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			315 lines
		
	
	
	
		
			9.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			315 lines
		
	
	
	
		
			9.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * AAC Spectral Band Replication decoding functions
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|  * Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
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|  * Copyright (c) 2009-2010 Alex Converse <alex.converse@gmail.com>
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  *
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|  * Note: Rounding-to-nearest used unless otherwise stated
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|  *
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|  */
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| 
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| #define USE_FIXED 1
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| 
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| #include "aac.h"
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| #include "config.h"
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| #include "libavutil/attributes.h"
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| #include "libavutil/intfloat.h"
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| #include "sbrdsp.h"
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| 
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| static SoftFloat sbr_sum_square_c(int (*x)[2], int n)
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| {
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|     SoftFloat ret;
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|     uint64_t accu = 0, round;
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|     uint64_t accu0 = 0, accu1 = 0, accu2 = 0, accu3 = 0;
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|     int i, nz, nz0;
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|     unsigned u;
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| 
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|     nz = 0;
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|     for (i = 0; i < n; i += 2) {
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|         accu0 += (int64_t)x[i + 0][0] * x[i + 0][0];
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|         accu1 += (int64_t)x[i + 0][1] * x[i + 0][1];
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|         accu2 += (int64_t)x[i + 1][0] * x[i + 1][0];
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|         accu3 += (int64_t)x[i + 1][1] * x[i + 1][1];
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|         if ((accu0|accu1|accu2|accu3) > UINT64_MAX - INT32_MIN*(int64_t)INT32_MIN || i+2>=n) {
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|             accu0 >>= nz;
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|             accu1 >>= nz;
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|             accu2 >>= nz;
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|             accu3 >>= nz;
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|             while ((accu0|accu1|accu2|accu3) > (UINT64_MAX - accu) >> 2) {
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|                 accu0 >>= 1;
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|                 accu1 >>= 1;
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|                 accu2 >>= 1;
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|                 accu3 >>= 1;
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|                 accu  >>= 1;
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|                 nz ++;
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|             }
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|             accu += accu0 + accu1 + accu2 + accu3;
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|             accu0 = accu1 = accu2 = accu3 = 0;
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|         }
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|     }
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| 
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|     nz0 = 15 - nz;
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| 
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|     u = accu >> 32;
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|     if (u) {
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|         nz = 33;
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|         while (u < 0x80000000U) {
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|             u <<= 1;
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|             nz--;
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|         }
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|     } else
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|         nz = 1;
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| 
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|     round = 1ULL << (nz-1);
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|     u = ((accu + round) >> nz);
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|     u >>= 1;
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|     ret = av_int2sf(u, nz0 - nz);
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| 
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|     return ret;
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| }
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| 
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| static void sbr_neg_odd_64_c(int *x)
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| {
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|     int i;
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|     for (i = 1; i < 64; i += 2)
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|         x[i] = -x[i];
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| }
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| 
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| static void sbr_qmf_pre_shuffle_c(int *z)
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| {
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|     int k;
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|     z[64] = z[0];
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|     z[65] = z[1];
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|     for (k = 1; k < 32; k++) {
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|         z[64+2*k  ] = -z[64 - k];
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|         z[64+2*k+1] =  z[ k + 1];
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|     }
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| }
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| 
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| static void sbr_qmf_post_shuffle_c(int W[32][2], const int *z)
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| {
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|     int k;
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|     for (k = 0; k < 32; k++) {
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|         W[k][0] = -z[63-k];
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|         W[k][1] = z[k];
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|     }
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| }
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| 
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| static void sbr_qmf_deint_neg_c(int *v, const int *src)
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| {
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|     int i;
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|     for (i = 0; i < 32; i++) {
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|         v[     i] = ( src[63 - 2*i    ] + 0x10) >> 5;
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|         v[63 - i] = (-src[63 - 2*i - 1] + 0x10) >> 5;
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|     }
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| }
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| 
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| static av_always_inline SoftFloat autocorr_calc(int64_t accu)
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| {
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|         int nz, mant, expo;
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|         unsigned round;
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|         int i = (int)(accu >> 32);
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|         if (i == 0) {
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|             nz = 1;
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|         } else {
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|             nz = 0;
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|             while (FFABS(i) < 0x40000000) {
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|                 i *= 2;
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|                 nz++;
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|             }
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|             nz = 32-nz;
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|         }
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| 
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|         round = 1U << (nz-1);
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|         mant = (int)((accu + round) >> nz);
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|         mant = (mant + 0x40LL)>>7;
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|         mant *= 64;
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|         expo = nz + 15;
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|         return av_int2sf(mant, 30 - expo);
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| }
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| 
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| static av_always_inline void autocorrelate(const int x[40][2], SoftFloat phi[3][2][2], int lag)
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| {
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|     int i;
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|     int64_t real_sum, imag_sum;
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|     int64_t accu_re = 0, accu_im = 0;
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| 
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|     if (lag) {
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|         for (i = 1; i < 38; i++) {
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|             accu_re += (uint64_t)x[i][0] * x[i+lag][0];
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|             accu_re += (uint64_t)x[i][1] * x[i+lag][1];
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|             accu_im += (uint64_t)x[i][0] * x[i+lag][1];
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|             accu_im -= (uint64_t)x[i][1] * x[i+lag][0];
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|         }
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| 
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|         real_sum = accu_re;
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|         imag_sum = accu_im;
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| 
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|         accu_re += (uint64_t)x[ 0][0] * x[lag][0];
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|         accu_re += (uint64_t)x[ 0][1] * x[lag][1];
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|         accu_im += (uint64_t)x[ 0][0] * x[lag][1];
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|         accu_im -= (uint64_t)x[ 0][1] * x[lag][0];
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| 
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|         phi[2-lag][1][0] = autocorr_calc(accu_re);
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|         phi[2-lag][1][1] = autocorr_calc(accu_im);
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| 
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|         if (lag == 1) {
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|             accu_re = real_sum;
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|             accu_im = imag_sum;
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|             accu_re += (uint64_t)x[38][0] * x[39][0];
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|             accu_re += (uint64_t)x[38][1] * x[39][1];
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|             accu_im += (uint64_t)x[38][0] * x[39][1];
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|             accu_im -= (uint64_t)x[38][1] * x[39][0];
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| 
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|             phi[0][0][0] = autocorr_calc(accu_re);
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|             phi[0][0][1] = autocorr_calc(accu_im);
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|         }
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|     } else {
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|         for (i = 1; i < 38; i++) {
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|             accu_re += (uint64_t)x[i][0] * x[i][0];
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|             accu_re += (uint64_t)x[i][1] * x[i][1];
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|         }
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|         real_sum = accu_re;
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|         accu_re += (uint64_t)x[ 0][0] * x[ 0][0];
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|         accu_re += (uint64_t)x[ 0][1] * x[ 0][1];
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| 
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|         phi[2][1][0] = autocorr_calc(accu_re);
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| 
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|         accu_re = real_sum;
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|         accu_re += (uint64_t)x[38][0] * x[38][0];
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|         accu_re += (uint64_t)x[38][1] * x[38][1];
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| 
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|         phi[1][0][0] = autocorr_calc(accu_re);
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|     }
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| }
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| 
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| static void sbr_autocorrelate_c(const int x[40][2], SoftFloat phi[3][2][2])
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| {
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|     autocorrelate(x, phi, 0);
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|     autocorrelate(x, phi, 1);
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|     autocorrelate(x, phi, 2);
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| }
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| 
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| static void sbr_hf_gen_c(int (*X_high)[2], const int (*X_low)[2],
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|                        const int alpha0[2], const int alpha1[2],
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|                        int bw, int start, int end)
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| {
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|     int alpha[4];
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|     int i;
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|     int64_t accu;
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| 
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|     accu = (int64_t)alpha0[0] * bw;
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|     alpha[2] = (int)((accu + 0x40000000) >> 31);
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|     accu = (int64_t)alpha0[1] * bw;
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|     alpha[3] = (int)((accu + 0x40000000) >> 31);
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|     accu = (int64_t)bw * bw;
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|     bw = (int)((accu + 0x40000000) >> 31);
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|     accu = (int64_t)alpha1[0] * bw;
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|     alpha[0] = (int)((accu + 0x40000000) >> 31);
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|     accu = (int64_t)alpha1[1] * bw;
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|     alpha[1] = (int)((accu + 0x40000000) >> 31);
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| 
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|     for (i = start; i < end; i++) {
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|         accu  = (int64_t)X_low[i][0] * 0x20000000;
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|         accu += (int64_t)X_low[i - 2][0] * alpha[0];
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|         accu -= (int64_t)X_low[i - 2][1] * alpha[1];
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|         accu += (int64_t)X_low[i - 1][0] * alpha[2];
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|         accu -= (int64_t)X_low[i - 1][1] * alpha[3];
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|         X_high[i][0] = (int)((accu + 0x10000000) >> 29);
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| 
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|         accu  = (int64_t)X_low[i][1] * 0x20000000;
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|         accu += (int64_t)X_low[i - 2][1] * alpha[0];
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|         accu += (int64_t)X_low[i - 2][0] * alpha[1];
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|         accu += (int64_t)X_low[i - 1][1] * alpha[2];
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|         accu += (int64_t)X_low[i - 1][0] * alpha[3];
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|         X_high[i][1] = (int)((accu + 0x10000000) >> 29);
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|     }
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| }
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| 
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| static void sbr_hf_g_filt_c(int (*Y)[2], const int (*X_high)[40][2],
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|                           const SoftFloat *g_filt, int m_max, intptr_t ixh)
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| {
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|     int m;
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|     int64_t accu;
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| 
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|     for (m = 0; m < m_max; m++) {
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|         if (22 - g_filt[m].exp < 61) {
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|             int64_t r = 1LL << (22-g_filt[m].exp);
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|             accu = (int64_t)X_high[m][ixh][0] * ((g_filt[m].mant + 0x40)>>7);
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|             Y[m][0] = (int)((accu + r) >> (23-g_filt[m].exp));
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| 
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|             accu = (int64_t)X_high[m][ixh][1] * ((g_filt[m].mant + 0x40)>>7);
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|             Y[m][1] = (int)((accu + r) >> (23-g_filt[m].exp));
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|         }
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|     }
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| }
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| 
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| static av_always_inline int sbr_hf_apply_noise(int (*Y)[2],
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|                                                 const SoftFloat *s_m,
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|                                                 const SoftFloat *q_filt,
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|                                                 int noise,
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|                                                 int phi_sign0,
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|                                                 int phi_sign1,
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|                                                 int m_max)
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| {
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|     int m;
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| 
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|     for (m = 0; m < m_max; m++) {
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|         unsigned y0 = Y[m][0];
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|         unsigned y1 = Y[m][1];
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|         noise = (noise + 1) & 0x1ff;
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|         if (s_m[m].mant) {
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|             int shift, round;
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| 
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|             shift = 22 - s_m[m].exp;
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|             if (shift < 1) {
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|                 av_log(NULL, AV_LOG_ERROR, "Overflow in sbr_hf_apply_noise, shift=%d\n", shift);
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|                 return AVERROR(ERANGE);
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|             } else if (shift < 30) {
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|                 round = 1 << (shift-1);
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|                 y0 += (s_m[m].mant * phi_sign0 + round) >> shift;
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|                 y1 += (s_m[m].mant * phi_sign1 + round) >> shift;
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|             }
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|         } else {
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|             int shift, round, tmp;
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|             int64_t accu;
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| 
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|             shift = 22 - q_filt[m].exp;
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|             if (shift < 1) {
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|                 av_log(NULL, AV_LOG_ERROR, "Overflow in sbr_hf_apply_noise, shift=%d\n", shift);
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|                 return AVERROR(ERANGE);
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|             } else if (shift < 30) {
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|                 round = 1 << (shift-1);
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| 
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|                 accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][0];
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|                 tmp = (int)((accu + 0x40000000) >> 31);
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|                 y0 += (tmp + round) >> shift;
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| 
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|                 accu = (int64_t)q_filt[m].mant * ff_sbr_noise_table_fixed[noise][1];
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|                 tmp = (int)((accu + 0x40000000) >> 31);
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|                 y1 += (tmp + round) >> shift;
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|             }
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|         }
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|         Y[m][0] = y0;
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|         Y[m][1] = y1;
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|         phi_sign1 = -phi_sign1;
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|     }
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|     return 0;
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| }
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| 
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| #include "sbrdsp_template.c"
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