1 /*
2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10
11 /******************************************************************
12
13 iLBC Speech Coder ANSI-C Source Code
14
15 WebRtcIlbcfix_CbMemEnergy.c
16
17 ******************************************************************/
18
19 #include "modules/audio_coding/codecs/ilbc/cb_mem_energy.h"
20
21 #include "modules/audio_coding/codecs/ilbc/cb_mem_energy_calc.h"
22 #include "modules/audio_coding/codecs/ilbc/constants.h"
23 #include "modules/audio_coding/codecs/ilbc/defines.h"
24
25 /*----------------------------------------------------------------*
26 * Function WebRtcIlbcfix_CbMemEnergy computes the energy of all
27 * the vectors in the codebook memory that will be used in the
28 * following search for the best match.
29 *----------------------------------------------------------------*/
30
WebRtcIlbcfix_CbMemEnergy(size_t range,int16_t * CB,int16_t * filteredCB,size_t lMem,size_t lTarget,int16_t * energyW16,int16_t * energyShifts,int scale,size_t base_size)31 void WebRtcIlbcfix_CbMemEnergy(
32 size_t range,
33 int16_t *CB, /* (i) The CB memory (1:st section) */
34 int16_t *filteredCB, /* (i) The filtered CB memory (2:nd section) */
35 size_t lMem, /* (i) Length of the CB memory */
36 size_t lTarget, /* (i) Length of the target vector */
37 int16_t *energyW16, /* (o) Energy in the CB vectors */
38 int16_t *energyShifts, /* (o) Shift value of the energy */
39 int scale, /* (i) The scaling of all energy values */
40 size_t base_size /* (i) Index to where energy values should be stored */
41 ) {
42 int16_t *ppi, *ppo, *pp;
43 int32_t energy, tmp32;
44
45 /* Compute the energy and store it in a vector. Also the
46 * corresponding shift values are stored. The energy values
47 * are reused in all three stages. */
48
49 /* Calculate the energy in the first block of 'lTarget' sampels. */
50 ppi = CB+lMem-lTarget-1;
51 ppo = CB+lMem-1;
52
53 pp=CB+lMem-lTarget;
54 energy = WebRtcSpl_DotProductWithScale( pp, pp, lTarget, scale);
55
56 /* Normalize the energy and store the number of shifts */
57 energyShifts[0] = (int16_t)WebRtcSpl_NormW32(energy);
58 tmp32 = energy << energyShifts[0];
59 energyW16[0] = (int16_t)(tmp32 >> 16);
60
61 /* Compute the energy of the rest of the cb memory
62 * by step wise adding and subtracting the next
63 * sample and the last sample respectively. */
64 WebRtcIlbcfix_CbMemEnergyCalc(energy, range, ppi, ppo, energyW16, energyShifts, scale, 0);
65
66 /* Next, precompute the energy values for the filtered cb section */
67 energy=0;
68 pp=filteredCB+lMem-lTarget;
69
70 energy = WebRtcSpl_DotProductWithScale( pp, pp, lTarget, scale);
71
72 /* Normalize the energy and store the number of shifts */
73 energyShifts[base_size] = (int16_t)WebRtcSpl_NormW32(energy);
74 tmp32 = energy << energyShifts[base_size];
75 energyW16[base_size] = (int16_t)(tmp32 >> 16);
76
77 ppi = filteredCB + lMem - 1 - lTarget;
78 ppo = filteredCB + lMem - 1;
79
80 WebRtcIlbcfix_CbMemEnergyCalc(energy, range, ppi, ppo, energyW16, energyShifts, scale, base_size);
81 }
82