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acelp_vectors.h
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1 /*
2  * adaptive and fixed codebook vector operations for ACELP-based codecs
3  *
4  * Copyright (c) 2008 Vladimir Voroshilov
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 #ifndef AVCODEC_ACELP_VECTORS_H
24 #define AVCODEC_ACELP_VECTORS_H
25 
26 #include <stdint.h>
27 
28 typedef struct ACELPVContext {
29  /**
30  * float implementation of weighted sum of two vectors.
31  * @param[out] out result of addition
32  * @param in_a first vector
33  * @param in_b second vector
34  * @param weight_coeff_a first vector weight coefficient
35  * @param weight_coeff_a second vector weight coefficient
36  * @param length vectors length (should be a multiple of two)
37  *
38  * @note It is safe to pass the same buffer for out and in_a or in_b.
39  */
40  void (*weighted_vector_sumf)(float *out, const float *in_a, const float *in_b,
41  float weight_coeff_a, float weight_coeff_b,
42  int length);
43 
44 }ACELPVContext;
45 
46 /**
47  * Initialize ACELPVContext.
48  */
49 void ff_acelp_vectors_init(ACELPVContext *c);
50 void ff_acelp_vectors_init_mips(ACELPVContext *c);
51 
52 /** Sparse representation for the algebraic codebook (fixed) vector */
53 typedef struct AMRFixed {
54  int n;
55  int x[10];
56  float y[10];
57  int no_repeat_mask;
58  int pitch_lag;
59  float pitch_fac;
60 } AMRFixed;
61 
62 /**
63  * Track|Pulse| Positions
64  * -------------------------------------------------------------------------
65  * 1 | 0 | 0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75
66  * -------------------------------------------------------------------------
67  * 2 | 1 | 1, 6, 11, 16, 21, 26, 31, 36, 41, 46, 51, 56, 61, 66, 71, 76
68  * -------------------------------------------------------------------------
69  * 3 | 2 | 2, 7, 12, 17, 22, 27, 32, 37, 42, 47, 52, 57, 62, 67, 72, 77
70  * -------------------------------------------------------------------------
71  *
72  * Table contains only first the pulse indexes.
73  *
74  * Used in G.729 @@8k, G.729 @@4.4k, AMR @@7.95k, AMR @@7.40k
75  */
76 extern const uint8_t ff_fc_4pulses_8bits_tracks_13[16];
77 
78 /**
79  * Track|Pulse| Positions
80  * -------------------------------------------------------------------------
81  * 4 | 3 | 3, 8, 13, 18, 23, 28, 33, 38, 43, 48, 53, 58, 63, 68, 73, 78
82  * | | 4, 9, 14, 19, 24, 29, 34, 39, 44, 49, 54, 59, 64, 69, 74, 79
83  * -------------------------------------------------------------------------
84  *
85  * @remark Track in the table should be read top-to-bottom, left-to-right.
86  *
87  * Used in G.729 @@8k, G.729 @@4.4k, AMR @@7.95k, AMR @@7.40k
88  */
89 extern const uint8_t ff_fc_4pulses_8bits_track_4[32];
90 
91 /**
92  * Track|Pulse| Positions
93  * -----------------------------------------
94  * 1 | 0 | 1, 6, 11, 16, 21, 26, 31, 36
95  * | | 3, 8, 13, 18, 23, 28, 33, 38
96  * -----------------------------------------
97  *
98  * @remark Track in the table should be read top-to-bottom, left-to-right.
99  *
100  * @note (EE) Reference G.729D code also uses gray decoding for each
101  * pulse index before looking up the value in the table.
102  *
103  * Used in G.729 @@6.4k (with gray coding), AMR @@5.9k (without gray coding)
104  */
105 extern const uint8_t ff_fc_2pulses_9bits_track1[16];
106 extern const uint8_t ff_fc_2pulses_9bits_track1_gray[16];
107 
108 /**
109  * Track|Pulse| Positions
110  * -----------------------------------------
111  * 2 | 1 | 0, 7, 14, 20, 27, 34, 1, 21
112  * | | 2, 9, 15, 22, 29, 35, 6, 26
113  * | | 4,10, 17, 24, 30, 37, 11, 31
114  * | | 5,12, 19, 25, 32, 39, 16, 36
115  * -----------------------------------------
116  *
117  * @remark Track in the table should be read top-to-bottom, left-to-right.
118  *
119  * @note (EE.1) This table (from the reference code) does not comply with
120  * the specification.
121  * The specification contains the following table:
122  *
123  * Track|Pulse| Positions
124  * -----------------------------------------
125  * 2 | 1 | 0, 5, 10, 15, 20, 25, 30, 35
126  * | | 1, 6, 11, 16, 21, 26, 31, 36
127  * | | 2, 7, 12, 17, 22, 27, 32, 37
128  * | | 4, 9, 14, 19, 24, 29, 34, 39
129  *
130  * -----------------------------------------
131  *
132  * @note (EE.2) Reference G.729D code also uses gray decoding for each
133  * pulse index before looking up the value in the table.
134  *
135  * Used in G.729 @@6.4k (with gray coding)
136  */
137 extern const uint8_t ff_fc_2pulses_9bits_track2_gray[32];
138 
139 /**
140  * b60 hamming windowed sinc function coefficients
141  */
142 extern const float ff_b60_sinc[61];
143 
144 /**
145  * Table of pow(0.7,n)
146  */
147 extern const float ff_pow_0_7[10];
148 
149 /**
150  * Table of pow(0.75,n)
151  */
152 extern const float ff_pow_0_75[10];
153 
154 /**
155  * Table of pow(0.55,n)
156  */
157 extern const float ff_pow_0_55[10];
158 
159 /**
160  * Decode fixed-codebook vector (3.8 and D.5.8 of G.729, 5.7.1 of AMR).
161  * @param[out] fc_v decoded fixed codebook vector (2.13)
162  * @param tab1 table used for first pulse_count pulses
163  * @param tab2 table used for last pulse
164  * @param pulse_indexes fixed codebook indexes
165  * @param pulse_signs signs of the excitation pulses (0 bit value
166  * means negative sign)
167  * @param bits number of bits per one pulse index
168  * @param pulse_count number of pulses decoded using first table
169  * @param bits length of one pulse index in bits
170  *
171  * Used in G.729 @@8k, G.729 @@4.4k, G.729 @@6.4k, AMR @@7.95k, AMR @@7.40k
172  */
173 void ff_acelp_fc_pulse_per_track(int16_t* fc_v,
174  const uint8_t *tab1,
175  const uint8_t *tab2,
176  int pulse_indexes,
177  int pulse_signs,
178  int pulse_count,
179  int bits);
180 
181 /**
182  * Decode the algebraic codebook index to pulse positions and signs and
183  * construct the algebraic codebook vector for MODE_12k2.
184  *
185  * @note: The positions and signs are explicitly coded in MODE_12k2.
186  *
187  * @param fixed_index positions of the ten pulses
188  * @param fixed_sparse pointer to the algebraic codebook vector
189  * @param gray_decode gray decoding table
190  * @param half_pulse_count number of couples of pulses
191  * @param bits length of one pulse index in bits
192  */
193 void ff_decode_10_pulses_35bits(const int16_t *fixed_index,
194  AMRFixed *fixed_sparse,
195  const uint8_t *gray_decode,
196  int half_pulse_count, int bits);
197 
198 
199 /**
200  * weighted sum of two vectors with rounding.
201  * @param[out] out result of addition
202  * @param in_a first vector
203  * @param in_b second vector
204  * @param weight_coeff_a first vector weight coefficient
205  * @param weight_coeff_a second vector weight coefficient
206  * @param rounder this value will be added to the sum of the two vectors
207  * @param shift result will be shifted to right by this value
208  * @param length vectors length
209  *
210  * @note It is safe to pass the same buffer for out and in_a or in_b.
211  *
212  * out[i] = (in_a[i]*weight_a + in_b[i]*weight_b + rounder) >> shift
213  */
214 void ff_acelp_weighted_vector_sum(int16_t* out,
215  const int16_t *in_a,
216  const int16_t *in_b,
217  int16_t weight_coeff_a,
218  int16_t weight_coeff_b,
219  int16_t rounder,
220  int shift,
221  int length);
222 
223 /**
224  * float implementation of weighted sum of two vectors.
225  * @param[out] out result of addition
226  * @param in_a first vector
227  * @param in_b second vector
228  * @param weight_coeff_a first vector weight coefficient
229  * @param weight_coeff_a second vector weight coefficient
230  * @param length vectors length
231  *
232  * @note It is safe to pass the same buffer for out and in_a or in_b.
233  */
234 void ff_weighted_vector_sumf(float *out, const float *in_a, const float *in_b,
235  float weight_coeff_a, float weight_coeff_b,
236  int length);
237 
238 /**
239  * Adaptive gain control (as used in AMR postfiltering)
240  *
241  * @param out output buffer for filtered speech data
242  * @param in the input speech buffer (may be the same as out)
243  * @param speech_energ input energy
244  * @param size the input buffer size
245  * @param alpha exponential filter factor
246  * @param gain_mem a pointer to the filter memory (single float of size)
247  */
248 void ff_adaptive_gain_control(float *out, const float *in, float speech_energ,
249  int size, float alpha, float *gain_mem);
250 
251 /**
252  * Set the sum of squares of a signal by scaling
253  *
254  * @param out output samples
255  * @param in input samples
256  * @param sum_of_squares new sum of squares
257  * @param n number of samples
258  *
259  * @note If the input is zero (or its energy underflows), the output is zero.
260  * This is the behavior of AGC in the AMR reference decoder. The QCELP
261  * reference decoder seems to have undefined behavior.
262  *
263  * TIA/EIA/IS-733 2.4.8.3-2/3/4/5, 2.4.8.6
264  * 3GPP TS 26.090 6.1 (6)
265  */
266 void ff_scale_vector_to_given_sum_of_squares(float *out, const float *in,
267  float sum_of_squares, const int n);
268 
269 /**
270  * Add fixed vector to an array from a sparse representation
271  *
272  * @param out fixed vector with pitch sharpening
273  * @param in sparse fixed vector
274  * @param scale number to multiply the fixed vector by
275  * @param size the output vector size
276  */
277 void ff_set_fixed_vector(float *out, const AMRFixed *in, float scale, int size);
278 
279 /**
280  * Clear array values set by set_fixed_vector
281  *
282  * @param out fixed vector to be cleared
283  * @param in sparse fixed vector
284  * @param size the output vector size
285  */
286 void ff_clear_fixed_vector(float *out, const AMRFixed *in, int size);
287 
288 #endif /* AVCODEC_ACELP_VECTORS_H */
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