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g722.h
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1 /*
2  * Copyright (c) CMU 1993 Computer Science, Speech Group
3  * Chengxiang Lu and Alex Hauptmann
4  * Copyright (c) 2005 Steve Underwood <steveu at coppice.org>
5  * Copyright (c) 2009 Kenan Gillet
6  * Copyright (c) 2010 Martin Storsjo
7  *
8  * This file is part of FFmpeg.
9  *
10  * FFmpeg is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU Lesser General Public
12  * License as published by the Free Software Foundation; either
13  * version 2.1 of the License, or (at your option) any later version.
14  *
15  * FFmpeg is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18  * Lesser General Public License for more details.
19  *
20  * You should have received a copy of the GNU Lesser General Public
21  * License along with FFmpeg; if not, write to the Free Software
22  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23  */
24 
25 #ifndef AVCODEC_G722_H
26 #define AVCODEC_G722_H
27 
28 #include <stdint.h>
29 #include "avcodec.h"
30 
31 #define PREV_SAMPLES_BUF_SIZE 1024
32 
33 typedef struct G722Context {
34  const AVClass *class;
36  int16_t prev_samples[PREV_SAMPLES_BUF_SIZE]; ///< memory of past decoded samples
37  int prev_samples_pos; ///< the number of values in prev_samples
38 
39  /**
40  * The band[0] and band[1] correspond respectively to the lower band and higher band.
41  */
42  struct G722Band {
43  int16_t s_predictor; ///< predictor output value
44  int32_t s_zero; ///< previous output signal from zero predictor
45  int8_t part_reconst_mem[2]; ///< signs of previous partially reconstructed signals
46  int16_t prev_qtzd_reconst; ///< previous quantized reconstructed signal (internal value, using low_inv_quant4)
47  int16_t pole_mem[2]; ///< second-order pole section coefficient buffer
48  int32_t diff_mem[6]; ///< quantizer difference signal memory
49  int16_t zero_mem[6]; ///< Seventh-order zero section coefficient buffer
50  int16_t log_factor; ///< delayed 2-logarithmic quantizer factor
51  int16_t scale_factor; ///< delayed quantizer scale factor
52  } band[2];
53 
54  struct TrellisNode {
55  struct G722Band state;
56  uint32_t ssd;
57  int path;
58  } *node_buf[2], **nodep_buf[2];
59 
60  struct TrellisPath {
61  int value;
62  int prev;
63  } *paths[2];
64 } G722Context;
65 
66 extern const int16_t ff_g722_high_inv_quant[4];
67 extern const int16_t ff_g722_low_inv_quant4[16];
68 extern const int16_t ff_g722_low_inv_quant6[64];
69 
70 void ff_g722_update_low_predictor(struct G722Band *band, const int ilow);
71 
72 void ff_g722_update_high_predictor(struct G722Band *band, const int dhigh,
73  const int ihigh);
74 
75 void ff_g722_apply_qmf(const int16_t *prev_samples, int *xout1, int *xout2);
76 
77 #endif /* AVCODEC_G722_H */