cmake minimum version to 3.5 to avoid deprecation warning

Refactor pow() usage:
- use base of 0.5^k instead of 1/(2^k)
- skip pow if using INTEGER_SAMPLES

CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 3.1)
+cmake_minimum_required(VERSION 3.5)
 project(SoundTouch VERSION 2.3.3 LANGUAGES CXX)
 set(CMAKE_CXX_STANDARD 17)
 
@@ -13,7 +13,8 @@ else()
   if(EMSCRIPTEN)
     list(APPEND COMPILE_OPTIONS -O3)
   else()
-    list(APPEND COMPILE_OPTIONS -Ofast)
+    # Apply -ffast-math to allow compiler autovectorization generate effective SIMD code for arm compilation
+    list(APPEND COMPILE_OPTIONS -O3 -ffast-math)
   endif()
 endif()
 
@@ -96,6 +97,7 @@ install(
     include/soundtouch_config.h
   DESTINATION
     "${CMAKE_INSTALL_INCLUDEDIR}/soundtouch"
+  COMPONENT SoundTouch
 )
 
 install(TARGETS SoundTouch
@@ -104,6 +106,7 @@ install(TARGETS SoundTouch
   LIBRARY DESTINATION "${CMAKE_INSTALL_LIBDIR}"
   RUNTIME DESTINATION "${CMAKE_INSTALL_BINDIR}"
   INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}"
+  COMPONENT SoundTouch
 )
 
 #######################
@@ -126,6 +129,7 @@ if(SOUNDSTRETCH)
 
   install(TARGETS soundstretch
     DESTINATION bin
+    COMPONENT soundstretch
   )
 endif()
 
@@ -144,8 +148,8 @@ if(SOUNDTOUCH_DLL)
   target_compile_definitions(SoundTouchDLL PRIVATE DLL_EXPORTS)
   target_include_directories(SoundTouchDLL PUBLIC $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/include>)
   target_link_libraries(SoundTouchDLL PRIVATE SoundTouch)
-  install(FILES source/SoundTouchDLL/SoundTouchDLL.h DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/soundtouch")
-  install(TARGETS SoundTouchDLL EXPORT SoundTouchTargets)
+  install(FILES source/SoundTouchDLL/SoundTouchDLL.h DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}/soundtouch" COMPONENT SoundTouchDLL)
+  install(TARGETS SoundTouchDLL EXPORT SoundTouchTargets COMPONENT SoundTouchDLL)
 endif()
 
 ########################
@@ -157,7 +161,7 @@ set(libdir "\${prefix}/${CMAKE_INSTALL_LIBDIR}")
 set(includedir "\${prefix}/${CMAKE_INSTALL_INCLUDEDIR}")
 set(VERSION "${CMAKE_PROJECT_VERSION}")
 configure_file(soundtouch.pc.in "${CMAKE_CURRENT_BINARY_DIR}/soundtouch.pc" @ONLY)
-install(FILES "${CMAKE_CURRENT_BINARY_DIR}/soundtouch.pc" DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig")
+install(FILES "${CMAKE_CURRENT_BINARY_DIR}/soundtouch.pc" DESTINATION "${CMAKE_INSTALL_LIBDIR}/pkgconfig" COMPONENT SoundTouch)
 
 # CMake config
 include(CMakePackageConfigHelpers)
@@ -167,6 +171,7 @@ install(
   FILE SoundTouchTargets.cmake
   NAMESPACE SoundTouch::
   DESTINATION "${SOUNDTOUCH_INSTALL_CMAKEDIR}"
+  COMPONENT SoundTouch
 )
 configure_package_config_file(SoundTouchConfig.cmake.in
   "${CMAKE_CURRENT_BINARY_DIR}/SoundTouchConfig.cmake"
@@ -182,4 +187,5 @@ install(
     "${CMAKE_CURRENT_BINARY_DIR}/SoundTouchConfig.cmake"
     "${CMAKE_CURRENT_BINARY_DIR}/SoundTouchConfigVersion.cmake"
   DESTINATION "${SOUNDTOUCH_INSTALL_CMAKEDIR}"
+  COMPONENT SoundTouch
 )

README.html

@@ -205,7 +205,7 @@
       separate mono channels, this isn't recommended because processing the
       channels separately would result in losing the phase coherency between
       the channels, which consequently would ruin the stereo effect.</p>
-    <p>Sample rates between 8000-48000H are supported.</p>
+    <p>Sample rates between 8000-48000Hz are supported.</p>
     <h3>3.2. Processing latency</h3>
     <p>The processing and latency constraints of the SoundTouch library are:</p>
     <ul>

configure.ac

@@ -31,9 +31,8 @@ AC_DISABLE_STATIC	dnl This makes libtool only build shared libs
 
 AC_LANG(C++)
 
-# Compiler flags. Apply -Ofast (implies -O3 -ffast-math) to allow gcc autovectorization
-# generate effective SIMD code.
-CXXFLAGS="${CXXFLAGS} -Ofast -Wall -Wextra -Wzero-as-null-pointer-constant -Wno-unknown-pragmas"
+# Compiler flags. Apply -ffast-math to allow compiler autovectorization generate effective SIMD code for arm compilation
+CXXFLAGS="${CXXFLAGS} -O3 -ffast-math -Wall -Wextra -Wzero-as-null-pointer-constant -Wno-unknown-pragmas"
 
 # Set AR_FLAGS to avoid build warning "ar: `u' modifier ignored since `D' is the default (see `U')"
 AR_FLAGS='cr'

include/STTypes.h

@@ -56,8 +56,9 @@ typedef unsigned long   ulong;
 
 namespace soundtouch
 {
-    /// Max allowed number of channels
-    #define SOUNDTOUCH_MAX_CHANNELS     16
+    /// Max allowed number of channels. This is not a hard limit but to have some
+    /// maximum value for argument sanity checks -- can be increased if necessary
+    #define SOUNDTOUCH_MAX_CHANNELS     32
 
     /// Activate these undef's to overrule the possible sampletype
     /// setting inherited from some other header file:

source/SoundStretch/RunParameters.cpp

@@ -199,7 +199,7 @@ void RunParameters::throwLicense() const
     ST_THROW_RT_ERROR(licenseText);
 }
 
-float RunParameters::parseSwitchValue(const STRING& str) const
+double RunParameters::parseSwitchValue(const STRING& str) const
 {
     int pos;
 
@@ -211,7 +211,7 @@ float RunParameters::parseSwitchValue(const STRING& str) const
     }
 
     // Read numerical parameter value after '='
-    return (float)stof(str.substr(pos + 1).c_str());
+    return stof(str.substr(pos + 1).c_str());
 }
 
 

source/SoundStretch/RunParameters.h

@@ -48,17 +48,17 @@ private:
     void throwLicense() const;
     void parseSwitchParam(const STRING& str);
     void checkLimits();
-    float parseSwitchValue(const STRING& tr) const;
+    double parseSwitchValue(const STRING& tr) const;
 
 public:
     STRING inFileName;
     STRING outFileName;
-    float tempoDelta{ 0 };
-    float pitchDelta{ 0 };
-    float rateDelta{ 0 };
+    double tempoDelta{ 0 };
+    double pitchDelta{ 0 };
+    double rateDelta{ 0 };
     int   quick{ 0 };
     int   noAntiAlias{ 0 };
-    float goalBPM{ 0 };
+    double goalBPM{ 0 };
     bool  detectBPM{ false };
     bool  speech{ false };
 

source/SoundStretch/main.cpp

@@ -145,9 +145,9 @@ static void setup(SoundTouch& soundTouch, const WavInFile& inFile, const RunPara
 #endif
         // print processing information only if outFileName given i.e. some processing will happen
         fprintf(stderr, "Processing the file with the following changes:\n");
-        fprintf(stderr, "  tempo change = %+g %%\n", params.tempoDelta);
-        fprintf(stderr, "  pitch change = %+g semitones\n", params.pitchDelta);
-        fprintf(stderr, "  rate change  = %+g %%\n\n", params.rateDelta);
+        fprintf(stderr, "  tempo change = %+lg %%\n", params.tempoDelta);
+        fprintf(stderr, "  pitch change = %+lg semitones\n", params.pitchDelta);
+        fprintf(stderr, "  rate change  = %+lg %%\n\n", params.rateDelta);
         fprintf(stderr, "Working...");
     }
     else
@@ -240,7 +240,7 @@ static void detectBPM(WavInFile& inFile, RunParameters& params)
 
     if (bpmValue > 0)
     {
-        fprintf(stderr, "Detected BPM rate %.1f\n\n", bpmValue);
+        fprintf(stderr, "Detected BPM rate %.1lf\n\n", bpmValue);
     }
     else
     {
@@ -252,7 +252,7 @@ static void detectBPM(WavInFile& inFile, RunParameters& params)
     {
         // adjust tempo to given bpm
         params.tempoDelta = (params.goalBPM / bpmValue - 1.0f) * 100.0f;
-        fprintf(stderr, "The file will be converted to %.1f BPM\n\n", params.goalBPM);
+        fprintf(stderr, "The file will be converted to %.1lf BPM\n\n", params.goalBPM);
     }
 }
 

source/SoundTouch/BPMDetect.cpp

@@ -301,7 +301,7 @@ void BPMDetect::updateXCorr(int process_samples)
     pBuffer = buffer->ptrBegin();
 
     // calculate decay factor for xcorr filtering
-    float xcorr_decay = (float)pow(0.5, 1.0 / (XCORR_DECAY_TIME_CONSTANT * TARGET_SRATE / process_samples));
+    float xcorr_decay = (float)pow(0.5, process_samples / (XCORR_DECAY_TIME_CONSTANT * TARGET_SRATE));
 
     // prescale pbuffer
     float tmp[XCORR_UPDATE_SEQUENCE];

source/SoundTouch/FIRFilter.cpp

@@ -56,7 +56,6 @@ using namespace soundtouch;
 FIRFilter::FIRFilter()
 {
     resultDivFactor = 0;
-    resultDivider = 0;
     length = 0;
     lengthDiv8 = 0;
     filterCoeffs = nullptr;
@@ -155,7 +154,7 @@ uint FIRFilter::evaluateFilterMulti(SAMPLETYPE *dest, const SAMPLETYPE *src, uin
     assert(src != nullptr);
     assert(dest != nullptr);
     assert(filterCoeffs != nullptr);
-    assert(numChannels < 16);
+    assert(numChannels <= SOUNDTOUCH_MAX_CHANNELS);
 
     // hint compiler autovectorization that loop length is divisible by 8
     int ilength = length & -8;
@@ -207,24 +206,24 @@ void FIRFilter::setCoefficients(const SAMPLETYPE *coeffs, uint newLength, uint u
     assert(newLength > 0);
     if (newLength % 8) ST_THROW_RT_ERROR("FIR filter length not divisible by 8");
 
-    #ifdef SOUNDTOUCH_FLOAT_SAMPLES
-        // scale coefficients already here if using floating samples
-        double scale = 1.0 / resultDivider;
-    #else
-        short scale = 1;
-    #endif
-
     lengthDiv8 = newLength / 8;
     length = lengthDiv8 * 8;
     assert(length == newLength);
 
     resultDivFactor = uResultDivFactor;
-    resultDivider = (SAMPLETYPE)::pow(2.0, (int)resultDivFactor);
 
     delete[] filterCoeffs;
     filterCoeffs = new SAMPLETYPE[length];
     delete[] filterCoeffsStereo;
     filterCoeffsStereo = new SAMPLETYPE[length*2];
+
+#ifdef SOUNDTOUCH_FLOAT_SAMPLES
+    // scale coefficients already here if using floating samples
+    const double scale = ::pow(0.5, (int)resultDivFactor);;
+#else
+    const short scale = 1;
+#endif
+
     for (uint i = 0; i < length; i ++)
     {
         filterCoeffs[i] = (SAMPLETYPE)(coeffs[i] * scale);

source/SoundTouch/FIRFilter.h

@@ -52,9 +52,6 @@ protected:
     // Result divider factor in 2^k format
     uint resultDivFactor;
 
-    // Result divider value.
-    SAMPLETYPE resultDivider;
-
     // Memory for filter coefficients
     SAMPLETYPE *filterCoeffs;
     SAMPLETYPE *filterCoeffsStereo;

source/SoundTouch/sse_optimized.cpp

@@ -211,9 +211,6 @@ FIRFilterSSE::~FIRFilterSSE()
 // (overloaded) Calculates filter coefficients for SSE routine
 void FIRFilterSSE::setCoefficients(const float *coeffs, uint newLength, uint uResultDivFactor)
 {
-    uint i;
-    float fDivider;
-
     FIRFilter::setCoefficients(coeffs, newLength, uResultDivFactor);
 
     // Scale the filter coefficients so that it won't be necessary to scale the filtering result
@@ -223,13 +220,13 @@ void FIRFilterSSE::setCoefficients(const float *coeffs, uint newLength, uint uRe
     filterCoeffsUnalign = new float[2 * newLength + 4];
     filterCoeffsAlign = (float *)SOUNDTOUCH_ALIGN_POINTER_16(filterCoeffsUnalign);
 
-    fDivider = (float)resultDivider;
+    const float scale = ::pow(0.5, (int)resultDivFactor);
 
-    // rearrange the filter coefficients for mmx routines
-    for (i = 0; i < newLength; i ++)
+    // rearrange the filter coefficients for sse routines
+    for (auto i = 0U; i < newLength; i ++)
     {
         filterCoeffsAlign[2 * i + 0] =
-        filterCoeffsAlign[2 * i + 1] = coeffs[i + 0] / fDivider;
+        filterCoeffsAlign[2 * i + 1] = coeffs[i] * scale;
     }
 }