The previous fix (f29ae3d) introduced a regression: when VIS parity
check failed or the VIS code was unrecognized, the detector entered
DETECTED state permanently and never resumed scanning. Now it resets
to IDLE on validation failure and only enters DETECTED on success.
Also resets partial image progress counter between consecutive decodes
and adds SDR device claiming to general SSTV route to prevent conflicts.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Adds a phosphor-persistence waveform scope showing audio RMS/peak
levels during ISS SSTV and General SSTV decoding, matching the
existing pager scope pattern with a purple color scheme.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Users can now manage decoded SSTV images with download and delete actions
accessible from hover overlays on gallery cards, the full-size image modal
toolbar, and a "Clear All" button in the gallery header. Both ISS and
General SSTV modes are supported.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
slowrx is a GTK GUI app that doesn't support CLI usage, so the SSTV
decoder was silently failing. This replaces it with a pure Python
implementation using numpy and Pillow that supports Robot36/72,
Martin1/2, Scottie1/2, and PD120/180 modes via VIS header auto-detection.
Key implementation details:
- Generalized Goertzel (DTFT) for exact-frequency tone detection
- Vectorized batch Goertzel for real-time pixel decoding performance
- Overlapping analysis windows for short-window frequency estimation
- VIS header detection state machine with parity validation
- Per-line sync re-synchronization for drift tolerance
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Adds a general-purpose SSTV decoder alongside the existing ISS SSTV mode,
supporting USB/LSB/FM modulation on common amateur radio HF/VHF/UHF
frequencies (14.230 MHz USB, 3.845 MHz LSB, etc.) with auto-detection
of modulation from preset frequency table.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
