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ffmpeg/libavcodec/x86/fdct.c

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/*
* MMX optimized forward DCT
* The gcc porting is Copyright (c) 2001 Fabrice Bellard.
* cleanup/optimizations are Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
* SSE2 optimization is Copyright (c) 2004 Denes Balatoni.
*
* from fdctam32.c - AP922 MMX(3D-Now) forward-DCT
*
* Intel Application Note AP-922 - fast, precise implementation of DCT
* http://developer.intel.com/vtune/cbts/appnotes.htm
*
* Also of inspiration:
* a page about fdct at http://www.geocities.com/ssavekar/dct.htm
* Skal's fdct at http://skal.planet-d.net/coding/dct.html
*
* This file is part of Libav.
*
* Libav 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,
* 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
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include "libavutil/common.h"
#include "libavutil/x86/asm.h"
#include "libavcodec/dct.h"
#if HAVE_MMX_INLINE
//////////////////////////////////////////////////////////////////////
//
// constants for the forward DCT
// -----------------------------
//
// Be sure to check that your compiler is aligning all constants to QWORD
// (8-byte) memory boundaries! Otherwise the unaligned memory access will
// severely stall MMX execution.
//
//////////////////////////////////////////////////////////////////////
#define BITS_FRW_ACC 3 //; 2 or 3 for accuracy
#define SHIFT_FRW_COL BITS_FRW_ACC
#define SHIFT_FRW_ROW (BITS_FRW_ACC + 17 - 3)
#define RND_FRW_ROW (1 << (SHIFT_FRW_ROW-1))
//#define RND_FRW_COL (1 << (SHIFT_FRW_COL-1))
#define X8(x) x,x,x,x,x,x,x,x
//concatenated table, for forward DCT transformation
DECLARE_ALIGNED(16, static const int16_t, fdct_tg_all_16)[24] = {
X8(13036), // tg * (2<<16) + 0.5
X8(27146), // tg * (2<<16) + 0.5
X8(-21746) // tg * (2<<16) + 0.5
};
DECLARE_ALIGNED(16, static const int16_t, ocos_4_16)[8] = {
X8(23170) //cos * (2<<15) + 0.5
};
DECLARE_ALIGNED(16, static const int16_t, fdct_one_corr)[8] = { X8(1) };
DECLARE_ALIGNED(8, static const int32_t, fdct_r_row)[2] = {RND_FRW_ROW, RND_FRW_ROW };
static struct
{
DECLARE_ALIGNED(16, const int32_t, fdct_r_row_sse2)[4];
} fdct_r_row_sse2 =
{{
RND_FRW_ROW, RND_FRW_ROW, RND_FRW_ROW, RND_FRW_ROW
}};
//DECLARE_ALIGNED(16, static const long, fdct_r_row_sse2)[4] = {RND_FRW_ROW, RND_FRW_ROW, RND_FRW_ROW, RND_FRW_ROW};
DECLARE_ALIGNED(8, static const int16_t, tab_frw_01234567)[] = { // forward_dct coeff table
16384, 16384, 22725, 19266,
16384, 16384, 12873, 4520,
21407, 8867, 19266, -4520,
-8867, -21407, -22725, -12873,
16384, -16384, 12873, -22725,
-16384, 16384, 4520, 19266,
8867, -21407, 4520, -12873,
21407, -8867, 19266, -22725,
22725, 22725, 31521, 26722,
22725, 22725, 17855, 6270,
29692, 12299, 26722, -6270,
-12299, -29692, -31521, -17855,
22725, -22725, 17855, -31521,
-22725, 22725, 6270, 26722,
12299, -29692, 6270, -17855,
29692, -12299, 26722, -31521,
21407, 21407, 29692, 25172,
21407, 21407, 16819, 5906,
27969, 11585, 25172, -5906,
-11585, -27969, -29692, -16819,
21407, -21407, 16819, -29692,
-21407, 21407, 5906, 25172,
11585, -27969, 5906, -16819,
27969, -11585, 25172, -29692,
19266, 19266, 26722, 22654,
19266, 19266, 15137, 5315,
25172, 10426, 22654, -5315,
-10426, -25172, -26722, -15137,
19266, -19266, 15137, -26722,
-19266, 19266, 5315, 22654,
10426, -25172, 5315, -15137,
25172, -10426, 22654, -26722,
16384, 16384, 22725, 19266,
16384, 16384, 12873, 4520,
21407, 8867, 19266, -4520,
-8867, -21407, -22725, -12873,
16384, -16384, 12873, -22725,
-16384, 16384, 4520, 19266,
8867, -21407, 4520, -12873,
21407, -8867, 19266, -22725,
19266, 19266, 26722, 22654,
19266, 19266, 15137, 5315,
25172, 10426, 22654, -5315,
-10426, -25172, -26722, -15137,
19266, -19266, 15137, -26722,
-19266, 19266, 5315, 22654,
10426, -25172, 5315, -15137,
25172, -10426, 22654, -26722,
21407, 21407, 29692, 25172,
21407, 21407, 16819, 5906,
27969, 11585, 25172, -5906,
-11585, -27969, -29692, -16819,
21407, -21407, 16819, -29692,
-21407, 21407, 5906, 25172,
11585, -27969, 5906, -16819,
27969, -11585, 25172, -29692,
22725, 22725, 31521, 26722,
22725, 22725, 17855, 6270,
29692, 12299, 26722, -6270,
-12299, -29692, -31521, -17855,
22725, -22725, 17855, -31521,
-22725, 22725, 6270, 26722,
12299, -29692, 6270, -17855,
29692, -12299, 26722, -31521,
};
static struct
{
DECLARE_ALIGNED(16, const int16_t, tab_frw_01234567_sse2)[256];
} tab_frw_01234567_sse2 =
{{
//DECLARE_ALIGNED(16, static const int16_t, tab_frw_01234567_sse2)[] = { // forward_dct coeff table
#define TABLE_SSE2 C4, C4, C1, C3, -C6, -C2, -C1, -C5, \
C4, C4, C5, C7, C2, C6, C3, -C7, \
-C4, C4, C7, C3, C6, -C2, C7, -C5, \
C4, -C4, C5, -C1, C2, -C6, C3, -C1,
// c1..c7 * cos(pi/4) * 2^15
#define C1 22725
#define C2 21407
#define C3 19266
#define C4 16384
#define C5 12873
#define C6 8867
#define C7 4520
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 31521
#define C2 29692
#define C3 26722
#define C4 22725
#define C5 17855
#define C6 12299
#define C7 6270
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 29692
#define C2 27969
#define C3 25172
#define C4 21407
#define C5 16819
#define C6 11585
#define C7 5906
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 26722
#define C2 25172
#define C3 22654
#define C4 19266
#define C5 15137
#define C6 10426
#define C7 5315
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 22725
#define C2 21407
#define C3 19266
#define C4 16384
#define C5 12873
#define C6 8867
#define C7 4520
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 26722
#define C2 25172
#define C3 22654
#define C4 19266
#define C5 15137
#define C6 10426
#define C7 5315
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 29692
#define C2 27969
#define C3 25172
#define C4 21407
#define C5 16819
#define C6 11585
#define C7 5906
TABLE_SSE2
#undef C1
#undef C2
#undef C3
#undef C4
#undef C5
#undef C6
#undef C7
#define C1 31521
#define C2 29692
#define C3 26722
#define C4 22725
#define C5 17855
#define C6 12299
#define C7 6270
TABLE_SSE2
}};
#define S(s) AV_TOSTRING(s) //AV_STRINGIFY is too long
#define FDCT_COL(cpu, mm, mov)\
static av_always_inline void fdct_col_##cpu(const int16_t *in, int16_t *out, int offset)\
{\
__asm__ volatile (\
#mov" 16(%0), %%"#mm"0 \n\t" \
#mov" 96(%0), %%"#mm"1 \n\t" \
#mov" %%"#mm"0, %%"#mm"2 \n\t" \
#mov" 32(%0), %%"#mm"3 \n\t" \
"paddsw %%"#mm"1, %%"#mm"0 \n\t" \
#mov" 80(%0), %%"#mm"4 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"0 \n\t" \
#mov" (%0), %%"#mm"5 \n\t" \
"paddsw %%"#mm"3, %%"#mm"4 \n\t" \
"paddsw 112(%0), %%"#mm"5 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"4 \n\t" \
#mov" %%"#mm"0, %%"#mm"6 \n\t" \
"psubsw %%"#mm"1, %%"#mm"2 \n\t" \
#mov" 16(%1), %%"#mm"1 \n\t" \
"psubsw %%"#mm"4, %%"#mm"0 \n\t" \
#mov" 48(%0), %%"#mm"7 \n\t" \
"pmulhw %%"#mm"0, %%"#mm"1 \n\t" \
"paddsw 64(%0), %%"#mm"7 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"5 \n\t" \
"paddsw %%"#mm"4, %%"#mm"6 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"7 \n\t" \
#mov" %%"#mm"5, %%"#mm"4 \n\t" \
"psubsw %%"#mm"7, %%"#mm"5 \n\t" \
"paddsw %%"#mm"5, %%"#mm"1 \n\t" \
"paddsw %%"#mm"7, %%"#mm"4 \n\t" \
"por (%2), %%"#mm"1 \n\t" \
"psllw $"S(SHIFT_FRW_COL)"+1, %%"#mm"2 \n\t" \
"pmulhw 16(%1), %%"#mm"5 \n\t" \
#mov" %%"#mm"4, %%"#mm"7 \n\t" \
"psubsw 80(%0), %%"#mm"3 \n\t" \
"psubsw %%"#mm"6, %%"#mm"4 \n\t" \
#mov" %%"#mm"1, 32(%3) \n\t" \
"paddsw %%"#mm"6, %%"#mm"7 \n\t" \
#mov" 48(%0), %%"#mm"1 \n\t" \
"psllw $"S(SHIFT_FRW_COL)"+1, %%"#mm"3 \n\t" \
"psubsw 64(%0), %%"#mm"1 \n\t" \
#mov" %%"#mm"2, %%"#mm"6 \n\t" \
#mov" %%"#mm"4, 64(%3) \n\t" \
"paddsw %%"#mm"3, %%"#mm"2 \n\t" \
"pmulhw (%4), %%"#mm"2 \n\t" \
"psubsw %%"#mm"3, %%"#mm"6 \n\t" \
"pmulhw (%4), %%"#mm"6 \n\t" \
"psubsw %%"#mm"0, %%"#mm"5 \n\t" \
"por (%2), %%"#mm"5 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"1 \n\t" \
"por (%2), %%"#mm"2 \n\t" \
#mov" %%"#mm"1, %%"#mm"4 \n\t" \
#mov" (%0), %%"#mm"3 \n\t" \
"paddsw %%"#mm"6, %%"#mm"1 \n\t" \
"psubsw 112(%0), %%"#mm"3 \n\t" \
"psubsw %%"#mm"6, %%"#mm"4 \n\t" \
#mov" (%1), %%"#mm"0 \n\t" \
"psllw $"S(SHIFT_FRW_COL)", %%"#mm"3 \n\t" \
#mov" 32(%1), %%"#mm"6 \n\t" \
"pmulhw %%"#mm"1, %%"#mm"0 \n\t" \
#mov" %%"#mm"7, (%3) \n\t" \
"pmulhw %%"#mm"4, %%"#mm"6 \n\t" \
#mov" %%"#mm"5, 96(%3) \n\t" \
#mov" %%"#mm"3, %%"#mm"7 \n\t" \
#mov" 32(%1), %%"#mm"5 \n\t" \
"psubsw %%"#mm"2, %%"#mm"7 \n\t" \
"paddsw %%"#mm"2, %%"#mm"3 \n\t" \
"pmulhw %%"#mm"7, %%"#mm"5 \n\t" \
"paddsw %%"#mm"3, %%"#mm"0 \n\t" \
"paddsw %%"#mm"4, %%"#mm"6 \n\t" \
"pmulhw (%1), %%"#mm"3 \n\t" \
"por (%2), %%"#mm"0 \n\t" \
"paddsw %%"#mm"7, %%"#mm"5 \n\t" \
"psubsw %%"#mm"6, %%"#mm"7 \n\t" \
#mov" %%"#mm"0, 16(%3) \n\t" \
"paddsw %%"#mm"4, %%"#mm"5 \n\t" \
#mov" %%"#mm"7, 48(%3) \n\t" \
"psubsw %%"#mm"1, %%"#mm"3 \n\t" \
#mov" %%"#mm"5, 80(%3) \n\t" \
#mov" %%"#mm"3, 112(%3) \n\t" \
: \
: "r" (in + offset), "r" (fdct_tg_all_16), "r" (fdct_one_corr), \
"r" (out + offset), "r" (ocos_4_16)); \
}
FDCT_COL(mmx, mm, movq)
FDCT_COL(sse2, xmm, movdqa)
static av_always_inline void fdct_row_sse2(const int16_t *in, int16_t *out)
{
__asm__ volatile(
#define FDCT_ROW_SSE2_H1(i,t) \
"movq " #i "(%0), %%xmm2 \n\t" \
"movq " #i "+8(%0), %%xmm0 \n\t" \
"movdqa " #t "+32(%1), %%xmm3 \n\t" \
"movdqa " #t "+48(%1), %%xmm7 \n\t" \
"movdqa " #t "(%1), %%xmm4 \n\t" \
"movdqa " #t "+16(%1), %%xmm5 \n\t"
#define FDCT_ROW_SSE2_H2(i,t) \
"movq " #i "(%0), %%xmm2 \n\t" \
"movq " #i "+8(%0), %%xmm0 \n\t" \
"movdqa " #t "+32(%1), %%xmm3 \n\t" \
"movdqa " #t "+48(%1), %%xmm7 \n\t"
#define FDCT_ROW_SSE2(i) \
"movq %%xmm2, %%xmm1 \n\t" \
"pshuflw $27, %%xmm0, %%xmm0 \n\t" \
"paddsw %%xmm0, %%xmm1 \n\t" \
"psubsw %%xmm0, %%xmm2 \n\t" \
"punpckldq %%xmm2, %%xmm1 \n\t" \
"pshufd $78, %%xmm1, %%xmm2 \n\t" \
"pmaddwd %%xmm2, %%xmm3 \n\t" \
"pmaddwd %%xmm1, %%xmm7 \n\t" \
"pmaddwd %%xmm5, %%xmm2 \n\t" \
"pmaddwd %%xmm4, %%xmm1 \n\t" \
"paddd %%xmm7, %%xmm3 \n\t" \
"paddd %%xmm2, %%xmm1 \n\t" \
"paddd %%xmm6, %%xmm3 \n\t" \
"paddd %%xmm6, %%xmm1 \n\t" \
"psrad %3, %%xmm3 \n\t" \
"psrad %3, %%xmm1 \n\t" \
"packssdw %%xmm3, %%xmm1 \n\t" \
"movdqa %%xmm1, " #i "(%4) \n\t"
"movdqa (%2), %%xmm6 \n\t"
FDCT_ROW_SSE2_H1(0,0)
FDCT_ROW_SSE2(0)
FDCT_ROW_SSE2_H2(64,0)
FDCT_ROW_SSE2(64)
FDCT_ROW_SSE2_H1(16,64)
FDCT_ROW_SSE2(16)
FDCT_ROW_SSE2_H2(112,64)
FDCT_ROW_SSE2(112)
FDCT_ROW_SSE2_H1(32,128)
FDCT_ROW_SSE2(32)
FDCT_ROW_SSE2_H2(96,128)
FDCT_ROW_SSE2(96)
FDCT_ROW_SSE2_H1(48,192)
FDCT_ROW_SSE2(48)
FDCT_ROW_SSE2_H2(80,192)
FDCT_ROW_SSE2(80)
:
: "r" (in), "r" (tab_frw_01234567_sse2.tab_frw_01234567_sse2),
"r" (fdct_r_row_sse2.fdct_r_row_sse2), "i" (SHIFT_FRW_ROW), "r" (out)
XMM_CLOBBERS_ONLY("%xmm0", "%xmm1", "%xmm2", "%xmm3",
"%xmm4", "%xmm5", "%xmm6", "%xmm7")
);
}
static av_always_inline void fdct_row_mmxext(const int16_t *in, int16_t *out,
const int16_t *table)
{
__asm__ volatile (
"pshufw $0x1B, 8(%0), %%mm5 \n\t"
"movq (%0), %%mm0 \n\t"
"movq %%mm0, %%mm1 \n\t"
"paddsw %%mm5, %%mm0 \n\t"
"psubsw %%mm5, %%mm1 \n\t"
"movq %%mm0, %%mm2 \n\t"
"punpckldq %%mm1, %%mm0 \n\t"
"punpckhdq %%mm1, %%mm2 \n\t"
"movq (%1), %%mm1 \n\t"
"movq 8(%1), %%mm3 \n\t"
"movq 16(%1), %%mm4 \n\t"
"movq 24(%1), %%mm5 \n\t"
"movq 32(%1), %%mm6 \n\t"
"movq 40(%1), %%mm7 \n\t"
"pmaddwd %%mm0, %%mm1 \n\t"
"pmaddwd %%mm2, %%mm3 \n\t"
"pmaddwd %%mm0, %%mm4 \n\t"
"pmaddwd %%mm2, %%mm5 \n\t"
"pmaddwd %%mm0, %%mm6 \n\t"
"pmaddwd %%mm2, %%mm7 \n\t"
"pmaddwd 48(%1), %%mm0 \n\t"
"pmaddwd 56(%1), %%mm2 \n\t"
"paddd %%mm1, %%mm3 \n\t"
"paddd %%mm4, %%mm5 \n\t"
"paddd %%mm6, %%mm7 \n\t"
"paddd %%mm0, %%mm2 \n\t"
"movq (%2), %%mm0 \n\t"
"paddd %%mm0, %%mm3 \n\t"
"paddd %%mm0, %%mm5 \n\t"
"paddd %%mm0, %%mm7 \n\t"
"paddd %%mm0, %%mm2 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm3 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm5 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm7 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm2 \n\t"
"packssdw %%mm5, %%mm3 \n\t"
"packssdw %%mm2, %%mm7 \n\t"
"movq %%mm3, (%3) \n\t"
"movq %%mm7, 8(%3) \n\t"
:
: "r" (in), "r" (table), "r" (fdct_r_row), "r" (out));
}
static av_always_inline void fdct_row_mmx(const int16_t *in, int16_t *out, const int16_t *table)
{
//FIXME reorder (I do not have an old MMX-only CPU here to benchmark ...)
__asm__ volatile(
"movd 12(%0), %%mm1 \n\t"
"punpcklwd 8(%0), %%mm1 \n\t"
"movq %%mm1, %%mm2 \n\t"
"psrlq $0x20, %%mm1 \n\t"
"movq 0(%0), %%mm0 \n\t"
"punpcklwd %%mm2, %%mm1 \n\t"
"movq %%mm0, %%mm5 \n\t"
"paddsw %%mm1, %%mm0 \n\t"
"psubsw %%mm1, %%mm5 \n\t"
"movq %%mm0, %%mm2 \n\t"
"punpckldq %%mm5, %%mm0 \n\t"
"punpckhdq %%mm5, %%mm2 \n\t"
"movq 0(%1), %%mm1 \n\t"
"movq 8(%1), %%mm3 \n\t"
"movq 16(%1), %%mm4 \n\t"
"movq 24(%1), %%mm5 \n\t"
"movq 32(%1), %%mm6 \n\t"
"movq 40(%1), %%mm7 \n\t"
"pmaddwd %%mm0, %%mm1 \n\t"
"pmaddwd %%mm2, %%mm3 \n\t"
"pmaddwd %%mm0, %%mm4 \n\t"
"pmaddwd %%mm2, %%mm5 \n\t"
"pmaddwd %%mm0, %%mm6 \n\t"
"pmaddwd %%mm2, %%mm7 \n\t"
"pmaddwd 48(%1), %%mm0 \n\t"
"pmaddwd 56(%1), %%mm2 \n\t"
"paddd %%mm1, %%mm3 \n\t"
"paddd %%mm4, %%mm5 \n\t"
"paddd %%mm6, %%mm7 \n\t"
"paddd %%mm0, %%mm2 \n\t"
"movq (%2), %%mm0 \n\t"
"paddd %%mm0, %%mm3 \n\t"
"paddd %%mm0, %%mm5 \n\t"
"paddd %%mm0, %%mm7 \n\t"
"paddd %%mm0, %%mm2 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm3 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm5 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm7 \n\t"
"psrad $"S(SHIFT_FRW_ROW)", %%mm2 \n\t"
"packssdw %%mm5, %%mm3 \n\t"
"packssdw %%mm2, %%mm7 \n\t"
"movq %%mm3, 0(%3) \n\t"
"movq %%mm7, 8(%3) \n\t"
:
: "r" (in), "r" (table), "r" (fdct_r_row), "r" (out));
}
void ff_fdct_mmx(int16_t *block)
{
DECLARE_ALIGNED(8, int64_t, align_tmp)[16];
int16_t * block1= (int16_t*)align_tmp;
const int16_t *table= tab_frw_01234567;
int i;
fdct_col_mmx(block, block1, 0);
fdct_col_mmx(block, block1, 4);
for(i=8;i>0;i--) {
fdct_row_mmx(block1, block, table);
block1 += 8;
table += 32;
block += 8;
}
}
#endif /* HAVE_MMX_INLINE */
#if HAVE_MMXEXT_INLINE
void ff_fdct_mmxext(int16_t *block)
{
DECLARE_ALIGNED(8, int64_t, align_tmp)[16];
int16_t *block1= (int16_t*)align_tmp;
const int16_t *table= tab_frw_01234567;
int i;
fdct_col_mmx(block, block1, 0);
fdct_col_mmx(block, block1, 4);
for(i=8;i>0;i--) {
fdct_row_mmxext(block1, block, table);
block1 += 8;
table += 32;
block += 8;
}
}
#endif /* HAVE_MMXEXT_INLINE */
#if HAVE_SSE2_INLINE
void ff_fdct_sse2(int16_t *block)
{
DECLARE_ALIGNED(16, int64_t, align_tmp)[16];
int16_t * const block1= (int16_t*)align_tmp;
fdct_col_sse2(block, block1, 0);
fdct_row_sse2(block1, block);
}
#endif /* HAVE_SSE2_INLINE */
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