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 "internal.h"
24 #include "libavutil/avstring.h"
25 #include "libavutil/opt.h"
26 
28 {
29  const int is_amr_wb = 1 + (avctx->codec_id == CODEC_ID_AMR_WB);
30 
31  if (!avctx->sample_rate)
32  avctx->sample_rate = 8000 * is_amr_wb;
33 
34  if (!avctx->channels)
35  avctx->channels = 1;
36 
37  avctx->frame_size = 160 * is_amr_wb;
39 }
40 
41 #if CONFIG_LIBOPENCORE_AMRNB
42 
43 #include <opencore-amrnb/interf_dec.h>
44 #include <opencore-amrnb/interf_enc.h>
45 
46 /* Common code for fixed and float version*/
47 typedef struct AMR_bitrates {
48  int rate;
49  enum Mode mode;
50 } AMR_bitrates;
51 
52 /* Match desired bitrate */
53 static int get_bitrate_mode(int bitrate, void *log_ctx)
54 {
55  /* make the correspondance between bitrate and mode */
56  static const AMR_bitrates rates[] = {
57  { 4750, MR475 }, { 5150, MR515 }, { 5900, MR59 }, { 6700, MR67 },
58  { 7400, MR74 }, { 7950, MR795 }, { 10200, MR102 }, { 12200, MR122 }
59  };
60  int i, best = -1, min_diff = 0;
61  char log_buf[200];
62 
63  for (i = 0; i < 8; i++) {
64  if (rates[i].rate == bitrate)
65  return rates[i].mode;
66  if (best < 0 || abs(rates[i].rate - bitrate) < min_diff) {
67  best = i;
68  min_diff = abs(rates[i].rate - bitrate);
69  }
70  }
71  /* no bitrate matching exactly, log a warning */
72  snprintf(log_buf, sizeof(log_buf), "bitrate not supported: use one of ");
73  for (i = 0; i < 8; i++)
74  av_strlcatf(log_buf, sizeof(log_buf), "%.2fk, ", rates[i].rate / 1000.f);
75  av_strlcatf(log_buf, sizeof(log_buf), "using %.2fk", rates[best].rate / 1000.f);
76  av_log(log_ctx, AV_LOG_WARNING, "%s\n", log_buf);
77 
78  return best;
79 }
80 
81 typedef struct AMRContext {
82  AVClass *av_class;
83  AVFrame frame;
84  void *dec_state;
85  void *enc_state;
86  int enc_bitrate;
87  int enc_mode;
88  int enc_dtx;
89 } AMRContext;
90 
91 static const AVOption options[] = {
92  { "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 },
93  { NULL }
94 };
95 
96 static const AVClass class = {
98 };
99 
100 static av_cold int amr_nb_decode_init(AVCodecContext *avctx)
101 {
102  AMRContext *s = avctx->priv_data;
103 
104  s->dec_state = Decoder_Interface_init();
105  if (!s->dec_state) {
106  av_log(avctx, AV_LOG_ERROR, "Decoder_Interface_init error\n");
107  return -1;
108  }
109 
110  amr_decode_fix_avctx(avctx);
111 
112  if (avctx->channels > 1) {
113  av_log(avctx, AV_LOG_ERROR, "amr_nb: multichannel decoding not supported\n");
114  return AVERROR(ENOSYS);
115  }
116 
118  avctx->coded_frame = &s->frame;
119 
120  return 0;
121 }
122 
123 static av_cold int amr_nb_decode_close(AVCodecContext *avctx)
124 {
125  AMRContext *s = avctx->priv_data;
126 
127  Decoder_Interface_exit(s->dec_state);
128 
129  return 0;
130 }
131 
132 static int amr_nb_decode_frame(AVCodecContext *avctx, void *data,
133  int *got_frame_ptr, AVPacket *avpkt)
134 {
135  const uint8_t *buf = avpkt->data;
136  int buf_size = avpkt->size;
137  AMRContext *s = avctx->priv_data;
138  static const uint8_t block_size[16] = { 12, 13, 15, 17, 19, 20, 26, 31, 5, 0, 0, 0, 0, 0, 0, 0 };
139  enum Mode dec_mode;
140  int packet_size, ret;
141 
142  av_dlog(avctx, "amr_decode_frame buf=%p buf_size=%d frame_count=%d!!\n",
143  buf, buf_size, avctx->frame_number);
144 
145  /* get output buffer */
146  s->frame.nb_samples = 160;
147  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
148  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
149  return ret;
150  }
151 
152  dec_mode = (buf[0] >> 3) & 0x000F;
153  packet_size = block_size[dec_mode] + 1;
154 
155  if (packet_size > buf_size) {
156  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
157  buf_size, packet_size);
158  return AVERROR_INVALIDDATA;
159  }
160 
161  av_dlog(avctx, "packet_size=%d buf= 0x%X %X %X %X\n",
162  packet_size, buf[0], buf[1], buf[2], buf[3]);
163  /* call decoder */
164  Decoder_Interface_Decode(s->dec_state, buf, (short *)s->frame.data[0], 0);
165 
166  *got_frame_ptr = 1;
167  *(AVFrame *)data = s->frame;
168 
169  return packet_size;
170 }
171 
172 AVCodec ff_libopencore_amrnb_decoder = {
173  .name = "libopencore_amrnb",
174  .type = AVMEDIA_TYPE_AUDIO,
175  .id = CODEC_ID_AMR_NB,
176  .priv_data_size = sizeof(AMRContext),
177  .init = amr_nb_decode_init,
178  .close = amr_nb_decode_close,
179  .decode = amr_nb_decode_frame,
180  .capabilities = CODEC_CAP_DR1,
181  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
182 };
183 
184 static av_cold int amr_nb_encode_init(AVCodecContext *avctx)
185 {
186  AMRContext *s = avctx->priv_data;
187 
188  if (avctx->sample_rate != 8000) {
189  av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
190  return AVERROR(ENOSYS);
191  }
192 
193  if (avctx->channels != 1) {
194  av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
195  return AVERROR(ENOSYS);
196  }
197 
198  avctx->frame_size = 160;
199  avctx->coded_frame = avcodec_alloc_frame();
200 
201  s->enc_state = Encoder_Interface_init(s->enc_dtx);
202  if (!s->enc_state) {
203  av_log(avctx, AV_LOG_ERROR, "Encoder_Interface_init error\n");
204  return -1;
205  }
206 
207  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
208  s->enc_bitrate = avctx->bit_rate;
209 
210  return 0;
211 }
212 
213 static av_cold int amr_nb_encode_close(AVCodecContext *avctx)
214 {
215  AMRContext *s = avctx->priv_data;
216 
217  Encoder_Interface_exit(s->enc_state);
218  av_freep(&avctx->coded_frame);
219  return 0;
220 }
221 
222 static int amr_nb_encode_frame(AVCodecContext *avctx,
223  unsigned char *frame/*out*/,
224  int buf_size, void *data/*in*/)
225 {
226  AMRContext *s = avctx->priv_data;
227  int written;
228 
229  if (s->enc_bitrate != avctx->bit_rate) {
230  s->enc_mode = get_bitrate_mode(avctx->bit_rate, avctx);
231  s->enc_bitrate = avctx->bit_rate;
232  }
233 
234  written = Encoder_Interface_Encode(s->enc_state, s->enc_mode, data,
235  frame, 0);
236  av_dlog(avctx, "amr_nb_encode_frame encoded %u bytes, bitrate %u, first byte was %#02x\n",
237  written, s->enc_mode, frame[0]);
238 
239  return written;
240 }
241 
242 AVCodec ff_libopencore_amrnb_encoder = {
243  .name = "libopencore_amrnb",
244  .type = AVMEDIA_TYPE_AUDIO,
245  .id = CODEC_ID_AMR_NB,
246  .priv_data_size = sizeof(AMRContext),
247  .init = amr_nb_encode_init,
248  .encode = amr_nb_encode_frame,
249  .close = amr_nb_encode_close,
250  .sample_fmts = (const enum AVSampleFormat[]){AV_SAMPLE_FMT_S16,AV_SAMPLE_FMT_NONE},
251  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Narrow-Band"),
252  .priv_class = &class,
253 };
254 
255 #endif
256 
257 /* -----------AMR wideband ------------*/
258 #if CONFIG_LIBOPENCORE_AMRWB
259 
260 #include <opencore-amrwb/dec_if.h>
261 #include <opencore-amrwb/if_rom.h>
262 
263 typedef struct AMRWBContext {
264  AVFrame frame;
265  void *state;
266 } AMRWBContext;
267 
268 static av_cold int amr_wb_decode_init(AVCodecContext *avctx)
269 {
270  AMRWBContext *s = avctx->priv_data;
271 
272  s->state = D_IF_init();
273 
274  amr_decode_fix_avctx(avctx);
275 
276  if (avctx->channels > 1) {
277  av_log(avctx, AV_LOG_ERROR, "amr_wb: multichannel decoding not supported\n");
278  return AVERROR(ENOSYS);
279  }
280 
282  avctx->coded_frame = &s->frame;
283 
284  return 0;
285 }
286 
287 static int amr_wb_decode_frame(AVCodecContext *avctx, void *data,
288  int *got_frame_ptr, AVPacket *avpkt)
289 {
290  const uint8_t *buf = avpkt->data;
291  int buf_size = avpkt->size;
292  AMRWBContext *s = avctx->priv_data;
293  int mode, ret;
294  int packet_size;
295  static const uint8_t block_size[16] = {18, 24, 33, 37, 41, 47, 51, 59, 61, 6, 6, 0, 0, 0, 1, 1};
296 
297  /* get output buffer */
298  s->frame.nb_samples = 320;
299  if ((ret = ff_get_buffer(avctx, &s->frame)) < 0) {
300  av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
301  return ret;
302  }
303 
304  mode = (buf[0] >> 3) & 0x000F;
305  packet_size = block_size[mode];
306 
307  if (packet_size > buf_size) {
308  av_log(avctx, AV_LOG_ERROR, "amr frame too short (%u, should be %u)\n",
309  buf_size, packet_size + 1);
310  return AVERROR_INVALIDDATA;
311  }
312 
313  D_IF_decode(s->state, buf, (short *)s->frame.data[0], _good_frame);
314 
315  *got_frame_ptr = 1;
316  *(AVFrame *)data = s->frame;
317 
318  return packet_size;
319 }
320 
321 static int amr_wb_decode_close(AVCodecContext *avctx)
322 {
323  AMRWBContext *s = avctx->priv_data;
324 
325  D_IF_exit(s->state);
326  return 0;
327 }
328 
329 AVCodec ff_libopencore_amrwb_decoder = {
330  .name = "libopencore_amrwb",
331  .type = AVMEDIA_TYPE_AUDIO,
332  .id = CODEC_ID_AMR_WB,
333  .priv_data_size = sizeof(AMRWBContext),
334  .init = amr_wb_decode_init,
335  .close = amr_wb_decode_close,
336  .decode = amr_wb_decode_frame,
337  .capabilities = CODEC_CAP_DR1,
338  .long_name = NULL_IF_CONFIG_SMALL("OpenCORE Adaptive Multi-Rate (AMR) Wide-Band"),
339 };
340 
341 #endif /* CONFIG_LIBOPENCORE_AMRWB */