Introduce an optional ITU-R BS.412 MPX power limiter, tighten the low-pass/notch filter design around the protected composite path, and document the full DSP architecture and recommended Pluto configuration in detail.
Rework the DSP chain to a clip-filter-clip architecture with cascaded 14 kHz low-pass stages, double 19/57 kHz protection notches, fixed pilot/RDS injection semantics, and explicit MPX gain calibration support. Update config defaults and tests to match the new broadcast-style modulation budgeting and protected composite path.
Add a lock-free stdin PCM ingest path, streaming resampler, stereo-linked limiting and pre-MPX audio filtering, plus the engine/control wiring needed to drive live audio into TX mode. Also document the ingest API and include a helper batch script for piping ffmpeg audio into fmrtx.
Document the HTTP API surface in detail, including runtime control, live config updates, split-rate behaviour, and the current hot-reload semantics for on-air parameter changes.
Keep DSP state persistent across generated frames, move the RDS encoder to arbitrary sample-rate operation, and tune the Pluto profile to the working 2.28 MHz path with the levels that finally decode reliably.
Jan
