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Legacy example · Python · Version 1.0.0

ST 2110-20 Video Reception Demo

Demo application for receiving SMPTE ST 2110-20 uncompressed video streams using Linux sockets with CUDA pinned memory and GPU-accelerated color conversion

AuthorsXRlabs (XRlabs)
Supported platformsx86_64, aarch64
LanguagePython
Version1.0.0
CompatibilityHSDK 3.11
Contribution levelLevel 2 · Quality code
SourceHoloHub

Legacy HoloHub application

This application comes from HoloHub and was last tested with Holoscan SDK (HSDK) 3.11. It runs with the HoloHub CLI, ./holohub.

ST 2110 Demo

Demo application for receiving SMPTE ST 2110-20 uncompressed video streams over IP networks using the ST2110SourceOp operator.

Overview

This application demonstrates ST 2110-20 video reception by:

  1. Receiving ST 2110-20 RTP packets via Linux UDP sockets (multicast)
  2. Reassembling packets into complete video frames
  3. Converting from YCbCr-4:2:2-10bit to RGBA and/or NV12 using CUDA kernels
  4. Displaying the video stream using Holoviz

Quick Start

# Build and run with holohub CLI
./holohub run st2110_demo

# Or run a specific mode
./holohub run st2110_demo rgba   # RGBA output only
./holohub run st2110_demo nv12   # NV12 output only

Before running, configure your network settings in the YAML config file (see Configuration below).

Prerequisites

  • CUDA-capable NVIDIA GPU
  • Network interface with multicast support
  • ST 2110-20 video source (see Testing with GStreamer for a software-based source)

Build Instructions

# Build the demo application (includes the st2110_source operator)
./holohub build st2110_demo

Configuration

Edit applications/st2110_demo/st2110_demo_config.yaml to match your network setup:

st2110_source:
  # Network parameters - update these for your setup
  multicast_address: "239.255.66.60"  # Your ST 2110 multicast address
  port: 16388                          # Your ST 2110 UDP port
  interface_name: "eth0"               # Your network interface name

  # Video parameters - match your ST 2110 source
  width: 1920
  height: 1080
  framerate: 50
  stream_format: "YCbCr-4:2:2-10bit"

  # Output format options
  enable_rgba_output: true   # Enable RGBA conversion for display
  enable_nv12_output: true   # Enable NV12 conversion for encoding

Finding Your Network Interface

# List network interfaces
ip link show

# Common interface names:
#   eth0, ens1f0     - standard Ethernet
#   mgbe0_0          - NVIDIA Thor AGX MGBE
#   enp1s0f0np0      - ConnectX SmartNIC

Run Modes

The application supports multiple run modes via the holohub CLI:

Mode Command Description
default ./holohub run st2110_demo Both RGBA and NV12 outputs displayed
rgba ./holohub run st2110_demo rgba RGBA output only
nv12 ./holohub run st2110_demo nv12 NV12 output only

Network Setup

Socket Buffer Size

Increase the socket buffer size for high-bandwidth streams:

# Temporary (until reboot)
sudo sysctl -w net.core.rmem_max=268435456
sudo sysctl -w net.core.rmem_default=268435456

# Permanent (add to /etc/sysctl.conf)
echo "net.core.rmem_max=268435456" | sudo tee -a /etc/sysctl.conf
echo "net.core.rmem_default=268435456" | sudo tee -a /etc/sysctl.conf

Multicast Routing

Ensure multicast traffic is routed to the correct interface:

# Replace <interface> with your network interface name
sudo ip route add 239.0.0.0/8 dev <interface>

# Verify multicast group membership
ip maddr show dev <interface>

Firewall

Allow UDP traffic on your ST 2110 port:

sudo ufw allow 16388/udp

Testing with GStreamer

You can test the operator without professional ST 2110 hardware by using GStreamer to generate a synthetic RTP video stream. This requires two machines (or two network namespaces) connected over a network.

Sender Setup

On the sending machine, install GStreamer and start a test stream:

# Install GStreamer (Ubuntu/Debian)
sudo apt-get install -y gstreamer1.0-tools gstreamer1.0-plugins-base \
                        gstreamer1.0-plugins-good

# Configure multicast routing on the sender's interface
sudo ip route add 239.0.0.0/8 dev <interface>

# Start a 1080p25 UYVY test pattern (bouncing ball)
gst-launch-1.0 videotestsrc pattern=ball ! \
  "video/x-raw,format=UYVY,width=1920,height=1080,framerate=25/1" ! \
  rtpvrawpay ! \
  udpsink host=239.255.66.60 port=16388 \
    multicast-iface=<interface> auto-multicast=true

Receiver Setup

On the receiving machine, configure the network and update the demo config:

# Increase socket buffer
sudo sysctl -w net.core.rmem_max=268435456
sudo sysctl -w net.core.rmem_default=268435456

# Configure multicast routing
sudo ip route add 239.0.0.0/8 dev <interface>

Update st2110_demo_config.yaml to match the GStreamer sender:

st2110_source:
  multicast_address: "239.255.66.60"
  port: 16388
  interface_name: "<interface>"
  width: 1920
  height: 1080
  framerate: 25
  stream_format: "YCbCr-4:2:2-8bit"   # UYVY is 8-bit YCbCr-4:2:2
  enable_rgba_output: true
  enable_nv12_output: false

Then run the demo:

./holohub run st2110_demo rgba

Verifying Packet Reception

To confirm multicast packets are arriving on the receiver:

sudo tcpdump -i <interface> dst 239.255.66.60 and udp port 16388 -c 10

Note: GStreamer's rtpvrawpay produces RFC 4175 RTP packets, which are similar but not identical to SMPTE ST 2110-20. For full end-to-end frame display, use a professional ST 2110 source (e.g., Blackmagic Design equipment).

Expected Behavior

When working correctly with a compatible ST 2110 source:

  1. Holoviz windows open showing the video stream
  2. Console logs showing frame reception stats
  3. Frame rate matches your source (e.g., 50 FPS for 1080p50)

Press ESC or Ctrl+C to quit.

Troubleshooting

No Video Displayed

  1. Verify source is streaming:
sudo tcpdump -i <interface> dst 239.255.66.60 and udp port 16388 -c 10

  1. Check interface name in config matches your system: ip link show

  2. Verify multicast routing: ip route show | grep 239

  3. Disable reverse path filtering if packets appear in tcpdump but the app reports 0 packets:

sudo sysctl -w net.ipv4.conf.<interface>.rp_filter=0
sudo sysctl -w net.ipv4.conf.all.rp_filter=0

Packet Drops / Frame Tearing

  • Increase socket buffer size (see Network Setup)
  • Reduce other network traffic on the interface
  • Check CPU load - ensure sufficient resources available

"Cannot import ST2110SourceOp" Error

Ensure the demo has been built:

./holohub build st2110_demo

Color Issues

  • Verify stream_format in config matches your source (10-bit vs 8-bit)
  • The operator assumes BT.709 colorimetry
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