libvorbis.c
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1 /*
2  * copyright (c) 2002 Mark Hills <mark@pogo.org.uk>
3  *
4  * This file is part of Libav.
5  *
6  * Libav is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * Libav is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with Libav; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
27 #include <vorbis/vorbisenc.h>
28 
29 #include "libavutil/opt.h"
30 #include "avcodec.h"
31 #include "bytestream.h"
32 #include "internal.h"
33 #include "vorbis.h"
34 #include "libavutil/mathematics.h"
35 
36 #undef NDEBUG
37 #include <assert.h>
38 
39 #define OGGVORBIS_FRAME_SIZE 64
40 
41 #define BUFFER_SIZE (1024 * 64)
42 
43 typedef struct OggVorbisContext {
45  vorbis_info vi;
46  vorbis_dsp_state vd;
47  vorbis_block vb;
48  uint8_t buffer[BUFFER_SIZE];
50  int eof;
51 
52  /* decoder */
53  vorbis_comment vc;
55 
56  double iblock;
58 
59 static const AVOption options[] = {
60  { "iblock", "Sets the impulse block bias", offsetof(OggVorbisContext, iblock), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, -15, 0, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
61  { NULL }
62 };
63 
64 static const AVCodecDefault defaults[] = {
65  { "b", "0" },
66  { NULL },
67 };
68 
69 static const AVClass class = { "libvorbis", av_default_item_name, options, LIBAVUTIL_VERSION_INT };
70 
71 static av_cold int oggvorbis_init_encoder(vorbis_info *vi, AVCodecContext *avccontext)
72 {
73  OggVorbisContext *context = avccontext->priv_data;
74  double cfreq;
75 
76  if (avccontext->flags & CODEC_FLAG_QSCALE || !avccontext->bit_rate) {
77  /* variable bitrate
78  * NOTE: we use the oggenc range of -1 to 10 for global_quality for
79  * user convenience, but libvorbis uses -0.1 to 1.0.
80  */
81  float q = avccontext->global_quality / (float)FF_QP2LAMBDA;
82  /* default to 3 if the user did not set quality or bitrate */
83  if (!(avccontext->flags & CODEC_FLAG_QSCALE))
84  q = 3.0;
85  if (vorbis_encode_setup_vbr(vi, avccontext->channels,
86  avccontext->sample_rate,
87  q / 10.0))
88  return -1;
89  } else {
90  int minrate = avccontext->rc_min_rate > 0 ? avccontext->rc_min_rate : -1;
91  int maxrate = avccontext->rc_max_rate > 0 ? avccontext->rc_max_rate : -1;
92 
93  /* constant bitrate */
94  if (vorbis_encode_setup_managed(vi, avccontext->channels,
95  avccontext->sample_rate, maxrate,
96  avccontext->bit_rate, minrate))
97  return -1;
98 
99  /* variable bitrate by estimate, disable slow rate management */
100  if (minrate == -1 && maxrate == -1)
101  if (vorbis_encode_ctl(vi, OV_ECTL_RATEMANAGE2_SET, NULL))
102  return -1;
103  }
104 
105  /* cutoff frequency */
106  if (avccontext->cutoff > 0) {
107  cfreq = avccontext->cutoff / 1000.0;
108  if (vorbis_encode_ctl(vi, OV_ECTL_LOWPASS_SET, &cfreq))
109  return -1;
110  }
111 
112  if (context->iblock) {
113  vorbis_encode_ctl(vi, OV_ECTL_IBLOCK_SET, &context->iblock);
114  }
115 
116  return vorbis_encode_setup_init(vi);
117 }
118 
119 /* How many bytes are needed for a buffer of length 'l' */
120 static int xiph_len(int l)
121 {
122  return 1 + l / 255 + l;
123 }
124 
126 {
127  OggVorbisContext *context = avccontext->priv_data;
128  ogg_packet header, header_comm, header_code;
129  uint8_t *p;
130  unsigned int offset;
131 
132  vorbis_info_init(&context->vi);
133  if (oggvorbis_init_encoder(&context->vi, avccontext) < 0) {
134  av_log(avccontext, AV_LOG_ERROR, "oggvorbis_encode_init: init_encoder failed\n");
135  return -1;
136  }
137  vorbis_analysis_init(&context->vd, &context->vi);
138  vorbis_block_init(&context->vd, &context->vb);
139 
140  vorbis_comment_init(&context->vc);
141  vorbis_comment_add_tag(&context->vc, "encoder", LIBAVCODEC_IDENT);
142 
143  vorbis_analysis_headerout(&context->vd, &context->vc, &header,
144  &header_comm, &header_code);
145 
146  avccontext->extradata_size =
147  1 + xiph_len(header.bytes) + xiph_len(header_comm.bytes) +
148  header_code.bytes;
149  p = avccontext->extradata =
151  p[0] = 2;
152  offset = 1;
153  offset += av_xiphlacing(&p[offset], header.bytes);
154  offset += av_xiphlacing(&p[offset], header_comm.bytes);
155  memcpy(&p[offset], header.packet, header.bytes);
156  offset += header.bytes;
157  memcpy(&p[offset], header_comm.packet, header_comm.bytes);
158  offset += header_comm.bytes;
159  memcpy(&p[offset], header_code.packet, header_code.bytes);
160  offset += header_code.bytes;
161  assert(offset == avccontext->extradata_size);
162 
163 #if 0
164  vorbis_block_clear(&context->vb);
165  vorbis_dsp_clear(&context->vd);
166  vorbis_info_clear(&context->vi);
167 #endif
168  vorbis_comment_clear(&context->vc);
169 
170  avccontext->frame_size = OGGVORBIS_FRAME_SIZE;
171 
172  avccontext->coded_frame = avcodec_alloc_frame();
173  avccontext->coded_frame->key_frame = 1;
174 
175  return 0;
176 }
177 
178 static int oggvorbis_encode_frame(AVCodecContext *avccontext,
179  unsigned char *packets,
180  int buf_size, void *data)
181 {
182  OggVorbisContext *context = avccontext->priv_data;
183  ogg_packet op;
184  signed short *audio = data;
185  int l;
186 
187  if (data) {
188  const int samples = avccontext->frame_size;
189  float **buffer;
190  int c, channels = context->vi.channels;
191 
192  buffer = vorbis_analysis_buffer(&context->vd, samples);
193  for (c = 0; c < channels; c++) {
194  int co = (channels > 8) ? c :
196  for (l = 0; l < samples; l++)
197  buffer[c][l] = audio[l * channels + co] / 32768.f;
198  }
199  vorbis_analysis_wrote(&context->vd, samples);
200  } else {
201  if (!context->eof)
202  vorbis_analysis_wrote(&context->vd, 0);
203  context->eof = 1;
204  }
205 
206  while (vorbis_analysis_blockout(&context->vd, &context->vb) == 1) {
207  vorbis_analysis(&context->vb, NULL);
208  vorbis_bitrate_addblock(&context->vb);
209 
210  while (vorbis_bitrate_flushpacket(&context->vd, &op)) {
211  /* i'd love to say the following line is a hack, but sadly it's
212  * not, apparently the end of stream decision is in libogg. */
213  if (op.bytes == 1 && op.e_o_s)
214  continue;
215  if (context->buffer_index + sizeof(ogg_packet) + op.bytes > BUFFER_SIZE) {
216  av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.");
217  return -1;
218  }
219  memcpy(context->buffer + context->buffer_index, &op, sizeof(ogg_packet));
220  context->buffer_index += sizeof(ogg_packet);
221  memcpy(context->buffer + context->buffer_index, op.packet, op.bytes);
222  context->buffer_index += op.bytes;
223 // av_log(avccontext, AV_LOG_DEBUG, "e%d / %d\n", context->buffer_index, op.bytes);
224  }
225  }
226 
227  l = 0;
228  if (context->buffer_index) {
229  ogg_packet *op2 = (ogg_packet *)context->buffer;
230  op2->packet = context->buffer + sizeof(ogg_packet);
231 
232  l = op2->bytes;
233  avccontext->coded_frame->pts = av_rescale_q(op2->granulepos, (AVRational) { 1, avccontext->sample_rate }, avccontext->time_base);
234  //FIXME we should reorder the user supplied pts and not assume that they are spaced by 1/sample_rate
235 
236  if (l > buf_size) {
237  av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.");
238  return -1;
239  }
240 
241  memcpy(packets, op2->packet, l);
242  context->buffer_index -= l + sizeof(ogg_packet);
243  memmove(context->buffer, context->buffer + l + sizeof(ogg_packet), context->buffer_index);
244 // av_log(avccontext, AV_LOG_DEBUG, "E%d\n", l);
245  }
246 
247  return l;
248 }
249 
251 {
252  OggVorbisContext *context = avccontext->priv_data;
253 /* ogg_packet op ; */
254 
255  vorbis_analysis_wrote(&context->vd, 0); /* notify vorbisenc this is EOF */
256 
257  vorbis_block_clear(&context->vb);
258  vorbis_dsp_clear(&context->vd);
259  vorbis_info_clear(&context->vi);
260 
261  av_freep(&avccontext->coded_frame);
262  av_freep(&avccontext->extradata);
263 
264  return 0;
265 }
266 
268  .name = "libvorbis",
269  .type = AVMEDIA_TYPE_AUDIO,
270  .id = CODEC_ID_VORBIS,
271  .priv_data_size = sizeof(OggVorbisContext),
273  .encode = oggvorbis_encode_frame,
275  .capabilities = CODEC_CAP_DELAY,
276  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE },
277  .long_name = NULL_IF_CONFIG_SMALL("libvorbis Vorbis"),
278  .priv_class = &class,
279  .defaults = defaults,
280 };