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加速器框架我已經設置設置功能加速,我看了之後:設置爲FFT在iPhone
Using the Apple FFT and Accelerate Framework
iPhone FFT with Accelerate framework vDSP
和蘋果文檔。
我這樣做:
void fftSetup()
{
COMPLEX_SPLIT A;
FFTSetup setupReal;
uint32_t log2n;
uint32_t n, nOver2;
int32_t stride;
uint32_t i;
float *originalReal, *obtainedReal;
float scale;
uint32_t L = 1024;
float *mag = new float[L/2];
log2n = 10 ;
n = 1 << log2n;
stride = 1;
nOver2 = n/2;
printf("1D real FFT of length log2 (%d) = %d\n\n", n, log2n);
for (i = 0; i < n; i++)
originalReal[i] = (float) (i + 1);
vDSP_ctoz((COMPLEX *) originalReal,2,&A,1,nOver2);
A.realp = (float *) malloc(nOver2 * sizeof(float));
A.imagp = (float *) malloc(nOver2 * sizeof(float));
setupReal = vDSP_create_fftsetup(log2n, FFT_RADIX2);
vDSP_fft_zrip(setupReal, &A, stride, log2n, FFT_FORWARD);
vDSP_fft_zrip(setupReal, &A, stride, log2n, FFT_INVERSE);
//get magnitude;
for(i = 1; i < L/2; i++){
mag[i] = sqrtf(A.realp[i]*A.realp[i] + A.imagp[i] * A.imagp[i]);
}
scale = (float) 1.0/(2 * n);
vDSP_vsmul(A.realp, 1, &scale, A.realp, 1, nOver2);
vDSP_vsmul(A.imagp, 1, &scale, A.imagp, 1, nOver2);
}
問題:
- 我的應用程序沒有錯誤(BAD ACCESS)這個2線之一總是崩潰:
originalReal [i] =(float)(i + 1); //或
vDSP_ctoz((COMPLEX *)originalReal,2,& A,1,nOver2);
我想我沒有爲log2n設置好的值? (10獲得1024窗口?)
我怎麼得到真正的箱子的大小?我的實際fft?我寫在這裏的是一樣的嗎?
我在哪裏輸入我的數據緩存陣列(正是在我的代碼?而不是originalReal?)
非常感謝。
[在音頻緩衝區中使用加速器對FFT進行快速複製](http://stackoverflow.com/questions/14114682/using-the-accelerator-to-fft-on-audio-buffer) –