Implement row-averaged FFT feature for same-row SNR cleanup

Add row-averaged FFT feature with configurable window size (row_avg_n parameter) for improved signal-to-noise ratio on noisy scans. Includes: - Gaussian-weighted same-row neighbor averaging (never crosses rows) - Masked/renormalized convolution handling for edge cases and masked samples - Cache format v2 with row_avg_n tracking to prevent silent cache mismatches - GUI dialog option for row-average window configuration - Comprehensive tests validating kernel properties, background subtraction invariance, and cache dispatch Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>
2026-08-07 21:50:05 -05:00
parent eecb0e3a82
commit 3989c2a1b8
10 changed files with 1363 additions and 51 deletions
@@ -152,6 +152,105 @@ class FftOptionsDialog(QDialog):
        return max(1, self._spin_pad.value())


+# ---------------------------------------------------------------------------
+# Row-Averaged FFT Options dialog
+# ---------------------------------------------------------------------------
+
+class RowAverageFftOptionsDialog(QDialog):
+    """Configure the same-row, distance-weighted neighbor averaging applied
+    to each pixel's CH1 waveform before 'Batch Compute Row-Averaged FFT and
+    Store' re-runs the FFT peak search — a same-row SNR cleanup pass, never
+    mixing across rows/Y (see sras_compute._row_average_waveforms).
+
+    Unlike the plain FFT batch action (which stores unmasked and defers
+    masking to display time), the DC threshold here is required up front:
+    it decides which same-row neighbors are eligible to contribute to a
+    pixel's average, so it can't be deferred.
+
+    Changes take effect only when the user clicks Apply. Cancel discards
+    all pending edits.
+    """
+
+    def __init__(self, parent=None, *,
+                 current_n: int,
+                 current_threshold_mv: float,
+                 pixel_x_mm: float | None):
+        super().__init__(parent)
+        self.setWindowTitle("Row-Averaged FFT Options")
+        self.setModal(True)
+        self.setMinimumWidth(380)
+
+        self._pixel_x_mm = pixel_x_mm
+
+        layout = QVBoxLayout(self)
+
+        # ---- Neighbor window ---------------------------------------------
+        grp_window = QGroupBox("Same-Row Neighbor Window")
+        wl = QVBoxLayout(grp_window)
+
+        n_row = QHBoxLayout()
+        n_row.addWidget(QLabel("Neighbor half-width (n):"))
+        self._spin_n = QSpinBox()
+        self._spin_n.setRange(1, 50)
+        self._spin_n.setValue(max(1, current_n))
+        self._spin_n.setToolTip(
+            "Each pixel's CH1 waveform is averaged with up to n same-row\n"
+            "neighbors on each side, distance-weighted (Gaussian) and\n"
+            "counting only neighbors that already pass the DC threshold\n"
+            "below. Never mixes across rows/Y.")
+        self._spin_n.valueChanged.connect(self._update_info)
+        n_row.addWidget(self._spin_n)
+        wl.addLayout(n_row)
+
+        self._lbl_width = QLabel()
+        self._lbl_width.setStyleSheet(_CSS_HINT)
+        wl.addWidget(self._lbl_width)
+
+        layout.addWidget(grp_window)
+
+        # ---- DC threshold ------------------------------------------------
+        grp_thr = QGroupBox("Neighbor Validity")
+        tl = QVBoxLayout(grp_thr)
+        thr_row = QHBoxLayout()
+        thr_row.addWidget(QLabel("DC threshold:"))
+        self._spin_threshold = _make_dspin(-500.0, 500.0, 3, suffix=" mV",
+                                           value=current_threshold_mv, step=0.025)
+        self._spin_threshold.setToolTip(
+            "A same-row neighbor only contributes to a pixel's average if\n"
+            "its own CH4 signal is at or above this threshold -- the same\n"
+            "test used for RF mask display. A pixel below threshold stays\n"
+            "masked, exactly as today; it is never rescued by its neighbors.")
+        thr_row.addWidget(self._spin_threshold)
+        tl.addLayout(thr_row)
+        layout.addWidget(grp_thr)
+
+        # ---- Buttons -----------------------------------------------------
+        buttons = QDialogButtonBox()
+        buttons.addButton("Apply", QDialogButtonBox.ButtonRole.AcceptRole
+                          ).clicked.connect(self.accept)
+        buttons.addButton("Cancel", QDialogButtonBox.ButtonRole.RejectRole
+                          ).clicked.connect(self.reject)
+        layout.addWidget(buttons)
+
+        self._update_info()
+
+    def _update_info(self):
+        n = self._spin_n.value()
+        if self._pixel_x_mm is None:
+            self._lbl_width.setText("Load a file to preview the window's physical width.")
+            return
+        width_um = 2 * n * self._pixel_x_mm * 1e3
+        self._lbl_width.setText(
+            f"Window: ±{n} px = {width_um:.2f} µm full width "
+            f"(pixel pitch {self._pixel_x_mm * 1e3:.3g} µm)")
+
+    def get_half_width(self) -> int:
+        return self._spin_n.value()
+
+    def get_threshold_mv(self) -> float:
+        return self._spin_threshold.value()
+
+

 class ManualAlignmentDialog(QDialog):
    """Non-modal manual angle-alignment editor (Fusion -> Manual Alignment...).