| /* |
| * Copyright (c) 2019 Lynne <dev@lynne.ee> |
| * Power of two FFT: |
| * Copyright (c) 2008 Loren Merritt |
| * Copyright (c) 2002 Fabrice Bellard |
| * Partly based on libdjbfft by D. J. Bernstein |
| * |
| * 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 |
| */ |
| |
| /* All costabs for a type are defined here */ |
| 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); |
| COSTABLE(131072); |
| DECLARE_ALIGNED(32, FFTComplex, TX_NAME(ff_cos_53))[4]; |
| |
| static FFTSample * const cos_tabs[18] = { |
| NULL, |
| NULL, |
| NULL, |
| NULL, |
| TX_NAME(ff_cos_16), |
| TX_NAME(ff_cos_32), |
| TX_NAME(ff_cos_64), |
| TX_NAME(ff_cos_128), |
| TX_NAME(ff_cos_256), |
| TX_NAME(ff_cos_512), |
| TX_NAME(ff_cos_1024), |
| TX_NAME(ff_cos_2048), |
| TX_NAME(ff_cos_4096), |
| TX_NAME(ff_cos_8192), |
| TX_NAME(ff_cos_16384), |
| TX_NAME(ff_cos_32768), |
| TX_NAME(ff_cos_65536), |
| TX_NAME(ff_cos_131072), |
| }; |
| |
| static av_always_inline void init_cos_tabs_idx(int index) |
| { |
| int m = 1 << index; |
| double freq = 2*M_PI/m; |
| FFTSample *tab = cos_tabs[index]; |
| for(int i = 0; i <= m/4; i++) |
| tab[i] = RESCALE(cos(i*freq)); |
| for(int i = 1; i < m/4; i++) |
| tab[m/2 - i] = tab[i]; |
| } |
| |
| #define INIT_FF_COS_TABS_FUNC(index, size) \ |
| static av_cold void init_cos_tabs_ ## size (void) \ |
| { \ |
| init_cos_tabs_idx(index); \ |
| } |
| |
| INIT_FF_COS_TABS_FUNC(4, 16) |
| INIT_FF_COS_TABS_FUNC(5, 32) |
| INIT_FF_COS_TABS_FUNC(6, 64) |
| INIT_FF_COS_TABS_FUNC(7, 128) |
| INIT_FF_COS_TABS_FUNC(8, 256) |
| INIT_FF_COS_TABS_FUNC(9, 512) |
| INIT_FF_COS_TABS_FUNC(10, 1024) |
| INIT_FF_COS_TABS_FUNC(11, 2048) |
| INIT_FF_COS_TABS_FUNC(12, 4096) |
| INIT_FF_COS_TABS_FUNC(13, 8192) |
| INIT_FF_COS_TABS_FUNC(14, 16384) |
| INIT_FF_COS_TABS_FUNC(15, 32768) |
| INIT_FF_COS_TABS_FUNC(16, 65536) |
| INIT_FF_COS_TABS_FUNC(17, 131072) |
| |
| static av_cold void ff_init_53_tabs(void) |
| { |
| TX_NAME(ff_cos_53)[0] = (FFTComplex){ RESCALE(cos(2 * M_PI / 12)), RESCALE(cos(2 * M_PI / 12)) }; |
| TX_NAME(ff_cos_53)[1] = (FFTComplex){ RESCALE(cos(2 * M_PI / 6)), RESCALE(cos(2 * M_PI / 6)) }; |
| TX_NAME(ff_cos_53)[2] = (FFTComplex){ RESCALE(cos(2 * M_PI / 5)), RESCALE(sin(2 * M_PI / 5)) }; |
| TX_NAME(ff_cos_53)[3] = (FFTComplex){ RESCALE(cos(2 * M_PI / 10)), RESCALE(sin(2 * M_PI / 10)) }; |
| } |
| |
| static CosTabsInitOnce cos_tabs_init_once[] = { |
| { ff_init_53_tabs, AV_ONCE_INIT }, |
| { NULL }, |
| { NULL }, |
| { NULL }, |
| { init_cos_tabs_16, AV_ONCE_INIT }, |
| { init_cos_tabs_32, AV_ONCE_INIT }, |
| { init_cos_tabs_64, AV_ONCE_INIT }, |
| { init_cos_tabs_128, AV_ONCE_INIT }, |
| { init_cos_tabs_256, AV_ONCE_INIT }, |
| { init_cos_tabs_512, AV_ONCE_INIT }, |
| { init_cos_tabs_1024, AV_ONCE_INIT }, |
| { init_cos_tabs_2048, AV_ONCE_INIT }, |
| { init_cos_tabs_4096, AV_ONCE_INIT }, |
| { init_cos_tabs_8192, AV_ONCE_INIT }, |
| { init_cos_tabs_16384, AV_ONCE_INIT }, |
| { init_cos_tabs_32768, AV_ONCE_INIT }, |
| { init_cos_tabs_65536, AV_ONCE_INIT }, |
| { init_cos_tabs_131072, AV_ONCE_INIT }, |
| }; |
| |
| static av_cold void init_cos_tabs(int index) |
| { |
| ff_thread_once(&cos_tabs_init_once[index].control, |
| cos_tabs_init_once[index].func); |
| } |
| |
| static av_always_inline void fft3(FFTComplex *out, FFTComplex *in, |
| ptrdiff_t stride) |
| { |
| FFTComplex tmp[2]; |
| #ifdef TX_INT32 |
| int64_t mtmp[4]; |
| #endif |
| |
| BF(tmp[0].re, tmp[1].im, in[1].im, in[2].im); |
| BF(tmp[0].im, tmp[1].re, in[1].re, in[2].re); |
| |
| out[0*stride].re = in[0].re + tmp[1].re; |
| out[0*stride].im = in[0].im + tmp[1].im; |
| |
| #ifdef TX_INT32 |
| mtmp[0] = (int64_t)TX_NAME(ff_cos_53)[0].re * tmp[0].re; |
| mtmp[1] = (int64_t)TX_NAME(ff_cos_53)[0].im * tmp[0].im; |
| mtmp[2] = (int64_t)TX_NAME(ff_cos_53)[1].re * tmp[1].re; |
| mtmp[3] = (int64_t)TX_NAME(ff_cos_53)[1].re * tmp[1].im; |
| out[1*stride].re = in[0].re - (mtmp[2] + mtmp[0] + 0x40000000 >> 31); |
| out[1*stride].im = in[0].im - (mtmp[3] - mtmp[1] + 0x40000000 >> 31); |
| out[2*stride].re = in[0].re - (mtmp[2] - mtmp[0] + 0x40000000 >> 31); |
| out[2*stride].im = in[0].im - (mtmp[3] + mtmp[1] + 0x40000000 >> 31); |
| #else |
| tmp[0].re = TX_NAME(ff_cos_53)[0].re * tmp[0].re; |
| tmp[0].im = TX_NAME(ff_cos_53)[0].im * tmp[0].im; |
| tmp[1].re = TX_NAME(ff_cos_53)[1].re * tmp[1].re; |
| tmp[1].im = TX_NAME(ff_cos_53)[1].re * tmp[1].im; |
| out[1*stride].re = in[0].re - tmp[1].re + tmp[0].re; |
| out[1*stride].im = in[0].im - tmp[1].im - tmp[0].im; |
| out[2*stride].re = in[0].re - tmp[1].re - tmp[0].re; |
| out[2*stride].im = in[0].im - tmp[1].im + tmp[0].im; |
| #endif |
| } |
| |
| #define DECL_FFT5(NAME, D0, D1, D2, D3, D4) \ |
| static av_always_inline void NAME(FFTComplex *out, FFTComplex *in, \ |
| ptrdiff_t stride) \ |
| { \ |
| FFTComplex z0[4], t[6]; \ |
| \ |
| BF(t[1].im, t[0].re, in[1].re, in[4].re); \ |
| BF(t[1].re, t[0].im, in[1].im, in[4].im); \ |
| BF(t[3].im, t[2].re, in[2].re, in[3].re); \ |
| BF(t[3].re, t[2].im, in[2].im, in[3].im); \ |
| \ |
| out[D0*stride].re = in[0].re + t[0].re + t[2].re; \ |
| out[D0*stride].im = in[0].im + t[0].im + t[2].im; \ |
| \ |
| SMUL(t[4].re, t[0].re, TX_NAME(ff_cos_53)[2].re, TX_NAME(ff_cos_53)[3].re, t[2].re, t[0].re); \ |
| SMUL(t[4].im, t[0].im, TX_NAME(ff_cos_53)[2].re, TX_NAME(ff_cos_53)[3].re, t[2].im, t[0].im); \ |
| CMUL(t[5].re, t[1].re, TX_NAME(ff_cos_53)[2].im, TX_NAME(ff_cos_53)[3].im, t[3].re, t[1].re); \ |
| CMUL(t[5].im, t[1].im, TX_NAME(ff_cos_53)[2].im, TX_NAME(ff_cos_53)[3].im, t[3].im, t[1].im); \ |
| \ |
| BF(z0[0].re, z0[3].re, t[0].re, t[1].re); \ |
| BF(z0[0].im, z0[3].im, t[0].im, t[1].im); \ |
| BF(z0[2].re, z0[1].re, t[4].re, t[5].re); \ |
| BF(z0[2].im, z0[1].im, t[4].im, t[5].im); \ |
| \ |
| out[D1*stride].re = in[0].re + z0[3].re; \ |
| out[D1*stride].im = in[0].im + z0[0].im; \ |
| out[D2*stride].re = in[0].re + z0[2].re; \ |
| out[D2*stride].im = in[0].im + z0[1].im; \ |
| out[D3*stride].re = in[0].re + z0[1].re; \ |
| out[D3*stride].im = in[0].im + z0[2].im; \ |
| out[D4*stride].re = in[0].re + z0[0].re; \ |
| out[D4*stride].im = in[0].im + z0[3].im; \ |
| } |
| |
| DECL_FFT5(fft5, 0, 1, 2, 3, 4) |
| DECL_FFT5(fft5_m1, 0, 6, 12, 3, 9) |
| DECL_FFT5(fft5_m2, 10, 1, 7, 13, 4) |
| DECL_FFT5(fft5_m3, 5, 11, 2, 8, 14) |
| |
| static av_always_inline void fft15(FFTComplex *out, FFTComplex *in, |
| ptrdiff_t stride) |
| { |
| FFTComplex tmp[15]; |
| |
| for (int i = 0; i < 5; i++) |
| fft3(tmp + i, in + i*3, 5); |
| |
| fft5_m1(out, tmp + 0, stride); |
| fft5_m2(out, tmp + 5, stride); |
| fft5_m3(out, tmp + 10, stride); |
| } |
| |
| #define BUTTERFLIES(a0,a1,a2,a3) {\ |
| BF(t3, t5, t5, t1);\ |
| BF(a2.re, a0.re, a0.re, t5);\ |
| BF(a3.im, a1.im, a1.im, t3);\ |
| BF(t4, t6, t2, t6);\ |
| BF(a3.re, a1.re, a1.re, t4);\ |
| BF(a2.im, a0.im, a0.im, t6);\ |
| } |
| |
| // force loading all the inputs before storing any. |
| // this is slightly slower for small data, but avoids store->load aliasing |
| // for addresses separated by large powers of 2. |
| #define BUTTERFLIES_BIG(a0,a1,a2,a3) {\ |
| FFTSample r0=a0.re, i0=a0.im, r1=a1.re, i1=a1.im;\ |
| BF(t3, t5, t5, t1);\ |
| BF(a2.re, a0.re, r0, t5);\ |
| BF(a3.im, a1.im, i1, t3);\ |
| BF(t4, t6, t2, t6);\ |
| BF(a3.re, a1.re, r1, t4);\ |
| BF(a2.im, a0.im, i0, t6);\ |
| } |
| |
| #define TRANSFORM(a0,a1,a2,a3,wre,wim) {\ |
| CMUL(t1, t2, a2.re, a2.im, wre, -wim);\ |
| CMUL(t5, t6, a3.re, a3.im, wre, wim);\ |
| BUTTERFLIES(a0,a1,a2,a3)\ |
| } |
| |
| #define TRANSFORM_ZERO(a0,a1,a2,a3) {\ |
| t1 = a2.re;\ |
| t2 = a2.im;\ |
| t5 = a3.re;\ |
| t6 = a3.im;\ |
| BUTTERFLIES(a0,a1,a2,a3)\ |
| } |
| |
| /* z[0...8n-1], w[1...2n-1] */ |
| #define PASS(name)\ |
| static void name(FFTComplex *z, const FFTSample *wre, unsigned int n)\ |
| {\ |
| FFTSample t1, t2, t3, t4, t5, t6;\ |
| int o1 = 2*n;\ |
| int o2 = 4*n;\ |
| int o3 = 6*n;\ |
| const FFTSample *wim = wre+o1;\ |
| n--;\ |
| \ |
| TRANSFORM_ZERO(z[0],z[o1],z[o2],z[o3]);\ |
| TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\ |
| do {\ |
| z += 2;\ |
| wre += 2;\ |
| wim -= 2;\ |
| TRANSFORM(z[0],z[o1],z[o2],z[o3],wre[0],wim[0]);\ |
| TRANSFORM(z[1],z[o1+1],z[o2+1],z[o3+1],wre[1],wim[-1]);\ |
| } while(--n);\ |
| } |
| |
| PASS(pass) |
| #undef BUTTERFLIES |
| #define BUTTERFLIES BUTTERFLIES_BIG |
| PASS(pass_big) |
| |
| #define DECL_FFT(n,n2,n4)\ |
| static void fft##n(FFTComplex *z)\ |
| {\ |
| fft##n2(z);\ |
| fft##n4(z+n4*2);\ |
| fft##n4(z+n4*3);\ |
| pass(z,TX_NAME(ff_cos_##n),n4/2);\ |
| } |
| |
| static void fft2(FFTComplex *z) |
| { |
| FFTComplex tmp; |
| BF(tmp.re, z[0].re, z[0].re, z[1].re); |
| BF(tmp.im, z[0].im, z[0].im, z[1].im); |
| z[1] = tmp; |
| } |
| |
| static void fft4(FFTComplex *z) |
| { |
| FFTSample t1, t2, t3, t4, t5, t6, t7, t8; |
| |
| BF(t3, t1, z[0].re, z[1].re); |
| BF(t8, t6, z[3].re, z[2].re); |
| BF(z[2].re, z[0].re, t1, t6); |
| BF(t4, t2, z[0].im, z[1].im); |
| BF(t7, t5, z[2].im, z[3].im); |
| BF(z[3].im, z[1].im, t4, t8); |
| BF(z[3].re, z[1].re, t3, t7); |
| BF(z[2].im, z[0].im, t2, t5); |
| } |
| |
| static void fft8(FFTComplex *z) |
| { |
| FFTSample t1, t2, t3, t4, t5, t6; |
| |
| fft4(z); |
| |
| BF(t1, z[5].re, z[4].re, -z[5].re); |
| BF(t2, z[5].im, z[4].im, -z[5].im); |
| BF(t5, z[7].re, z[6].re, -z[7].re); |
| BF(t6, z[7].im, z[6].im, -z[7].im); |
| |
| BUTTERFLIES(z[0],z[2],z[4],z[6]); |
| TRANSFORM(z[1],z[3],z[5],z[7],RESCALE(M_SQRT1_2),RESCALE(M_SQRT1_2)); |
| } |
| |
| static void fft16(FFTComplex *z) |
| { |
| FFTSample t1, t2, t3, t4, t5, t6; |
| FFTSample cos_16_1 = TX_NAME(ff_cos_16)[1]; |
| FFTSample cos_16_3 = TX_NAME(ff_cos_16)[3]; |
| |
| fft8(z); |
| fft4(z+8); |
| fft4(z+12); |
| |
| TRANSFORM_ZERO(z[0],z[4],z[8],z[12]); |
| TRANSFORM(z[2],z[6],z[10],z[14],RESCALE(M_SQRT1_2),RESCALE(M_SQRT1_2)); |
| TRANSFORM(z[1],z[5],z[9],z[13],cos_16_1,cos_16_3); |
| TRANSFORM(z[3],z[7],z[11],z[15],cos_16_3,cos_16_1); |
| } |
| |
| DECL_FFT(32,16,8) |
| DECL_FFT(64,32,16) |
| DECL_FFT(128,64,32) |
| DECL_FFT(256,128,64) |
| DECL_FFT(512,256,128) |
| #define pass pass_big |
| DECL_FFT(1024,512,256) |
| DECL_FFT(2048,1024,512) |
| DECL_FFT(4096,2048,1024) |
| DECL_FFT(8192,4096,2048) |
| DECL_FFT(16384,8192,4096) |
| DECL_FFT(32768,16384,8192) |
| DECL_FFT(65536,32768,16384) |
| DECL_FFT(131072,65536,32768) |
| |
| static void (* const fft_dispatch[])(FFTComplex*) = { |
| NULL, fft2, fft4, fft8, fft16, fft32, fft64, fft128, fft256, fft512, |
| fft1024, fft2048, fft4096, fft8192, fft16384, fft32768, fft65536, fft131072 |
| }; |
| |
| #define DECL_COMP_FFT(N) \ |
| static void compound_fft_##N##xM(AVTXContext *s, void *_out, \ |
| void *_in, ptrdiff_t stride) \ |
| { \ |
| const int m = s->m, *in_map = s->pfatab, *out_map = in_map + N*m; \ |
| FFTComplex *in = _in; \ |
| FFTComplex *out = _out; \ |
| FFTComplex fft##N##in[N]; \ |
| void (*fftp)(FFTComplex *z) = fft_dispatch[av_log2(m)]; \ |
| \ |
| for (int i = 0; i < m; i++) { \ |
| for (int j = 0; j < N; j++) \ |
| fft##N##in[j] = in[in_map[i*N + j]]; \ |
| fft##N(s->tmp + s->revtab[i], fft##N##in, m); \ |
| } \ |
| \ |
| for (int i = 0; i < N; i++) \ |
| fftp(s->tmp + m*i); \ |
| \ |
| for (int i = 0; i < N*m; i++) \ |
| out[i] = s->tmp[out_map[i]]; \ |
| } |
| |
| DECL_COMP_FFT(3) |
| DECL_COMP_FFT(5) |
| DECL_COMP_FFT(15) |
| |
| static void monolithic_fft(AVTXContext *s, void *_out, void *_in, |
| ptrdiff_t stride) |
| { |
| FFTComplex *in = _in; |
| FFTComplex *out = _out; |
| int m = s->m, mb = av_log2(m); |
| for (int i = 0; i < m; i++) |
| out[s->revtab[i]] = in[i]; |
| fft_dispatch[mb](out); |
| } |
| |
| #define DECL_COMP_IMDCT(N) \ |
| static void compound_imdct_##N##xM(AVTXContext *s, void *_dst, void *_src, \ |
| ptrdiff_t stride) \ |
| { \ |
| FFTComplex fft##N##in[N]; \ |
| FFTComplex *z = _dst, *exp = s->exptab; \ |
| const int m = s->m, len8 = N*m >> 1; \ |
| const int *in_map = s->pfatab, *out_map = in_map + N*m; \ |
| const FFTSample *src = _src, *in1, *in2; \ |
| void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; \ |
| \ |
| stride /= sizeof(*src); /* To convert it from bytes */ \ |
| in1 = src; \ |
| in2 = src + ((N*m*2) - 1) * stride; \ |
| \ |
| for (int i = 0; i < m; i++) { \ |
| for (int j = 0; j < N; j++) { \ |
| const int k = in_map[i*N + j]; \ |
| FFTComplex tmp = { in2[-k*stride], in1[k*stride] }; \ |
| CMUL3(fft##N##in[j], tmp, exp[k >> 1]); \ |
| } \ |
| fft##N(s->tmp + s->revtab[i], fft##N##in, m); \ |
| } \ |
| \ |
| for (int i = 0; i < N; i++) \ |
| fftp(s->tmp + m*i); \ |
| \ |
| for (int i = 0; i < len8; i++) { \ |
| const int i0 = len8 + i, i1 = len8 - i - 1; \ |
| const int s0 = out_map[i0], s1 = out_map[i1]; \ |
| FFTComplex src1 = { s->tmp[s1].im, s->tmp[s1].re }; \ |
| FFTComplex src0 = { s->tmp[s0].im, s->tmp[s0].re }; \ |
| \ |
| CMUL(z[i1].re, z[i0].im, src1.re, src1.im, exp[i1].im, exp[i1].re); \ |
| CMUL(z[i0].re, z[i1].im, src0.re, src0.im, exp[i0].im, exp[i0].re); \ |
| } \ |
| } |
| |
| DECL_COMP_IMDCT(3) |
| DECL_COMP_IMDCT(5) |
| DECL_COMP_IMDCT(15) |
| |
| #define DECL_COMP_MDCT(N) \ |
| static void compound_mdct_##N##xM(AVTXContext *s, void *_dst, void *_src, \ |
| ptrdiff_t stride) \ |
| { \ |
| FFTSample *src = _src, *dst = _dst; \ |
| FFTComplex *exp = s->exptab, tmp, fft##N##in[N]; \ |
| const int m = s->m, len4 = N*m, len3 = len4 * 3, len8 = len4 >> 1; \ |
| const int *in_map = s->pfatab, *out_map = in_map + N*m; \ |
| void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; \ |
| \ |
| stride /= sizeof(*dst); \ |
| \ |
| for (int i = 0; i < m; i++) { /* Folding and pre-reindexing */ \ |
| for (int j = 0; j < N; j++) { \ |
| const int k = in_map[i*N + j]; \ |
| if (k < len4) { \ |
| tmp.re = FOLD(-src[ len4 + k], src[1*len4 - 1 - k]); \ |
| tmp.im = FOLD(-src[ len3 + k], -src[1*len3 - 1 - k]); \ |
| } else { \ |
| tmp.re = FOLD(-src[ len4 + k], -src[5*len4 - 1 - k]); \ |
| tmp.im = FOLD( src[-len4 + k], -src[1*len3 - 1 - k]); \ |
| } \ |
| CMUL(fft##N##in[j].im, fft##N##in[j].re, tmp.re, tmp.im, \ |
| exp[k >> 1].re, exp[k >> 1].im); \ |
| } \ |
| fft##N(s->tmp + s->revtab[i], fft##N##in, m); \ |
| } \ |
| \ |
| for (int i = 0; i < N; i++) \ |
| fftp(s->tmp + m*i); \ |
| \ |
| for (int i = 0; i < len8; i++) { \ |
| const int i0 = len8 + i, i1 = len8 - i - 1; \ |
| const int s0 = out_map[i0], s1 = out_map[i1]; \ |
| FFTComplex src1 = { s->tmp[s1].re, s->tmp[s1].im }; \ |
| FFTComplex src0 = { s->tmp[s0].re, s->tmp[s0].im }; \ |
| \ |
| CMUL(dst[2*i1*stride + stride], dst[2*i0*stride], src0.re, src0.im, \ |
| exp[i0].im, exp[i0].re); \ |
| CMUL(dst[2*i0*stride + stride], dst[2*i1*stride], src1.re, src1.im, \ |
| exp[i1].im, exp[i1].re); \ |
| } \ |
| } |
| |
| DECL_COMP_MDCT(3) |
| DECL_COMP_MDCT(5) |
| DECL_COMP_MDCT(15) |
| |
| static void monolithic_imdct(AVTXContext *s, void *_dst, void *_src, |
| ptrdiff_t stride) |
| { |
| FFTComplex *z = _dst, *exp = s->exptab; |
| const int m = s->m, len8 = m >> 1; |
| const FFTSample *src = _src, *in1, *in2; |
| void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; |
| |
| stride /= sizeof(*src); |
| in1 = src; |
| in2 = src + ((m*2) - 1) * stride; |
| |
| for (int i = 0; i < m; i++) { |
| FFTComplex tmp = { in2[-2*i*stride], in1[2*i*stride] }; |
| CMUL3(z[s->revtab[i]], tmp, exp[i]); |
| } |
| |
| fftp(z); |
| |
| for (int i = 0; i < len8; i++) { |
| const int i0 = len8 + i, i1 = len8 - i - 1; |
| FFTComplex src1 = { z[i1].im, z[i1].re }; |
| FFTComplex src0 = { z[i0].im, z[i0].re }; |
| |
| CMUL(z[i1].re, z[i0].im, src1.re, src1.im, exp[i1].im, exp[i1].re); |
| CMUL(z[i0].re, z[i1].im, src0.re, src0.im, exp[i0].im, exp[i0].re); |
| } |
| } |
| |
| static void monolithic_mdct(AVTXContext *s, void *_dst, void *_src, |
| ptrdiff_t stride) |
| { |
| FFTSample *src = _src, *dst = _dst; |
| FFTComplex *exp = s->exptab, tmp, *z = _dst; |
| const int m = s->m, len4 = m, len3 = len4 * 3, len8 = len4 >> 1; |
| void (*fftp)(FFTComplex *) = fft_dispatch[av_log2(m)]; |
| |
| stride /= sizeof(*dst); |
| |
| for (int i = 0; i < m; i++) { /* Folding and pre-reindexing */ |
| const int k = 2*i; |
| if (k < len4) { |
| tmp.re = FOLD(-src[ len4 + k], src[1*len4 - 1 - k]); |
| tmp.im = FOLD(-src[ len3 + k], -src[1*len3 - 1 - k]); |
| } else { |
| tmp.re = FOLD(-src[ len4 + k], -src[5*len4 - 1 - k]); |
| tmp.im = FOLD( src[-len4 + k], -src[1*len3 - 1 - k]); |
| } |
| CMUL(z[s->revtab[i]].im, z[s->revtab[i]].re, tmp.re, tmp.im, |
| exp[i].re, exp[i].im); |
| } |
| |
| fftp(z); |
| |
| for (int i = 0; i < len8; i++) { |
| const int i0 = len8 + i, i1 = len8 - i - 1; |
| FFTComplex src1 = { z[i1].re, z[i1].im }; |
| FFTComplex src0 = { z[i0].re, z[i0].im }; |
| |
| CMUL(dst[2*i1*stride + stride], dst[2*i0*stride], src0.re, src0.im, |
| exp[i0].im, exp[i0].re); |
| CMUL(dst[2*i0*stride + stride], dst[2*i1*stride], src1.re, src1.im, |
| exp[i1].im, exp[i1].re); |
| } |
| } |
| |
| static int gen_mdct_exptab(AVTXContext *s, int len4, double scale) |
| { |
| const double theta = (scale < 0 ? len4 : 0) + 1.0/8.0; |
| |
| if (!(s->exptab = av_malloc_array(len4, sizeof(*s->exptab)))) |
| return AVERROR(ENOMEM); |
| |
| scale = sqrt(fabs(scale)); |
| for (int i = 0; i < len4; i++) { |
| const double alpha = M_PI_2 * (i + theta) / len4; |
| s->exptab[i].re = RESCALE(cos(alpha) * scale); |
| s->exptab[i].im = RESCALE(sin(alpha) * scale); |
| } |
| |
| return 0; |
| } |
| |
| int TX_NAME(ff_tx_init_mdct_fft)(AVTXContext *s, av_tx_fn *tx, |
| enum AVTXType type, int inv, int len, |
| const void *scale, uint64_t flags) |
| { |
| const int is_mdct = ff_tx_type_is_mdct(type); |
| int err, n = 1, m = 1, max_ptwo = 1 << (FF_ARRAY_ELEMS(fft_dispatch) - 1); |
| |
| if (is_mdct) |
| len >>= 1; |
| |
| #define CHECK_FACTOR(DST, FACTOR, SRC) \ |
| if (DST == 1 && !(SRC % FACTOR)) { \ |
| DST = FACTOR; \ |
| SRC /= FACTOR; \ |
| } |
| CHECK_FACTOR(n, 15, len) |
| CHECK_FACTOR(n, 5, len) |
| CHECK_FACTOR(n, 3, len) |
| #undef CHECK_FACTOR |
| |
| /* len must be a power of two now */ |
| if (!(len & (len - 1)) && len >= 2 && len <= max_ptwo) { |
| m = len; |
| len = 1; |
| } |
| |
| s->n = n; |
| s->m = m; |
| s->inv = inv; |
| s->type = type; |
| |
| /* Filter out direct 3, 5 and 15 transforms, too niche */ |
| if (len > 1 || m == 1) { |
| av_log(NULL, AV_LOG_ERROR, "Unsupported transform size: n = %i, " |
| "m = %i, residual = %i!\n", n, m, len); |
| return AVERROR(EINVAL); |
| } else if (n > 1 && m > 1) { /* 2D transform case */ |
| if ((err = ff_tx_gen_compound_mapping(s))) |
| return err; |
| if (!(s->tmp = av_malloc(n*m*sizeof(*s->tmp)))) |
| return AVERROR(ENOMEM); |
| *tx = n == 3 ? compound_fft_3xM : |
| n == 5 ? compound_fft_5xM : |
| compound_fft_15xM; |
| if (is_mdct) |
| *tx = n == 3 ? inv ? compound_imdct_3xM : compound_mdct_3xM : |
| n == 5 ? inv ? compound_imdct_5xM : compound_mdct_5xM : |
| inv ? compound_imdct_15xM : compound_mdct_15xM; |
| } else { /* Direct transform case */ |
| *tx = monolithic_fft; |
| if (is_mdct) |
| *tx = inv ? monolithic_imdct : monolithic_mdct; |
| } |
| |
| if (n != 1) |
| init_cos_tabs(0); |
| if (m != 1) { |
| ff_tx_gen_ptwo_revtab(s); |
| for (int i = 4; i <= av_log2(m); i++) |
| init_cos_tabs(i); |
| } |
| |
| if (is_mdct) |
| return gen_mdct_exptab(s, n*m, *((SCALE_TYPE *)scale)); |
| |
| return 0; |
| } |
