FFmpeg
dsicinaudio.c
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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 
28 #include "libavutil/intreadwrite.h"
29 
30 #include "avcodec.h"
31 #include "codec_internal.h"
32 #include "decode.h"
33 #include "mathops.h"
34 
35 typedef struct CinAudioContext {
37  int delta;
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 
78 {
79  CinAudioContext *cin = avctx->priv_data;
80 
81  cin->initial_decode_frame = 1;
82  cin->delta = 0;
86 
87  return 0;
88 }
89 
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++];
115  *samples++ = delta;
116  }
117  cin->delta = delta;
118 
119  *got_frame_ptr = 1;
120 
121  return avpkt->size;
122 }
123 
125  .p.name = "dsicinaudio",
126  CODEC_LONG_NAME("Delphine Software International CIN audio"),
127  .p.type = AVMEDIA_TYPE_AUDIO,
128  .p.id = AV_CODEC_ID_DSICINAUDIO,
129  .priv_data_size = sizeof(CinAudioContext),
132  .p.capabilities = AV_CODEC_CAP_DR1 | AV_CODEC_CAP_CHANNEL_CONF,
133 };
CinAudioContext::delta
int delta
Definition: dsicinaudio.c:37
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:389
AVPacket::data
uint8_t * data
Definition: packet.h:539
FFCodec
Definition: codec_internal.h:127
FFCodec::p
AVCodec p
The public AVCodec.
Definition: codec_internal.h:131
AVCodecContext::ch_layout
AVChannelLayout ch_layout
Audio channel layout.
Definition: avcodec.h:1071
CinAudioContext
Definition: dsicinaudio.c:35
av_cold
#define av_cold
Definition: attributes.h:90
FF_CODEC_DECODE_CB
#define FF_CODEC_DECODE_CB(func)
Definition: codec_internal.h:311
AV_CODEC_ID_DSICINAUDIO
@ AV_CODEC_ID_DSICINAUDIO
Definition: codec_id.h:472
intreadwrite.h
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
decode.h
AV_RL16
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:94
CODEC_LONG_NAME
#define CODEC_LONG_NAME(str)
Definition: codec_internal.h:296
if
if(ret)
Definition: filter_design.txt:179
av_clip_int16
#define av_clip_int16
Definition: common.h:115
mathops.h
AV_CODEC_CAP_CHANNEL_CONF
#define AV_CODEC_CAP_CHANNEL_CONF
Codec should fill in channel configuration and samplerate instead of container.
Definition: codec.h:106
ff_get_buffer
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1697
init
int(* init)(AVBSFContext *ctx)
Definition: dts2pts.c:368
AV_CODEC_CAP_DR1
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() or get_encode_buffer() for allocating buffers and supports custom allocators.
Definition: codec.h:52
AVPacket::size
int size
Definition: packet.h:540
AVChannelLayout
An AVChannelLayout holds information about the channel layout of audio data.
Definition: channel_layout.h:311
codec_internal.h
AVCodecContext::sample_fmt
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:1063
ff_dsicinaudio_decoder
const FFCodec ff_dsicinaudio_decoder
Definition: dsicinaudio.c:124
cinaudio_decode_init
static av_cold int cinaudio_decode_init(AVCodecContext *avctx)
Definition: dsicinaudio.c:77
delta
float delta
Definition: vorbis_enc_data.h:430
AV_SAMPLE_FMT_S16
@ AV_SAMPLE_FMT_S16
signed 16 bits
Definition: samplefmt.h:58
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:194
cinaudio_decode_frame
static int cinaudio_decode_frame(AVCodecContext *avctx, AVFrame *frame, int *got_frame_ptr, AVPacket *avpkt)
Definition: dsicinaudio.c:90
avcodec.h
ret
ret
Definition: filter_design.txt:187
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
AVCodecContext
main external API structure.
Definition: avcodec.h:451
channel_layout.h
av_channel_layout_uninit
void av_channel_layout_uninit(AVChannelLayout *channel_layout)
Free any allocated data in the channel layout and reset the channel count to 0.
Definition: channel_layout.c:437
sign_extend
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:131
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
cinaudio_delta16_table
static const int16_t cinaudio_delta16_table[256]
Definition: dsicinaudio.c:42
AV_CHANNEL_LAYOUT_MONO
#define AV_CHANNEL_LAYOUT_MONO
Definition: channel_layout.h:386
AVPacket
This structure stores compressed data.
Definition: packet.h:516
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:478
CinAudioContext::initial_decode_frame
int initial_decode_frame
Definition: dsicinaudio.c:36