public void readFile(List <ComplexNumber> mInputNum, long mStartPos = 0)
{
long offset = 0;
FileStream fs = new FileStream(fFileName, FileMode.Open);
if (mStartPos != 0)
{
if (fDataWidth == 8 && fDataNum == 1)
{
fFilePos = mStartPos;
}
if (fDataWidth == 12 && fDataNum == 1)
{
fFilePos = mStartPos * 3 / 2;
}
if (fDataWidth == 12 && fDataNum == 2)
{
fFilePos = mStartPos * 3;
}
if (fDataWidth == 16 && fDataNum == 2)
{
fFilePos = mStartPos * 4;
}
if (fDataWidth == 16 && fDataNum == 1)
{
fFilePos = mStartPos * 2;
}
}
offset = fs.Seek(fFilePos, SeekOrigin.Begin);
if (offset > fs.Length - 5)
{
return;
}
BinaryReader br = new BinaryReader(fs);
ComplexNumber c = new ComplexNumber(0, 0);
if (fDataWidth == 8 && fDataNum == 1)
{
for (long i = 0; i < fMaxNumCount; i++)
{
c.real = (double)(br.ReadByte() - 128);
c.imag = 0;
mInputNum.Add(c);
fFilePos += 1;
}
}
//位宽12，没有虚部
if (fDataWidth == 12 && fDataNum == 1)
{
for (long i = 0; i < fMaxNumCount / 2; i++)
{
byte[] rd = br.ReadBytes(3);
int real = (int)rd[1] & 0x0f;
c.real = ((real << 8) | (rd[0])) - 2048;
c.imag = 0;
mInputNum.Add(c);
real = (int)rd[1] & 0xf0;
c.real = ((real >> 4) | (((int)rd[2]) << 4)) - 2048;
c.imag = 0;
mInputNum.Add(c);
fFilePos += 3;
}
////判断是否有符号
//int mLow = 0;
//int mMid = 0;
//int mHigh = 0;
//for (int i = 0; i < mInputNum.Count; i++)
//{
// if (mInputNum[i].real < 1365)
// mLow++;
// if (mInputNum[i].real > 1365 && mInputNum[i].real < 2730)
// mMid++;
// if (mInputNum[i].real > 2730)
// mHigh++;
//}
////if (mMid <= mLow || mMid <= mHigh)
//{
// for (int i = 0; i < mInputNum.Count; i++)
// {
// double tmpR = mInputNum[i].real;
// double tmpI = mInputNum[i].imag;
// //if (mInputNum[i].real > 2048)
// tmpR = mInputNum[i].real-2048;
// //if (mInputNum[i].imag > 2047)
// // tmpI = 2048 - mInputNum[i].imag;
// mInputNum[i] = new ComplexNumber(tmpR, tmpI);
// }
//}
}
//位宽12，有虚部，无符号
if (fDataWidth == 12 && fDataNum == 2)
{
for (long i = 0; i < fMaxNumCount; i++)
{
byte[] rd = br.ReadBytes(3);
int real = (int)rd[1] & 0x0f;
c.real = ((real << 8) | (rd[0])) - 2048;
real = (int)rd[1] & 0xf0;
c.imag = ((real >> 4) | (((int)rd[2]) << 4)) - 2048;
mInputNum.Add(c);
fFilePos += 3;
}
////判断是否有符号
//int mLow = 0;
//int mMid = 0;
//int mHigh = 0;
//for (int i = 0; i < mInputNum.Count; i++)
//{
// if (mInputNum[i].real < 1365)
// mLow++;
// if (mInputNum[i].real > 1365 && mInputNum[i].real < 2730)
// mMid++;
// if (mInputNum[i].real > 2730)
// mHigh++;
//}
//if (mMid <= mLow || mMid <= mHigh)
//{
// for (int i = 0; i < mInputNum.Count; i++)
// {
// double tmpR = mInputNum[i].real;
// double tmpI = mInputNum[i].imag;
// //if (mInputNum[i].real > 2047)
// tmpR = 2048 - mInputNum[i].real;
// //if (mInputNum[i].imag > 2047)
// tmpI = 2048 - mInputNum[i].imag;
// mInputNum[i] = new ComplexNumber(tmpR, tmpI);
// }
//}
}
//位宽16，有虚部，有符号
if (fDataWidth == 16 && fDataNum == 2)
{
for (long i = 0; i < fMaxNumCount; i++)
{
c.real = br.ReadInt16();
c.imag = br.ReadInt16();
fFilePos += 4;
// long pos = fs.Seek(offset, SeekOrigin.Current);
mInputNum.Add(c);
}
}
//位宽16，没有虚部，有符号
if (fDataWidth == 16 && fDataNum == 1)
{
for (long i = 0; i < fMaxNumCount; i++)
{
int tmp = br.ReadInt16();
//if (tmp >= 2047)
tmp = tmp - 2048;
c.real = tmp;
c.imag = 0;
fFilePos += 2;
// long pos = fs.Seek(offset, SeekOrigin.Current);
mInputNum.Add(c);
}
}
/*
*
* nNumChars = (fDataWidth * fDataNum) / 8;
*
* offset = fs.Length / fMaxNumCount;
* if (offset % 4 != 0)
* offset = offset + (offset % 4);
*
*
* for (long i = 0; i < fMaxNumCount; i++)
* {
* c.real = br.ReadInt16();
* c.imag = br.ReadInt16();
* fFilePos += 4;
* // long pos = fs.Seek(offset, SeekOrigin.Current);
* mInputNum.Add(c);
* // if (pos >= fs.Length)
* // break;
*
*
* }
* */
br.Close();
fs.Close();
}
/// <summary>
/// FFT变换
/// </summary>
///
private void FFT()
{
int fftLen;
int len;
int nLen = fInputEnd - fInputStart;
if (fFFTCount == 0)
{
for (len = 0; len < 20; len++)
{
if (System.Math.Pow((double)2, (double)len) > nLen)
{
break;
}
}
fftLen = (int)System.Math.Pow((double)2, (double)(len - 1));
}
else
{
fftLen = fFFTCount;
}
fFFTNum.Clear();
for (int i = 0; i < fftLen; i++)
{
if (i >= nLen)
{
fFFTNum.Add(new ComplexNumber(0, 0));
}
else
{
fFFTNum.Add(fInputNum[i + fInputStart]);
}
}
BitReOrder();
int n = fFFTNum.Count;
double angle = -2 * Math.PI / n;
ComplexNumber comp = new ComplexNumber(Math.Cos(angle), Math.Sin(angle));
ComplexNumber[] Wcomplex = new ComplexNumber[n / 2];
Wcomplex[0].real = 1;
Wcomplex[0].imag = 0;
for (int i = 1; i < n / 2; i++)//建立权向量索引表
{
Wcomplex[i] = Wcomplex[i - 1] * comp;
}
int wei = (int)Math.Log(n, 2);//求位数
//ComplexNumber[] newW = new ComplexNumber[n / 2];
List <ComplexNumber> newW = new List <ComplexNumber>(n / 2);
for (int i = 0; i < n / 2; i++)
{
newW.Add(new ComplexNumber(0, 0));
}
ComplexNumber temp;
int t;
for (int i = 0; i < wei; i++)
{
for (int l = 0; l < n / 2;) //每级权数组
{
for (int k = 0; k < Math.Pow(2, i); k++)
{
// newW.Add( Wcomplex[(int)(k * Math.Pow(2, (wei - i - 1)))] );
newW[l] = Wcomplex[(int)(k * Math.Pow(2, (wei - i - 1)))];
l++;
}
}
int j = 0, a = 0;
for (int m = 0; m < Math.Pow(2, (wei - i - 1)); m++) //每级分块
{
for (int o = 0; o < (n / 2) / Math.Pow(2, (wei - i - 1)); o++) //每块蝶形运算次数
{
t = (int)(j + Math.Pow(2, i));
temp = fFFTNum[j] + fFFTNum[t] * newW[a];
fFFTNum[t] = fFFTNum[j] - fFFTNum[t] * newW[a];
fFFTNum[j] = temp;
a++; j++;
}
j = j - (int)((n / 2) / Math.Pow(2, (wei - i - 1))) + (int)Math.Pow(2, (i + 1));
}
update((int)((float)i / wei * 100), "正在进行快速傅立叶变换(FFT)");
}
for (int i = 0; i < n; i++)
{
fFFTNum[i] = fFFTNum[i];
}
update(100, "快速傅立叶变换(FFT)完成");
}