Libav
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  avpriv_report_missing_feature(avctx, "multi-channel AMR");
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  void *dec_state;
55  void *enc_state;
56  int enc_bitrate;
57  int enc_mode;
58  int enc_dtx;
59  int enc_last_frame;
60  AudioFrameQueue afq;
61 } AMRContext;
62 
63 #if CONFIG_LIBOPENCORE_AMRNB_DECODER
64 static av_cold int amr_nb_decode_init(AVCodecContext *avctx)
65 {
66  AMRContext *s = avctx->priv_data;
67  int ret;
68 
69  if ((ret = amr_decode_fix_avctx(avctx)) < 0)
70  return ret;
71 
72  s->dec_state = Decoder_Interface_init();
73  if (!s->dec_state) {
74  av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\n");
75  return -1;
76  }
77 
78  return 0;
79 }
80 
81 static av_cold int amr_nb_decode_close(AVCodecContext *avctx)
82 {
83  AMRContext *s = avctx->priv_data;
84 
85  Decoder_Interface_exit(s->dec_state);
86 
87  return 0;
88 }
89 
90 static int amr_nb_decode_frame(AVCodecContext *avctx, void *data,
91  int *got_frame_ptr, AVPacket *avpkt)
92 {
93  AVFrame *frame = data;
94  const uint8_t *buf = avpkt->data;
95  int buf_size = avpkt->size;
96  AMRContext *s = avctx->priv_data;
97  static const uint8_t block_size[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
98  enum Mode dec_mode;
99  int packet_size, ret;
100 
101  av_dlog(avctx, "amr_decode_frame buf=%p buf_size=%d frame_count=%d!!\n",
102  buf, buf_size, avctx->frame_number);
103 
104  /* get output buffer */
105  frame->nb_samples = 160;
106  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
107  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
108  return ret;
109  }
110 
111  dec_mode = (buf[0] >> 3) & 0x000F;
112  packet_size = block_size[dec_mode] + 1;
113 
114  if (packet_size > buf_size) {
115  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
116  buf_size, packet_size);
117  return AVERROR_INVALIDDATA;
118  }
119 
120  av_dlog(avctx, "packet_size=%d buf= 0x%X %X %X %X\n",
121  packet_size, buf[0], buf[1], buf[2], buf[3]);
122  /* call decoder */
123  Decoder_Interface_Decode(s->dec_state, buf, (short *)frame->data[0], 0);
124 
125  *got_frame_ptr = 1;
126 
127  return packet_size;
128 }
129 
130 AVCodec ff_libopencore_amrnb_decoder = {
131  .name = "libopencore_amrnb",
132  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-NB (Adaptive Multi-Rate Narrow-Band)"),
133  .type = AVMEDIA_TYPE_AUDIO,
134  .id = AV_CODEC_ID_AMR_NB,
135  .priv_data_size = sizeof(AMRContext),
136  .init = amr_nb_decode_init,
137  .close = amr_nb_decode_close,
138  .decode = amr_nb_decode_frame,
139  .capabilities = CODEC_CAP_DR1,
140 };
141 #endif /* CONFIG_LIBOPENCORE_AMRNB_DECODER */
142 
143 #if CONFIG_LIBOPENCORE_AMRNB_ENCODER
144 /* Common code for fixed and float version*/
145 typedef struct AMR_bitrates {
146  int rate;
147  enum Mode mode;
148 } AMR_bitrates;
149 
150 /* Match desired bitrate */
151 static int get_bitrate_mode(int bitrate, void *log_ctx)
152 {
153  /* make the correspondance between bitrate and mode */
154  static const AMR_bitrates rates[] = {
155  { 4750, MR475 }, { 5150, MR515 }, { 5900, MR59 }, { 6700, MR67 },
156  { 7400, MR74 }, { 7950, MR795 }, { 10200, MR102 }, { 12200, MR122 }
157  };
158  int i, best = -1, min_diff = 0;
159  char log_buf[200];
160 
161  for (i = 0; i < 8; i++) {
162  if (rates[i].rate == bitrate)
163  return rates[i].mode;
164  if (best < 0 || abs(rates[i].rate - bitrate) < min_diff) {
165  best = i;
166  min_diff = abs(rates[i].rate - bitrate);
167  }
168  }
169  /* no bitrate matching exactly, log a warning */
170  snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
171  for (i = 0; i < 8; i++)
172  av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i].rate / 1000.f);
173  av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best].rate / 1000.f);
174  av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
175 
176  return best;
177 }
178 
179 static const AVOption options[] = {
180  { "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 },
181  { NULL }
182 };
183 
184 static const AVClass class = {
185  "libopencore_amrnb", av_default_item_name, options, LIBAVUTIL_VERSION_INT
186 };
187 
188 static av_cold int amr_nb_encode_init(AVCodecContext *avctx)
189 {
190  AMRContext *s = avctx->priv_data;
191 
192  if (avctx->sample_rate != 8000) {
193  av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
194  return AVERROR(ENOSYS);
195  }
196 
197  if (avctx->channels != 1) {
198  av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
199  return AVERROR(ENOSYS);
200  }
201 
202  avctx->frame_size = 160;
203  avctx->delay = 50;
204  ff_af_queue_init(avctx, &s->afq);
205 
206  s->enc_state = Encoder_Interface_init(s->enc_dtx);
207  if (!s->enc_state) {
208  av_log(avctx, AV_LOG_ERROR, "Encoder_Interface_init error\n");
209  av_freep(&avctx->coded_frame);
210  return -1;
211  }
212 
213  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
214  s->enc_bitrate = avctx->bit_rate;
215 
216  return 0;
217 }
218 
219 static av_cold int amr_nb_encode_close(AVCodecContext *avctx)
220 {
221  AMRContext *s = avctx->priv_data;
222 
223  Encoder_Interface_exit(s->enc_state);
224  ff_af_queue_close(&s->afq);
225  return 0;
226 }
227 
228 static int amr_nb_encode_frame(AVCodecContext *avctx, AVPacket *avpkt,
229  const AVFrame *frame, int *got_packet_ptr)
230 {
231  AMRContext *s = avctx->priv_data;
232  int written, ret;
233  int16_t *flush_buf = NULL;
234  const int16_t *samples = frame ? (const int16_t *)frame->data[0] : NULL;
235 
236  if (s->enc_bitrate != avctx->bit_rate) {
237  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
238  s->enc_bitrate = avctx->bit_rate;
239  }
240 
241  if ((ret = ff_alloc_packet(avpkt, 32))) {
242  av_log(avctx, AV_LOG_ERROR, "Error getting output packet\n");
243  return ret;
244  }
245 
246  if (frame) {
247  if (frame->nb_samples < avctx->frame_size) {
248  flush_buf = av_mallocz(avctx->frame_size * sizeof(*flush_buf));
249  if (!flush_buf)
250  return AVERROR(ENOMEM);
251  memcpy(flush_buf, samples, frame->nb_samples * sizeof(*flush_buf));
252  samples = flush_buf;
253  if (frame->nb_samples < avctx->frame_size - avctx->delay)
254  s->enc_last_frame = -1;
255  }
256  if ((ret = ff_af_queue_add(&s->afq, frame)) < 0) {
257  av_freep(&flush_buf);
258  return ret;
259  }
260  } else {
261  if (s->enc_last_frame < 0)
262  return 0;
263  flush_buf = av_mallocz(avctx->frame_size * sizeof(*flush_buf));
264  if (!flush_buf)
265  return AVERROR(ENOMEM);
266  samples = flush_buf;
267  s->enc_last_frame = -1;
268  }
269 
270  written = Encoder_Interface_Encode(s->enc_state, s->enc_mode, samples,
271  avpkt->data, 0);
272  av_dlog(avctx, "amr_nb_encode_frame encoded %u bytes, bitrate %u, first byte was %#02x\n",
273  written, s->enc_mode, frame[0]);
274 
275  /* Get the next frame pts/duration */
276  ff_af_queue_remove(&s->afq, avctx->frame_size, &avpkt->pts,
277  &avpkt->duration);
278 
279  avpkt->size = written;
280  *got_packet_ptr = 1;
281  av_freep(&flush_buf);
282  return 0;
283 }
284 
285 AVCodec ff_libopencore_amrnb_encoder = {
286  .name = "libopencore_amrnb",
287  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-NB (Adaptive Multi-Rate Narrow-Band)"),
288  .type = AVMEDIA_TYPE_AUDIO,
289  .id = AV_CODEC_ID_AMR_NB,
290  .priv_data_size = sizeof(AMRContext),
291  .init = amr_nb_encode_init,
292  .encode2 = amr_nb_encode_frame,
293  .close = amr_nb_encode_close,
295  .sample_fmts = (const enum AVSampleFormat[]){ AV_SAMPLE_FMT_S16,
297  .priv_class = &class,
298 };
299 #endif /* CONFIG_LIBOPENCORE_AMRNB_ENCODER */
300 
301 #endif /* CONFIG_LIBOPENCORE_AMRNB */
302 
303 /* -----------AMR wideband ------------*/
304 #if CONFIG_LIBOPENCORE_AMRWB_DECODER
305 
306 #include <opencore-amrwb/dec_if.h>
307 #include <opencore-amrwb/if_rom.h>
308 
309 typedef struct AMRWBContext {
310  void *state;
311 } AMRWBContext;
312 
313 static av_cold int amr_wb_decode_init(AVCodecContext *avctx)
314 {
315  AMRWBContext *s = avctx->priv_data;
316  int ret;
317 
318  if ((ret = amr_decode_fix_avctx(avctx)) < 0)
319  return ret;
320 
321  s->state = D_IF_init();
322 
323  return 0;
324 }
325 
326 static int amr_wb_decode_frame(AVCodecContext *avctx, void *data,
327  int *got_frame_ptr, AVPacket *avpkt)
328 {
329  AVFrame *frame = data;
330  const uint8_t *buf = avpkt->data;
331  int buf_size = avpkt->size;
332  AMRWBContext *s = avctx->priv_data;
333  int mode, ret;
334  int packet_size;
335  static const uint8_t block_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
336 
337  /* get output buffer */
338  frame->nb_samples = 320;
339  if ((ret = ff_get_buffer(avctx, frame, 0)) < 0) {
340  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
341  return ret;
342  }
343 
344  mode = (buf[0] >> 3) & 0x000F;
345  packet_size = block_size[mode];
346 
347  if (packet_size > buf_size) {
348  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
349  buf_size, packet_size + 1);
350  return AVERROR_INVALIDDATA;
351  }
352 
353  D_IF_decode(s->state, buf, (short *)frame->data[0], _good_frame);
354 
355  *got_frame_ptr = 1;
356 
357  return packet_size;
358 }
359 
360 static int amr_wb_decode_close(AVCodecContext *avctx)
361 {
362  AMRWBContext *s = avctx->priv_data;
363 
364  D_IF_exit(s->state);
365  return 0;
366 }
367 
368 AVCodec ff_libopencore_amrwb_decoder = {
369  .name = "libopencore_amrwb",
370  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE AMR-WB (Adaptive Multi-Rate Wide-Band)"),
371  .type = AVMEDIA_TYPE_AUDIO,
372  .id = AV_CODEC_ID_AMR_WB,
373  .priv_data_size = sizeof(AMRWBContext),
374  .init = amr_wb_decode_init,
375  .close = amr_wb_decode_close,
376  .decode = amr_wb_decode_frame,
377  .capabilities = CODEC_CAP_DR1,
378 };
379 
380 #endif /* CONFIG_LIBOPENCORE_AMRWB_DECODER */