Use hardcoded instead of runtime-calculated ff_cos_* tables if

--enable-hardcoded-tables was used.
Due to the size, the code for the tables is generated at compile time.

Originally committed as revision 20232 to svn://svn.ffmpeg.org/ffmpeg/trunk
release/0.6
Reimar Döffinger 15 years ago
parent 6d924b5a5f
commit 16aec74761
  1. 11
      libavcodec/Makefile
  2. 50
      libavcodec/costablegen.c
  3. 4
      libavcodec/dsputil.h
  4. 39
      libavcodec/fft.c

@ -27,7 +27,8 @@ OBJS = allcodecs.o \
# parts needed for many different codecs
OBJS-$(CONFIG_AANDCT) += aandcttab.o
OBJS-$(CONFIG_ENCODERS) += faandct.o jfdctfst.o jfdctint.o
OBJS-$(CONFIG_FFT) += fft.o
FFT-OBJS-$(CONFIG_HARDCODED_TABLES) += cos_tables.o
OBJS-$(CONFIG_FFT) += fft.o $(FFT-OBJS-yes)
OBJS-$(CONFIG_GOLOMB) += golomb.o
OBJS-$(CONFIG_MDCT) += mdct.o
OBJS-$(CONFIG_RDFT) += rdft.o
@ -571,6 +572,14 @@ TESTPROGS-$(HAVE_MMX) += motion
DIRS = alpha arm bfin mlib ppc ps2 sh4 sparc x86
CLEANFILES = cos_tables.c costablegen$(HOSTEXESUF)
include $(SUBDIR)../subdir.mak
$(SUBDIR)dct-test$(EXESUF): $(SUBDIR)dctref.o
$(SUBDIR)costablegen$(HOSTEXESUF): $(SUBDIR)costablegen.c
$(HOSTCC) $(HOSTCFLAGS) $(HOSTLDFLAGS) -o $@ $< $(HOSTLIBS)
$(SUBDIR)cos_tables.c: $(SUBDIR)costablegen$(HOSTEXESUF)
./$< > $@

@ -0,0 +1,50 @@
/*
* Generate a header file for hardcoded ff_cos_* tables
*
* Copyright (c) 2009 Reimar Döffinger <Reimar.Doeffinger@gmx.de>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdio.h>
#include <math.h>
#ifndef M_PI
#define M_PI 3.14159265358979323846
#endif
#define BITS 16
#define FLOATFMT "%.18e"
int main(void)
{
int i, j;
printf("/* This file was generated by libavcodec/costablegen */\n");
printf("#include \"dsputil.h\"\n");
for (i = 4; i <= BITS; i++) {
int m = 1 << i;
double freq = 2*M_PI/m;
printf("const DECLARE_ALIGNED_16(FFTSample, ff_cos_%i[]) = {\n ", m);
for (j = 0; j < m/2 - 1; j++) {
int idx = j > m/4 ? m/2 - j : j;
printf(" "FLOATFMT",", cos(idx*freq));
if ((j & 3) == 3)
printf("\n ");
}
printf(" "FLOATFMT"\n};\n", cos(freq));
}
return 0;
}

@ -742,7 +742,11 @@ typedef struct FFTContext {
#define FF_MDCT_PERM_INTERLEAVE 1
} FFTContext;
#if CONFIG_HARDCODED_TABLES
extern const FFTSample* const ff_cos_tabs[13];
#else
extern FFTSample* const ff_cos_tabs[13];
#endif
/**
* Sets up a complex FFT.

@ -28,20 +28,31 @@
#include "dsputil.h"
#if CONFIG_HARDCODED_TABLES
#define COSTABLE(size) \
extern const DECLARE_ALIGNED_16(FFTSample, ff_cos_##size[size/2]);
#else
#define COSTABLE(size) \
DECLARE_ALIGNED_16(FFTSample, ff_cos_##size[size/2]);
#endif
/* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */
DECLARE_ALIGNED_16(FFTSample, ff_cos_16[8]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_32[16]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_64[32]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_128[64]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_256[128]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_512[256]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_1024[512]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_2048[1024]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_4096[2048]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_8192[4096]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_16384[8192]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_32768[16384]);
DECLARE_ALIGNED_16(FFTSample, ff_cos_65536[32768]);
COSTABLE(16)
COSTABLE(32)
COSTABLE(64)
COSTABLE(128)
COSTABLE(256)
COSTABLE(512)
COSTABLE(1024)
COSTABLE(2048)
COSTABLE(4096)
COSTABLE(8192)
COSTABLE(16384)
COSTABLE(32768)
COSTABLE(65536)
#if CONFIG_HARDCODED_TABLES
const
#endif
FFTSample * const ff_cos_tabs[] = {
ff_cos_16, ff_cos_32, ff_cos_64, ff_cos_128, ff_cos_256, ff_cos_512, ff_cos_1024,
ff_cos_2048, ff_cos_4096, ff_cos_8192, ff_cos_16384, ff_cos_32768, ff_cos_65536,
@ -93,6 +104,7 @@ av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
if (HAVE_MMX) ff_fft_init_mmx(s);
if (s->split_radix) {
#if !CONFIG_HARDCODED_TABLES
for(j=4; j<=nbits; j++) {
int m = 1<<j;
double freq = 2*M_PI/m;
@ -102,6 +114,7 @@ av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse)
for(i=1; i<m/4; i++)
tab[m/2-i] = tab[i];
}
#endif
for(i=0; i<n; i++)
s->revtab[-split_radix_permutation(i, n, s->inverse) & (n-1)] = i;
s->tmp_buf = av_malloc(n * sizeof(FFTComplex));

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