mfsk-core 0.7.4

Pure-Rust WSJT-family decoders + synthesisers (FT8 FT4 FST4 WSPR JT9 JT65 Q65) behind a zero-cost Protocol trait. Host (rustfft) or no_std embedded (ESP32-S3, RP2350, Cortex-M) via a pluggable FFT backend; fixed-point hot path for FPU-less MCUs. Ships with embedded-poc/m5stack-s3-app, a working M5StickS3 FT8 controller (LCD UI, BLE CI-V to IC-705, acoustic mic, QSO FSM) decoding real on-air signals in ~1.2 s post-SlotEnd on Xtensa LX7.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35

//! Spectrum baseline estimator — historical FT8 entry point.
//!
//! The polynomial-fit implementation moved to
//! [`crate::core::baseline`] in 2026-05 (slice 1 of issue #18) so that
//! FT4's `coarse_sync` can normalise its candidate spectrum the same
//! way WSJT-X does (`ft4_baseline.f90`). The algorithm is identical
//! across FT8 / FT4 / FST4 in WSJT-X — keeping a single Rust port
//! avoids drift.
//!
//! This module is now a thin re-export plus the FT8-specific
//! [`avg_spectrum`] helper that consumes the embedded
//! [`crate::ft8::decode_block::Spectrogram`].

#![cfg(feature = "std")]

pub use crate::core::baseline::fit_baseline;

/// Compute the average linear power per FFT bin from a `Spectrogram`.
/// `out.len()` must equal `spec.n_freq`. FT8-specific because it
/// targets the embedded `decode_block::Spectrogram` layout.
pub fn avg_spectrum(spec: &crate::ft8::decode_block::Spectrogram, out: &mut [f32]) {
    debug_assert_eq!(out.len(), spec.n_freq);
    out.fill(0.0);
    for t in 0..spec.n_time {
        for f in 0..spec.n_freq {
            #[allow(clippy::unnecessary_cast)]
            let v = spec.data[t * spec.n_freq + f] as f32;
            out[f] += v;
        }
    }
    let inv = 1.0 / spec.n_time as f32;
    for v in out.iter_mut() {
        *v *= inv;
    }
}