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 "libavutil/avstring.h"
24 #include "libavutil/common.h"
25 #include "libavutil/opt.h"
26 #include "avcodec.h"
27 #include "audio_frame_queue.h"
28 #include "internal.h"
29 
31 {
32  const int is_amr_wb = 1 + (avctx->codec_id == AV_CODEC_ID_AMR_WB);
33 
34  avctx->sample_rate = 8000 * is_amr_wb;
35 
36  if (avctx->channels > 1) {
37  av_log_missing_feature(avctx, "multi-channel AMR", 0);
38  return AVERROR_PATCHWELCOME;
39  }
40 
41  avctx->channels = 1;
44  return 0;
45 }
46 
47 #if CONFIG_LIBOPENCORE_AMRNB
48 
49 #include <opencore-amrnb/interf_dec.h>
50 #include <opencore-amrnb/interf_enc.h>
51 
52 typedef struct AMRContext {
53  AVClass *av_class;
54  AVFrame frame;
55  void *dec_state;
56  void *enc_state;
57  int enc_bitrate;
58  int enc_mode;
59  int enc_dtx;
60  int enc_last_frame;
61  AudioFrameQueue afq;
62 } AMRContext;
63 
64 #if CONFIG_LIBOPENCORE_AMRNB_DECODER
65 static av_cold int amr_nb_decode_init(AVCodecContext *avctx)
66 {
67  AMRContext *s = avctx->priv_data;
68  int ret;
69 
70  if ((ret = amr_decode_fix_avctx(avctx)) < 0)
71  return ret;
72 
73  s->dec_state = Decoder_Interface_init();
74  if (!s->dec_state) {
75  av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\n");
76  return -1;
77  }
78 
80  avctx->coded_frame = &s->frame;
81 
82  return 0;
83 }
84 
85 static av_cold int amr_nb_decode_close(AVCodecContext *avctx)
86 {
87  AMRContext *s = avctx->priv_data;
88 
89  Decoder_Interface_exit(s->dec_state);
90 
91  return 0;
92 }
93 
94 static int amr_nb_decode_frame(AVCodecContext *avctx, void *data,
95  int *got_frame_ptr, AVPacket *avpkt)
96 {
97  const uint8_t *buf = avpkt->data;
98  int buf_size = avpkt->size;
99  AMRContext *s = avctx->priv_data;
100  static const uint8_t block_size[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
101  enum Mode dec_mode;
102  int packet_size, ret;
103 
104  av_dlog(avctx, "amr_decode_frame buf=%p buf_size=%d frame_count=%d!!\n",
105  buf, buf_size, avctx->frame_number);
106 
107  /* get output buffer */
108  s->frame.nb_samples = 160;
109  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
110  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
111  return ret;
112  }
113 
114  dec_mode = (buf[0] >> 3) & 0x000F;
115  packet_size = block_size[dec_mode] + 1;
116 
117  if (packet_size > buf_size) {
118  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
119  buf_size, packet_size);
120  return AVERROR_INVALIDDATA;
121  }
122 
123  av_dlog(avctx, "packet_size=%d buf= 0x%X %X %X %X\n",
124  packet_size, buf[0], buf[1], buf[2], buf[3]);
125  /* call decoder */
126  Decoder_Interface_Decode(s->dec_state, buf, (short *)s->frame.data[0], 0);
127 
128  *got_frame_ptr = 1;
129  *(AVFrame *)data = s->frame;
130 
131  return packet_size;
132 }
133 
134 AVCodec ff_libopencore_amrnb_decoder = {
135  .name = "libopencore_amrnb",
136  .type = AVMEDIA_TYPE_AUDIO,
137  .id = AV_CODEC_ID_AMR_NB,
138  .priv_data_size = sizeof(AMRContext),
139  .init = amr_nb_decode_init,
140  .close = amr_nb_decode_close,
141  .decode = amr_nb_decode_frame,
142  .capabilities = CODEC_CAP_DR1,
143  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-NB (Adaptive Multi-Rate Narrow-Band)"),
144 };
145 #endif /* CONFIG_LIBOPENCORE_AMRNB_DECODER */
146 
147 #if CONFIG_LIBOPENCORE_AMRNB_ENCODER
148 /* Common code for fixed and float version*/
149 typedef struct AMR_bitrates {
150  int rate;
151  enum Mode mode;
152 } AMR_bitrates;
153 
154 /* Match desired bitrate */
155 static int get_bitrate_mode(int bitrate, void *log_ctx)
156 {
157  /* make the correspondance between bitrate and mode */
158  static const AMR_bitrates rates[] = {
159  { 4750, MR475 }, { 5150, MR515 }, { 5900, MR59 }, { 6700, MR67 },
160  { 7400, MR74 }, { 7950, MR795 }, { 10200, MR102 }, { 12200, MR122 }
161  };
162  int i, best = -1, min_diff = 0;
163  char log_buf[200];
164 
165  for (i = 0; i < 8; i++) {
166  if (rates[i].rate == bitrate)
167  return rates[i].mode;
168  if (best < 0 || abs(rates[i].rate - bitrate) < min_diff) {
169  best = i;
170  min_diff = abs(rates[i].rate - bitrate);
171  }
172  }
173  /* no bitrate matching exactly, log a warning */
174  snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
175  for (i = 0; i < 8; i++)
176  av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i].rate / 1000.f);
177  av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best].rate / 1000.f);
178  av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
179 
180  return best;
181 }
182 
183 static const AVOption options[] = {
184  { "dtx", "Allow DTX (generate comfort noise)", offsetof(AMRContext, enc_dtx), AV_OPT_TYPE_INT, { .i64 = 0 }, 0, 1, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
185  { NULL }
186 };
187 
188 static const AVClass class = {
189  "libopencore_amrnb", av_default_item_name, options, LIBAVUTIL_VERSION_INT
190 };
191 
192 static av_cold int amr_nb_encode_init(AVCodecContext *avctx)
193 {
194  AMRContext *s = avctx->priv_data;
195 
196  if (avctx->sample_rate != 8000) {
197  av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
198  return AVERROR(ENOSYS);
199  }
200 
201  if (avctx->channels != 1) {
202  av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
203  return AVERROR(ENOSYS);
204  }
205 
206  avctx->frame_size = 160;
207  avctx->delay = 50;
208  ff_af_queue_init(avctx, &s->afq);
209 #if FF_API_OLD_ENCODE_AUDIO
210  avctx->coded_frame = avcodec_alloc_frame();
211  if (!avctx->coded_frame)
212  return AVERROR(ENOMEM);
213 #endif
214 
215  s->enc_state = Encoder_Interface_init(s->enc_dtx);
216  if (!s->enc_state) {
217  av_log(avctx, AV_LOG_ERROR, "Encoder_Interface_init error\n");
218  av_freep(&avctx->coded_frame);
219  return -1;
220  }
221 
222  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
223  s->enc_bitrate = avctx->bit_rate;
224 
225  return 0;
226 }
227 
228 static av_cold int amr_nb_encode_close(AVCodecContext *avctx)
229 {
230  AMRContext *s = avctx->priv_data;
231 
232  Encoder_Interface_exit(s->enc_state);
233  ff_af_queue_close(&s->afq);
234 #if FF_API_OLD_ENCODE_AUDIO
235  av_freep(&avctx->coded_frame);
236 #endif
237  return 0;
238 }
239 
240 static int amr_nb_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
241  const AVFrame *frame, int *got_packet_ptr)
242 {
243  AMRContext *s = avctx->priv_data;
244  int written, ret;
245  int16_t *flush_buf = NULL;
246  const int16_t *samples = frame ? (const int16_t *)frame->data[0] : NULL;
247 
248  if (s->enc_bitrate != avctx->bit_rate) {
249  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
250  s->enc_bitrate = avctx->bit_rate;
251  }
252 
253  if ((ret = ff_alloc_packet(avpkt, 32))) {
254  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
255  return ret;
256  }
257 
258  if (frame) {
259  if (frame->nb_samples < avctx->frame_size) {
260  flush_buf = av_mallocz(avctx->frame_size * sizeof(*flush_buf));
261  if (!flush_buf)
262  return AVERROR(ENOMEM);
263  memcpy(flush_buf, samples, frame->nb_samples * sizeof(*flush_buf));
264  samples = flush_buf;
265  if (frame->nb_samples < avctx->frame_size - avctx->delay)
266  s->enc_last_frame = -1;
267  }
268  if ((ret = ff_af_queue_add(&s->afq, frame)) < 0) {
269  av_freep(&flush_buf);
270  return ret;
271  }
272  } else {
273  if (s->enc_last_frame < 0)
274  return 0;
275  flush_buf = av_mallocz(avctx->frame_size * sizeof(*flush_buf));
276  if (!flush_buf)
277  return AVERROR(ENOMEM);
278  samples = flush_buf;
279  s->enc_last_frame = -1;
280  }
281 
282  written = Encoder_Interface_Encode(s->enc_state, s->enc_mode, samples,
283  avpkt->data, 0);
284  av_dlog(avctx, "amr_nb_encode_frame encoded %u bytes, bitrate %u, first byte was %#02x\n",
285  written, s->enc_mode, frame[0]);
286 
287  /* Get the next frame pts/duration */
288  ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
289  &avpkt->duration);
290 
291  avpkt->size = written;
292  *got_packet_ptr = 1;
293  av_freep(&flush_buf);
294  return 0;
295 }
296 
297 AVCodec ff_libopencore_amrnb_encoder = {
298  .name = "libopencore_amrnb",
299  .type = AVMEDIA_TYPE_AUDIO,
300  .id = AV_CODEC_ID_AMR_NB,
301  .priv_data_size = sizeof(AMRContext),
302  .init = amr_nb_encode_init,
303  .encode2 = amr_nb_encode_frame,
304  .close = amr_nb_encode_close,
305  .capabilities = CODEC_CAP_DELAY | CODEC_CAP_SMALL_LAST_FRAME,
306  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
308  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-NB (Adaptive Multi-Rate Narrow-Band)"),
309  .priv_class = &class,
310 };
311 #endif /* CONFIG_LIBOPENCORE_AMRNB_ENCODER */
312 
313 #endif /* CONFIG_LIBOPENCORE_AMRNB */
314 
315 /* -----------AMR wideband ------------*/
316 #if CONFIG_LIBOPENCORE_AMRWB_DECODER
317 
318 #include <opencore-amrwb/dec_if.h>
319 #include <opencore-amrwb/if_rom.h>
320 
321 typedef struct AMRWBContext {
322  AVFrame frame;
323  void *state;
324 } AMRWBContext;
325 
326 static av_cold int amr_wb_decode_init(AVCodecContext *avctx)
327 {
328  AMRWBContext *s = avctx->priv_data;
329  int ret;
330 
331  if ((ret = amr_decode_fix_avctx(avctx)) < 0)
332  return ret;
333 
334  s->state = D_IF_init();
335 
337  avctx->coded_frame = &s->frame;
338 
339  return 0;
340 }
341 
342 static int amr_wb_decode_frame(AVCodecContext *avctx, void *data,
343  int *got_frame_ptr, AVPacket *avpkt)
344 {
345  const uint8_t *buf = avpkt->data;
346  int buf_size = avpkt->size;
347  AMRWBContext *s = avctx->priv_data;
348  int mode, ret;
349  int packet_size;
350  static const uint8_t block_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
351 
352  /* get output buffer */
353  s->frame.nb_samples = 320;
354  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
355  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
356  return ret;
357  }
358 
359  mode = (buf[0] >> 3) & 0x000F;
360  packet_size = block_size[mode];
361 
362  if (packet_size > buf_size) {
363  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
364  buf_size, packet_size + 1);
365  return AVERROR_INVALIDDATA;
366  }
367 
368  D_IF_decode(s->state, buf, (short *)s->frame.data[0], _good_frame);
369 
370  *got_frame_ptr = 1;
371  *(AVFrame *)data = s->frame;
372 
373  return packet_size;
374 }
375 
376 static int amr_wb_decode_close(AVCodecContext *avctx)
377 {
378  AMRWBContext *s = avctx->priv_data;
379 
380  D_IF_exit(s->state);
381  return 0;
382 }
383 
384 AVCodec ff_libopencore_amrwb_decoder = {
385  .name = "libopencore_amrwb",
386  .type = AVMEDIA_TYPE_AUDIO,
387  .id = AV_CODEC_ID_AMR_WB,
388  .priv_data_size = sizeof(AMRWBContext),
389  .init = amr_wb_decode_init,
390  .close = amr_wb_decode_close,
391  .decode = amr_wb_decode_frame,
392  .capabilities = CODEC_CAP_DR1,
393  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-WB (Adaptive Multi-Rate Wide-Band)"),
394 };
395 
396 #endif /* CONFIG_LIBOPENCORE_AMRWB_DECODER */