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 "internal.h" 32#include "mathops.h" 33 34typedef struct CinAudioContext { 35 int initial_decode_frame; 36 int delta; 37} CinAudioContext; 38 39 40/* table defining a geometric sequence with multiplier = 32767 ^ (1 / 128) */ 41static const int16_t cinaudio_delta16_table[256] = { 42 0, 0, 0, 0, 0, 0, 0, 0, 43 0, 0, 0, 0, 0, 0, 0, 0, 44 0, 0, 0, -30210, -27853, -25680, -23677, -21829, 45 -20126, -18556, -17108, -15774, -14543, -13408, -12362, -11398, 46 -10508, -9689, -8933, -8236, -7593, -7001, -6455, -5951, 47 -5487, -5059, -4664, -4300, -3964, -3655, -3370, -3107, 48 -2865, -2641, -2435, -2245, -2070, -1908, -1759, -1622, 49 -1495, -1379, -1271, -1172, -1080, -996, -918, -847, 50 -781, -720, -663, -612, -564, -520, -479, -442, 51 -407, -376, -346, -319, -294, -271, -250, -230, 52 -212, -196, -181, -166, -153, -141, -130, -120, 53 -111, -102, -94, -87, -80, -74, -68, -62, 54 -58, -53, -49, -45, -41, -38, -35, -32, 55 -30, -27, -25, -23, -21, -20, -18, -17, 56 -15, -14, -13, -12, -11, -10, -9, -8, 57 -7, -6, -5, -4, -3, -2, -1, 0, 58 0, 1, 2, 3, 4, 5, 6, 7, 59 8, 9, 10, 11, 12, 13, 14, 15, 60 17, 18, 20, 21, 23, 25, 27, 30, 61 32, 35, 38, 41, 45, 49, 53, 58, 62 62, 68, 74, 80, 87, 94, 102, 111, 63 120, 130, 141, 153, 166, 181, 196, 212, 64 230, 250, 271, 294, 319, 346, 376, 407, 65 442, 479, 520, 564, 612, 663, 720, 781, 66 847, 918, 996, 1080, 1172, 1271, 1379, 1495, 67 1622, 1759, 1908, 2070, 2245, 2435, 2641, 2865, 68 3107, 3370, 3655, 3964, 4300, 4664, 5059, 5487, 69 5951, 6455, 7001, 7593, 8236, 8933, 9689, 10508, 70 11398, 12362, 13408, 14543, 15774, 17108, 18556, 20126, 71 21829, 23677, 25680, 27853, 30210, 0, 0, 0, 72 0, 0, 0, 0, 0, 0, 0, 0, 73 0, 0, 0, 0, 0, 0, 0, 0 74}; 75 76static av_cold int cinaudio_decode_init(AVCodecContext *avctx) 77{ 78 CinAudioContext *cin = avctx->priv_data; 79 80 cin->initial_decode_frame = 1; 81 cin->delta = 0; 82 avctx->sample_fmt = AV_SAMPLE_FMT_S16; 83 avctx->channels = 1; 84 avctx->channel_layout = AV_CH_LAYOUT_MONO; 85 86 return 0; 87} 88 89static int cinaudio_decode_frame(AVCodecContext *avctx, void *data, 90 int *got_frame_ptr, AVPacket *avpkt) 91{ 92 AVFrame *frame = data; 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 124AVCodec ff_dsicinaudio_decoder = { 125 .name = "dsicinaudio", 126 .long_name = NULL_IF_CONFIG_SMALL("Delphine Software International CIN audio"), 127 .type = AVMEDIA_TYPE_AUDIO, 128 .id = AV_CODEC_ID_DSICINAUDIO, 129 .priv_data_size = sizeof(CinAudioContext), 130 .init = cinaudio_decode_init, 131 .decode = cinaudio_decode_frame, 132 .capabilities = CODEC_CAP_DR1, 133}; 134