1/*
2 * Delphine Software International CIN audio decoder
3 * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
4 *
5 * This file is part of FFmpeg.
6 *
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20 */
21
22/**
23 * @file
24 * Delphine Software International CIN audio decoder
25 */
26
27#include "libavutil/channel_layout.h"
28
29#include "avcodec.h"
30#include "bytestream.h"
31#include "codec_internal.h"
32#include "internal.h"
33#include "mathops.h"
34
35typedef struct CinAudioContext {
36    int initial_decode_frame;
37    int delta;
38} CinAudioContext;
39
40
41/* table defining a geometric sequence with multiplier = 32767 ^ (1 / 128) */
42static const int16_t cinaudio_delta16_table[256] = {
43         0,      0,      0,      0,      0,      0,      0,      0,
44         0,      0,      0,      0,      0,      0,      0,      0,
45         0,      0,      0, -30210, -27853, -25680, -23677, -21829,
46    -20126, -18556, -17108, -15774, -14543, -13408, -12362, -11398,
47    -10508,  -9689,  -8933,  -8236,  -7593,  -7001,  -6455,  -5951,
48     -5487,  -5059,  -4664,  -4300,  -3964,  -3655,  -3370,  -3107,
49     -2865,  -2641,  -2435,  -2245,  -2070,  -1908,  -1759,  -1622,
50     -1495,  -1379,  -1271,  -1172,  -1080,   -996,   -918,   -847,
51      -781,   -720,   -663,   -612,   -564,   -520,   -479,   -442,
52      -407,   -376,   -346,   -319,   -294,   -271,   -250,   -230,
53      -212,   -196,   -181,   -166,   -153,   -141,   -130,   -120,
54      -111,   -102,    -94,    -87,    -80,    -74,    -68,    -62,
55       -58,    -53,    -49,    -45,    -41,    -38,    -35,    -32,
56       -30,    -27,    -25,    -23,    -21,    -20,    -18,    -17,
57       -15,    -14,    -13,    -12,    -11,    -10,     -9,     -8,
58        -7,     -6,     -5,     -4,     -3,     -2,     -1,      0,
59         0,      1,      2,      3,      4,      5,      6,      7,
60         8,      9,     10,     11,     12,     13,     14,     15,
61        17,     18,     20,     21,     23,     25,     27,     30,
62        32,     35,     38,     41,     45,     49,     53,     58,
63        62,     68,     74,     80,     87,     94,    102,    111,
64       120,    130,    141,    153,    166,    181,    196,    212,
65       230,    250,    271,    294,    319,    346,    376,    407,
66       442,    479,    520,    564,    612,    663,    720,    781,
67       847,    918,    996,   1080,   1172,   1271,   1379,   1495,
68      1622,   1759,   1908,   2070,   2245,   2435,   2641,   2865,
69      3107,   3370,   3655,   3964,   4300,   4664,   5059,   5487,
70      5951,   6455,   7001,   7593,   8236,   8933,   9689,  10508,
71     11398,  12362,  13408,  14543,  15774,  17108,  18556,  20126,
72     21829,  23677,  25680,  27853,  30210,      0,      0,      0,
73         0,      0,      0,      0,      0,      0,      0,      0,
74         0,      0,      0,      0,      0,      0,      0,      0
75};
76
77static av_cold int cinaudio_decode_init(AVCodecContext *avctx)
78{
79    CinAudioContext *cin = avctx->priv_data;
80
81    cin->initial_decode_frame = 1;
82    cin->delta                = 0;
83    avctx->sample_fmt         = AV_SAMPLE_FMT_S16;
84    av_channel_layout_uninit(&avctx->ch_layout);
85    avctx->ch_layout          = (AVChannelLayout)AV_CHANNEL_LAYOUT_MONO;
86
87    return 0;
88}
89
90static int cinaudio_decode_frame(AVCodecContext *avctx, AVFrame *frame,
91                                 int *got_frame_ptr, AVPacket *avpkt)
92{
93    const uint8_t *buf     = avpkt->data;
94    CinAudioContext *cin   = avctx->priv_data;
95    const uint8_t *buf_end = buf + avpkt->size;
96    int16_t *samples;
97    int delta, ret;
98
99    /* get output buffer */
100    frame->nb_samples = avpkt->size - cin->initial_decode_frame;
101    if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
102        return ret;
103    samples = (int16_t *)frame->data[0];
104
105    delta = cin->delta;
106    if (cin->initial_decode_frame) {
107        cin->initial_decode_frame = 0;
108        delta                     = sign_extend(AV_RL16(buf), 16);
109        buf                      += 2;
110        *samples++                = delta;
111    }
112    while (buf < buf_end) {
113        delta     += cinaudio_delta16_table[*buf++];
114        delta      = av_clip_int16(delta);
115        *samples++ = delta;
116    }
117    cin->delta = delta;
118
119    *got_frame_ptr = 1;
120
121    return avpkt->size;
122}
123
124const FFCodec ff_dsicinaudio_decoder = {
125    .p.name         = "dsicinaudio",
126    .p.long_name    = NULL_IF_CONFIG_SMALL("Delphine Software International CIN audio"),
127    .p.type         = AVMEDIA_TYPE_AUDIO,
128    .p.id           = AV_CODEC_ID_DSICINAUDIO,
129    .priv_data_size = sizeof(CinAudioContext),
130    .init           = cinaudio_decode_init,
131    FF_CODEC_DECODE_CB(cinaudio_decode_frame),
132    .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
133    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE,
134};
135