diff options
Diffstat (limited to 'libavcodec/fft_template.c')
| -rw-r--r-- | libavcodec/fft_template.c | 189 |
1 files changed, 182 insertions, 7 deletions
diff --git a/libavcodec/fft_template.c b/libavcodec/fft_template.c index 808f317..23ea453 100644 --- a/libavcodec/fft_template.c +++ b/libavcodec/fft_template.c @@ -4,20 +4,20 @@ * Copyright (c) 2002 Fabrice Bellard * Partly based on libdjbfft by D. J. Bernstein * - * This file is part of Libav. + * This file is part of FFmpeg. * - * Libav is free software; you can redistribute it and/or + * 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. * - * Libav is distributed in the hope that it will be useful, + * 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 Libav; if not, write to the Free Software + * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ @@ -32,6 +32,10 @@ #include "fft.h" #include "fft-internal.h" +#if FFT_FIXED_32 +#include "fft_table.h" +#else /* FFT_FIXED_32 */ + /* cos(2*pi*x/n) for 0<=x<=n/4, followed by its reverse */ #if !CONFIG_HARDCODED_TABLES COSTABLE(16); @@ -65,6 +69,8 @@ COSTABLE_CONST FFTSample * const FFT_NAME(ff_cos_tabs)[] = { FFT_NAME(ff_cos_65536), }; +#endif /* FFT_FIXED_32 */ + static void fft_permute_c(FFTContext *s, FFTComplex *z); static void fft_calc_c(FFTContext *s, FFTComplex *z); @@ -81,7 +87,7 @@ static int split_radix_permutation(int i, int n, int inverse) av_cold void ff_init_ff_cos_tabs(int index) { -#if !CONFIG_HARDCODED_TABLES +#if (!CONFIG_HARDCODED_TABLES) && (!FFT_FIXED_32) int i; int m = 1<<index; double freq = 2*M_PI/m; @@ -157,26 +163,34 @@ av_cold int ff_fft_init(FFTContext *s, int nbits, int inverse) s->mdct_calc = ff_mdct_calc_c; #endif +#if FFT_FIXED_32 + { + int n=0; + ff_fft_lut_init(ff_fft_offsets_lut, 0, 1 << 16, &n); + } +#else /* FFT_FIXED_32 */ #if FFT_FLOAT if (ARCH_AARCH64) ff_fft_init_aarch64(s); if (ARCH_ARM) ff_fft_init_arm(s); if (ARCH_PPC) ff_fft_init_ppc(s); if (ARCH_X86) ff_fft_init_x86(s); if (CONFIG_MDCT) s->mdct_calcw = s->mdct_calc; + if (HAVE_MIPSFPU) ff_fft_init_mips(s); #else if (CONFIG_MDCT) s->mdct_calcw = ff_mdct_calcw_c; if (ARCH_ARM) ff_fft_fixed_init_arm(s); #endif - for(j=4; j<=nbits; j++) { ff_init_ff_cos_tabs(j); } +#endif /* FFT_FIXED_32 */ + if (s->fft_permutation == FF_FFT_PERM_AVX) { fft_perm_avx(s); } else { for(i=0; i<n; i++) { - int j = i; + j = i; if (s->fft_permutation == FF_FFT_PERM_SWAP_LSBS) j = (j&~3) | ((j>>1)&1) | ((j<<1)&2); s->revtab[-split_radix_permutation(i, n, s->inverse) & (n-1)] = j; @@ -206,6 +220,166 @@ av_cold void ff_fft_end(FFTContext *s) av_freep(&s->tmp_buf); } +#if FFT_FIXED_32 + +static void fft_calc_c(FFTContext *s, FFTComplex *z) { + + int nbits, i, n, num_transforms, offset, step; + int n4, n2, n34; + FFTSample tmp1, tmp2, tmp3, tmp4, tmp5, tmp6, tmp7, tmp8; + FFTComplex *tmpz; + const int fft_size = (1 << s->nbits); + int64_t accu; + + num_transforms = (0x2aab >> (16 - s->nbits)) | 1; + + for (n=0; n<num_transforms; n++){ + offset = ff_fft_offsets_lut[n] << 2; + tmpz = z + offset; + + tmp1 = tmpz[0].re + tmpz[1].re; + tmp5 = tmpz[2].re + tmpz[3].re; + tmp2 = tmpz[0].im + tmpz[1].im; + tmp6 = tmpz[2].im + tmpz[3].im; + tmp3 = tmpz[0].re - tmpz[1].re; + tmp8 = tmpz[2].im - tmpz[3].im; + tmp4 = tmpz[0].im - tmpz[1].im; + tmp7 = tmpz[2].re - tmpz[3].re; + + tmpz[0].re = tmp1 + tmp5; + tmpz[2].re = tmp1 - tmp5; + tmpz[0].im = tmp2 + tmp6; + tmpz[2].im = tmp2 - tmp6; + tmpz[1].re = tmp3 + tmp8; + tmpz[3].re = tmp3 - tmp8; + tmpz[1].im = tmp4 - tmp7; + tmpz[3].im = tmp4 + tmp7; + } + + if (fft_size < 8) + return; + + num_transforms = (num_transforms >> 1) | 1; + + for (n=0; n<num_transforms; n++){ + offset = ff_fft_offsets_lut[n] << 3; + tmpz = z + offset; + + tmp1 = tmpz[4].re + tmpz[5].re; + tmp3 = tmpz[6].re + tmpz[7].re; + tmp2 = tmpz[4].im + tmpz[5].im; + tmp4 = tmpz[6].im + tmpz[7].im; + tmp5 = tmp1 + tmp3; + tmp7 = tmp1 - tmp3; + tmp6 = tmp2 + tmp4; + tmp8 = tmp2 - tmp4; + + tmp1 = tmpz[4].re - tmpz[5].re; + tmp2 = tmpz[4].im - tmpz[5].im; + tmp3 = tmpz[6].re - tmpz[7].re; + tmp4 = tmpz[6].im - tmpz[7].im; + + tmpz[4].re = tmpz[0].re - tmp5; + tmpz[0].re = tmpz[0].re + tmp5; + tmpz[4].im = tmpz[0].im - tmp6; + tmpz[0].im = tmpz[0].im + tmp6; + tmpz[6].re = tmpz[2].re - tmp8; + tmpz[2].re = tmpz[2].re + tmp8; + tmpz[6].im = tmpz[2].im + tmp7; + tmpz[2].im = tmpz[2].im - tmp7; + + accu = (int64_t)Q31(M_SQRT1_2)*(tmp1 + tmp2); + tmp5 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)Q31(M_SQRT1_2)*(tmp3 - tmp4); + tmp7 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)Q31(M_SQRT1_2)*(tmp2 - tmp1); + tmp6 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)Q31(M_SQRT1_2)*(tmp3 + tmp4); + tmp8 = (int32_t)((accu + 0x40000000) >> 31); + tmp1 = tmp5 + tmp7; + tmp3 = tmp5 - tmp7; + tmp2 = tmp6 + tmp8; + tmp4 = tmp6 - tmp8; + + tmpz[5].re = tmpz[1].re - tmp1; + tmpz[1].re = tmpz[1].re + tmp1; + tmpz[5].im = tmpz[1].im - tmp2; + tmpz[1].im = tmpz[1].im + tmp2; + tmpz[7].re = tmpz[3].re - tmp4; + tmpz[3].re = tmpz[3].re + tmp4; + tmpz[7].im = tmpz[3].im + tmp3; + tmpz[3].im = tmpz[3].im - tmp3; + } + + step = 1 << ((MAX_LOG2_NFFT-4) - 4); + n4 = 4; + + for (nbits=4; nbits<=s->nbits; nbits++){ + n2 = 2*n4; + n34 = 3*n4; + num_transforms = (num_transforms >> 1) | 1; + + for (n=0; n<num_transforms; n++){ + const FFTSample *w_re_ptr = ff_w_tab_sr + step; + const FFTSample *w_im_ptr = ff_w_tab_sr + MAX_FFT_SIZE/(4*16) - step; + offset = ff_fft_offsets_lut[n] << nbits; + tmpz = z + offset; + + tmp5 = tmpz[ n2].re + tmpz[n34].re; + tmp1 = tmpz[ n2].re - tmpz[n34].re; + tmp6 = tmpz[ n2].im + tmpz[n34].im; + tmp2 = tmpz[ n2].im - tmpz[n34].im; + + tmpz[ n2].re = tmpz[ 0].re - tmp5; + tmpz[ 0].re = tmpz[ 0].re + tmp5; + tmpz[ n2].im = tmpz[ 0].im - tmp6; + tmpz[ 0].im = tmpz[ 0].im + tmp6; + tmpz[n34].re = tmpz[n4].re - tmp2; + tmpz[ n4].re = tmpz[n4].re + tmp2; + tmpz[n34].im = tmpz[n4].im + tmp1; + tmpz[ n4].im = tmpz[n4].im - tmp1; + + for (i=1; i<n4; i++){ + FFTSample w_re = w_re_ptr[0]; + FFTSample w_im = w_im_ptr[0]; + accu = (int64_t)w_re*tmpz[ n2+i].re; + accu += (int64_t)w_im*tmpz[ n2+i].im; + tmp1 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)w_re*tmpz[ n2+i].im; + accu -= (int64_t)w_im*tmpz[ n2+i].re; + tmp2 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)w_re*tmpz[n34+i].re; + accu -= (int64_t)w_im*tmpz[n34+i].im; + tmp3 = (int32_t)((accu + 0x40000000) >> 31); + accu = (int64_t)w_re*tmpz[n34+i].im; + accu += (int64_t)w_im*tmpz[n34+i].re; + tmp4 = (int32_t)((accu + 0x40000000) >> 31); + + tmp5 = tmp1 + tmp3; + tmp1 = tmp1 - tmp3; + tmp6 = tmp2 + tmp4; + tmp2 = tmp2 - tmp4; + + tmpz[ n2+i].re = tmpz[ i].re - tmp5; + tmpz[ i].re = tmpz[ i].re + tmp5; + tmpz[ n2+i].im = tmpz[ i].im - tmp6; + tmpz[ i].im = tmpz[ i].im + tmp6; + tmpz[n34+i].re = tmpz[n4+i].re - tmp2; + tmpz[ n4+i].re = tmpz[n4+i].re + tmp2; + tmpz[n34+i].im = tmpz[n4+i].im + tmp1; + tmpz[ n4+i].im = tmpz[n4+i].im - tmp1; + + w_re_ptr += step; + w_im_ptr -= step; + } + } + step >>= 1; + n4 <<= 1; + } +} + +#else /* FFT_FIXED_32 */ + #define BUTTERFLIES(a0,a1,a2,a3) {\ BF(t3, t5, t5, t1);\ BF(a2.re, a0.re, a0.re, t5);\ @@ -351,3 +525,4 @@ static void fft_calc_c(FFTContext *s, FFTComplex *z) { fft_dispatch[s->nbits-2](z); } +#endif /* FFT_FIXED_32 */ |
