From 28aaff6c99da4d035b14dde522aeb64bfb944e63 Mon Sep 17 00:00:00 2001
From: oparviai <oparviai@f3a24b6a-cf45-0410-b55a-8c22e2698227>
Date: Thu, 12 Feb 2009 17:22:06 +0000
Subject: [PATCH] Fixed buffer overflow bug in BPMDetect.cpp & changed version
 to 1.4.1

---
 README.html                     |  9 ++++++-
 include/SoundTouch.h            |  4 +--
 source/SoundStretch/main.cpp    |  1 +
 source/SoundTouch/BPMDetect.cpp | 44 +++++++++++++++++++--------------
 4 files changed, 37 insertions(+), 21 deletions(-)
diff --git a/README.html b/README.html
index 782429b..9a5afb2 100644
--- a/README.html
+++ b/README.html
@@ -18,7 +18,7 @@
 </head>
 <body class="normal">
 <hr>
-<h1>SoundTouch audio processing library v1.4.0
+<h1>SoundTouch audio processing library v1.4.1
 </h1>
 <p class="normal">SoundTouch library Copyright (c) Olli
 Parviainen 2002-2009 </p>
@@ -538,6 +538,13 @@ estimates the BPM rate:</p>
 <h2>5. Change History</h2>
 <h3>5.1. SoundTouch library Change History </h3>
 
+<p><strong>1.4.1:</strong></p>
+<ul>
+<li>Fixed a buffer overflow bug in BPM detect algorithm routines if processing
+  more than 2048 samples at one call&nbsp;</li>
+
+</ul>
+
 <p><strong>1.4.0:</strong></p>
 <ul>
 <li>Improved sound quality by automatic calculation of time stretch algorithm
diff --git a/include/SoundTouch.h b/include/SoundTouch.h
index f9ea26b..8a5d2ac 100644
--- a/include/SoundTouch.h
+++ b/include/SoundTouch.h
@@ -79,10 +79,10 @@ namespace soundtouch
 {
 
 /// Soundtouch library version string
-#define SOUNDTOUCH_VERSION          "1.4.0"
+#define SOUNDTOUCH_VERSION          "1.4.1"
 
 /// SoundTouch library version id
-#define SOUNDTOUCH_VERSION_ID       (10400)
+#define SOUNDTOUCH_VERSION_ID       (10401)
 
 //
 // Available setting IDs for the 'setSetting' & 'get_setting' functions:
diff --git a/source/SoundStretch/main.cpp b/source/SoundStretch/main.cpp
index 559d881..3ad8619 100644
--- a/source/SoundStretch/main.cpp
+++ b/source/SoundStretch/main.cpp
@@ -229,6 +229,7 @@ static void detectBPM(WavInFile *inFile, RunParameters *params)
     fflush(stderr);
 
     nChannels = inFile->getNumChannels();
+    assert(BUFF_SIZE % nChannels == 0);
 
     // Process the 'inFile' in small blocks, repeat until whole file has 
     // been processed
diff --git a/source/SoundTouch/BPMDetect.cpp b/source/SoundTouch/BPMDetect.cpp
index 972cd4c..b98b720 100644
--- a/source/SoundTouch/BPMDetect.cpp
+++ b/source/SoundTouch/BPMDetect.cpp
@@ -115,7 +115,8 @@ BPMDetect::~BPMDetect()
 }
 
 
-/// low-pass filter & decimate to about 500 Hz. return number of outputted samples.
+/// convert to mono, low-pass filter & decimate to about 500 Hz. 
+/// return number of outputted samples.
 ///
 /// Decimation is used to remove the unnecessary frequencies and thus to reduce 
 /// the amount of data needed to be processed as calculating autocorrelation 
@@ -134,13 +135,20 @@ int BPMDetect::decimate(SAMPLETYPE *dest, const SAMPLETYPE *src, int numsamples)
     outcount = 0;
     for (count = 0; count < numsamples; count ++) 
     {
-        decimateSum += src[count];
+        int j;
+
+        // convert to mono and accumulate
+        for (j = 0; j < channels; j ++)
+        {
+            decimateSum += src[j];
+        }
+        src += j;
 
         decimateCount ++;
         if (decimateCount >= decimateBy) 
         {
             // Store every Nth sample only
-            out = (LONG_SAMPLETYPE)(decimateSum / decimateBy);
+            out = (LONG_SAMPLETYPE)(decimateSum / (decimateBy * channels));
             decimateSum = 0;
             decimateCount = 0;
 #ifdef INTEGER_SAMPLES
@@ -231,27 +239,27 @@ void BPMDetect::calcEnvelope(SAMPLETYPE *samples, int numsamples)
 
 
 
-void BPMDetect::inputSamples(SAMPLETYPE *samples, int numSamples)
+void BPMDetect::inputSamples(const SAMPLETYPE *samples, int numSamples)
 {
     SAMPLETYPE decimated[DECIMATED_BLOCK_SAMPLES];
 
-    // convert from stereo to mono if necessary
-    if (channels == 2)
+    // iterate so that max INPUT_BLOCK_SAMPLES processed per iteration
+    while (numSamples > 0)
     {
-        int i;
+        int block;
+        int decSamples;
 
-        for (i = 0; i < numSamples; i ++)
-        {
-            samples[i] = (samples[i * 2] + samples[i * 2 + 1]) / 2;
-        }
+        block = (numSamples > INPUT_BLOCK_SAMPLES) ? INPUT_BLOCK_SAMPLES : numSamples;
+
+        // decimate. note that converts to mono at the same time
+        decSamples = decimate(decimated, samples, block);
+        samples += block * channels;
+        numSamples -= block;
+
+        // envelope new samples and add them to buffer
+        calcEnvelope(decimated, decSamples);
+        buffer->putSamples(decimated, decSamples);
     }
-    
-    // decimate
-    numSamples = decimate(decimated, samples, numSamples);
-
-    // envelope new samples and add them to buffer
-    calcEnvelope(decimated, numSamples);
-    buffer->putSamples(decimated, numSamples);
 
     // when the buffer has enought samples for processing...
     if ((int)buffer->numSamples() > windowLen) 
