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
35 typedef 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) */
42 static 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
cinaudio_decode_init(AVCodecContext * avctx)77 static 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
cinaudio_decode_frame(AVCodecContext * avctx,AVFrame * frame,int * got_frame_ptr,AVPacket * avpkt)90 static 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
124 const 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