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Merge remote-tracking branch 'newdev/master'

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* newdev/master:
  mpegts: propagate avio EOF in read_packet()
  configure: Initial support for --target-os=symbian
  Fixed-point FFT and MDCT
  Include dependencies for test programs
  ac3enc: simplify sym_quant()
  flvdec: read index stored in the 'keyframes' tag.
  mov: Add support for zero-sized stsc runs.

Merged-by: Michael Niedermayer <michaelni@gmx.at>
This commit is contained in:
Michael Niedermayer 2011-04-01 02:55:29 +02:00
commit 7ac167493e
16 changed files with 334 additions and 58 deletions
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32
libavcodec/mdct.c
View file

@ -24,12 +24,19 @@
#include "libavutil/common.h"
#include "libavutil/mathematics.h"
#include "fft.h"
#include "fft-internal.h"
/**
* @file
* MDCT/IMDCT transforms.
*/
#if CONFIG_FFT_FLOAT
# define RSCALE(x) (x)
#else
# define RSCALE(x) ((x) >> 1)
#endif
/**
* init MDCT or IMDCT computation.
*/
@ -70,8 +77,8 @@ av_cold int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale)
scale = sqrt(fabs(scale));
for(i=0;i<n4;i++) {
alpha = 2 * M_PI * (i + theta) / n;
s->tcos[i*tstep] = -cos(alpha) * scale;
s->tsin[i*tstep] = -sin(alpha) * scale;
s->tcos[i*tstep] = FIX15(-cos(alpha) * scale);
s->tsin[i*tstep] = FIX15(-sin(alpha) * scale);
}
return 0;
fail:
@ -79,17 +86,6 @@ av_cold int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale)
return -1;
}
/* complex multiplication: p = a * b */
#define CMUL(pre, pim, are, aim, bre, bim) \
{\
FFTSample _are = (are);\
FFTSample _aim = (aim);\
FFTSample _bre = (bre);\
FFTSample _bim = (bim);\
(pre) = _are * _bre - _aim * _bim;\
(pim) = _are * _bim + _aim * _bre;\
}
/**
* Compute the middle half of the inverse MDCT of size N = 2^nbits,
* thus excluding the parts that can be derived by symmetry
@ -161,7 +157,7 @@ void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input)
void ff_mdct_calc_c(FFTContext *s, FFTSample *out, const FFTSample *input)
{
int i, j, n, n8, n4, n2, n3;
FFTSample re, im;
FFTDouble re, im;
const uint16_t *revtab = s->revtab;
const FFTSample *tcos = s->tcos;
const FFTSample *tsin = s->tsin;
@ -175,13 +171,13 @@ void ff_mdct_calc_c(FFTContext *s, FFTSample *out, const FFTSample *input)
/* pre rotation */
for(i=0;i<n8;i++) {
re = -input[2*i+n3] - input[n3-1-2*i];
im = -input[n4+2*i] + input[n4-1-2*i];
re = RSCALE(-input[2*i+n3] - input[n3-1-2*i]);
im = RSCALE(-input[n4+2*i] + input[n4-1-2*i]);
j = revtab[i];
CMUL(x[j].re, x[j].im, re, im, -tcos[i], tsin[i]);
re = input[2*i] - input[n2-1-2*i];
im = -(input[n2+2*i] + input[n-1-2*i]);
re = RSCALE( input[2*i] - input[n2-1-2*i]);
im = RSCALE(-input[n2+2*i] - input[ n-1-2*i]);
j = revtab[n8 + i];
CMUL(x[j].re, x[j].im, re, im, -tcos[n8 + i], tsin[n8 + i]);
}