/// <summary>Processes the specified input data.</summary>
/// <param name="inputData">The input data.</param>
/// <param name="inputOffset">The offset of the first value to process.</param>
/// <param name="inputStride">The stride in the input data.</param>
/// <param name="count">The number of values to process.</param>
/// <returns>The number of resampled values.</returns>
public int Process(float[] inputData, int inputOffset, int inputStride, int count)
{
//resize input buffer, *preserve data*
int requiredBufferSize = writeIndex + count;
if (inData.Length < requiredBufferSize)
{
Array.Resize(ref inData, requiredBufferSize);
}
//de-interleave input data and write to the buffer
Dsp.StridedToFloat(inputData, inputOffset, inputStride, inData, writeIndex, count);
writeIndex += count;
int unusedCount = writeIndex - writeIndex0;
//estimate output count
int maxOutCount = (int)(((long)unusedCount * outRate) / inRate) + 2; //+2 is from the example
if (OutData == null || OutData.Length < maxOutCount)
{
OutData = new float[maxOutCount];
}
int outCount = 0;
fixed(float *pSrc = inData, pDst = OutData)
fixed(double *pTime = &readIndex)
{
//resample
IppStatus rc = Ipp.ippsResamplePolyphaseFixed_32f(pSrc, unusedCount, pDst, 1f, pTime, &outCount, pSpec);
IppException.Check(rc);
int usedCount = (int)readIndex - readIndex0;
//shift unused data back in the buffer
rc = sp.ippsMove_32f(pSrc + usedCount, pSrc, writeIndex - usedCount);
IppException.Check(rc);
readIndex -= usedCount;
writeIndex -= usedCount;
}
return(outCount);
}
/// <summary>Writes one of the channels of the strided data to the ring buffer.</summary>
/// <param name="data">The data.</param>
/// <param name="offset">The offset to the first value.</param>
/// <param name="inFloatCount">The number of the input floating point values.</param>
/// <param name="format">The format of the data.</param>
public void WriteStrided(float[] data, int offset, int inFloatCount, SignalFormat format)
{
//single channel, just copy
if (format.Channels == 1)
{
Write(data, offset, inFloatCount);
}
//multiple complex channels
else if (format.IsComplex)
{
int stride = format.Channels * Dsp.COMPONENTS_IN_COMPLEX;
int floatCount = inFloatCount / format.Channels;
int complexCount = inFloatCount / stride;
if (buffer == null || this.buffer.Length < floatCount)
{
buffer = new float[floatCount];
}
Dsp.StridedToComplex(data, offset, stride, buffer, 0, complexCount);
Write(buffer, 0, floatCount);
}
//multiple real channels
else
{
int floatCount = inFloatCount / format.Channels;
if (buffer == null || this.buffer.Length < floatCount)
{
buffer = new float[floatCount];
}
Dsp.StridedToFloat(data, offset, format.Channels, buffer, 0, floatCount);
Write(buffer, 0, floatCount);
}
}