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Merge remote-tracking branch 'newdev/master'

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Merged-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer
2011-03-21 03:09:46 +01:00
parent 849f80fecb cf752d027f
commit d4a50a2100
44 changed files with 458 additions and 275 deletions
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31
libavcodec/mdct.c
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@@ -30,33 +30,6 @@
* MDCT/IMDCT transforms.
*/
// Generate a Kaiser-Bessel Derived Window.
#define BESSEL_I0_ITER 50 // default: 50 iterations of Bessel I0 approximation
av_cold void ff_kbd_window_init(float *window, float alpha, int n)
{
int i, j;
double sum = 0.0, bessel, tmp;
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;
for (j = BESSEL_I0_ITER; j > 0; j--)
bessel = bessel * tmp / (j * j) + 1;
sum += bessel;
local_window[i] = sum;
}
sum++;
for (i = 0; i < n; i++)
window[i] = sqrt(local_window[i] / sum);
}
#include "mdct_tablegen.h"
/**
* init MDCT or IMDCT computation.
*/
@@ -146,7 +119,7 @@ void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input)
in1 += 2;
in2 -= 2;
}
ff_fft_calc(s, z);
s->fft_calc(s, z);
/* post rotation + reordering */
for(k = 0; k < n8; k++) {
@@ -213,7 +186,7 @@ void ff_mdct_calc_c(FFTContext *s, FFTSample *out, const FFTSample *input)
CMUL(x[j].re, x[j].im, re, im, -tcos[n8 + i], tsin[n8 + i]);
}
ff_fft_calc(s, x);
s->fft_calc(s, x);
/* post rotation */
for(i=0;i<n8;i++) {