WHEP Gateway — v1.11.0-alpha4
Released: 17 June 2026
Download: https://downloads.clouds3.uk/whep-gateway-v1.11.0-alpha4.iso
Base: Debian 13 (Trixie), kernel 6.19.13 — same FFmpeg-OMT binary as alpha3

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HEADLINE FIX — OMT / NDI output decouple
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If a channel sends NDI and/or OMT output, those network outputs now run in a
SEPARATE process from the WHEP encoder.

Why it matters:
  Previously the OMT output was muxed inside the main encode pipeline, and OMT's
  TCP send could block the shared output thread. Under load — e.g. NDI in + NDI
  out + OMT out + several RTMP/SRT restreams — the WHEP encode would fall below
  real-time and the channel would restart-loop, even with the CPU mostly idle.
  It was a blocking stall, not a compute shortage.

Now:
  WHEP holds real-time no matter what the NDI/OMT receivers do. A blocking/slow
  native send only ever stalls its own sidecar process — never the WHEP stream.
  Verified live at 1.0x with NDI out + OMT out + 4 simultaneous restreams.

  * Automatic — there is no setting to remember. The channel card shows
    "NDI / OMT output runs decoupled (automatic — no encode back-pressure)".
  * Stereo downmix and per-pair audio routing on NDI/OMT outputs are preserved.
  * AJA NDI (GStreamer ndisink) and WHIP-ingest native output are unaffected.

Carried over from alpha2/alpha3: per-output Copy/Transcode on restream outputs,
multi-pair SRT audio to NDI/OMT, and live CEA-608/708 closed captions + the
downloadable .vtt transcript.

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TIERS
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30-day trial = Pro (NDI/SRT/WHIP/OMT ingest, WHEP playback, NDI/OMT output,
RTMP/SRT restream, GPU encode, 16 channels).
Ultra adds DeckLink/AJA capture, DVR + Instant Replay, Enhanced-RTMP
(HEVC/AV1/VP9 restream), 32 channels.

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NOTES
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* HEVC encoding needs a GPU (Intel QSV / NVIDIA NVENC / AMD VAAPI) — there is no
  software H.265. H.264, AV1 and VP9 all have CPU fallbacks.
* On a GPU-less box the hardware codec options are greyed out as
  "not available on this system" — that is expected, not a build problem.
* This is an ALPHA test build. Not for production.

Known limitation: a sustained omt_send block from a dead OMT receiver can still
back-pressure the channel; the decouple absorbs the transient stalls that caused
the real-world problem, and is strictly better than the old in-process path.