* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
-#include "dsputil.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include "libavutil/common.h"
+#include "libavutil/mathematics.h"
+#include "fft.h"
/**
- * @file libavcodec/mdct.c
+ * @file
* MDCT/IMDCT transforms.
*/
{
int i, j;
double sum = 0.0, bessel, tmp;
- double local_window[n];
+ double local_window[FF_KBD_WINDOW_MAX];
double alpha2 = (alpha * M_PI / n) * (alpha * M_PI / n);
+ assert(n <= FF_KBD_WINDOW_MAX);
+
for (i = 0; i < n; i++) {
tmp = i * (n - i) * alpha2;
bessel = 1.0;
window[i] = sqrt(local_window[i] / sum);
}
-DECLARE_ALIGNED(16, float, ff_sine_32 [ 32]);
-DECLARE_ALIGNED(16, float, ff_sine_64 [ 64]);
-DECLARE_ALIGNED(16, float, ff_sine_128 [ 128]);
-DECLARE_ALIGNED(16, float, ff_sine_256 [ 256]);
-DECLARE_ALIGNED(16, float, ff_sine_512 [ 512]);
-DECLARE_ALIGNED(16, float, ff_sine_1024[1024]);
-DECLARE_ALIGNED(16, float, ff_sine_2048[2048]);
-DECLARE_ALIGNED(16, float, ff_sine_4096[4096]);
-float * const ff_sine_windows[] = {
- NULL, NULL, NULL, NULL, NULL, // unused
- ff_sine_32 , ff_sine_64 ,
- ff_sine_128, ff_sine_256, ff_sine_512, ff_sine_1024, ff_sine_2048, ff_sine_4096
-};
-
-// Generate a sine window.
-av_cold void ff_sine_window_init(float *window, int n) {
- int i;
- for(i = 0; i < n; i++)
- window[i] = sinf((i + 0.5) * (M_PI / (2.0 * n)));
-}
+#include "mdct_tablegen.h"
/**
* init MDCT or IMDCT computation.
{
int n, n4, i;
double alpha, theta;
+ int tstep;
memset(s, 0, sizeof(*s));
n = 1 << nbits;
s->mdct_bits = nbits;
s->mdct_size = n;
n4 = n >> 2;
- s->tcos = av_malloc(n4 * sizeof(FFTSample));
+ s->permutation = FF_MDCT_PERM_NONE;
+
+ if (ff_fft_init(s, s->mdct_bits - 2, inverse) < 0)
+ goto fail;
+
+ s->tcos = av_malloc(n/2 * sizeof(FFTSample));
if (!s->tcos)
goto fail;
- s->tsin = av_malloc(n4 * sizeof(FFTSample));
- if (!s->tsin)
+
+ switch (s->permutation) {
+ case FF_MDCT_PERM_NONE:
+ s->tsin = s->tcos + n4;
+ tstep = 1;
+ break;
+ case FF_MDCT_PERM_INTERLEAVE:
+ s->tsin = s->tcos + 1;
+ tstep = 2;
+ break;
+ default:
goto fail;
+ }
theta = 1.0 / 8.0 + (scale < 0 ? n4 : 0);
scale = sqrt(fabs(scale));
for(i=0;i<n4;i++) {
alpha = 2 * M_PI * (i + theta) / n;
- s->tcos[i] = -cos(alpha) * scale;
- s->tsin[i] = -sin(alpha) * scale;
+ s->tcos[i*tstep] = -cos(alpha) * scale;
+ s->tsin[i*tstep] = -sin(alpha) * scale;
}
- if (ff_fft_init(s, s->mdct_bits - 2, inverse) < 0)
- goto fail;
return 0;
fail:
- av_freep(&s->tcos);
- av_freep(&s->tsin);
+ ff_mdct_end(s);
return -1;
}
av_cold void ff_mdct_end(FFTContext *s)
{
av_freep(&s->tcos);
- av_freep(&s->tsin);
ff_fft_end(s);
}