ffmpeg / libavcodec / acelp_vectors.h @ 2912e87a
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/*


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* adaptive and fixed codebook vector operations for ACELPbased codecs

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*

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* Copyright (c) 2008 Vladimir Voroshilov

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*

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* This file is part of Libav.

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*

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* Libav 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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* Libav 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 Libav; if not, write to the Free Software

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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 021101301 USA

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*/

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#ifndef AVCODEC_ACELP_VECTORS_H

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#define AVCODEC_ACELP_VECTORS_H

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#include <stdint.h> 
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/** Sparse representation for the algebraic codebook (fixed) vector */

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typedef struct { 
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int n;

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int x[10]; 
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float y[10]; 
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int no_repeat_mask;

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int pitch_lag;

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float pitch_fac;

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} AMRFixed; 
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/**

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* TrackPulse Positions

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* 

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* 1  0  0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75

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* 

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* 2  1  1, 6, 11, 16, 21, 26, 31, 36, 41, 46, 51, 56, 61, 66, 71, 76

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* 

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* 3  2  2, 7, 12, 17, 22, 27, 32, 37, 42, 47, 52, 57, 62, 67, 72, 77

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* 

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*

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* Table contains only first the pulse indexes.

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*

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* Used in G.729 @@8k, G.729 @@4.4k, AMR @@7.95k, AMR @@7.40k

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*/

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extern const uint8_t ff_fc_4pulses_8bits_tracks_13[16]; 
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/**

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* TrackPulse Positions

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* 

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* 4  3  3, 8, 13, 18, 23, 28, 33, 38, 43, 48, 53, 58, 63, 68, 73, 78

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*   4, 9, 14, 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, 69, 74, 79

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* 

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*

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* @remark Track in the table should be read toptobottom, lefttoright.

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*

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* Used in G.729 @@8k, G.729 @@4.4k, AMR @@7.95k, AMR @@7.40k

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*/

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extern const uint8_t ff_fc_4pulses_8bits_track_4[32]; 
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/**

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* TrackPulse Positions

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* 

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* 1  0  1, 6, 11, 16, 21, 26, 31, 36

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*   3, 8, 13, 18, 23, 28, 33, 38

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* 

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*

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* @remark Track in the table should be read toptobottom, lefttoright.

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*

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* @note (EE) Reference G.729D code also uses gray decoding for each

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* pulse index before looking up the value in the table.

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*

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* Used in G.729 @@6.4k (with gray coding), AMR @@5.9k (without gray coding)

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*/

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extern const uint8_t ff_fc_2pulses_9bits_track1[16]; 
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extern const uint8_t ff_fc_2pulses_9bits_track1_gray[16]; 
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/**

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* TrackPulse Positions

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* 

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* 2  1  0, 7, 14, 20, 27, 34, 1, 21

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*   2, 9, 15, 22, 29, 35, 6, 26

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*   4,10, 17, 24, 30, 37, 11, 31

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*   5,12, 19, 25, 32, 39, 16, 36

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* 

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*

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* @remark Track in the table should be read toptobottom, lefttoright.

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*

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* @note (EE.1) This table (from the reference code) does not comply with

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* the specification.

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* The specification contains the following table:

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*

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* TrackPulse Positions

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* 

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* 2  1  0, 5, 10, 15, 20, 25, 30, 35

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*   1, 6, 11, 16, 21, 26, 31, 36

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*   2, 7, 12, 17, 22, 27, 32, 37

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*   4, 9, 14, 19, 24, 29, 34, 39

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*

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* 

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*

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* @note (EE.2) Reference G.729D code also uses gray decoding for each

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* pulse index before looking up the value in the table.

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*

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* Used in G.729 @@6.4k (with gray coding)

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*/

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extern const uint8_t ff_fc_2pulses_9bits_track2_gray[32]; 
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/**

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* b60 hamming windowed sinc function coefficients

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*/

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extern const float ff_b60_sinc[61]; 
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/**

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* Table of pow(0.7,n)

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*/

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extern const float ff_pow_0_7[10]; 
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/**

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* Table of pow(0.75,n)

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*/

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extern const float ff_pow_0_75[10]; 
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/**

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* Table of pow(0.55,n)

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*/

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extern const float ff_pow_0_55[10]; 
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/**

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* Decode fixedcodebook vector (3.8 and D.5.8 of G.729, 5.7.1 of AMR).

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* @param[out] fc_v decoded fixed codebook vector (2.13)

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* @param tab1 table used for first pulse_count pulses

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* @param tab2 table used for last pulse

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* @param pulse_indexes fixed codebook indexes

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* @param pulse_signs signs of the excitation pulses (0 bit value

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* means negative sign)

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* @param bits number of bits per one pulse index

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* @param pulse_count number of pulses decoded using first table

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* @param bits length of one pulse index in bits

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*

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* Used in G.729 @@8k, G.729 @@4.4k, G.729 @@6.4k, AMR @@7.95k, AMR @@7.40k

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*/

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void ff_acelp_fc_pulse_per_track(int16_t* fc_v,

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const uint8_t *tab1,

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const uint8_t *tab2,

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int pulse_indexes,

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int pulse_signs,

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int pulse_count,

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int bits);

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/**

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* Decode the algebraic codebook index to pulse positions and signs and

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* construct the algebraic codebook vector for MODE_12k2.

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*

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* @note: The positions and signs are explicitly coded in MODE_12k2.

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*

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* @param fixed_index positions of the ten pulses

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* @param fixed_sparse pointer to the algebraic codebook vector

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* @param gray_decode gray decoding table

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* @param half_pulse_count number of couples of pulses

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* @param bits length of one pulse index in bits

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*/

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void ff_decode_10_pulses_35bits(const int16_t *fixed_index, 
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AMRFixed *fixed_sparse, 
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const uint8_t *gray_decode,

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int half_pulse_count, int bits); 
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/**

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* weighted sum of two vectors with rounding.

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* @param[out] out result of addition

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* @param in_a first vector

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* @param in_b second vector

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* @param weight_coeff_a first vector weight coefficient

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* @param weight_coeff_a second vector weight coefficient

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* @param rounder this value will be added to the sum of the two vectors

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* @param shift result will be shifted to right by this value

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* @param length vectors length

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*

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* @note It is safe to pass the same buffer for out and in_a or in_b.

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*

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* out[i] = (in_a[i]*weight_a + in_b[i]*weight_b + rounder) >> shift

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*/

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void ff_acelp_weighted_vector_sum(int16_t* out,

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const int16_t *in_a,

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const int16_t *in_b,

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int16_t weight_coeff_a, 
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int16_t weight_coeff_b, 
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int16_t rounder, 
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int shift,

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int length);

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/**

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* float implementation of weighted sum of two vectors.

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* @param[out] out result of addition

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* @param in_a first vector

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* @param in_b second vector

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* @param weight_coeff_a first vector weight coefficient

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* @param weight_coeff_a second vector weight coefficient

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* @param length vectors length

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*

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* @note It is safe to pass the same buffer for out and in_a or in_b.

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*/

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void ff_weighted_vector_sumf(float *out, const float *in_a, const float *in_b, 
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float weight_coeff_a, float weight_coeff_b, 
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int length);

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/**

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* Adaptive gain control (as used in AMR postfiltering)

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*

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* @param out output buffer for filtered speech data

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* @param in the input speech buffer (may be the same as out)

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* @param speech_energ input energy

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* @param size the input buffer size

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* @param alpha exponential filter factor

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* @param gain_mem a pointer to the filter memory (single float of size)

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*/

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void ff_adaptive_gain_control(float *out, const float *in, float speech_energ, 
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int size, float alpha, float *gain_mem); 
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/**

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* Set the sum of squares of a signal by scaling

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*

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* @param out output samples

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* @param in input samples

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* @param sum_of_squares new sum of squares

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* @param n number of samples

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*

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* @note If the input is zero (or its energy underflows), the output is zero.

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* This is the behavior of AGC in the AMR reference decoder. The QCELP

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* reference decoder seems to have undefined behavior.

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*

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* TIA/EIA/IS733 2.4.8.32/3/4/5, 2.4.8.6

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* 3GPP TS 26.090 6.1 (6)

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*/

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void ff_scale_vector_to_given_sum_of_squares(float *out, const float *in, 
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float sum_of_squares, const int n); 
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/**

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* Add fixed vector to an array from a sparse representation

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*

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* @param out fixed vector with pitch sharpening

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* @param in sparse fixed vector

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* @param scale number to multiply the fixed vector by

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* @param size the output vector size

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*/

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void ff_set_fixed_vector(float *out, const AMRFixed *in, float scale, int size); 
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/**

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* Clear array values set by set_fixed_vector

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*

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* @param out fixed vector to be cleared

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* @param in sparse fixed vector

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* @param size the output vector size

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*/

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void ff_clear_fixed_vector(float *out, const AMRFixed *in, int size); 
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#endif /* AVCODEC_ACELP_VECTORS_H */ 