From 99b855323590998b8eb335599d85f829a6429075 Mon Sep 17 00:00:00 2001
From: "J.A. de Jong - Redu-Sone B.V., ASCEE V.O.F" <j.a.dejong@ascee.nl>
Date: Thu, 29 Apr 2021 20:48:21 +0200
Subject: [PATCH] Bugfix in exportAsWave, with normalize

---
 lasp/lasp_measurement.py | 44 +++++++++++++++-------------------------
 1 file changed, 16 insertions(+), 28 deletions(-)

diff --git a/lasp/lasp_measurement.py b/lasp/lasp_measurement.py
index a44ba4d..1e86a24 100644
--- a/lasp/lasp_measurement.py
+++ b/lasp/lasp_measurement.py
@@ -96,6 +96,9 @@ class IterRawData:
 
         Args:
             f: Audio dataset in the h5 file, accessed as f['audio']
+            channels: list of channel indices to use
+            istart: index of first sample
+            istop: index of last sample (not including istop)
 
         """
         assert isinstance(channels, list)
@@ -173,22 +176,6 @@ class IterData(IterRawData):
         return scaleBlockSens(nextraw, self.sens)
 
 
-
-def exportAsWave(fn, fs, data, force=False):
-    if '.wav' not in fn[-4:]:
-        fn += '.wav'
-
-    nchannels = data.shape[1]
-    sampwidth = getSampWidth(data.dtype)
-
-    if os.path.exists(fn) and not force:
-        raise RuntimeError('File already exists: %s', fn)
-
-    with wave.open(fn, 'w') as wf:
-        wf.setparams((nchannels, sampwidth, fs, 0, 'NONE', 'NONE'))
-        wf.writeframes(np.asfortranarray(data).tobytes())
-
-
 class Measurement:
     """Provides access to measurement data stored in the h5 measurement file
     format."""
@@ -594,7 +581,7 @@ class Measurement:
 
 
     def exportAsWave(self, fn=None, force=False, newsampwidth=None,
-                     normalize=True, channels=None):
+                     normalize=True, **kwargs):
         """Export measurement file as wave. In case the measurement data is
         stored as floats, the values are scaled to the proper integer (PCM)
         data format.
@@ -626,20 +613,21 @@ class Measurement:
         if not np.isclose(self.samplerate%1,0):
             raise RuntimeError(f'Sample rates should be approximately integer for exporting to Wave to work')
 
-        # TODO: With VERY large files, this is not possible!
-        data = self.rawData()
-        if np.issubdtype(data.dtype, np.floating):
-            if newsampwidth is None:
-                raise ValueError('Newsampwidth parameter should be given for floating point raw data')
-
+        # TODO: With VERY large measurment files, this is not possible! Is this
+        # a theoretical case?
+        data = self.rawData(**kwargs)
+        if np.issubdtype(data.dtype, np.floating) and newsampwidth is None:
+            raise ValueError('Newsampwidth parameter should be given for floating point raw data')
 
         if normalize:
-            maxabs = np.max(np.abs(data), axis=0)
-            data /= maxabs[np.newaxis, :]
+            # Scale back to maximum of absolute value
+            maxabs = np.max(np.abs(data))
+            data /= maxabs
 
         if newsampwidth is not None:
             # Convert to floats, then to new sample width
-            data = scaleBlockSens(data, self.sensitivity**0)
+            sensone = np.ones_like(self.sensitivity)
+            data = scaleBlockSens(data, sensone)
 
             if newsampwidth == 2:
                 newtype = np.int16
@@ -648,11 +636,11 @@ class Measurement:
             else:
                 raise ValueError('Invalid sample width, should be 2 or 4')
 
-            scalefac = 2**(8*(newsampwidth-1))-1
+            scalefac = 2**(8*newsampwidth-1)-1
 
+            # Scale data to integer range, and then convert to integers
             data = (data*scalefac).astype(newtype)
 
-
         wavfile.write(fn, int(self.samplerate), data)
 
     @staticmethod