-/**
- * Perform the 256-point IMDCT
- */
-static void do_imdct_256(AC3DecodeContext *s, int chindex)
-{
- int i, k;
- DECLARE_ALIGNED_16(float, x[128]);
- FFTComplex z[2][64];
- float *o_ptr = s->tmp_output;
-
- for(i=0; i<2; i++) {
- /* de-interleave coefficients */
- for(k=0; k<128; k++) {
- x[k] = s->transform_coeffs[chindex][2*k+i];
- }
-
- /* run standard IMDCT */
- s->imdct_256.fft.imdct_calc(&s->imdct_256, o_ptr, x, s->tmp_imdct);
-
- /* reverse the post-rotation & reordering from standard IMDCT */
- for(k=0; k<32; k++) {
- z[i][32+k].re = -o_ptr[128+2*k];
- z[i][32+k].im = -o_ptr[2*k];
- z[i][31-k].re = o_ptr[2*k+1];
- z[i][31-k].im = o_ptr[128+2*k+1];
- }
- }
-
- /* apply AC-3 post-rotation & reordering */
- for(k=0; k<64; k++) {
- o_ptr[ 2*k ] = -z[0][ k].im;
- o_ptr[ 2*k+1] = z[0][63-k].re;
- o_ptr[128+2*k ] = -z[0][ k].re;
- o_ptr[128+2*k+1] = z[0][63-k].im;
- o_ptr[256+2*k ] = -z[1][ k].re;
- o_ptr[256+2*k+1] = z[1][63-k].im;
- o_ptr[384+2*k ] = z[1][ k].im;
- o_ptr[384+2*k+1] = -z[1][63-k].re;
- }
-}
-