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 "vorbis.h"
33 #include "libavutil/mathematics.h"
34 
35 #undef NDEBUG
36 #include <assert.h>
37 
38 #define OGGVORBIS_FRAME_SIZE 64
39 
40 #define BUFFER_SIZE (1024 * 64)
41 
42 typedef struct OggVorbisContext {
44  vorbis_info vi;
45  vorbis_dsp_state vd;
46  vorbis_block vb;
47  uint8_t buffer[BUFFER_SIZE];
49  int eof;
50 
51  /* decoder */
52  vorbis_comment vc;
54 
55  double iblock;
57 
58 static const AVOption options[] = {
59  { "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 },
60  { NULL }
61 };
62 static const AVClass class = { "libvorbis", av_default_item_name, options, LIBAVUTIL_VERSION_INT };
63 
64 static av_cold int oggvorbis_init_encoder(vorbis_info *vi, AVCodecContext *avccontext)
65 {
66  OggVorbisContext *context = avccontext->priv_data;
67  double cfreq;
68 
69  if (avccontext->flags & CODEC_FLAG_QSCALE) {
70  /* variable bitrate */
71  if (vorbis_encode_setup_vbr(vi, avccontext->channels,
72  avccontext->sample_rate,
73  avccontext->global_quality / (float)FF_QP2LAMBDA / 10.0))
74  return -1;
75  } else {
76  int minrate = avccontext->rc_min_rate > 0 ? avccontext->rc_min_rate : -1;
77  int maxrate = avccontext->rc_min_rate > 0 ? avccontext->rc_max_rate : -1;
78 
79  /* constant bitrate */
80  if (vorbis_encode_setup_managed(vi, avccontext->channels,
81  avccontext->sample_rate, minrate,
82  avccontext->bit_rate, maxrate))
83  return -1;
84 
85  /* variable bitrate by estimate, disable slow rate management */
86  if (minrate == -1 && maxrate == -1)
87  if (vorbis_encode_ctl(vi, OV_ECTL_RATEMANAGE2_SET, NULL))
88  return -1;
89  }
90 
91  /* cutoff frequency */
92  if (avccontext->cutoff > 0) {
93  cfreq = avccontext->cutoff / 1000.0;
94  if (vorbis_encode_ctl(vi, OV_ECTL_LOWPASS_SET, &cfreq))
95  return -1;
96  }
97 
98  if (context->iblock) {
99  vorbis_encode_ctl(vi, OV_ECTL_IBLOCK_SET, &context->iblock);
100  }
101 
102  return vorbis_encode_setup_init(vi);
103 }
104 
105 /* How many bytes are needed for a buffer of length 'l' */
106 static int xiph_len(int l)
107 {
108  return 1 + l / 255 + l;
109 }
110 
112 {
113  OggVorbisContext *context = avccontext->priv_data;
114  ogg_packet header, header_comm, header_code;
115  uint8_t *p;
116  unsigned int offset;
117 
118  vorbis_info_init(&context->vi);
119  if (oggvorbis_init_encoder(&context->vi, avccontext) < 0) {
120  av_log(avccontext, AV_LOG_ERROR, "oggvorbis_encode_init: init_encoder failed\n");
121  return -1;
122  }
123  vorbis_analysis_init(&context->vd, &context->vi);
124  vorbis_block_init(&context->vd, &context->vb);
125 
126  vorbis_comment_init(&context->vc);
127  vorbis_comment_add_tag(&context->vc, "encoder", LIBAVCODEC_IDENT);
128 
129  vorbis_analysis_headerout(&context->vd, &context->vc, &header,
130  &header_comm, &header_code);
131 
132  avccontext->extradata_size =
133  1 + xiph_len(header.bytes) + xiph_len(header_comm.bytes) +
134  header_code.bytes;
135  p = avccontext->extradata =
137  p[0] = 2;
138  offset = 1;
139  offset += av_xiphlacing(&p[offset], header.bytes);
140  offset += av_xiphlacing(&p[offset], header_comm.bytes);
141  memcpy(&p[offset], header.packet, header.bytes);
142  offset += header.bytes;
143  memcpy(&p[offset], header_comm.packet, header_comm.bytes);
144  offset += header_comm.bytes;
145  memcpy(&p[offset], header_code.packet, header_code.bytes);
146  offset += header_code.bytes;
147  assert(offset == avccontext->extradata_size);
148 
149 #if 0
150  vorbis_block_clear(&context->vb);
151  vorbis_dsp_clear(&context->vd);
152  vorbis_info_clear(&context->vi);
153 #endif
154  vorbis_comment_clear(&context->vc);
155 
156  avccontext->frame_size = OGGVORBIS_FRAME_SIZE;
157 
158  avccontext->coded_frame = avcodec_alloc_frame();
159  avccontext->coded_frame->key_frame = 1;
160 
161  return 0;
162 }
163 
164 static int oggvorbis_encode_frame(AVCodecContext *avccontext,
165  unsigned char *packets,
166  int buf_size, void *data)
167 {
168  OggVorbisContext *context = avccontext->priv_data;
169  ogg_packet op;
170  signed short *audio = data;
171  int l;
172 
173  if (data) {
174  const int samples = avccontext->frame_size;
175  float **buffer;
176  int c, channels = context->vi.channels;
177 
178  buffer = vorbis_analysis_buffer(&context->vd, samples);
179  for (c = 0; c < channels; c++) {
180  int co = (channels > 8) ? c :
182  for (l = 0; l < samples; l++)
183  buffer[c][l] = audio[l * channels + co] / 32768.f;
184  }
185  vorbis_analysis_wrote(&context->vd, samples);
186  } else {
187  if (!context->eof)
188  vorbis_analysis_wrote(&context->vd, 0);
189  context->eof = 1;
190  }
191 
192  while (vorbis_analysis_blockout(&context->vd, &context->vb) == 1) {
193  vorbis_analysis(&context->vb, NULL);
194  vorbis_bitrate_addblock(&context->vb);
195 
196  while (vorbis_bitrate_flushpacket(&context->vd, &op)) {
197  /* i'd love to say the following line is a hack, but sadly it's
198  * not, apparently the end of stream decision is in libogg. */
199  if (op.bytes == 1 && op.e_o_s)
200  continue;
201  if (context->buffer_index + sizeof(ogg_packet) + op.bytes > BUFFER_SIZE) {
202  av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.");
203  return -1;
204  }
205  memcpy(context->buffer + context->buffer_index, &op, sizeof(ogg_packet));
206  context->buffer_index += sizeof(ogg_packet);
207  memcpy(context->buffer + context->buffer_index, op.packet, op.bytes);
208  context->buffer_index += op.bytes;
209 // av_log(avccontext, AV_LOG_DEBUG, "e%d / %d\n", context->buffer_index, op.bytes);
210  }
211  }
212 
213  l = 0;
214  if (context->buffer_index) {
215  ogg_packet *op2 = (ogg_packet *)context->buffer;
216  op2->packet = context->buffer + sizeof(ogg_packet);
217 
218  l = op2->bytes;
219  avccontext->coded_frame->pts = av_rescale_q(op2->granulepos, (AVRational) { 1, avccontext->sample_rate }, avccontext->time_base);
220  //FIXME we should reorder the user supplied pts and not assume that they are spaced by 1/sample_rate
221 
222  if (l > buf_size) {
223  av_log(avccontext, AV_LOG_ERROR, "libvorbis: buffer overflow.");
224  return -1;
225  }
226 
227  memcpy(packets, op2->packet, l);
228  context->buffer_index -= l + sizeof(ogg_packet);
229  memmove(context->buffer, context->buffer + l + sizeof(ogg_packet), context->buffer_index);
230 // av_log(avccontext, AV_LOG_DEBUG, "E%d\n", l);
231  }
232 
233  return l;
234 }
235 
237 {
238  OggVorbisContext *context = avccontext->priv_data;
239 /* ogg_packet op ; */
240 
241  vorbis_analysis_wrote(&context->vd, 0); /* notify vorbisenc this is EOF */
242 
243  vorbis_block_clear(&context->vb);
244  vorbis_dsp_clear(&context->vd);
245  vorbis_info_clear(&context->vi);
246 
247  av_freep(&avccontext->coded_frame);
248  av_freep(&avccontext->extradata);
249 
250  return 0;
251 }
252 
254  .name = "libvorbis",
255  .type = AVMEDIA_TYPE_AUDIO,
256  .id = CODEC_ID_VORBIS,
257  .priv_data_size = sizeof(OggVorbisContext),
259  .encode = oggvorbis_encode_frame,
261  .capabilities = CODEC_CAP_DELAY,
262  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_S16, AV_SAMPLE_FMT_NONE },
263  .long_name = NULL_IF_CONFIG_SMALL("libvorbis Vorbis"),
264  .priv_class = &class,
265 };