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-rw-r--r--src/libfaad/mdct.c251
1 files changed, 131 insertions, 120 deletions
diff --git a/src/libfaad/mdct.c b/src/libfaad/mdct.c
index 886f227ff..62031bfed 100644
--- a/src/libfaad/mdct.c
+++ b/src/libfaad/mdct.c
@@ -16,7 +16,7 @@
** along with this program; if not, write to the Free Software
** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
**
-** $Id: mdct.c,v 1.2 2002/08/09 22:36:36 miguelfreitas Exp $
+** $Id: mdct.c,v 1.3 2002/12/16 19:00:39 miguelfreitas Exp $
**/
/*
@@ -31,146 +31,179 @@
*
*
* As of April 6th 2002 completely rewritten.
- * Thanks to the FFTW library this (I)MDCT can now be used for any data
- * size n, where n is divisible by 8.
+ * This (I)MDCT can now be used for any data size n, where n is divisible by 8.
*
*/
-
#include "common.h"
+#include "structs.h"
#include <stdlib.h>
+#ifdef _WIN32_WCE
+#define assert(x)
+#else
#include <assert.h>
+#endif
-#ifdef USE_FFTW
-/* uses fftw (http://www.fftw.org) for very fast arbitrary-n FFT and IFFT */
-#include <fftw.h>
-#else
#include "cfft.h"
-#endif
+#include "mdct.h"
+/* const_tab[]:
+ 0: sqrt(2 / N)
+ 1: cos(2 * PI / N)
+ 2: sin(2 * PI / N)
+ 3: cos(2 * PI * (1/8) / N)
+ 4: sin(2 * PI * (1/8) / N)
+ */
+#ifdef FIXED_POINT
+real_t const_tab[][5] =
+{
+ { 0x800000, 0xFFFFB10, 0xC90FC, 0xFFFFFF0, 0x1921F }, /* 2048 */
+ { 0x8432A5, 0xFFFFA60, 0xD6773, 0xFFFFFF0, 0x1ACEE }, /* 1920 */
+ { 0xB504F3, 0xFFFEC40, 0x1921F1, 0xFFFFFB0, 0x3243F }, /* 1024 */
+ { 0xBAF4BA, 0xFFFE990, 0x1ACEDD, 0xFFFFFA0, 0x359DD }, /* 960 */
+ { 0x16A09E6, 0xFFEC430, 0x648558, 0xFFFFB10, 0xC90FC }, /* 256 */
+ { 0x175E974, 0xFFE98B0, 0x6B3885, 0xFFFFA60, 0xD6773 } /* 240 */
+#ifdef SSR_DEC
+ ,{ 0, 0, 0, 0, 0 }, /* 512 */
+ { 0, 0, 0, 0, 0 } /* 64 */
+#endif
+};
+#else
+#ifdef _MSC_VER
+#pragma warning(disable:4305)
+#pragma warning(disable:4244)
+#endif
+real_t const_tab[][5] =
+{
+ { 0.0312500000, 0.9999952938, 0.0030679568, 0.9999999265, 0.0003834952 }, /* 2048 */
+ { 0.0322748612, 0.9999946356, 0.0032724866, 0.9999999404, 0.0004090615 }, /* 1920 */
+ { 0.0441941738, 0.9999811649, 0.0061358847, 0.9999997020, 0.0007669903 }, /* 1024 */
+ { 0.0456435465, 0.9999786019, 0.0065449383, 0.9999996424, 0.0008181230 }, /* 960 */
+ { 0.0883883476, 0.9996988177, 0.0245412290, 0.9999952912, 0.0030679568 }, /* 256 */
+ { 0.0912870929, 0.9996573329, 0.0261769500, 0.9999946356, 0.0032724866 } /* 240 */
+#ifdef SSR_DEC
+ ,{ 0.062500000, 0.999924702, 0.012271538, 0.999998823, 0.00153398 }, /* 512 */
+ { 0.176776695, 0.995184727, 0.09801714, 0.999924702, 0.012271538 } /* 64 */
+#endif
+};
+#endif
-#include "mdct.h"
+uint8_t map_N_to_idx(uint16_t N)
+{
+ switch(N)
+ {
+ case 2048: return 0;
+ case 1920: return 1;
+ case 1024: return 2;
+ case 960: return 3;
+ case 256: return 4;
+ case 240: return 5;
+#ifdef SSR_DEC
+ case 512: return 6;
+ case 64: return 7;
+#endif
+ }
+ return 0;
+}
-void faad_mdct_init(mdct_info *mdct, uint16_t N)
+mdct_info *faad_mdct_init(uint16_t N)
{
- uint16_t k;
+ uint16_t k, N_idx;
+ real_t cangle, sangle, c, s, cold;
+ real_t scale;
+
+ mdct_info *mdct = (mdct_info*)malloc(sizeof(mdct_info));
assert(N % 8 == 0);
mdct->N = N;
- mdct->sincos = (faad_sincos*)malloc(N/4*sizeof(faad_sincos));
-#ifdef USE_FFTW
- mdct->Z1 = (fftw_complex*)malloc(N/4*sizeof(fftw_complex));
- mdct->Z2 = (fftw_complex*)malloc(N/4*sizeof(fftw_complex));
-#else
- mdct->Z1 = (real_t*)malloc(N/2*sizeof(real_t));
- mdct->Z2 = (faad_complex*)malloc(N/4*sizeof(faad_complex));
-#endif
+ mdct->sincos = (complex_t*)malloc(N/4*sizeof(complex_t));
+ mdct->Z1 = (complex_t*)malloc(N/4*sizeof(complex_t));
+
+ N_idx = map_N_to_idx(N);
+
+ scale = const_tab[N_idx][0];
+ cangle = const_tab[N_idx][1];
+ sangle = const_tab[N_idx][2];
+ c = const_tab[N_idx][3];
+ s = const_tab[N_idx][4];
for (k = 0; k < N/4; k++)
{
- real_t angle = 2.0 * M_PI * (k + 1.0/8.0)/(real_t)N;
- mdct->sincos[k].sin = -sin(angle);
- mdct->sincos[k].cos = -cos(angle);
+ RE(mdct->sincos[k]) = -1*MUL_C_C(c,scale);
+ IM(mdct->sincos[k]) = -1*MUL_C_C(s,scale);
+
+ cold = c;
+ c = MUL_C_C(c,cangle) - MUL_C_C(s,sangle);
+ s = MUL_C_C(s,cangle) + MUL_C_C(cold,sangle);
}
-#ifdef USE_FFTW
- mdct->plan_backward = fftw_create_plan(N/4, FFTW_BACKWARD, FFTW_ESTIMATE);
-#ifdef LTP_DEC
- mdct->plan_forward = fftw_create_plan(N/4, FFTW_FORWARD, FFTW_ESTIMATE);
-#endif
-#else
- /* own implementation */
+ /* initialise fft */
mdct->cfft = cffti(N/4);
-#endif
+
+ return mdct;
}
void faad_mdct_end(mdct_info *mdct)
{
-#ifdef USE_FFTW
- fftw_destroy_plan(mdct->plan_backward);
-#ifdef LTP_DEC
- fftw_destroy_plan(mdct->plan_forward);
-#endif
-#else
cfftu(mdct->cfft);
-#endif
- if (mdct->Z2) free(mdct->Z2);
if (mdct->Z1) free(mdct->Z1);
if (mdct->sincos) free(mdct->sincos);
+
+ if (mdct) free(mdct);
}
void faad_imdct(mdct_info *mdct, real_t *X_in, real_t *X_out)
{
uint16_t k;
-#ifdef USE_FFTW
- fftw_complex *Z1 = mdct->Z1;
- fftw_complex *Z2 = mdct->Z2;
-#else
- real_t *Z1 = mdct->Z1;
- faad_complex *Z2 = mdct->Z2;
-#endif
- faad_sincos *sincos = mdct->sincos;
- real_t fftdata[1024];
+ complex_t x;
+ complex_t *Z1 = mdct->Z1;
+ complex_t *sincos = mdct->sincos;
uint16_t N = mdct->N;
uint16_t N2 = N >> 1;
uint16_t N4 = N >> 2;
uint16_t N8 = N >> 3;
- real_t fac = 2.0/(real_t)N;
-
/* pre-IFFT complex multiplication */
for (k = 0; k < N4; k++)
{
uint16_t n = k << 1;
- real_t x0 = X_in[ n];
- real_t x1 = X_in[N2 - 1 - n];
-#ifdef USE_FFTW
- Z1[k].re = MUL(fac, MUL(x1, sincos[k].cos) - MUL(x0, sincos[k].sin));
- Z1[k].im = MUL(fac, MUL(x0, sincos[k].cos) + MUL(x1, sincos[k].sin));
-#else
- Z1[2*k] = MUL(fac, MUL(x1, sincos[k].cos) - MUL(x0, sincos[k].sin));
- Z1[2*k+1] = MUL(fac, MUL(x0, sincos[k].cos) + MUL(x1, sincos[k].sin));
-#endif
+ RE(x) = X_in[ n];
+ IM(x) = X_in[N2 - 1 - n];
+ RE(Z1[k]) = MUL_R_C(IM(x), RE(sincos[k])) - MUL_R_C(RE(x), IM(sincos[k]));
+ IM(Z1[k]) = MUL_R_C(RE(x), RE(sincos[k])) + MUL_R_C(IM(x), IM(sincos[k]));
}
/* complex IFFT */
-#ifdef USE_FFTW
- fftw_one(mdct->plan_backward, Z1, Z2);
-#else
cfftb(mdct->cfft, Z1);
-#endif
/* post-IFFT complex multiplication */
for (k = 0; k < N4; k++)
{
-#ifdef USE_FFTW
- real_t zr = Z2[k].re;
- real_t zi = Z2[k].im;
-#else
- real_t zr = Z1[2*k];
- real_t zi = Z1[2*k+1];
-#endif
- Z2[k].re = MUL(zr, sincos[k].cos) - MUL(zi, sincos[k].sin);
- Z2[k].im = MUL(zi, sincos[k].cos) + MUL(zr, sincos[k].sin);
+ uint16_t n = k << 1;
+ RE(x) = RE(Z1[k]);
+ IM(x) = IM(Z1[k]);
+
+ RE(Z1[k]) = MUL_R_C(RE(x), RE(sincos[k])) - MUL_R_C(IM(x), IM(sincos[k]));
+ IM(Z1[k]) = MUL_R_C(IM(x), RE(sincos[k])) + MUL_R_C(RE(x), IM(sincos[k]));
}
/* reordering */
for (k = 0; k < N8; k++)
{
uint16_t n = k << 1;
- X_out[ n] = -Z2[N8 + k].im;
- X_out[ 1 + n] = Z2[N8 - 1 - k].re;
- X_out[N4 + n] = -Z2[ k].re;
- X_out[N4 + 1 + n] = Z2[N4 - 1 - k].im;
- X_out[N2 + n] = -Z2[N8 + k].re;
- X_out[N2 + 1 + n] = Z2[N8 - 1 - k].im;
- X_out[N2 + N4 + n] = Z2[ k].im;
- X_out[N2 + N4 + 1 + n] = -Z2[N4 - 1 - k].re;
+ X_out[ n] = IM(Z1[N8 + k]);
+ X_out[ 1 + n] = -RE(Z1[N8 - 1 - k]);
+ X_out[N4 + n] = RE(Z1[ k]);
+ X_out[N4 + 1 + n] = -IM(Z1[N4 - 1 - k]);
+ X_out[N2 + n] = RE(Z1[N8 + k]);
+ X_out[N2 + 1 + n] = -IM(Z1[N8 - 1 - k]);
+ X_out[N2 + N4 + n] = -IM(Z1[ k]);
+ X_out[N2 + N4 + 1 + n] = RE(Z1[N4 - 1 - k]);
}
}
@@ -179,70 +212,48 @@ void faad_mdct(mdct_info *mdct, real_t *X_in, real_t *X_out)
{
uint16_t k;
-#ifdef USE_FFTW
- fftw_complex *Z1 = mdct->Z1;
- fftw_complex *Z2 = mdct->Z2;
-#else
- real_t *Z1 = mdct->Z1;
-#endif
- faad_sincos *sincos = mdct->sincos;
+ complex_t x;
+ complex_t *Z1 = mdct->Z1;
+ complex_t *sincos = mdct->sincos;
uint16_t N = mdct->N;
uint16_t N2 = N >> 1;
uint16_t N4 = N >> 2;
uint16_t N8 = N >> 3;
+ real_t scale = REAL_CONST(N);
/* pre-FFT complex multiplication */
for (k = 0; k < N8; k++)
{
uint16_t n = k << 1;
- real_t zr = X_in[N - N4 - 1 - n] + X_in[N - N4 + n];
- real_t zi = X_in[ N4 + n] - X_in[ N4 - 1 - n];
+ RE(x) = X_in[N - N4 - 1 - n] + X_in[N - N4 + n];
+ IM(x) = X_in[ N4 + n] - X_in[ N4 - 1 - n];
-#ifdef USE_FFTW
- Z1[k ].re = -MUL(zr, sincos[k ].cos) - MUL(zi, sincos[k ].sin);
- Z1[k ].im = -MUL(zi, sincos[k ].cos) + MUL(zr, sincos[k ].sin);
-#else
- Z1[k*2 ] = -MUL(zr, sincos[k ].cos) - MUL(zi, sincos[k ].sin);
- Z1[k*2+1 ] = -MUL(zi, sincos[k ].cos) + MUL(zr, sincos[k ].sin);
-#endif
+ RE(Z1[k]) = -MUL_R_C(RE(x), RE(sincos[k])) - MUL_R_C(IM(x), IM(sincos[k]));
+ IM(Z1[k]) = -MUL_R_C(IM(x), RE(sincos[k])) + MUL_R_C(RE(x), IM(sincos[k]));
- zr = X_in[ N2 - 1 - n] - X_in[ n];
- zi = X_in[ N2 + n] + X_in[N - 1 - n];
+ RE(x) = X_in[N2 - 1 - n] - X_in[ n];
+ IM(x) = X_in[N2 + n] + X_in[N - 1 - n];
-#ifdef USE_FFTW
- Z1[k + N8].re = -MUL(zr, sincos[k + N8].cos) - MUL(zi, sincos[k + N8].sin);
- Z1[k + N8].im = -MUL(zi, sincos[k + N8].cos) + MUL(zr, sincos[k + N8].sin);
-#else
- Z1[k*2 + N8] = -MUL(zr, sincos[k + N8].cos) - MUL(zi, sincos[k + N8].sin);
- Z1[k*2+1 + N8] = -MUL(zi, sincos[k + N8].cos) + MUL(zr, sincos[k + N8].sin);
-#endif
+ RE(Z1[k + N8]) = -MUL_R_C(RE(x), RE(sincos[k + N8])) - MUL_R_C(IM(x), IM(sincos[k + N8]));
+ IM(Z1[k + N8]) = -MUL_R_C(IM(x), RE(sincos[k + N8])) + MUL_R_C(RE(x), IM(sincos[k + N8]));
}
/* complex FFT */
-#ifdef USE_FFTW
- fftw_one(mdct->plan_forward, Z1, Z2);
-#else
cfftf(mdct->cfft, Z1);
-#endif
/* post-FFT complex multiplication */
for (k = 0; k < N4; k++)
{
uint16_t n = k << 1;
-#ifdef USE_FFTW
- real_t zr = MUL(2.0, MUL(Z2[k].re, sincos[k].cos) + MUL(Z2[k].im, sincos[k].sin));
- real_t zi = MUL(2.0, MUL(Z2[k].im, sincos[k].cos) - MUL(Z2[k].re, sincos[k].sin));
-#else
- real_t zr = MUL(2.0, MUL(Z1[k*2], sincos[k].cos) + MUL(Z1[k*2+1], sincos[k].sin));
- real_t zi = MUL(2.0, MUL(Z1[k*2+1], sincos[k].cos) - MUL(Z1[k*2], sincos[k].sin));
-#endif
+ RE(x) = MUL(MUL_R_C(RE(Z1[k]), RE(sincos[k])) + MUL_R_C(IM(Z1[k]), IM(sincos[k])), scale);
+ IM(x) = MUL(MUL_R_C(IM(Z1[k]), RE(sincos[k])) - MUL_R_C(RE(Z1[k]), IM(sincos[k])), scale);
- X_out[ n] = -zr;
- X_out[N2 - 1 - n] = zi;
- X_out[N2 + n] = -zi;
- X_out[N - 1 - n] = zr;
+ X_out[ n] = RE(x);
+ X_out[N2 - 1 - n] = -IM(x);
+ X_out[N2 + n] = IM(x);
+ X_out[N - 1 - n] = -RE(x);
}
}
#endif
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