Use fftconvolve

src/calng/correction_addons/autocorrelation.py

@@ -44,14 +44,14 @@ class Autocorrelation(BaseCorrectionAddon):
     def post_correction(self, processed_data, cell_table, pulse_table, output_hash):
         """Called directly after correction has happened. Processed data will still be
         on GPU if the correction device is generally running in GPU mode."""
+        from cupyx.scipy.signal import fftconvolve
 
         data = processed_data.copy()
         data[np.isnan(data)] = 0.0
 
-        # zero pad ???
-
-        g = np.fft.fft2(data)
-        autocorr_sum = np.fft.ifft2((g * g.conj()).sum(axis=0)).real
+        autocorr_sum = fftconvolve(
+            data, data[:, ::-1, ::-1], 'same', axes=(-2, -1)
+        ).sum(axis=0)
 
         frames_sum = data.sum(axis=0)