Искажение с хором

Я новичок в подключении разработки и C ++. Я пытался написать плагин для хора, используя XCode Audio Unit Template. Однако, когда я проверяю плагин синусоидальной волной, я слышу легкое искажение. Я полагаю, что я что-то не так сделал с техникой интерполяции, которую я использую, хотя я проходил это тысячу раз и не мог понять, что я сделал неправильно Вот код, который я написал, который включает в себя важные части аудиоустройства:

    private: //state variables...
enum {kWaveArraySize = 2000}; //number of points in the LFO sine array to hold the points
float mSine[kWaveArraySize];
float *waveArrayPointer;      //pointer to point in the array Variable to hold Sampling Rate
Float32 SR;
long mSamplesProcessed;          //variable to keep track of samples processed

enum {sampleLimit = (int)10E6};  //limit to reset sine wave
float mCurrentScale, mNextScale; //scaling factor for the LFO sine
TAUBuffer<Float32> Buffer;       //circular buffer
Float32 rawIndex;                //raw read Index
UInt32 ReadIndex, NextIndex;     //the Read Index and the sample  after the Read Index for Linear InterpolationUInt32 WriteIndex;               //the Write Index
UInt32 BufferSize;               //Size of Buffer
UInt32 MaxBufferSize;            //Allocated Number of Samples
Float32 DelayTime;               //Delay Time going to be calculated according to LFO

Float32 inputSample, outputSample,
freq, Depth,               //Variables to hold the frequency of the LFO and Depth parameter

samplesPerCycle,           //number of samples per LFO cycle
InterpOutput,              //interpolated output variable
fracDelay, DryValue, WetValue;  //fractional Delay, Dry and Wet value variables
VibratoUnit::VibratoUnitKernel::VibratoUnitKernel (AUEffectBase *inAudioUnit) : AUKernelBase (inAudioUnit),
mSamplesProcessed(0), mCurrentScale(0)
{
for (int i = 0; i<kWaveArraySize; ++i)       //loop to calculate one cycle of LFO

{
double radians = i * 2.0 * pi / kWaveArraySize;
mSine[i] = (sin(radians) + 1.0) * 0.5;
}
SR = GetSampleRate();
BufferSize = SR;
MaxBufferSize = BufferSize + 20;
Buffer.AllocateClear(MaxBufferSize);
ReadIndex = MaxBufferSize - 1;
WriteIndex = MaxBufferSize - 1;   //Give both ReadIndex and WriteIndex a Value outside the buffer so they would be reset to 0 in the process methodvoid      VibratoUnit::VibratoUnitKernel::Reset() //Reset and clear
{
mCurrentScale = 0;
mSamplesProcessed = 0;
Buffer.Clear();
}
//------------------PROCESS METHOD-----------------------//

void      VibratoUnit::VibratoUnitKernel::Process(   const Float32    *inSourceP,
Float32          *inDestP,
UInt32          inFramesToProcess,
UInt32         inNumChannels,
bool         &ioSilence )
{UInt32 nSampleFrames = inFramesToProcess;
const Float32 *sourceP = inSourceP;
Float32 *destP = inDestP;
freq = GetParameter(kParamFreq);
Depth = GetParameter(kParamDepth);
Depth = (SR/1000.0)*Depth;
WetValue = GetParameter(kParamDryWet);
DryValue = 1.0 - WetValue;
waveArrayPointer = &mSine[0];
samplesPerCycle = SR/freq;
mNextScale = kWaveArraySize/samplesPerCycle;

//----processing loop----//
while (nSampleFrames-- > 0) {
int index = static_cast<long> (mSamplesProcessed * mCurrentScale)%kWaveArraySize; //Find index for in the LFO wave table

if ((mNextScale != mCurrentScale) && (index == 0))
{
mCurrentScale = mNextScale;
mSamplesProcessed = 0;      //change LFO in 0 crossing
}
if ((mSamplesProcessed >= sampleLimit) && (index == 0))
{
mSamplesProcessed = 0;  // reset samples processed
}
if (WriteIndex >= BufferSize)   //reset write Index if goes outside the buffer

{
WriteIndex = 0;
}
inputSample = *sourceP;

sourceP += inNumChannels;

DelayTime = waveArrayPointer[index]; //receive raw sine value between 0 and 1

DelayTime = (Depth*DelayTime)+Depth; //calculate delay value according to sine wave

rawIndex = WriteIndex - DelayTime;   //calculate rawIndex relative to the write Index positionif (rawIndex < 0) {
rawIndex = BufferSize + rawIndex;
}

ReadIndex = (UInt32)rawIndex;        //calculate readIndex according to rawIndex positionfracDelay = DelayTime - (UInt32)DelayTime; //calculate fractional delay time

NextIndex = ReadIndex + 1;                 //for interpolation

if (NextIndex >= BufferSize)               //bounds checking
{
NextIndex = 0;
}

InterpOutput = (fracDelay*Buffer[ReadIndex]) + ((1.0-fracDelay)*Buffer[NextIndex]);                    //calculate interpolated value

Buffer[ReadIndex] = InterpOutput;  //write the interpolated output to bufferBuffer[WriteIndex] = inputSample;  //write inputsample to buffer
outputSample = (Buffer[ReadIndex]*WetValue) + (inputSample * DryValue);                                //read output sample from buffer
WriteIndex++;             //increment writeIndexmSamplesProcessed++;      //increment samplesprocessed
*destP = outputSample;
destP += inNumChannels;
}
}

Спасибо за вашу помощь заранее.

1

Решение

Задача ещё не решена.

Другие решения

Других решений пока нет …

По вопросам рекламы ammmcru@yandex.ru
Adblock
detector