Smittix a397271553 fix: Slant correction via post-processing shear, not in-decoder sync fixup ...

Previous attempts to correct slant by altering R-channel placement and
buffer consumption caused cascading failures: a false positive in B pixel
data would misplace R, then the wrong consumed value misaligned the next
line's G, and the error compounded across all 256 lines.

New approach (safe by design):
- Sync search is measurement-only: never touches pos or consumed, so
  a noisy or wrong measurement cannot corrupt the current or future lines.
- Per-line deviation (measured sync position minus expected) is recorded
  in self._sync_deviations throughout the decode.
- get_image() fits a line through the deviations (linear regression) to
  estimate the per-line SDR clock drift rate, then applies a horizontal
  shear to the assembled PIL image: each row is shifted by
  -round(row × drift_rate × width / channel_samples) pixels.
- Worst case (all measurements fail): no correction applied, image
  quality identical to the pre-change baseline.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

2026-02-19 10:43:16 +00:00

..

__init__.py

Replace broken slowrx dependency with pure Python SSTV decoder

2026-02-06 19:47:02 +00:00

constants.py

fix: Correct SSTV VIS codes and replace Goertzel pixel decoder with Hilbert transform

2026-02-19 09:23:15 +00:00

dsp.py

Replace broken slowrx dependency with pure Python SSTV decoder

2026-02-06 19:47:02 +00:00

image_decoder.py

fix: Slant correction via post-processing shear, not in-decoder sync fixup

2026-02-19 10:43:16 +00:00

modes.py

fix: Correct SSTV VIS codes and replace Goertzel pixel decoder with Hilbert transform

2026-02-19 09:23:15 +00:00

sstv_decoder.py

fix: Add missing SSTV mode specs for HF decoding (PD90/PD160/PD240/ScottieDX)

2026-02-18 21:29:34 +00:00

vis.py

fix: Improve HF SSTV VIS detection reliability and error correction

2026-02-18 21:52:56 +00:00