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Replace aiffSampleRateTable unordered_map to ieee80 converter
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@alxarsenault
alxarsenault committed Oct 28, 2023
1 parent bcb61a4 commit df9538c
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112 changes: 63 additions & 49 deletions AudioFile.h
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Original file line number Diff line number Diff line change
Expand Up @@ -43,10 +43,10 @@
#include <string>
#include <cstring>
#include <fstream>
#include <unordered_map>
#include <iterator>
#include <algorithm>
#include <limits>
#include <cmath>

// disable some warnings on Windows
#if defined (_MSC_VER)
Expand Down Expand Up @@ -76,6 +76,9 @@ enum class AudioFileFormat
Aiff
};

template<typename U>
class AudioFileUnitTests;

//=============================================================
template <class T>
class AudioFile
Expand Down Expand Up @@ -203,8 +206,7 @@ class AudioFile
int getIndexOfChunk (std::vector<uint8_t>& source, const std::string& chunkHeaderID, int startIndex, Endianness endianness = Endianness::LittleEndian);

//=============================================================
uint32_t getAiffSampleRate (std::vector<uint8_t>& fileData, int sampleRateStartIndex);
bool tenByteMatch (std::vector<uint8_t>& v1, int startIndex1, std::vector<uint8_t>& v2, int startIndex2);
uint32_t getAiffSampleRate (const std::vector<uint8_t>& fileData, int sampleRateStartIndex);
void addSampleRateToAiffData (std::vector<uint8_t>& fileData, uint32_t sampleRate);

//=============================================================
Expand All @@ -223,6 +225,9 @@ class AudioFile
uint32_t sampleRate;
int bitDepth;
bool logErrorsToConsole {true};

template<typename U>
friend class AudioFileUnitTests;
};

//=============================================================
Expand Down Expand Up @@ -269,30 +274,6 @@ struct AudioSampleConverter
static T clamp (T v1, T minValue, T maxValue);
};

//=============================================================
// Pre-defined 10-byte representations of common sample rates
static std::unordered_map <uint32_t, std::vector<uint8_t>> aiffSampleRateTable = {
{8000, {64, 11, 250, 0, 0, 0, 0, 0, 0, 0}},
{11025, {64, 12, 172, 68, 0, 0, 0, 0, 0, 0}},
{16000, {64, 12, 250, 0, 0, 0, 0, 0, 0, 0}},
{22050, {64, 13, 172, 68, 0, 0, 0, 0, 0, 0}},
{32000, {64, 13, 250, 0, 0, 0, 0, 0, 0, 0}},
{37800, {64, 14, 147, 168, 0, 0, 0, 0, 0, 0}},
{44056, {64, 14, 172, 24, 0, 0, 0, 0, 0, 0}},
{44100, {64, 14, 172, 68, 0, 0, 0, 0, 0, 0}},
{47250, {64, 14, 184, 146, 0, 0, 0, 0, 0, 0}},
{48000, {64, 14, 187, 128, 0, 0, 0, 0, 0, 0}},
{50000, {64, 14, 195, 80, 0, 0, 0, 0, 0, 0}},
{50400, {64, 14, 196, 224, 0, 0, 0, 0, 0, 0}},
{88200, {64, 15, 172, 68, 0, 0, 0, 0, 0, 0}},
{96000, {64, 15, 187, 128, 0, 0, 0, 0, 0, 0}},
{176400, {64, 16, 172, 68, 0, 0, 0, 0, 0, 0}},
{192000, {64, 16, 187, 128, 0, 0, 0, 0, 0, 0}},
{352800, {64, 17, 172, 68, 0, 0, 0, 0, 0, 0}},
{2822400, {64, 20, 172, 68, 0, 0, 0, 0, 0, 0}},
{5644800, {64, 21, 172, 68, 0, 0, 0, 0, 0, 0}}
};

//=============================================================
enum WavAudioFormat
{
Expand Down Expand Up @@ -881,39 +862,72 @@ bool AudioFile<T>::decodeAiffFile (std::vector<uint8_t>& fileData)

//=============================================================
template <class T>
uint32_t AudioFile<T>::getAiffSampleRate (std::vector<uint8_t>& fileData, int sampleRateStartIndex)
uint32_t AudioFile<T>::getAiffSampleRate (const std::vector<uint8_t>& fileData, int sampleRateStartIndex)
{
for (auto it : aiffSampleRateTable)
{
if (tenByteMatch (fileData, sampleRateStartIndex, it.second, 0))
return it.first;
}
constexpr uint64_t ulTwoPow31 = 0x80000000UL;
constexpr double twoPow31 = 0x80000000UL;
constexpr double twoPowMinus63 = 1.0842021724855044e-19;
constexpr double twoPowMinus31 = 4.656612873077393e-10;

return 0;
}
const uint8_t* p = fileData.data() + sampleRateStartIndex;

//=============================================================
template <class T>
bool AudioFile<T>::tenByteMatch (std::vector<uint8_t>& v1, int startIndex1, std::vector<uint8_t>& v2, int startIndex2)
{
for (int i = 0; i < 10; i++)
const int16_t exp = ((p[0] << 8) | p[1]) & 0x7FFF;
p += 2;

uint64_t mant1 = *p++;
mant1 = (mant1 << 8) | *p++;
mant1 = (mant1 << 8) | *p++;
mant1 = (mant1 << 8) | *p++;

uint64_t mant0 = *p++;
mant0 = (mant0 << 8) | *p++;
mant0 = (mant0 << 8) | *p++;
mant0 = (mant0 << 8) | *p++;

if (mant1 == 0 && mant0 == 0 && exp == 0)
{
if (v1[startIndex1 + i] != v2[startIndex2 + i])
return false;
return 0;
}

return true;

const double m0 = mant0 & ulTwoPow31 ? double(twoPow31 + (mant0 & ~ulTwoPow31)) : double(mant0);
const double m1 = mant1 & ulTwoPow31 ? double(twoPow31 + (mant1 & ~ulTwoPow31)) : double(mant1);
return uint32_t((m0 * twoPowMinus63 + m1 * twoPowMinus31) * std::exp2(double(exp) - 16383.0));
}

//=============================================================
template <class T>
void AudioFile<T>::addSampleRateToAiffData (std::vector<uint8_t>& fileData, uint32_t sampleRate)
{
if (aiffSampleRateTable.count (sampleRate) > 0)
{
for (int i = 0; i < 10; i++)
fileData.push_back (aiffSampleRateTable[sampleRate][i]);
}
assert(sampleRate != 0 && "sample rate cannot be zero");

constexpr uint64_t ulTwoPow31 = 0x80000000UL;
constexpr double twoPow31 = 0x80000000UL;
constexpr double twoPow32 = 0x100000000UL;

double sr = sampleRate;

int16_t exp = int16_t(std::log2(sr) + 16383.0);
sr *= std::exp2(31.0 + 16383.0 - double(exp));

uint64_t mant1 = sr < twoPow31 ? uint64_t(sr) : ulTwoPow31 | uint64_t(sr - twoPow31);
const double m1 = (mant1 & ulTwoPow31) ? double(twoPow31 + (mant1 & (~ulTwoPow31))) : double(mant1);
sr = (sr - m1) * twoPow32;
uint64_t mant0 = sr < twoPow31 ? uint64_t(sr) : ulTwoPow31 | uint64_t(sr - twoPow31);

const size_t dataSize = fileData.size();
fileData.resize(dataSize + 10);
uint8_t* p = fileData.data() + dataSize;

*p++ = exp >> 8;
*p++ = 0xFF & exp;
*p++ = (int8_t)(0xFF & (mant1 >> 24));
*p++ = (int8_t)(0xFF & (mant1 >> 16));
*p++ = (int8_t)(0xFF & (mant1 >> 8));
*p++ = (int8_t)(0xFF & mant1);
*p++ = (int8_t)(0xFF & (mant0 >> 24));
*p++ = (int8_t)(0xFF & (mant0 >> 16));
*p++ = (int8_t)(0xFF & (mant0 >> 8));
*p++ = (int8_t)(0xFF & mant0);
}

//=============================================================
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82 changes: 82 additions & 0 deletions tests/AiffSampleRateTests.cpp
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Original file line number Diff line number Diff line change
@@ -0,0 +1,82 @@
#include <doctest.h>
#include <AudioFile.h>

struct AiffSampleRateTestsTag {};

template<>
class AudioFileUnitTests<AiffSampleRateTestsTag>
{
public:
template<class T>
static inline AudioFile<T>* get(AudioFile<T>& aufile)
{
return &aufile;
}

template<class T>
static inline uint32_t getSampleRate (AudioFile<T>& aufile, const std::vector<uint8_t>& fileData)
{
return aufile.getAiffSampleRate(fileData, 0);
}

template<class T>
static inline void setSampleRate (AudioFile<T>& aufile, std::vector<uint8_t>& fileData, uint32_t sampleRate)
{
aufile.addSampleRateToAiffData(fileData, sampleRate);
}
};

using AiffSampleRateTests = AudioFileUnitTests<AiffSampleRateTestsTag>;

//=============================================================
TEST_SUITE ("Aiff Sample Rate Tests")
{
//=============================================================
TEST_CASE ("GeneralTests::CopyConstructor")
{
struct SampleRateInfo
{
uint32_t sampleRate;
std::vector<uint8_t> data;
};

std::vector<SampleRateInfo> sampleRates =
{
{ 8000, { 64, 11, 250, 0, 0, 0, 0, 0, 0, 0 } },
{ 11025, { 64, 12, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 16000, { 64, 12, 250, 0, 0, 0, 0, 0, 0, 0 } },
{ 22050, { 64, 13, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 32000, { 64, 13, 250, 0, 0, 0, 0, 0, 0, 0 } },
{ 37800, { 64, 14, 147, 168, 0, 0, 0, 0, 0, 0 } },
{ 44056, { 64, 14, 172, 24, 0, 0, 0, 0, 0, 0 } },
{ 44100, { 64, 14, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 47250, { 64, 14, 184, 146, 0, 0, 0, 0, 0, 0 } },
{ 48000, { 64, 14, 187, 128, 0, 0, 0, 0, 0, 0 } },
{ 50000, { 64, 14, 195, 80, 0, 0, 0, 0, 0, 0 } },
{ 50400, { 64, 14, 196, 224, 0, 0, 0, 0, 0, 0 } },
{ 88200, { 64, 15, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 96000, { 64, 15, 187, 128, 0, 0, 0, 0, 0, 0 } },
{ 176400, { 64, 16, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 192000, { 64, 16, 187, 128, 0, 0, 0, 0, 0, 0 } },
{ 352800, { 64, 17, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 2822400, { 64, 20, 172, 68, 0, 0, 0, 0, 0, 0 } },
{ 5644800, { 64, 21, 172, 68, 0, 0, 0, 0, 0, 0 } }
};

AudioFile<float> aufile;

// Convert IEEE 80 bits to uint32_t.
for(const SampleRateInfo& info : sampleRates)
{
REQUIRE_EQ(AiffSampleRateTests::getSampleRate(aufile, info.data), info.sampleRate);
}

// Convert uint32_t to IEEE 80 bits.
for(const SampleRateInfo& info : sampleRates)
{
std::vector<uint8_t> data;
AiffSampleRateTests::setSampleRate(aufile, data, info.sampleRate);
REQUIRE_EQ(data, info.data);
}
}
}
2 changes: 1 addition & 1 deletion tests/CMakeLists.txt
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Original file line number Diff line number Diff line change
Expand Up @@ -6,7 +6,7 @@ add_definitions(-DPROJECT_BINARY_DIR="${CMAKE_CURRENT_BINARY_DIR}")
file (COPY test-audio DESTINATION ${CMAKE_CURRENT_BINARY_DIR})
file (MAKE_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR}/audio-write-tests)

add_executable (Tests main.cpp GeneralTests.cpp WavLoadingTests.cpp AiffLoadingTests.cpp FileWritingTests.cpp SampleConversionTests.cpp)
add_executable (Tests main.cpp GeneralTests.cpp WavLoadingTests.cpp AiffLoadingTests.cpp FileWritingTests.cpp SampleConversionTests.cpp AiffSampleRateTests.cpp)
target_compile_features (Tests PRIVATE cxx_std_17)
add_test (NAME Tests COMMAND Tests)

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