xref: /aosp_15_r20/external/webrtc/modules/audio_coding/codecs/ilbc/init_decode.c (revision d9f758449e529ab9291ac668be2861e7a55c2422)
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_InitDecode.c
16 
17 ******************************************************************/
18 
19 #include "modules/audio_coding/codecs/ilbc/init_decode.h"
20 
21 #include "modules/audio_coding/codecs/ilbc/constants.h"
22 #include "modules/audio_coding/codecs/ilbc/defines.h"
23 
24 /*----------------------------------------------------------------*
25  *  Initiation of decoder instance.
26  *---------------------------------------------------------------*/
27 
WebRtcIlbcfix_InitDecode(IlbcDecoder * iLBCdec_inst,int16_t mode,int use_enhancer)28 int WebRtcIlbcfix_InitDecode(  /* (o) Number of decoded samples */
29     IlbcDecoder *iLBCdec_inst,  /* (i/o) Decoder instance */
30     int16_t mode,  /* (i) frame size mode */
31     int use_enhancer) {  /* (i) 1: use enhancer, 0: no enhancer */
32   int i;
33 
34   iLBCdec_inst->mode = mode;
35 
36   /* Set all the variables that are dependent on the frame size mode */
37   if (mode==30) {
38     iLBCdec_inst->blockl = BLOCKL_30MS;
39     iLBCdec_inst->nsub = NSUB_30MS;
40     iLBCdec_inst->nasub = NASUB_30MS;
41     iLBCdec_inst->lpc_n = LPC_N_30MS;
42     iLBCdec_inst->no_of_bytes = NO_OF_BYTES_30MS;
43     iLBCdec_inst->no_of_words = NO_OF_WORDS_30MS;
44     iLBCdec_inst->state_short_len=STATE_SHORT_LEN_30MS;
45   }
46   else if (mode==20) {
47     iLBCdec_inst->blockl = BLOCKL_20MS;
48     iLBCdec_inst->nsub = NSUB_20MS;
49     iLBCdec_inst->nasub = NASUB_20MS;
50     iLBCdec_inst->lpc_n = LPC_N_20MS;
51     iLBCdec_inst->no_of_bytes = NO_OF_BYTES_20MS;
52     iLBCdec_inst->no_of_words = NO_OF_WORDS_20MS;
53     iLBCdec_inst->state_short_len=STATE_SHORT_LEN_20MS;
54   }
55   else {
56     return(-1);
57   }
58 
59   /* Reset all the previous LSF to mean LSF */
60   WEBRTC_SPL_MEMCPY_W16(iLBCdec_inst->lsfdeqold, WebRtcIlbcfix_kLsfMean, LPC_FILTERORDER);
61 
62   /* Clear the synthesis filter memory */
63   WebRtcSpl_MemSetW16(iLBCdec_inst->syntMem, 0, LPC_FILTERORDER);
64 
65   /* Set the old synthesis filter to {1.0 0.0 ... 0.0} */
66   WebRtcSpl_MemSetW16(iLBCdec_inst->old_syntdenum, 0, ((LPC_FILTERORDER + 1)*NSUB_MAX));
67   for (i=0; i<NSUB_MAX; i++) {
68     iLBCdec_inst->old_syntdenum[i*(LPC_FILTERORDER+1)] = 4096;
69   }
70 
71   /* Clear the variables that are used for the PLC */
72   iLBCdec_inst->last_lag = 20;
73   iLBCdec_inst->consPLICount = 0;
74   iLBCdec_inst->prevPLI = 0;
75   iLBCdec_inst->perSquare = 0;
76   iLBCdec_inst->prevLag = 120;
77   iLBCdec_inst->prevLpc[0] = 4096;
78   WebRtcSpl_MemSetW16(iLBCdec_inst->prevLpc+1, 0, LPC_FILTERORDER);
79   WebRtcSpl_MemSetW16(iLBCdec_inst->prevResidual, 0, BLOCKL_MAX);
80 
81   /* Initialize the seed for the random number generator */
82   iLBCdec_inst->seed = 777;
83 
84   /* Set the filter state of the HP filter to 0 */
85   WebRtcSpl_MemSetW16(iLBCdec_inst->hpimemx, 0, 2);
86   WebRtcSpl_MemSetW16(iLBCdec_inst->hpimemy, 0, 4);
87 
88   /* Set the variables that are used in the ehnahcer */
89   iLBCdec_inst->use_enhancer = use_enhancer;
90   WebRtcSpl_MemSetW16(iLBCdec_inst->enh_buf, 0, (ENH_BUFL+ENH_BUFL_FILTEROVERHEAD));
91   for (i=0;i<ENH_NBLOCKS_TOT;i++) {
92     iLBCdec_inst->enh_period[i]=160; /* Q(-4) */
93   }
94 
95   iLBCdec_inst->prev_enh_pl = 0;
96 
97   return (int)(iLBCdec_inst->blockl);
98 }
99