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Diffstat (limited to 'audio/simpleaudiosample/Source/Utilities/ToneGenerator.cpp')
| -rw-r--r-- | audio/simpleaudiosample/Source/Utilities/ToneGenerator.cpp | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/audio/simpleaudiosample/Source/Utilities/ToneGenerator.cpp b/audio/simpleaudiosample/Source/Utilities/ToneGenerator.cpp new file mode 100644 index 00000000..f50e81e1 --- /dev/null +++ b/audio/simpleaudiosample/Source/Utilities/ToneGenerator.cpp @@ -0,0 +1,285 @@ +/*++ + +Copyright (c) Microsoft Corporation All Rights Reserved + +Module Name: + + ToneGenerator + +Abstract: + + Implementation of Simple Audio Sample sine wave generator + +--*/ +#include "definitions.h" +#include "ToneGenerator.h" + +const double TWO_PI = M_PI * 2; + +extern DWORD g_DisableToneGenerator; + +// +// Double to long conversion. +// +long ConvertToLong(double Value) +{ + return (long)(Value * _I32_MAX); +}; + +// +// Double to short conversion. +// +short ConvertToShort(double Value) +{ + return (short)(Value * _I16_MAX); +}; + +// +// Double to char conversion. +// +unsigned char ConvertToUChar(double Value) +{ + const double F_127_5 = 127.5; + return (unsigned char)(Value * F_127_5 + F_127_5); +}; + +// +// Ctor: basic init. +// +ToneGenerator::ToneGenerator() +: m_Frequency(0), + m_ChannelCount(0), + m_BitsPerSample(0), + m_SamplesPerSecond(0), + m_Mute(false), + m_PartialFrame(NULL), + m_PartialFrameBytes(0), + m_FrameSize(0) +{ + // Theta (double) and SampleIncrement (double) are init in the Init() method + // after saving the floating point state. +} + +// +// Dtor: free resources. +// +ToneGenerator::~ToneGenerator() +{ + if (m_PartialFrame) + { + ExFreePoolWithTag(m_PartialFrame, SIMPLEAUDIOSAMPLE_POOLTAG); + m_PartialFrame = NULL; + m_PartialFrameBytes = 0; + } +} + +// +// Init a new frame. +// Note: caller will save and restore the floatingpoint state. +// +#pragma warning(push) +// Caller wraps this routine between KeSaveFloatingPointState/KeRestoreFloatingPointState calls. +#pragma warning(disable: 28110) + +VOID ToneGenerator::InitNewFrame +( + _Out_writes_bytes_(FrameSize) BYTE* Frame, + _In_ DWORD FrameSize +) +{ + double sinValue = m_ToneDCOffset + m_ToneAmplitude * sin( m_Theta ); + + if (FrameSize != (DWORD)m_ChannelCount * m_BitsPerSample/8) + { + ASSERT(FALSE); + RtlZeroMemory(Frame, FrameSize); + return; + } + + for(ULONG i = 0; i < m_ChannelCount; ++i) + { + if (m_BitsPerSample == 8) + { + unsigned char *dataBuffer = reinterpret_cast<unsigned char *>(Frame); + dataBuffer[i] = ConvertToUChar(sinValue); + } + else if (m_BitsPerSample == 16) + { + short *dataBuffer = reinterpret_cast<short *>(Frame); + dataBuffer[i] = ConvertToShort(sinValue); + } + else if (m_BitsPerSample == 24) + { + BYTE *dataBuffer = Frame; + long val = ConvertToLong(sinValue); + val = val >> 8; + RtlCopyMemory(dataBuffer, &val, 3); + } + else if (m_BitsPerSample == 32) + { + long *dataBuffer = reinterpret_cast<long *>(Frame); + dataBuffer[i] = ConvertToLong(sinValue); + } + } + + m_Theta += m_SampleIncrement; + if (m_Theta >= TWO_PI) + { + m_Theta -= TWO_PI; + } +} +#pragma warning(pop) + +// +// GenerateSamples() +// +// Generate a sine wave that fits into the specified buffer. +// +// Buffer - Buffer to hold the samples +// BufferLength - Length of the buffer. +// +// +void ToneGenerator::GenerateSine +( + _Out_writes_bytes_(BufferLength) BYTE *Buffer, + _In_ size_t BufferLength +) +{ + NTSTATUS status; + KFLOATING_SAVE saveData; + BYTE * buffer; + size_t length; + size_t copyBytes; + + // if muted, or tone generator disabled via registry, + // we deliver silence. + if (m_Mute || g_DisableToneGenerator) + { + goto ZeroBuffer; + } + + status = KeSaveFloatingPointState(&saveData); + if (!NT_SUCCESS(status)) + { + goto ZeroBuffer; + } + + buffer = Buffer; + length = BufferLength; + + // + // Check if we have any residual frame bytes from the last time. + // + if (m_PartialFrameBytes) + { + ASSERT(m_FrameSize > m_PartialFrameBytes); + DWORD offset = m_FrameSize - m_PartialFrameBytes; + copyBytes = MIN(m_PartialFrameBytes, length); + RtlCopyMemory(buffer, m_PartialFrame + offset, copyBytes); + RtlZeroMemory(m_PartialFrame + offset, copyBytes); + length -= copyBytes; + buffer += copyBytes; + m_PartialFrameBytes = 0; + } + + IF_TRUE_JUMP(length == 0, Done); + + // + // Copy all the aligned frames. + // + + size_t frames = length/m_FrameSize; + + for (size_t i = 0; i < frames; ++i) + { + InitNewFrame(buffer, m_FrameSize); + buffer += m_FrameSize; + length -= m_FrameSize; + } + + IF_TRUE_JUMP(length == 0, Done); + + // + // Copy any partial frame at the end. + // + ASSERT(m_FrameSize > length); + InitNewFrame(m_PartialFrame, m_FrameSize); + RtlCopyMemory(buffer, m_PartialFrame, length); + RtlZeroMemory(m_PartialFrame, length); + m_PartialFrameBytes = m_FrameSize - (DWORD)length; + +Done: + KeRestoreFloatingPointState(&saveData); + return; + +ZeroBuffer: + RtlZeroMemory(Buffer, BufferLength); + return; +} + +NTSTATUS ToneGenerator::Init +( + _In_ DWORD ToneFrequency, + _In_ double ToneAmplitude, + _In_ double ToneDCOffset, + _In_ double ToneInitialPhase, + _In_ PWAVEFORMATEXTENSIBLE WfExt +) +{ + NTSTATUS status = STATUS_SUCCESS; + KFLOATING_SAVE saveData; + + // + // This sample supports PCM formats only. + // + if ((WfExt->Format.wFormatTag != WAVE_FORMAT_PCM && + !(WfExt->Format.wFormatTag == WAVE_FORMAT_EXTENSIBLE && + IsEqualGUIDAligned(WfExt->SubFormat, KSDATAFORMAT_SUBTYPE_PCM)))) + { + status = STATUS_NOT_SUPPORTED; + } + IF_FAILED_JUMP(status, Done); + + // + // Save floating state (just in case). + // + status = KeSaveFloatingPointState(&saveData); + IF_FAILED_JUMP(status, Done); + + // + // Basic init. + // + m_Theta = ToneInitialPhase; + m_Frequency = ToneFrequency; + m_ToneAmplitude = ToneAmplitude; + m_ToneDCOffset = ToneDCOffset; + + m_ChannelCount = WfExt->Format.nChannels; // # channels. + m_BitsPerSample = WfExt->Format.wBitsPerSample; // bits per sample. + m_SamplesPerSecond = WfExt->Format.nSamplesPerSec; // samples per sec. + m_Mute = false; + m_SampleIncrement = (m_Frequency * TWO_PI) / (double)m_SamplesPerSecond; + m_FrameSize = (DWORD)m_ChannelCount * m_BitsPerSample/8; + ASSERT(m_FrameSize == WfExt->Format.nBlockAlign); + + // + // Restore floating state. + // + KeRestoreFloatingPointState(&saveData); + + // + // Allocate a buffer to hold a partial frame. + // + m_PartialFrame = (BYTE*)ExAllocatePool2( + POOL_FLAG_NON_PAGED, + m_FrameSize, + SIMPLEAUDIOSAMPLE_POOLTAG); + + IF_TRUE_ACTION_JUMP(m_PartialFrame == NULL, status = STATUS_INSUFFICIENT_RESOURCES, Done); + + status = STATUS_SUCCESS; + +Done: + return status; +} + |