JNIEXPORT jint JNICALL
Java_com_h6ah4i_android_media_opensl_audiofx_OpenSLVisualizer_getFftImplNative(JNIEnv *env, jclass clazz, jlong handle,
jbyteArray fft) noexcept
{
if (!handle) {
return OSLMP_RESULT_INVALID_HANDLE;
}
if (!fft) {
return OSLMP_RESULT_ILLEGAL_ARGUMENT;
}
jbyte_critical_array fft_(env, fft);
if (!fft_) {
return OSLMP_RESULT_ERROR;
}
Holder *holder = Holder::fromJniHandle(handle);
int result = holder->visualizer->getFft(reinterpret_cast<int8_t *>(fft_.data()), fft_.length());
return result;
}
void gauss3dd (float *image, int *pnx, int *pny, int *pnz, float *cmppix, float *fhalf) {
/**************************************************************************/
/* 3D Gaussian filter + differentiation (variant of cgauss3d.c) */
/* */
/* inputs: real*4 image(nx,ny,nz) ! image to be filtered */
/* real*4 cmppix(3) ! x, y, z voxel dimensions in cm */
/* real*4 fhalf ! half amplitude frequency in cycles/cm */
/* */
/* variables modified: image ! input image overwritten */
/* */
/* subroutines called: FFT, REALT in FORTRAN source fftsun.f or fftsol.f */
/* FFT algorithm by Richard C. Singleton */
/* */
/* restrictions: mixed radix FFT accepts any nx, ny, nz but */
/* nx must be divisible by 2 */
/**************************************************************************/
float *a, *b;
double q, factor, f2, fx, fy, fz;
int i, k, n1, n2, n2ny, jndex;
int ix, iy, iz, nx, ny, nz, kx, ky, kz;
int one = 1, negone = -1;
nx = *pnx; ny = *pny; nz = *pnz;
if (nx % 2) {
fprintf (stderr, "gauss3d: nx not a multiple of 2\n");
exit (-1);
}
n1 = nx/2;
n2 = n1 + 1;
n2ny = n2*ny;
if (!(a = (float *) malloc (n2*ny*nz * sizeof (float)))) errm ("gauss3d");
if (!(b = (float *) malloc (n2*ny*nz * sizeof (float)))) errm ("gauss3d");
k = jndex = 0;
for (iz = 0; iz < nz; iz++) {
for (iy = 0; iy < ny; iy++) {
for (i = ix = 0; ix < nx; ix += 2, i++) {
(a + k)[i] = image[jndex++];
(b + k)[i] = image[jndex++];
}
fft_ (a + k, b + k, &one, &n1, &one, &negone);
realt_ (a + k, b + k, &one, &n1, &one, &negone);
k += n2;
}}
fft_ (a, b, &nz, &ny, &n2, &negone);
fft_ (a, b, &one, &nz, &n2ny, &negone);
q = -log(2.)/((*fhalf)*(*fhalf));
i = 0;
for (iz = 0; iz < nz; iz++) {
kz = (iz <= nz/2) ? iz : nz - iz;
fz = kz/(nz*cmppix[2]);
for (iy = 0; iy < ny; iy++) {
ky = (iy <= ny/2) ? iy : ny - iy;
fy = ky/(ny*cmppix[1]);
for (ix = 0; ix < n2; ix++) {
kx = (ix <= nx/2) ? ix : nx - ix;
fx = kx/(nx*cmppix[0]);
f2 = fx*fx + fy*fy + fz*fz;
factor = sqrt(f2)*exp (q*f2);
a[i] *= factor;
b[i] *= factor;
i++;
}}}
fft_ (a, b, &one, &nz, &n2ny, &one);
fft_ (a, b, &nz, &ny, &n2, &one);
k = jndex = 0;
for (iz = 0; iz < nz; iz++) {
for (iy = 0; iy < ny; iy++) {
realt_ (a + k, b + k, &one, &n1, &one, &one);
fft_ (a + k, b + k, &one, &n1, &one, &one);
for (i = ix = 0; ix < nx; ix += 2, i++) {
image[jndex++] = (a + k)[i];
image[jndex++] = (b + k)[i];
}
k += n2;
}}
free (a);
free (b);
}
