X-Git-Url: http://git.kpe.io/?a=blobdiff_plain;f=wdq2wav.cpp;h=ddf75843c78813d9047aa4a94b7ddd34b84c84eb;hb=edcd5b449b8711db8e447e1d8bb8ddf3866e7b62;hp=60e58421c9a60554674abc11df48f2987b98d085;hpb=746abe47c4eaefae0023dde9a8938b80bfcb8247;p=wdq2wav.git

diff --git a/wdq2wav.cpp b/wdq2wav.cpp
index 60e5842..ddf7584 100644
--- a/wdq2wav.cpp
+++ b/wdq2wav.cpp
@@ -8,7 +8,7 @@
 **
 **  Copyright (c) 2003 Kevin Rosenberg
 **
-**  $Id: wdq2wav.cpp,v 1.19 2003/02/24 12:53:46 kevin Exp $
+**  $Id: wdq2wav.cpp,v 1.26 2003/02/28 04:12:17 kevin Exp $
 **
 **  This program is free software; you can redistribute it and/or modify
 **  it under the terms of the GNU General Public License (version 2) as
@@ -26,12 +26,13 @@
 
 #include <wdq2wav.h>
 
-const char* g_szIdStr = "$Id: wdq2wav.cpp,v 1.19 2003/02/24 12:53:46 kevin Exp $";
+const char* g_szIdStr = "$Id: wdq2wav.cpp,v 1.26 2003/02/28 04:12:17 kevin Exp $";
 
 bool g_quiet = false;
 bool g_verbose = false;
 bool g_debug = false;
-bool g_ignore_zero = false;
+bool g_preserve_zero = false;
+bool g_demean = false;
 
 
 #ifdef WIN32
@@ -110,7 +111,9 @@ usage (const char* progname)
   std::cout << "OPTIONS\n";
   std::cout << "  -p   Play channel through audio system\n";
   std::cout << "  -q   Supress all messages\n";
-  std::cout << "  -z   Scale output without regard for windaq zero point\n";
+  std::cout << "  -z   Scale output with preserving zero point\n";
+  std::cout << "  -m   Demean the data (subtract the mean value from each sample)\n";
+  std::cout << "       [Selecting this option automatically sets the -z option]\n";
   std::cout << "  -v   Verbose mode\n";
   std::cout << "  -d   Debug mode\n";
   std::cout << "  -r   Print program version\n";
@@ -126,7 +129,7 @@ main (int argc, char *argv[])
 
   const char* progname = argv[0];
   
-  while ((c = getopt (argc, argv, "rqvzdph")) != -1) {
+  while ((c = getopt (argc, argv, "rqvzmdph")) != -1) {
     switch (c) {
     case 'r':
         std::cout << "Version " << g_szIdStr << std::endl;
@@ -134,6 +137,13 @@ main (int argc, char *argv[])
     case 'q':
       g_quiet = true;
       break;
+    case 'm':
+      g_demean = true;
+      g_preserve_zero = true; // auto set
+      break;
+    case 'z':
+      g_preserve_zero = true;
+      break;
     case 'v':
       g_verbose = true;
       break;
@@ -143,9 +153,6 @@ main (int argc, char *argv[])
     case 'p':
       play = true;
       break;
-    case 'z':
-      g_ignore_zero = true;
-      break;
     case 'h':
       usage (progname);
       return (0);
@@ -434,6 +441,7 @@ bool get_float8 (int fd, double& f)
   return true;
 }
 
+
 bool
 WindaqChannel::read_channel_data ()
 {
@@ -458,7 +466,7 @@ WindaqChannel::read_channel_data ()
   }
   m_units = units;
  
-  unsigned int row_bytes = 2 * r_wdq.m_nChannels;
+  long int row_bytes = 2 * r_wdq.m_nChannels;
   signed short int *sample_row = new signed short int [row_bytes];
   
   signed short int* psample = &sample_row[m_channel - 1];
@@ -466,6 +474,7 @@ WindaqChannel::read_channel_data ()
   lseek (fd, r_wdq.m_nHeader_bytes, SEEK_SET);
   unsigned long int i;
   signed short int data_max = 0, data_min = 0;
+  double total_data = 0;
   for (i = 0; i < r_wdq.m_nSamples; i++) {
     if (read (fd, sample_row, row_bytes) != row_bytes) {
       std::ostringstream os;
@@ -483,6 +492,7 @@ WindaqChannel::read_channel_data ()
 
     signed short int value = v >> 2;
     m_data[i] = value;
+    total_data += value;
     
     if (i == 0) {
       data_max = value;
@@ -500,6 +510,16 @@ WindaqChannel::read_channel_data ()
   m_max_scaled_data = (m_slope * data_max) + m_intercept;
   m_min_scaled_data = (m_slope * data_min) + m_intercept;
 
+  if (g_demean) {
+    double dmean = total_data / static_cast<double>(r_wdq.m_nSamples);
+    int mean = nearest<int>(dmean);
+    std::cout << "Removing mean: " << (dmean * m_slope) + m_intercept <<
+      " " << m_units << std::endl;
+    
+    for (i = 0; i < r_wdq.m_nSamples; i++)
+      m_data[i] -= mean;
+  }
+  
   delete sample_row;
   return true;
 }
@@ -516,17 +536,17 @@ WavFile::WavFile (WindaqChannel& wdq_channel, const char* fname)
     m_rate = wdq_channel.r_wdq.m_sample_rate;
 
     double data_offset = 0, data_scale = 0;
-    if (g_ignore_zero) {
-      data_offset = -wdq_channel.m_min_scaled_data;
-      if (wdq_channel.m_max_scaled_data != wdq_channel.m_min_scaled_data)
-	data_scale = 65535. / (wdq_channel.m_max_scaled_data -
-			       wdq_channel.m_min_scaled_data);
-    } else {
+    if (g_preserve_zero) {
       double max_value = fabs(wdq_channel.m_max_scaled_data);
       if (fabs (wdq_channel.m_min_scaled_data) > max_value)
 	max_value = fabs (wdq_channel.m_min_scaled_data);
       if (max_value != 0.)
 	data_scale = 32767. / max_value;
+    } else {
+      data_offset = -wdq_channel.m_min_scaled_data;
+      if (wdq_channel.m_max_scaled_data != wdq_channel.m_min_scaled_data)
+	data_scale = 65535. / (wdq_channel.m_max_scaled_data -
+			       wdq_channel.m_min_scaled_data);
     }
     
     if (g_debug) {
@@ -554,11 +574,12 @@ WavFile::WavFile (WindaqChannel& wdq_channel, const char* fname)
     for (i = 0; i < m_nSamples; i++) {
       double value = input[i];
       value = (slope * value) + intercept;
-      if (g_ignore_zero) {
+      if (g_preserve_zero) {
+	value = value * data_scale;
+      } else {
 	value = (value + data_offset) * data_scale;
 	value += 0.5 - 32768;
-      } else
-	value = value * data_scale;
+      }
       
       signed short int v = static_cast<signed short int>(value);
 #if WORDS_BIG_ENDIAN
@@ -696,7 +717,7 @@ WavFile::Play ()
     close(fd); return false;
   }
   
-  int channels = m_nChannels;
+  unsigned int channels = m_nChannels;
   if (ioctl (fd, SNDCTL_DSP_CHANNELS, &format) == -1) {
     error_msg ("Error setting number of channels");
     close(fd); return false;