RTSP Ingestion

RUSEON Core connects to IP cameras and RTSP streaming sources using bluenviron/gortsplib/v4 and pion/rtp.

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Connection Lifecycle

1. Dial Throttling: Connection handshakes pass through a concurrency semaphore (dialSemaphore, max 10 concurrent initial dials) to prevent Thundering Herd issues and network interface saturation when booting large camera fleets.
2. Describe & Setup: Issues RTSP DESCRIBE and sets up tracks via SETUP (using TCP interleaved transport by default, with configurable UDP mode).
3. Play & Read: Issues PLAY and registers packet callbacks:
   • OnPacketRTP: Parses RTP payload into NAL units.
   • OnPacketLost: Increments error counters and logs warnings without dropping the session.
   • OnDecodeError: Handles corrupted frames gracefully.

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Video Codec Processing

RUSEON Core demuxes video streams without CPU-intensive decoding:

• H.264 (AVC): Extracts SPS (type 7), PPS (type 8), and IDR slices (type 5).
• H.265 (HEVC): Extracts VPS (type 32), SPS (type 33), PPS (type 34), and IRAP/IDR slices (types 16–21).
• Bitrate Calculation: Calculated over a rolling 1-second window and reported in camera telemetry.

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Reconnection with Exponential Backoff & Jitter

When an RTSP connection drops:

1. Emits a camera_offline event over the EventBus and updates state to offline.
2. Initiates reconnection using an exponential backoff algorithm with jitter: $$\text{delay} = \min(60\text{s}, 1\text{s} \times 2^{\text{reconnectCount}}) \pm 20% \text{ jitter}$$
3. Prevents synchronised reconnect spikes against target camera servers.
4. Upon successful re-establishment, emits camera_online and transitions camera state back to online.