pineapple-src/externals/ffmpeg/libavcodec/dsicinaudio.c

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2021-02-09 03:25:58 +00:00
/*
* Delphine Software International CIN audio decoder
* Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Delphine Software International CIN audio decoder
*/
#include "libavutil/channel_layout.h"
#include "avcodec.h"
#include "bytestream.h"
#include "internal.h"
#include "mathops.h"
typedef struct CinAudioContext {
int initial_decode_frame;
int delta;
} CinAudioContext;
/* table defining a geometric sequence with multiplier = 32767 ^ (1 / 128) */
static const int16_t cinaudio_delta16_table[256] = {
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, -30210, -27853, -25680, -23677, -21829,
-20126, -18556, -17108, -15774, -14543, -13408, -12362, -11398,
-10508, -9689, -8933, -8236, -7593, -7001, -6455, -5951,
-5487, -5059, -4664, -4300, -3964, -3655, -3370, -3107,
-2865, -2641, -2435, -2245, -2070, -1908, -1759, -1622,
-1495, -1379, -1271, -1172, -1080, -996, -918, -847,
-781, -720, -663, -612, -564, -520, -479, -442,
-407, -376, -346, -319, -294, -271, -250, -230,
-212, -196, -181, -166, -153, -141, -130, -120,
-111, -102, -94, -87, -80, -74, -68, -62,
-58, -53, -49, -45, -41, -38, -35, -32,
-30, -27, -25, -23, -21, -20, -18, -17,
-15, -14, -13, -12, -11, -10, -9, -8,
-7, -6, -5, -4, -3, -2, -1, 0,
0, 1, 2, 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15,
17, 18, 20, 21, 23, 25, 27, 30,
32, 35, 38, 41, 45, 49, 53, 58,
62, 68, 74, 80, 87, 94, 102, 111,
120, 130, 141, 153, 166, 181, 196, 212,
230, 250, 271, 294, 319, 346, 376, 407,
442, 479, 520, 564, 612, 663, 720, 781,
847, 918, 996, 1080, 1172, 1271, 1379, 1495,
1622, 1759, 1908, 2070, 2245, 2435, 2641, 2865,
3107, 3370, 3655, 3964, 4300, 4664, 5059, 5487,
5951, 6455, 7001, 7593, 8236, 8933, 9689, 10508,
11398, 12362, 13408, 14543, 15774, 17108, 18556, 20126,
21829, 23677, 25680, 27853, 30210, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0
};
static av_cold int cinaudio_decode_init(AVCodecContext *avctx)
{
CinAudioContext *cin = avctx->priv_data;
cin->initial_decode_frame = 1;
cin->delta = 0;
avctx->sample_fmt = AV_SAMPLE_FMT_S16;
avctx->channels = 1;
avctx->channel_layout = AV_CH_LAYOUT_MONO;
return 0;
}
static int cinaudio_decode_frame(AVCodecContext *avctx, void *data,
int *got_frame_ptr, AVPacket *avpkt)
{
AVFrame *frame = data;
const uint8_t *buf = avpkt->data;
CinAudioContext *cin = avctx->priv_data;
const uint8_t *buf_end = buf + avpkt->size;
int16_t *samples;
int delta, ret;
/* get output buffer */
frame->nb_samples = avpkt->size - cin->initial_decode_frame;
if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
return ret;
samples = (int16_t *)frame->data[0];
delta = cin->delta;
if (cin->initial_decode_frame) {
cin->initial_decode_frame = 0;
delta = sign_extend(AV_RL16(buf), 16);
buf += 2;
*samples++ = delta;
}
while (buf < buf_end) {
delta += cinaudio_delta16_table[*buf++];
delta = av_clip_int16(delta);
*samples++ = delta;
}
cin->delta = delta;
*got_frame_ptr = 1;
return avpkt->size;
}
AVCodec ff_dsicinaudio_decoder = {
.name = "dsicinaudio",
.long_name = NULL_IF_CONFIG_SMALL("Delphine Software International CIN audio"),
.type = AVMEDIA_TYPE_AUDIO,
.id = AV_CODEC_ID_DSICINAUDIO,
.priv_data_size = sizeof(CinAudioContext),
.init = cinaudio_decode_init,
.decode = cinaudio_decode_frame,
.capabilities = AV_CODEC_CAP_DR1,
};