
sys.stderr.write(" Unable to create uri decode bin \n")
# We set the input uri to the source element
uri_decode_bin.set_property("uri", uri)
# Connect to the "pad-added" signal of the decodebin which generates a
# callback once a new pad for raw data has beed created by the decodebin
uri_decode_bin.connect("pad-added", cb_newpad, nbin)
uri_decode_bin.connect("child-added", decodebin_child_added, nbin)
# We need to create a ghost pad for the source bin which will act as a proxy
# for the video decoder src pad. The ghost pad will not have a target right
# now. Once the decode bin creates the video decoder and generates the
# cb_newpad callback, we will set the ghost pad target to the video decoder
# src pad.
Gst.Bin.add(nbin, uri_decode_bin)
bin_pad = nbin.add_pad(Gst.GhostPad.new_no_target("src", Gst.PadDirection.SRC))
if not bin_pad:
sys.stderr.write(" Failed to add ghost pad in source bin \n")
return None
return nbin
def make_element(element_name, i):
"""
Creates a Gstreamer element with unique name
Unique name is created by adding element type and index e.g. `element_name-i`
Unique name is essential for all the element in pipeline otherwise gstreamer will throw exception.
:param element_name: The name of the element to create
:param i: the index of the element in the pipeline
:return: A Gst.Element object
"""
ele_name = element_name + str(i)
element = Gst.ElementFactory.make(element_name, ele_name)
if not element:
sys.stderr.write(" Unable to create {0}".format(element_name))
element.set_property("name", "{0}-new{1}".format(element_name, str(i)))
return element
def create_sink_bin(index):
bin_name = "sink-bin-%02d" % index
print(bin_name)
nbin = Gst.Bin.new(bin_name)
if is_aarch64():
print("Creating nv3dsink \n")
sink = make_element("nv3dsink", index)
if not sink:
sys.stderr.write(" Unable to create nv3dsink \n")
else:
print("Creating EGLSink \n")
sink = make_element("nveglglessink", index)
if not sink:
sys.stderr.write(" Unable to create egl sink \n")
Gst.Bin.add(nbin, sink)
queue = make_element("queue", index)
Gst.Bin.add(nbin,queue)
nvvideoconvert = make_element("nvvideoconvert", index)
nbin.add(nvvideoconvert)
nvdsosd = make_element("nvdsosd", index)
nvdsosd.set_property("process-mode", OSD_PROCESS_MODE)
nvdsosd.set_property("display-text", OSD_DISPLAY_TEXT)
nbin.add(nvdsosd)
queue.link(nvvideoconvert)
nvvideoconvert.link(nvdsosd)
nvdsosd.link(sink)
sink.set_property("qos", 0)
queuesinkpad = queue.get_static_pad("sink")
if not queuesinkpad:
sys.stderr.write("Unable to create queue sink pad \n")
bin_pad = nbin.add_pad(Gst.GhostPad("sink", queuesinkpad))
if not bin_pad:
sys.stderr.write("sink bin Failed to add ghost pad in source bin \n")
return None
return nbin
def stop_sink(pipeline, i):
sink_bin = pipeline.get_by_name("sink-bin-%02d" % i)
if not sink_bin:
sys.stderr.write("Stop does not get the sink")
sinkpad = sink_bin.get_static_pad("sink")
sinkpad.send_event(Gst.Event.new_flush_stop(False))
pipeline.remove(sink_bin)
sink_bin.set_state(Gst.State.NULL)
while sink_bin.get_state(0.1)[1] != Gst.State.NULL:
time.sleep(0.1)
demux = pipeline.get_by_name("nvstreamdemux")
if not demux:
sys.stderr.write("Stop does not get the demux")
padname = "src_%u" % i
demuxsrcpad = demux.get_request_pad(padname)
if not demuxsrcpad:
print("STop the demux pad has existed")
demuxsrcpad = demux.get_static_pad(padname)
if not demuxsrcpad:
sys.stderr.write("STop the demux pad static get fail")
if is_aarch64():
sink = sink_bin.get_by_name("nv3dsink-new%u" % i)
else:
sink = sink_bin.get_by_name("nveglglessink-new%u" % i)
queue = sink_bin.get_by_name("queue-new%u" % i)
if not queue:
sys.stderr.write("Stop does not get the queue")
queuesinkpad = queue.get_static_pad("sink")
videoconvert = sink_bin.get_by_name("nvvideoconvert-new%u" % i)
nvosd = sink_bin.get_by_name("nvdsosd-new%u" % i)
ret = demuxsrcpad.unlink(queuesinkpad)
if not ret:
print("Stop the pads are not linked")
sink_bin.remove(sink)
sink_bin.remove(queue)
sink_bin.remove(videoconvert)
sink_bin.remove(nvosd)
print("Stop the sink %u" % i)
def start_sink(pipeline,i):
source_bin = create_source_bin(i, input_sources[0])
if not source_bin:
sys.stderr.write("Unable to create source bin \n")
pipeline.add(source_bin)
padname = "sink_%u" % i
streammux = pipeline.get_by_name("Stream-muxer")
sinkpad = streammux.get_request_pad(padname)
if not sinkpad:
sys.stderr.write("Unable to create sink pad bin \n")
srcpad = source_bin.get_static_pad("src")
if not srcpad:
sys.stderr.write("Unable to create src pad bin \n")
srcpad.link(sinkpad)
source_bin.set_state(Gst.State.PLAYING)
print("Start sink %u" % i)
sink_bin = create_sink_bin(i)
if not sink_bin:
sys.stderr.write("Unable to create sink bin \n")
pipeline.add(sink_bin)
padname = "src_%u" % i
streamdemux = pipeline.get_by_name("nvstreamdemux")
demuxsrcpad = streamdemux.get_request_pad(padname)
if not demuxsrcpad:
sys.stderr.write("THREAD Unable to create demux src pad \n")
demuxsrcpad = streamdemux.get_static_pad(padname)
if not demuxsrcpad:
sys.stderr.write("STart the demux pad static get fail")
print('debug 1 ----------->', demuxsrcpad)
binsinkpad = sink_bin.get_static_pad("sink")
if not binsinkpad:
sys.stderr.write("Unable to create sink bin sink pad \n")
pad_ret = demuxsrcpad.link(binsinkpad)
if pad_ret:
print("demux src %u pad connected %u" % i % pad_ret)
ret = sink_bin.sync_state_with_parent()
if not ret:
print("the state of element is undefined.")
def new_thread(pipeline):
print("##Start setting thread")
while pipeline.get_state(0.0)[1] !=\
Gst.State.PLAYING:
time.sleep(0.2)
Gst.debug_bin_to_dot_file(pipeline, Gst.DebugGraphDetails.ALL, "playing_pipeline")
print("Set the GRAPH dump parameter")
time.sleep(60)
start_sink(pipeline,2)
time.sleep(10)
stop_sink(pipeline,0)
time.sleep(10)
stop_sink(pipeline,2)
def main(args, requested_pgie=None, config=None, disable_probe=False):
input_sources = args
number_sources = len(input_sources)
global perf_data
# perf_data = PERF_DATA(number_sources)
# Standard GStreamer initialization
Gst.init(None)
# Create gstreamer elements */
# Create Pipeline element that will form a connection of other elements
print("Creating Pipeline \n ")
pipeline = Gst.Pipeline()
is_live = False
if not pipeline:
sys.stderr.write(" Unable to create Pipeline \n")
print("Creating streamux \n ")
# Create nvstreammux instance to form batches from one or more sources.
streammux = Gst.ElementFactory.make("nvstreammux", "Stream-muxer")
if not streammux:
sys.stderr.write(" Unable to create NvStreamMux \n")
pipeline.add(streammux)
for i in range(number_sources):
print("Creating source_bin ", i, " \n ")
uri_name = input_sources[i]
if uri_name.find("rtsp://") == 0:
is_live = True
source_bin = create_source_bin(i, uri_name)
if not source_bin:
sys.stderr.write("Unable to create source bin \n")
pipeline.add(source_bin)
padname = "sink_%u" % i
sinkpad = streammux.get_request_pad(padname)
if not sinkpad:
sys.stderr.write("Unable to create sink pad bin \n")
srcpad = source_bin.get_static_pad("src")
if not srcpad:
sys.stderr.write("Unable to create src pad bin \n")
srcpad.link(sinkpad)
queue1 = Gst.ElementFactory.make("queue", "queue1")
pipeline.add(queue1)
print("Creating Pgie \n ")
pgie = Gst.ElementFactory.make("nvinfer", "primary-inference")
if not pgie:
sys.stderr.write(" Unable to create pgie \n")
print("Creating nvstreamdemux \n ")
nvstreamdemux = Gst.ElementFactory.make("nvstreamdemux", "nvstreamdemux")
if not nvstreamdemux:
sys.stderr.write(" Unable to create nvstreamdemux \n")
if is_live:
print("Atleast one of the sources is live")
streammux.set_property("live-source", 1)
streammux.set_property("width", 960)
streammux.set_property("height", 540)
streammux.set_property("batch-size", number_sources)
streammux.set_property("batched-push-timeout", 4000000)
pgie.set_property("config-file-path", "ds_demux_pgie_config.txt")
pgie_batch_size = pgie.get_property("batch-size")
if pgie_batch_size != number_sources:
print(
"WARNING: Overriding infer-config batch-size",
pgie_batch_size,
" with number of sources ",
number_sources,
" \n",
)
pgie.set_property("batch-size", number_sources)
print("Adding elements to Pipeline \n")
pipeline.add(pgie)
pipeline.add(nvstreamdemux)
# linking
streammux.link(queue1)
queue1.link(pgie)
pgie.link(nvstreamdemux)
##creating demux src
for i in range(number_sources):
# pipeline nvstreamdemux -> queue -> nvvidconv -> nvosd -> (if Jetson) nvegltransform -> nveglgl
# Creating EGLsink
sink_bin = create_sink_bin(i)
#sink_bin = Gst.ElementFactory.make("fakesink", "fakesink-%u" % i)
if not sink_bin:
sys.stderr.write("Unable to create sink bin \n")
pipeline.add(sink_bin)
#sink_bin.set_property("sync", 0)
padname = "src_%u" % i
demuxsrcpad = nvstreamdemux.get_request_pad(padname)
if not demuxsrcpad:
sys.stderr.write("Unable to create demux src pad \n")
#queue = Gst.ElementFactory.make("queue", "queue-%u" % i)
#pipeline.add(queue)
#queue.link(sink_bin)
binsinkpad = sink_bin.get_static_pad("sink")
if not binsinkpad:
sys.stderr.write("Unable to create sink bin sink pad \n")
pad_ret = demuxsrcpad.link(binsinkpad)
if pad_ret:
print("demux src %u pad connected %u" % i % pad_ret)
print("Linking elements in the Pipeline \n")
#GLib.timeout_add(20, self.)
# create an event loop and feed gstreamer bus mesages to it
loop = GLib.MainLoop()
bus = pipeline.get_bus()
bus.add_signal_watch()
bus.connect("message", bus_call, loop)
pgie_src_pad = pgie.get_static_pad("src")
if not pgie_src_pad:
sys.stderr.write(" Unable to get src pad \n")
else:
pgie_src_pad.add_probe(Gst.PadProbeType.BUFFER, pgie_src_pad_buffer_probe, 0)
# perf callback function to print fps every 5 sec
# GLib.timeout_add(5000, perf_data.perf_print_callback)
os.environ["GST_DEBUG_DUMP_DOT_DIR"] = "/home/fechen"
os.putenv('GST_DEBUG_DUMP_DIR_DIR', '/home/fechen')
# List the sources
print("Now playing...")
for i, source in enumerate(input_sources):
print(i, ": ", source)
print("Starting pipeline \n")
# start play back and listed to events
thread.start_new_thread(new_thread,(pipeline,))
pipeline.set_state(Gst.State.PLAYING)
print("Set state to PLAYING")
try:
loop.run()
except:
pass
# cleanup
print("Exiting app\n")
pipeline.set_state(Gst.State.NULL)
def parse_args():
parser = argparse.ArgumentParser(prog="deepstream_demux_multi_in_multi_out.py",
description="deepstream-demux-multi-in-multi-out takes multiple URI streams as input" \
"and uses `nvstreamdemux` to split batches and output separate buffer/streams")
parser.add_argument(
"-i",
"--input",
help="Path to input streams",
nargs="+",
metavar="URIs",
default=["a"],
required=True,
)
args = parser.parse_args()
stream_paths = args.input
return stream_paths
if __name__ == "__main__":
stream_paths = parse_args()
sys.exit(main(stream_paths))