libopencore-amr.c
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1 /*
2  * AMR Audio decoder stub
3  * Copyright (c) 2003 the ffmpeg project
4  *
5  * This file is part of Libav.
6  *
7  * Libav 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  * Libav 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 Libav; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "avcodec.h"
23 #include "libavutil/avstring.h"
24 #include "libavutil/opt.h"
25 
27 {
28  const int is_amr_wb = 1 + (avctx->codec_id == CODEC_ID_AMR_WB);
29 
30  if (!avctx->sample_rate)
31  avctx->sample_rate = 8000 * is_amr_wb;
32 
33  if (!avctx->channels)
34  avctx->channels = 1;
35 
36  avctx->frame_size = 160 * is_amr_wb;
38 }
39 
40 #if CONFIG_LIBOPENCORE_AMRNB
41 
42 #include <opencore-amrnb/interf_dec.h>
43 #include <opencore-amrnb/interf_enc.h>
44 
45 /* Common code for fixed and float version*/
46 typedef struct AMR_bitrates {
47  int rate;
48  enum Mode mode;
49 } AMR_bitrates;
50 
51 /* Match desired bitrate */
52 static int get_bitrate_mode(int bitrate, void *log_ctx)
53 {
54  /* make the correspondance between bitrate and mode */
55  static const AMR_bitrates rates[] = {
56  { 4750, MR475 }, { 5150, MR515 }, { 5900, MR59 }, { 6700, MR67 },
57  { 7400, MR74 }, { 7950, MR795 }, { 10200, MR102 }, { 12200, MR122 }
58  };
59  int i, best = -1, min_diff = 0;
60  char log_buf[200];
61 
62  for (i = 0; i < 8; i++) {
63  if (rates[i].rate == bitrate)
64  return rates[i].mode;
65  if (best < 0 || abs(rates[i].rate - bitrate) < min_diff) {
66  best = i;
67  min_diff = abs(rates[i].rate - bitrate);
68  }
69  }
70  /* no bitrate matching exactly, log a warning */
71  snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
72  for (i = 0; i < 8; i++)
73  av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i].rate / 1000.f);
74  av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best].rate / 1000.f);
75  av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
76 
77  return best;
78 }
79 
80 typedef struct AMRContext {
81  AVClass *av_class;
82  AVFrame frame;
83  void *dec_state;
84  void *enc_state;
85  int enc_bitrate;
86  int enc_mode;
87  int enc_dtx;
88 } AMRContext;
89 
90 static const AVOption options[] = {
91  { "dtx", "Allow DTX (generate comfort noise)", offsetof(AMRContext, enc_dtx), AV_OPT_TYPE_INT, { 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
92  { NULL }
93 };
94 
95 static const AVClass class = {
97 };
98 
99 static av_cold int amr_nb_decode_init(AVCodecContext *avctx)
100 {
101  AMRContext *s = avctx->priv_data;
102 
103  s->dec_state = Decoder_Interface_init();
104  if (!s->dec_state) {
105  av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\n");
106  return -1;
107  }
108 
109  amr_decode_fix_avctx(avctx);
110 
111  if (avctx->channels > 1) {
112  av_log(avctx, AV_LOG_ERROR, "amr_nb: multichannel decoding not supported\n");
113  return AVERROR(ENOSYS);
114  }
115 
117  avctx->coded_frame = &s->frame;
118 
119  return 0;
120 }
121 
122 static av_cold int amr_nb_decode_close(AVCodecContext *avctx)
123 {
124  AMRContext *s = avctx->priv_data;
125 
126  Decoder_Interface_exit(s->dec_state);
127 
128  return 0;
129 }
130 
131 static int amr_nb_decode_frame(AVCodecContext *avctx, void *data,
132  int *got_frame_ptr, AVPacket *avpkt)
133 {
134  const uint8_t *buf = avpkt->data;
135  int buf_size = avpkt->size;
136  AMRContext *s = avctx->priv_data;
137  static const uint8_t block_size[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
138  enum Mode dec_mode;
139  int packet_size, ret;
140 
141  av_dlog(avctx, "amr_decode_frame buf=%p buf_size=%d frame_count=%d!!\n",
142  buf, buf_size, avctx->frame_number);
143 
144  /* get output buffer */
145  s->frame.nb_samples = 160;
146  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
147  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
148  return ret;
149  }
150 
151  dec_mode = (buf[0] >> 3) & 0x000F;
152  packet_size = block_size[dec_mode] + 1;
153 
154  if (packet_size > buf_size) {
155  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
156  buf_size, packet_size);
157  return AVERROR_INVALIDDATA;
158  }
159 
160  av_dlog(avctx, "packet_size=%d buf= 0x%X %X %X %X\n",
161  packet_size, buf[0], buf[1], buf[2], buf[3]);
162  /* call decoder */
163  Decoder_Interface_Decode(s->dec_state, buf, (short *)s->frame.data[0], 0);
164 
165  *got_frame_ptr = 1;
166  *(AVFrame *)data = s->frame;
167 
168  return packet_size;
169 }
170 
171 AVCodec ff_libopencore_amrnb_decoder = {
172  .name = "libopencore_amrnb",
173  .type = AVMEDIA_TYPE_AUDIO,
174  .id = CODEC_ID_AMR_NB,
175  .priv_data_size = sizeof(AMRContext),
176  .init = amr_nb_decode_init,
177  .close = amr_nb_decode_close,
178  .decode = amr_nb_decode_frame,
179  .capabilities = CODEC_CAP_DR1,
180  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
181 };
182 
183 static av_cold int amr_nb_encode_init(AVCodecContext *avctx)
184 {
185  AMRContext *s = avctx->priv_data;
186 
187  if (avctx->sample_rate != 8000) {
188  av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
189  return AVERROR(ENOSYS);
190  }
191 
192  if (avctx->channels != 1) {
193  av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
194  return AVERROR(ENOSYS);
195  }
196 
197  avctx->frame_size = 160;
198  avctx->coded_frame = avcodec_alloc_frame();
199 
200  s->enc_state = Encoder_Interface_init(s->enc_dtx);
201  if (!s->enc_state) {
202  av_log(avctx, AV_LOG_ERROR, "Encoder_Interface_init error\n");
203  return -1;
204  }
205 
206  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
207  s->enc_bitrate = avctx->bit_rate;
208 
209  return 0;
210 }
211 
212 static av_cold int amr_nb_encode_close(AVCodecContext *avctx)
213 {
214  AMRContext *s = avctx->priv_data;
215 
216  Encoder_Interface_exit(s->enc_state);
217  av_freep(&avctx->coded_frame);
218  return 0;
219 }
220 
221 static int amr_nb_encode_frame(AVCodecContext *avctx,
222  unsigned char *frame/*out*/,
223  int buf_size, void *data/*in*/)
224 {
225  AMRContext *s = avctx->priv_data;
226  int written;
227 
228  if (s->enc_bitrate != avctx->bit_rate) {
229  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
230  s->enc_bitrate = avctx->bit_rate;
231  }
232 
233  written = Encoder_Interface_Encode(s->enc_state, s->enc_mode, data,
234  frame, 0);
235  av_dlog(avctx, "amr_nb_encode_frame encoded %u bytes, bitrate %u, first byte was %#02x\n",
236  written, s->enc_mode, frame[0]);
237 
238  return written;
239 }
240 
241 AVCodec ff_libopencore_amrnb_encoder = {
242  .name = "libopencore_amrnb",
243  .type = AVMEDIA_TYPE_AUDIO,
244  .id = CODEC_ID_AMR_NB,
245  .priv_data_size = sizeof(AMRContext),
246  .init = amr_nb_encode_init,
247  .encode = amr_nb_encode_frame,
248  .close = amr_nb_encode_close,
249  .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
250  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
251  .priv_class = &class,
252 };
253 
254 #endif
255 
256 /* -----------AMR wideband ------------*/
257 #if CONFIG_LIBOPENCORE_AMRWB
258 
259 #include <opencore-amrwb/dec_if.h>
260 #include <opencore-amrwb/if_rom.h>
261 
262 typedef struct AMRWBContext {
263  AVFrame frame;
264  void *state;
265 } AMRWBContext;
266 
267 static av_cold int amr_wb_decode_init(AVCodecContext *avctx)
268 {
269  AMRWBContext *s = avctx->priv_data;
270 
271  s->state = D_IF_init();
272 
273  amr_decode_fix_avctx(avctx);
274 
275  if (avctx->channels > 1) {
276  av_log(avctx, AV_LOG_ERROR, "amr_wb: multichannel decoding not supported\n");
277  return AVERROR(ENOSYS);
278  }
279 
281  avctx->coded_frame = &s->frame;
282 
283  return 0;
284 }
285 
286 static int amr_wb_decode_frame(AVCodecContext *avctx, void *data,
287  int *got_frame_ptr, AVPacket *avpkt)
288 {
289  const uint8_t *buf = avpkt->data;
290  int buf_size = avpkt->size;
291  AMRWBContext *s = avctx->priv_data;
292  int mode, ret;
293  int packet_size;
294  static const uint8_t block_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
295 
296  /* get output buffer */
297  s->frame.nb_samples = 320;
298  if ((ret = avctx->get_buffer(avctx, &s->frame)) < 0) {
299  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
300  return ret;
301  }
302 
303  mode = (buf[0] >> 3) & 0x000F;
304  packet_size = block_size[mode];
305 
306  if (packet_size > buf_size) {
307  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
308  buf_size, packet_size + 1);
309  return AVERROR_INVALIDDATA;
310  }
311 
312  D_IF_decode(s->state, buf, (short *)s->frame.data[0], _good_frame);
313 
314  *got_frame_ptr = 1;
315  *(AVFrame *)data = s->frame;
316 
317  return packet_size;
318 }
319 
320 static int amr_wb_decode_close(AVCodecContext *avctx)
321 {
322  AMRWBContext *s = avctx->priv_data;
323 
324  D_IF_exit(s->state);
325  return 0;
326 }
327 
328 AVCodec ff_libopencore_amrwb_decoder = {
329  .name = "libopencore_amrwb",
330  .type = AVMEDIA_TYPE_AUDIO,
331  .id = CODEC_ID_AMR_WB,
332  .priv_data_size = sizeof(AMRWBContext),
333  .init = amr_wb_decode_init,
334  .close = amr_wb_decode_close,
335  .decode = amr_wb_decode_frame,
336  .capabilities = CODEC_CAP_DR1,
337  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Wide-Band"),
338 };
339 
340 #endif /* CONFIG_LIBOPENCORE_AMRWB */