Added support for WAV file 'fact' chunk

README.html

@@ -507,6 +507,7 @@ and estimates the BPM rate:</p>
 <ul>
     <li>Replaced Windows-like 'BOOL' types with native 'bool'</li>
     <li>Fixed bug in Android.mk make file</li>
+    <li>Changed documentation token to "dist_doc_DATA" in Makefile.am file</li>
 </ul>
 <p><b>1.8.0:</b></p>
 <ul>
@@ -667,6 +668,11 @@ accessing the FIFOSampleBuffer class from external files. </li>
 </ul>
 <p>&nbsp;</p>
 <h3>5.2. SoundStretch application Change History </h3>
+<p><b>1.8.1:</b></p>
+<ul>
+    <li>Added support for WAV file 'fact' information chunk.</li>
+</ul>
+
 <p><b>1.7.0:</b></p>
 <ul>
     <li>Bugfixes in Wavfile: exception string formatting, avoid getLengthMs() integer 
@@ -750,6 +756,7 @@ submitted bugfixes since SoundTouch v1.3.1: </p>
   <li> Jason Garland</li>
   <li> Masa H.</li>
   <li> Takashi Iwai</li>
+  <li> Thomas Klausner</li>
   <li> Mathias Möhl</li>
   <li> Yuval Naveh</li>
   <li> Paulo Pizarro</li>

source/SoundStretch/WavFile.cpp

@@ -60,6 +60,7 @@ using namespace std;
 static const char riffStr[] = "RIFF";
 static const char waveStr[] = "WAVE";
 static const char fmtStr[]  = "fmt ";
+static const char factStr[] = "fact";
 static const char dataStr[] = "data";
 
 
@@ -558,6 +559,42 @@ int WavInFile::readHeaderBlock()
 
         return 0;
     }
+    else if (strcmp(label, factStr) == 0)
+    {
+        int nLen, nDump;
+
+        // 'fact' block 
+        memcpy(header.fact.fact_field, factStr, 4);
+
+        // read length of the fact field
+        if (fread(&nLen, sizeof(int), 1, fptr) != 1) return -1;
+        // swap byte order if necessary
+        _swap32(nLen); // int fact_len;
+        header.fact.fact_len = nLen;
+
+        // calculate how much length differs from expected
+        nDump = nLen - ((int)sizeof(header.fact) - 8);
+
+        // if format_len is larger than expected, read only as much data as we've space for
+        if (nDump > 0)
+        {
+            nLen = sizeof(header.fact) - 8;
+        }
+
+        // read data
+        if (fread(&(header.fact.fact_sample_len), nLen, 1, fptr) != 1) return -1;
+
+        // swap byte order if necessary
+        _swap32((int &)header.fact.fact_sample_len);    // int sample_length;
+
+        // if fact_len is larger than expected, skip the extra data
+        if (nDump > 0)
+        {
+            fseek(fptr, nDump, SEEK_CUR);
+        }
+
+        return 0;
+    }
     else if (strcmp(label, dataStr) == 0)
     {
         // 'data' block
@@ -642,6 +679,7 @@ uint WavInFile::getDataSizeInBytes() const
 uint WavInFile::getNumSamples() const
 {
     if (header.format.byte_per_sample == 0) return 0;
+    if (header.format.fixed > 1) return header.fact.fact_sample_len;
     return header.data.data_len / (unsigned short)header.format.byte_per_sample;
 }
 
@@ -739,6 +777,11 @@ void WavOutFile::fillInHeader(uint sampleRate, uint bits, uint channels)
     header.format.byte_rate = header.format.byte_per_sample * (int)sampleRate;
     header.format.sample_rate = (int)sampleRate;
 
+    // fill in the 'fact' part...
+    memcpy(&(header.fact.fact_field), factStr, 4);
+	header.fact.fact_len = 4;
+	header.fact.fact_sample_len = 0;
+
     // fill in the 'data' part..
 
     // copy string 'data' to data_field
@@ -751,8 +794,9 @@ void WavOutFile::fillInHeader(uint sampleRate, uint bits, uint channels)
 void WavOutFile::finishHeader()
 {
     // supplement the file length into the header structure
-    header.riff.package_len = bytesWritten + 36;
+    header.riff.package_len = bytesWritten + sizeof(WavHeader) - sizeof(WavRiff) + 4;
     header.data.data_len = bytesWritten;
+	header.fact.fact_sample_len = bytesWritten / header.format.byte_per_sample; 
 	
     writeHeader();
 }
@@ -775,6 +819,8 @@ void WavOutFile::writeHeader()
     _swap16((short &)hdrTemp.format.byte_per_sample);
     _swap16((short &)hdrTemp.format.bits_per_sample);
     _swap32((int &)hdrTemp.data.data_len);
+    _swap32((int &)hdrTemp.fact.fact_len);
+    _swap32((int &)hdrTemp.fact.fact_sample_len);
     
     // write the supplemented header in the beginning of the file
     fseek(fptr, 0, SEEK_SET);

source/SoundStretch/WavFile.h

@@ -75,6 +75,14 @@ typedef struct
     short bits_per_sample;
 } WavFormat;
 
+/// WAV audio file 'fact' section header
+typedef struct 
+{
+    char  fact_field[4];
+    int   fact_len;
+    uint  fact_sample_len;
+} WavFact;
+
 /// WAV audio file 'data' section header
 typedef struct 
 {
@@ -88,6 +96,7 @@ typedef struct
 {
     WavRiff   riff;
     WavFormat format;
+    WavFact   fact;
     WavData   data;
 } WavHeader;