How to Transcode Video to SMPTE 2022-6 with FFmpeg

This article provides a practical guide on how to use FFmpeg to transcode and stream video to the SMPTE 2022-6 IP broadcast standard. You will learn the specific FFmpeg commands, video and audio codec configurations, and network transport settings required to packetize uncompressed SDI video over IP networks.

The FFmpeg Command for SMPTE 2022-6

SMPTE 2022-6 specifies the transport of high-bitrate, uncompressed SDI signals (including active video, audio, and ancillary data) over IP networks using RTP (Real-time Transport Protocol). Because SMPTE 2022-6 requires uncompressed SDI mapping, the video must be transcoded to a raw 10-bit 4:2:2 format (v210) and the audio to uncompressed PCM.

Use the following command structure to transcode a source video and stream it as an uncompressed RTP stream matching the SMPTE 2022-6 payload profile:

ffmpeg -re -i input.mp4 \
  -c:v v210 -pix_fmt yuv422p10le \
  -c:a pcm_s24be -ar 48000 \
  -f rtp rtp://239.1.1.1:5004?sdp_file=smpte2022.sdp

Parameter Breakdown

• -re: Read the input file in real-time. This is crucial when streaming to simulate a live broadcast feed.
• -c:v v210: Codec choice. The v210 codec is the industry standard for uncompressed 10-bit 4:2:2 digital video, matching physical SDI specifications.
• -pix_fmt yuv422p10le: Sets the pixel format to 10-bit YUV 4:2:2, which matches the chroma subsampling and bit depth of SMPTE broadcast standards.
• -c:a pcm_s24be: Audio codec. Broadcast SDI utilizes uncompressed 24-bit PCM Big-Endian audio.
• -ar 48000: Sets the audio sample rate to 48 kHz, the standard frequency for professional television production.
• -f rtp: Specifies the output format as RTP, which is the underlying transport protocol for SMPTE 2022-6.
• rtp://239.1.1.1:5004: The destination IP address (typically a multicast address in broadcast environments) and port.
• ?sdp_file=smpte2022.sdp: Instructs FFmpeg to output a Session Description Protocol (SDP) file. Receivers require this SDP file to correctly decode the uncompressed network stream.

Technical Considerations for Broadcast Environments

• Network Bandwidth: Uncompressed 10-bit 4:2:2 HD video (1080i or 1080p) requires substantial bandwidth. A 1080i60 stream requires approximately 1.5 Gbps of continuous throughput. Ensure your network switches, NICs (Network Interface Cards), and cabling are rated for 10 GbE or higher.
• Hardware Integration: Software-only FFmpeg can generate the RTP packetization for SMPTE 2022-6, but in enterprise environments, this is typically paired with hardware PCIe cards (such as AJA Kona or Blackmagic DeckLink) or virtual network interfaces (like NVIDIA Mellanox Rivermax) to offload packet pacing and prevent jitter.