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 
29 #include "avcodec.h"
30 #include "bytestream.h"
31 #include "internal.h"
32 #include "mathops.h"
33 
34 typedef struct CinAudioContext {
36  int delta;
38 
39 
40 /* table defining a geometric sequence with multiplier = 32767 ^ (1 / 128) */
41 static 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 
77 {
78  CinAudioContext *cin = avctx->priv_data;
79 
80  cin->initial_decode_frame = 1;
81  cin->delta = 0;
83  avctx->channels = 1;
85 
86  return 0;
87 }
88 
89 static 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 
125  .name = "dsicinaudio",
126  .long_name = NULL_IF_CONFIG_SMALL("Delphine Software International CIN audio"),
127  .type = AVMEDIA_TYPE_AUDIO,
129  .priv_data_size = sizeof(CinAudioContext),
132  .capabilities = AV_CODEC_CAP_DR1,
133 };
This structure describes decoded (raw) audio or video data.
Definition: frame.h:268
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
int size
Definition: avcodec.h:1478
AVCodec.
Definition: avcodec.h:3477
uint64_t_TMPL AV_WL64 unsigned int_TMPL AV_WL32 unsigned int_TMPL AV_WL24 unsigned int_TMPL AV_RL16
Definition: bytestream.h:87
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:42
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2229
uint8_t
#define av_cold
Definition: attributes.h:82
static av_cold int cinaudio_decode_init(AVCodecContext *avctx)
Definition: dsicinaudio.c:76
uint8_t * data
Definition: avcodec.h:1477
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
const char * name
Name of the codec implementation.
Definition: avcodec.h:3484
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:2272
static const int16_t cinaudio_delta16_table[256]
Definition: dsicinaudio.c:41
audio channel layout utility functions
static int cinaudio_decode_frame(AVCodecContext *avctx, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: dsicinaudio.c:89
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
if(ret)
Libavcodec external API header.
main external API structure.
Definition: avcodec.h:1565
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1964
void * buf
Definition: avisynth_c.h:766
static av_const int sign_extend(int val, unsigned bits)
Definition: mathops.h:130
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:282
common internal api header.
signed 16 bits
Definition: samplefmt.h:61
void * priv_data
Definition: avcodec.h:1592
int channels
number of audio channels
Definition: avcodec.h:2222
Filter the word “frame” indicates either a video frame or a group of audio samples
AVCodec ff_dsicinaudio_decoder
Definition: dsicinaudio.c:124
#define AV_CH_LAYOUT_MONO
int initial_decode_frame
Definition: dsicinaudio.c:35
This structure stores compressed data.
Definition: avcodec.h:1454
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:334
#define AV_CODEC_CAP_DR1
Codec uses get_buffer() for allocating buffers and supports custom allocators.
Definition: avcodec.h:981