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Send Video

Use VideoSender when a Graph should send video to an external receiver. VideoSender returns a reusable Graph fragment, so add it with Graph::add(...).

The current wire format is H.264 over RTP/UDP. The default UDP port rule is video_port_base + channel, with video_port_base = 9000. If the receiver runs behind container port remapping, pass the mapped host and a matching video_port_base from the app.

Raw Frames​

Use the raw path when the pipeline input to VideoSender is raw video frames. Neat converts, encodes, packetizes, and sends:

VideoConvert -> H264EncodeSima -> H264Parse -> H264Packetize -> UdpOutput
simaai::neat::Graph graph;
const int channel = 0;

auto opt = simaai::neat::nodes::groups::VideoSenderOptions::H264RtpUdpFromRaw(
    width, height, fps);
opt.host = "127.0.0.1";
opt.channel = channel;
opt.video_port_base = 9000;
opt.encoder.bitrate_kbps = 2500;

graph.add(simaai::neat::nodes::groups::VideoSender(opt));

Python:

channel = 0

opt = pyneat.VideoSenderOptions.h264_rtp_udp_from_raw(
    width=1920,
    height=1080,
    fps=30,
)
opt.host = "127.0.0.1"
opt.channel = channel
opt.video_port_base = 9000
opt.encoder.bitrate_kbps = 2500

graph = pyneat.Graph()
graph.add(pyneat.groups.video_sender(opt))

Encoded H.264​

Use the encoded path when the upstream pipeline already produces H.264. Neat parses, packetizes, and sends without re-encoding:

H264Parse -> H264Packetize -> UdpOutput
simaai::neat::Graph graph;
const int channel = 0;

auto opt = simaai::neat::nodes::groups::VideoSenderOptions::H264RtpUdpFromEncoded();
opt.host = "127.0.0.1";
opt.channel = channel;
opt.video_port_base = 9000;

graph.add(simaai::neat::nodes::groups::VideoSender(opt));

Python:

channel = 0

opt = pyneat.VideoSenderOptions.h264_rtp_udp_from_encoded()
opt.host = "127.0.0.1"
opt.channel = channel
opt.video_port_base = 9000

graph = pyneat.Graph()
graph.add(pyneat.groups.video_sender(opt))

Fan out encoded RTSP to inference and preview​

When one encoded RTSP source feeds both decoding/inference and VideoSender, connect the source directly to the sender. For a live preview such as Insight, set the encoded sender edge to RealtimeLatestByStream:

simaai::neat::GraphLinkOptions video_link;
video_link.policy = simaai::neat::GraphLinkPolicy::RealtimeLatestByStream;

graph.connect(encoded_source, decoder);
graph.connect(decoder, detector, detector_link);
graph.connect(encoded_source, video_sender, video_link);
video_link = pyneat.GraphLinkOptions()
video_link.policy = pyneat.GraphLinkPolicy.RealtimeLatestByStream

graph.connect(encoded_source, decoder)
graph.connect(decoder, detector, detector_link)
graph.connect(encoded_source, video_sender, video_link)

The sender branch stays before SimaDecode, so it does not re-encode video or copy decoded frames to CPU. With RealtimeLatestByStream, the fused sender branch keeps at most one pending H.264 access unit and replaces stale data if UDP egress slows. The default edge policy remains lossless and can backpressure the shared encoded source, including its decoder branch. Use the default only when preserving every access unit is more important than keeping live inference fresh.