Hotfix bdf recording (#445)

* change depricated function

* Flush EDF buffer at quarter-second intervals

Reduce the threshold for writing EDF samples from _fs to _fs // 4 so buffered data is flushed more frequently. Previously the FileRecorder only wrote when the buffer exceeded one second of samples; this change triggers writes at roughly quarter-second increments to lower memory usage and latency while retaining the existing behavior of writing full _fs-sized chunks and updating annotations/timestamps under the same lock.

* Write full-second sample blocks to file

Replace the previous arbitrary threshold write logic with computation of whole-second sample blocks: compute num_samples_to_write as (n_samples // fs) * fs and only write when > 0. This ensures written chunks are multiples of the sampling frequency, avoids partial-frame writes and potential timestamp/data misalignment, and then drops the written samples from the buffer.

Author: salman2135

src/explorepy/tools.py

@@ -362,10 +362,11 @@ def _write_edf(self, packet):
         self._data = np.concatenate((self._data, data), axis=1)
         self._timestamps += list(data[0, :])
         with lock:
-            if self._data.shape[1] > self._fs // 4:
-                self._file_obj.writeSamples(list(self._data[:, :self._fs]))
+            num_samples_to_write = (self._data.shape[1] // self._fs) * self._fs
+            if num_samples_to_write > 0:
+                self._file_obj.writeSamples(list(self._data[:, :num_samples_to_write]))
                 self._write_edf_anno()
-                self._data = self._data[:, self._fs:]
+                self._data = self._data[:, num_samples_to_write:]
 
     def _process_packet_data(self, packet):
         """Helper function to extract and format data from a packet."""