Segfault when `nvvideoconvert` and `nvv4l2h265enc` are used together

Accelerated Computing Intelligent Video Analytics DeepStream SDK
1

• Hardware Platform (Jetson / GPU): Jetson Nano
• DeepStream Version: 5.0.1
• JetPack Version (valid for Jetson only): 4.4
• TensorRT Version: N/A
• NVIDIA GPU Driver Version (valid for GPU only): N/A
• Issue Type( questions, new requirements, bugs): bug
• How to reproduce the issue ?: Described below
• Requirement details: N/A

Segmentation fault is caused when nvv4l2h265enc and nvvideoconvert are used together.
More specifically, in my observation, it is caused when the following conditions are met:

  • nvvideoconvert element is instantiated. (not necessarily added to a gstreamer pipeline)
  • nvv4l2h265enc (or nvv4l2h264enc) is running in a pipeline.

Details:

Code 
import sys
import time
​
import gi
gi.require_version('Gst', '1.0')
from gi.repository import GObject, Gst
​
​
def make_gst_element(factoryname, name=None, *, props=None):
    if name is None:
        name = factoryname
    element = Gst.ElementFactory.make(factoryname, name)
    if not element:
        raise RuntimeError(f"Unable to create streamer element: {factoryname}")
    if props:
        for key, value in props.items():
            element.set_property(key, value)
    return element
​
​
def main():
    GObject.threads_init()
    Gst.init(None)
​
    # Set True to cause segfault.
    bad = True
​
    # Create pipeline
    pipeline = Gst.Pipeline()
    if not pipeline:
        raise RuntimeError("Unable to create Pipeline")
​
    source = make_gst_element(
        "nvarguscamerasrc",
        props={
            'sensor-id': 0,
        })
​
    image_width = 816
    image_height = 616
    capsfilter = make_gst_element(
        "capsfilter",
        props={
            "caps": Gst.Caps.from_string(f"video/x-raw(memory:NVMM), width=(int){image_width}, height=(int){image_height}, format=(string)NV12, framerate=(fraction)21/1"),
        }
    )
    if bad:
        encoder = make_gst_element("nvv4l2h265enc")
    fakesink = make_gst_element("fakesink")
​
    # Only instantiated (not even added to the pipeline)
    make_gst_element("nvvideoconvert")
​
    # Add to pipeline
    pipeline.add(source)
    pipeline.add(capsfilter)
    pipeline.add(fakesink)
    if bad:
        pipeline.add(encoder)
​
    # Link
    source.link(capsfilter)
    if bad:
        capsfilter.link(encoder)
        encoder.link(fakesink)
    else:
        capsfilter.link(fakesink)
​
    # Start
    if pipeline.set_state(Gst.State.PLAYING) == Gst.StateChangeReturn.FAILURE:
        raise RuntimeError('Unable to start gstreamer pipeline')
​
    try:
        while True:
            time.sleep(10)
    finally:
        pipeline.set_state(Gst.State.NULL)
​
​
if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        sys.exit(1)
    except:
        import traceback
        traceback.print_exc()
        import pdb
        pdb.post_mortem()
Output 
$ GST_DEBUG=3 python3 bad.py
Opening in BLOCKING MODE                                                                                                                                                                                 
0:00:00.116061984  3673     0x317dbb60 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x31777a40 Failed to determine interlace mode
0:00:00.116144485  3673     0x317dbb60 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x31777a40 Failed to determine interlace mode
0:00:00.116214069  3673     0x317dbb60 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0x31777a40 Failed to determine interlace mode
0:00:00.116334019  3673     0x317dbb60 WARN                    v4l2 gstv4l2object.c:4430:gst_v4l2_object_probe_caps:<nvv4l2h265enc:src> Failed to probe pixel aspect ratio with VIDIOC_CROPCAP: Unknown err
or -1                                             
0:00:00.116905329  3673     0x314dc8a0 FIXME                default gstutils.c:3981:gst_pad_create_stream_id_internal:<nvarguscamerasrc:src> Creating random stream-id, consider implementing a determinist
ic way of creating a stream-id                                                                                                                         
NvMMLiteOpen : Block : BlockType = 8                                                                                                                  
===== NVMEDIA: NVENC =====                                                                                                                             
NvMMLiteBlockCreate : Block : BlockType = 8                                                                                                           
0:00:00.139390069  3673     0x314dc8a0 WARN          v4l2bufferpool gstv4l2bufferpool.c:1057:gst_v4l2_buffer_pool_start:<nvv4l2h265enc:pool:src> Uncertain or not enough buffers, enabling copy threshold
GST_ARGUS: Creating output stream                   
CONSUMER: Waiting until producer is connected...                                                                                                      
GST_ARGUS: Available Sensor modes :     
GST_ARGUS: 3264 x 2464 FR = 21.000000 fps Duration = 47619048 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;
                                                 
GST_ARGUS: 3264 x 1848 FR = 28.000001 fps Duration = 35714284 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;
                                                               
GST_ARGUS: 1920 x 1080 FR = 29.999999 fps Duration = 33333334 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;
                                             
GST_ARGUS: 1280 x 720 FR = 59.999999 fps Duration = 16666667 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;
                                         
GST_ARGUS: 1280 x 720 FR = 120.000005 fps Duration = 8333333 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;
                                                                           
GST_ARGUS: Running with following settings:
   Camera index = 0
   Camera mode  = 4
   Output Stream W = 1280 H = 720
   seconds to Run    = 0
   Frame Rate = 120.000005
GST_ARGUS: Setup Complete, Starting captures for 0 seconds
GST_ARGUS: Starting repeat capture requests.
CONSUMER: Producer has connected; continuing.
Segmentation fault (core dumped)
Output (gdb) 
(gdb) cont
Continuing.
[New Thread 0x7fb40631f0 (LWP 7260)]
[New Thread 0x7fb38621f0 (LWP 7261)]
[New Thread 0x7fb30611f0 (LWP 7262)]
[New Thread 0x7fb28601f0 (LWP 7263)]
[New Thread 0x7fafd741f0 (LWP 7264)]
Opening in BLOCKING MODE
0:00:00.652504935  6775       0xde3760 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0xd7ed00 Failed to determine interlace mode
0:00:00.652594988  6775       0xde3760 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0xd7ed00 Failed to determine interlace mode
0:00:00.652647020  6775       0xde3760 WARN                    v4l2 gstv4l2object.c:2372:gst_v4l2_object_add_interlace_mode:0xd7ed00 Failed to determine interlace mode
0:00:00.652744782  6775       0xde3760 WARN                    v4l2 gstv4l2object.c:4430:gst_v4l2_object_probe_caps:<nvv4l2h265enc:src> Failed to probe pixel aspect ratio with VIDIOC_CROPCAP: Unknown error -1
[New Thread 0x7faf3ac1f0 (LWP 7265)]
0:00:00.653799692  6775       0xae34a0 FIXME                default gstutils.c:3981:gst_pad_create_stream_id_internal:<nvarguscamerasrc:src> Creating random stream-id, consider implementing a deterministic way of creating a stream-id
[New Thread 0x7faebab1f0 (LWP 7266)]
[New Thread 0x7fae3aa1f0 (LWP 7267)]
NvMMLiteOpen : Block : BlockType = 8
===== NVMEDIA: NVENC =====
NvMMLiteBlockCreate : Block : BlockType = 8
[New Thread 0x7fadba91f0 (LWP 7269)]
0:00:00.677425387  6775       0xae34a0 WARN          v4l2bufferpool gstv4l2bufferpool.c:1057:gst_v4l2_buffer_pool_start:<nvv4l2h265enc:pool:src> Uncertain or not enough buffers, enabling copy threshold
GST_ARGUS: Creating output stream
[New Thread 0x7f8ffff1f0 (LWP 7409)]
[New Thread 0x7f8f7fe1f0 (LWP 7410)]
[New Thread 0x7f8effd1f0 (LWP 7411)]
CONSUMER: Waiting until producer is connected...
GST_ARGUS: Available Sensor modes :
GST_ARGUS: 3264 x 2464 FR = 21.000000 fps Duration = 47619048 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;

GST_ARGUS: 3264 x 1848 FR = 28.000001 fps Duration = 35714284 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;

GST_ARGUS: 1920 x 1080 FR = 29.999999 fps Duration = 33333334 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;

GST_ARGUS: 1280 x 720 FR = 59.999999 fps Duration = 16666667 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;

GST_ARGUS: 1280 x 720 FR = 120.000005 fps Duration = 8333333 ; Analog Gain range min 1.000000, max 10.625000; Exposure Range min 13000, max 683709000;

GST_ARGUS: Running with following settings:
   Camera index = 0
   Camera mode  = 4
   Output Stream W = 1280 H = 720
   seconds to Run    = 0
   Frame Rate = 120.000005
GST_ARGUS: Setup Complete, Starting captures for 0 seconds
GST_ARGUS: Starting repeat capture requests.
CONSUMER: Producer has connected; continuing.
[New Thread 0x7f8e7fc1f0 (LWP 7414)]

Thread 7 "nvarguscamerasr" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7faf3ac1f0 (LWP 7265)]
0x0000007fb0a5f170 in ?? () from /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvvideo4linux2.so
(gdb) bt
#0  0x0000007fb0a5f170 in  () at /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvvideo4linux2.so
#1  0x0000007fb0a63458 in  () at /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvvideo4linux2.so
#2  0x0000007fb0a7700c in  () at /usr/lib/aarch64-linux-gnu/gstreamer-1.0/libgstnvvideo4linux2.so
#3  0x0000007fb68ae774 in  () at /usr/lib/aarch64-linux-gnu/libgstvideo-1.0.so.0
#4  0x0000000000b18e00 in  ()
3

nvvideoconvert and nvv4l2h265enc can work together.

The problem may be caused by nvarguscamerasrc. If you want to use nvarguscamerasrc and nvvideoconvert together, you need to set the property “bufapi-version” to true for nvarguscamerasrc.

1 Like
4

Thank you for a quick reply, that did the trick!

But what does the property mean?
I can’t find any documentation.

5

use “gst-inspect-1.0 nvarguscamerasrc” command to check the properties, there is some simple explanation.

1 Like
6

Thank you!