FFmpeg
libvorbisenc.c
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1 /*
2  * Copyright (c) 2002 Mark Hills <mark@pogo.org.uk>
3  *
4  * This file is part of FFmpeg.
5  *
6  * FFmpeg 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  * FFmpeg 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 FFmpeg; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
19  */
20 
21 #include <vorbis/vorbisenc.h>
22 
23 #include "libavutil/avassert.h"
24 #include "libavutil/fifo.h"
25 #include "libavutil/opt.h"
26 #include "avcodec.h"
27 #include "audio_frame_queue.h"
28 #include "internal.h"
29 #include "vorbis.h"
30 #include "vorbis_parser.h"
31 
32 
33 /* Number of samples the user should send in each call.
34  * This value is used because it is the LCD of all possible frame sizes, so
35  * an output packet will always start at the same point as one of the input
36  * packets.
37  */
38 #define LIBVORBIS_FRAME_SIZE 64
39 
40 #define BUFFER_SIZE (1024 * 64)
41 
42 typedef struct LibvorbisEncContext {
43  AVClass *av_class; /**< class for AVOptions */
44  vorbis_info vi; /**< vorbis_info used during init */
45  vorbis_dsp_state vd; /**< DSP state used for analysis */
46  vorbis_block vb; /**< vorbis_block used for analysis */
47  AVFifoBuffer *pkt_fifo; /**< output packet buffer */
48  int eof; /**< end-of-file flag */
49  int dsp_initialized; /**< vd has been initialized */
50  vorbis_comment vc; /**< VorbisComment info */
51  double iblock; /**< impulse block bias option */
52  AVVorbisParseContext *vp; /**< parse context to get durations */
53  AudioFrameQueue afq; /**< frame queue for timestamps */
55 
56 static const AVOption options[] = {
57  { "iblock", "Sets the impulse block bias", offsetof(LibvorbisEncContext, iblock), AV_OPT_TYPE_DOUBLE, { .dbl = 0 }, -15, 0, AV_OPT_FLAG_AUDIO_PARAM | AV_OPT_FLAG_ENCODING_PARAM },
58  { NULL }
59 };
60 
61 static const AVCodecDefault defaults[] = {
62  { "b", "0" },
63  { NULL },
64 };
65 
66 static const AVClass vorbis_class = {
67  .class_name = "libvorbis",
68  .item_name = av_default_item_name,
69  .option = options,
70  .version = LIBAVUTIL_VERSION_INT,
71 };
72 
73 static const uint8_t vorbis_encoding_channel_layout_offsets[8][8] = {
74  { 0 },
75  { 0, 1 },
76  { 0, 2, 1 },
77  { 0, 1, 2, 3 },
78  { 0, 2, 1, 3, 4 },
79  { 0, 2, 1, 4, 5, 3 },
80  { 0, 2, 1, 5, 6, 4, 3 },
81  { 0, 2, 1, 6, 7, 4, 5, 3 },
82 };
83 
84 static int vorbis_error_to_averror(int ov_err)
85 {
86  switch (ov_err) {
87  case OV_EFAULT: return AVERROR_BUG;
88  case OV_EINVAL: return AVERROR(EINVAL);
89  case OV_EIMPL: return AVERROR(EINVAL);
90  default: return AVERROR_UNKNOWN;
91  }
92 }
93 
94 static av_cold int libvorbis_setup(vorbis_info *vi, AVCodecContext *avctx)
95 {
97  double cfreq;
98  int ret;
99 
100  if (avctx->flags & AV_CODEC_FLAG_QSCALE || !avctx->bit_rate) {
101  /* variable bitrate
102  * NOTE: we use the oggenc range of -1 to 10 for global_quality for
103  * user convenience, but libvorbis uses -0.1 to 1.0.
104  */
105  float q = avctx->global_quality / (float)FF_QP2LAMBDA;
106  /* default to 3 if the user did not set quality or bitrate */
107  if (!(avctx->flags & AV_CODEC_FLAG_QSCALE))
108  q = 3.0;
109  if ((ret = vorbis_encode_setup_vbr(vi, avctx->channels,
110  avctx->sample_rate,
111  q / 10.0)))
112  goto error;
113  } else {
114  int minrate = avctx->rc_min_rate > 0 ? avctx->rc_min_rate : -1;
115  int maxrate = avctx->rc_max_rate > 0 ? avctx->rc_max_rate : -1;
116 
117  /* average bitrate */
118  if ((ret = vorbis_encode_setup_managed(vi, avctx->channels,
119  avctx->sample_rate, maxrate,
120  avctx->bit_rate, minrate)))
121  goto error;
122 
123  /* variable bitrate by estimate, disable slow rate management */
124  if (minrate == -1 && maxrate == -1)
125  if ((ret = vorbis_encode_ctl(vi, OV_ECTL_RATEMANAGE2_SET, NULL)))
126  goto error; /* should not happen */
127  }
128 
129  /* cutoff frequency */
130  if (avctx->cutoff > 0) {
131  cfreq = avctx->cutoff / 1000.0;
132  if ((ret = vorbis_encode_ctl(vi, OV_ECTL_LOWPASS_SET, &cfreq)))
133  goto error; /* should not happen */
134  }
135 
136  /* impulse block bias */
137  if (s->iblock) {
138  if ((ret = vorbis_encode_ctl(vi, OV_ECTL_IBLOCK_SET, &s->iblock)))
139  goto error;
140  }
141 
142  if (avctx->channels == 3 &&
144  avctx->channels == 4 &&
145  avctx->channel_layout != AV_CH_LAYOUT_2_2 &&
146  avctx->channel_layout != AV_CH_LAYOUT_QUAD ||
147  avctx->channels == 5 &&
150  avctx->channels == 6 &&
153  avctx->channels == 7 &&
155  avctx->channels == 8 &&
157  if (avctx->channel_layout) {
158  char name[32];
160  avctx->channel_layout);
161  av_log(avctx, AV_LOG_ERROR, "%s not supported by Vorbis: "
162  "output stream will have incorrect "
163  "channel layout.\n", name);
164  } else {
165  av_log(avctx, AV_LOG_WARNING, "No channel layout specified. The encoder "
166  "will use Vorbis channel layout for "
167  "%d channels.\n", avctx->channels);
168  }
169  }
170 
171  if ((ret = vorbis_encode_setup_init(vi)))
172  goto error;
173 
174  return 0;
175 error:
177 }
178 
179 /* How many bytes are needed for a buffer of length 'l' */
180 static int xiph_len(int l)
181 {
182  return 1 + l / 255 + l;
183 }
184 
186 {
187  LibvorbisEncContext *s = avctx->priv_data;
188 
189  /* notify vorbisenc this is EOF */
190  if (s->dsp_initialized)
191  vorbis_analysis_wrote(&s->vd, 0);
192 
193  vorbis_block_clear(&s->vb);
194  vorbis_dsp_clear(&s->vd);
195  vorbis_info_clear(&s->vi);
196 
197  av_fifo_freep(&s->pkt_fifo);
198  ff_af_queue_close(&s->afq);
199 
200  av_vorbis_parse_free(&s->vp);
201 
202  return 0;
203 }
204 
206 {
207  LibvorbisEncContext *s = avctx->priv_data;
208  ogg_packet header, header_comm, header_code;
209  uint8_t *p;
210  unsigned int offset;
211  int ret;
212 
213  vorbis_info_init(&s->vi);
214  if ((ret = libvorbis_setup(&s->vi, avctx))) {
215  av_log(avctx, AV_LOG_ERROR, "encoder setup failed\n");
216  goto error;
217  }
218  if ((ret = vorbis_analysis_init(&s->vd, &s->vi))) {
219  av_log(avctx, AV_LOG_ERROR, "analysis init failed\n");
221  goto error;
222  }
223  s->dsp_initialized = 1;
224  if ((ret = vorbis_block_init(&s->vd, &s->vb))) {
225  av_log(avctx, AV_LOG_ERROR, "dsp init failed\n");
227  goto error;
228  }
229 
230  vorbis_comment_init(&s->vc);
231  if (!(avctx->flags & AV_CODEC_FLAG_BITEXACT))
232  vorbis_comment_add_tag(&s->vc, "encoder", LIBAVCODEC_IDENT);
233 
234  if ((ret = vorbis_analysis_headerout(&s->vd, &s->vc, &header, &header_comm,
235  &header_code))) {
237  goto error;
238  }
239 
240  avctx->extradata_size = 1 + xiph_len(header.bytes) +
241  xiph_len(header_comm.bytes) +
242  header_code.bytes;
243  p = avctx->extradata = av_malloc(avctx->extradata_size +
245  if (!p) {
246  ret = AVERROR(ENOMEM);
247  goto error;
248  }
249  p[0] = 2;
250  offset = 1;
251  offset += av_xiphlacing(&p[offset], header.bytes);
252  offset += av_xiphlacing(&p[offset], header_comm.bytes);
253  memcpy(&p[offset], header.packet, header.bytes);
254  offset += header.bytes;
255  memcpy(&p[offset], header_comm.packet, header_comm.bytes);
256  offset += header_comm.bytes;
257  memcpy(&p[offset], header_code.packet, header_code.bytes);
258  offset += header_code.bytes;
259  av_assert0(offset == avctx->extradata_size);
260 
261  s->vp = av_vorbis_parse_init(avctx->extradata, avctx->extradata_size);
262  if (!s->vp) {
263  av_log(avctx, AV_LOG_ERROR, "invalid extradata\n");
264  return ret;
265  }
266 
267  vorbis_comment_clear(&s->vc);
268 
270  ff_af_queue_init(avctx, &s->afq);
271 
272  s->pkt_fifo = av_fifo_alloc(BUFFER_SIZE);
273  if (!s->pkt_fifo) {
274  ret = AVERROR(ENOMEM);
275  goto error;
276  }
277 
278  return 0;
279 error:
280  libvorbis_encode_close(avctx);
281  return ret;
282 }
283 
285  const AVFrame *frame, int *got_packet_ptr)
286 {
287  LibvorbisEncContext *s = avctx->priv_data;
288  ogg_packet op;
289  int ret, duration;
290 
291  /* send samples to libvorbis */
292  if (frame) {
293  const int samples = frame->nb_samples;
294  float **buffer;
295  int c, channels = s->vi.channels;
296 
297  buffer = vorbis_analysis_buffer(&s->vd, samples);
298  for (c = 0; c < channels; c++) {
299  int co = (channels > 8) ? c :
301  memcpy(buffer[c], frame->extended_data[co],
302  samples * sizeof(*buffer[c]));
303  }
304  if ((ret = vorbis_analysis_wrote(&s->vd, samples)) < 0) {
305  av_log(avctx, AV_LOG_ERROR, "error in vorbis_analysis_wrote()\n");
307  }
308  if ((ret = ff_af_queue_add(&s->afq, frame)) < 0)
309  return ret;
310  } else {
311  if (!s->eof && s->afq.frame_alloc)
312  if ((ret = vorbis_analysis_wrote(&s->vd, 0)) < 0) {
313  av_log(avctx, AV_LOG_ERROR, "error in vorbis_analysis_wrote()\n");
315  }
316  s->eof = 1;
317  }
318 
319  /* retrieve available packets from libvorbis */
320  while ((ret = vorbis_analysis_blockout(&s->vd, &s->vb)) == 1) {
321  if ((ret = vorbis_analysis(&s->vb, NULL)) < 0)
322  break;
323  if ((ret = vorbis_bitrate_addblock(&s->vb)) < 0)
324  break;
325 
326  /* add any available packets to the output packet buffer */
327  while ((ret = vorbis_bitrate_flushpacket(&s->vd, &op)) == 1) {
328  if (av_fifo_space(s->pkt_fifo) < sizeof(ogg_packet) + op.bytes) {
329  av_log(avctx, AV_LOG_ERROR, "packet buffer is too small\n");
330  return AVERROR_BUG;
331  }
332  av_fifo_generic_write(s->pkt_fifo, &op, sizeof(ogg_packet), NULL);
333  av_fifo_generic_write(s->pkt_fifo, op.packet, op.bytes, NULL);
334  }
335  if (ret < 0) {
336  av_log(avctx, AV_LOG_ERROR, "error getting available packets\n");
337  break;
338  }
339  }
340  if (ret < 0) {
341  av_log(avctx, AV_LOG_ERROR, "error getting available packets\n");
343  }
344 
345  /* check for available packets */
346  if (av_fifo_size(s->pkt_fifo) < sizeof(ogg_packet))
347  return 0;
348 
349  av_fifo_generic_read(s->pkt_fifo, &op, sizeof(ogg_packet), NULL);
350 
351  if ((ret = ff_alloc_packet2(avctx, avpkt, op.bytes, 0)) < 0)
352  return ret;
353  av_fifo_generic_read(s->pkt_fifo, avpkt->data, op.bytes, NULL);
354 
355  avpkt->pts = ff_samples_to_time_base(avctx, op.granulepos);
356 
357  duration = av_vorbis_parse_frame(s->vp, avpkt->data, avpkt->size);
358  if (duration > 0) {
359  /* we do not know encoder delay until we get the first packet from
360  * libvorbis, so we have to update the AudioFrameQueue counts */
361  if (!avctx->initial_padding && s->afq.frames) {
362  avctx->initial_padding = duration;
363  av_assert0(!s->afq.remaining_delay);
364  s->afq.frames->duration += duration;
365  if (s->afq.frames->pts != AV_NOPTS_VALUE)
366  s->afq.frames->pts -= duration;
367  s->afq.remaining_samples += duration;
368  }
369  ff_af_queue_remove(&s->afq, duration, &avpkt->pts, &avpkt->duration);
370  }
371 
372  *got_packet_ptr = 1;
373  return 0;
374 }
375 
377  .name = "libvorbis",
378  .long_name = NULL_IF_CONFIG_SMALL("libvorbis"),
379  .type = AVMEDIA_TYPE_AUDIO,
380  .id = AV_CODEC_ID_VORBIS,
381  .priv_data_size = sizeof(LibvorbisEncContext),
383  .encode2 = libvorbis_encode_frame,
384  .close = libvorbis_encode_close,
386  .sample_fmts = (const enum AVSampleFormat[]) { AV_SAMPLE_FMT_FLTP,
388  .priv_class = &vorbis_class,
389  .defaults = defaults,
390  .wrapper_name = "libvorbis",
391 };
error
static void error(const char *err)
Definition: target_bsf_fuzzer.c:30
AVCodecContext::frame_size
int frame_size
Number of samples per channel in an audio frame.
Definition: avcodec.h:1118
AVCodec
AVCodec.
Definition: codec.h:197
AV_SAMPLE_FMT_FLTP
@ AV_SAMPLE_FMT_FLTP
float, planar
Definition: samplefmt.h:69
AV_LOG_WARNING
#define AV_LOG_WARNING
Something somehow does not look correct.
Definition: log.h:187
name
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf default minimum maximum flags name is the option name
Definition: writing_filters.txt:88
LibvorbisEncContext::vc
vorbis_comment vc
VorbisComment info
Definition: libvorbisenc.c:50
AV_CH_LAYOUT_5POINT0_BACK
#define AV_CH_LAYOUT_5POINT0_BACK
Definition: channel_layout.h:102
init
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:31
av_vorbis_parse_free
void av_vorbis_parse_free(AVVorbisParseContext **s)
Free the parser and everything associated with it.
Definition: vorbis_parser.c:276
AVERROR
Filter the word “frame” indicates either a video frame or a group of audio as stored in an AVFrame structure Format for each input and each output the list of supported formats For video that means pixel format For audio that means channel sample they are references to shared objects When the negotiation mechanism computes the intersection of the formats supported at each end of a all references to both lists are replaced with a reference to the intersection And when a single format is eventually chosen for a link amongst the remaining all references to the list are updated That means that if a filter requires that its input and output have the same format amongst a supported all it has to do is use a reference to the same list of formats query_formats can leave some formats unset and return AVERROR(EAGAIN) to cause the negotiation mechanism toagain later. That can be used by filters with complex requirements to use the format negotiated on one link to set the formats supported on another. Frame references ownership and permissions
opt.h
av_xiphlacing
unsigned int av_xiphlacing(unsigned char *s, unsigned int v)
Encode extradata length to a buffer.
Definition: utils.c:827
LIBAVCODEC_IDENT
#define LIBAVCODEC_IDENT
Definition: version.h:42
AVCodecContext::channel_layout
uint64_t channel_layout
Audio channel layout.
Definition: avcodec.h:1149
av_fifo_generic_write
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int(*func)(void *, void *, int))
Feed data from a user-supplied callback to an AVFifoBuffer.
Definition: fifo.c:122
ff_af_queue_remove
void ff_af_queue_remove(AudioFrameQueue *afq, int nb_samples, int64_t *pts, int64_t *duration)
Remove frame(s) from the queue.
Definition: audio_frame_queue.c:75
AVCodecContext::sample_rate
int sample_rate
samples per second
Definition: avcodec.h:1098
AVVorbisParseContext
Definition: vorbis_parser_internal.h:34
AVCodecContext::rc_min_rate
int64_t rc_min_rate
minimum bitrate
Definition: avcodec.h:1307
defaults
static const AVCodecDefault defaults[]
Definition: libvorbisenc.c:61
ff_af_queue_close
void ff_af_queue_close(AudioFrameQueue *afq)
Close AudioFrameQueue.
Definition: audio_frame_queue.c:36
sample_fmts
static enum AVSampleFormat sample_fmts[]
Definition: adpcmenc.c:953
AV_CODEC_FLAG_QSCALE
#define AV_CODEC_FLAG_QSCALE
Use fixed qscale.
Definition: avcodec.h:252
ff_af_queue_init
av_cold void ff_af_queue_init(AVCodecContext *avctx, AudioFrameQueue *afq)
Initialize AudioFrameQueue.
Definition: audio_frame_queue.c:28
vorbis_class
static const AVClass vorbis_class
Definition: libvorbisenc.c:66
av_get_channel_layout_string
void av_get_channel_layout_string(char *buf, int buf_size, int nb_channels, uint64_t channel_layout)
Return a description of a channel layout.
Definition: channel_layout.c:217
AVFrame
This structure describes decoded (raw) audio or video data.
Definition: frame.h:303
ff_libvorbis_encoder
const AVCodec ff_libvorbis_encoder
Definition: libvorbisenc.c:376
internal.h
AVPacket::data
uint8_t * data
Definition: packet.h:365
AVOption
AVOption.
Definition: opt.h:248
libvorbis_setup
static av_cold int libvorbis_setup(vorbis_info *vi, AVCodecContext *avctx)
Definition: libvorbisenc.c:94
LIBVORBIS_FRAME_SIZE
#define LIBVORBIS_FRAME_SIZE
Definition: libvorbisenc.c:38
av_vorbis_parse_frame
int av_vorbis_parse_frame(AVVorbisParseContext *s, const uint8_t *buf, int buf_size)
Get the duration for a Vorbis packet.
Definition: vorbis_parser.c:264
AVPacket::duration
int64_t duration
Duration of this packet in AVStream->time_base units, 0 if unknown.
Definition: packet.h:383
av_fifo_generic_read
int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void(*func)(void *, void *, int))
Feed data from an AVFifoBuffer to a user-supplied callback.
Definition: fifo.c:213
AVERROR_UNKNOWN
#define AVERROR_UNKNOWN
Unknown error, typically from an external library.
Definition: error.h:71
av_malloc
#define av_malloc(s)
Definition: tableprint_vlc.h:31
AVFifoBuffer
Definition: fifo.h:31
fifo.h
audio_frame_queue.h
AVCodecContext::initial_padding
int initial_padding
Audio only.
Definition: avcodec.h:1807
options
static const AVOption options[]
Definition: libvorbisenc.c:56
AVCodecContext::flags
int flags
AV_CODEC_FLAG_*.
Definition: avcodec.h:581
ff_af_queue_add
int ff_af_queue_add(AudioFrameQueue *afq, const AVFrame *f)
Add a frame to the queue.
Definition: audio_frame_queue.c:44
ogg_packet
static int ogg_packet(AVFormatContext *s, int *sid, int *dstart, int *dsize, int64_t *fpos)
find the next Ogg packet
Definition: oggdec.c:498
AV_CH_LAYOUT_STEREO
#define AV_CH_LAYOUT_STEREO
Definition: channel_layout.h:91
LibvorbisEncContext::av_class
AVClass * av_class
class for AVOptions
Definition: libvorbisenc.c:43
LibvorbisEncContext::vi
vorbis_info vi
vorbis_info used during init
Definition: libvorbisenc.c:44
AV_CH_LAYOUT_QUAD
#define AV_CH_LAYOUT_QUAD
Definition: channel_layout.h:99
libvorbis_encode_frame
static int libvorbis_encode_frame(AVCodecContext *avctx, AVPacket *avpkt, const AVFrame *frame, int *got_packet_ptr)
Definition: libvorbisenc.c:284
avassert.h
ff_samples_to_time_base
static av_always_inline int64_t ff_samples_to_time_base(AVCodecContext *avctx, int64_t samples)
Rescale from sample rate to AVCodecContext.time_base.
Definition: internal.h:262
AV_LOG_ERROR
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:181
av_fifo_space
int av_fifo_space(const AVFifoBuffer *f)
Return the amount of space in bytes in the AVFifoBuffer, that is the amount of data you can write int...
Definition: fifo.c:82
av_cold
#define av_cold
Definition: attributes.h:90
duration
int64_t duration
Definition: movenc.c:64
AVCodecContext::extradata_size
int extradata_size
Definition: avcodec.h:603
s
#define s(width, name)
Definition: cbs_vp9.c:257
AVCodecContext::global_quality
int global_quality
Global quality for codecs which cannot change it per frame.
Definition: avcodec.h:567
AV_OPT_FLAG_ENCODING_PARAM
#define AV_OPT_FLAG_ENCODING_PARAM
a generic parameter which can be set by the user for muxing or encoding
Definition: opt.h:278
libvorbis_encode_close
static av_cold int libvorbis_encode_close(AVCodecContext *avctx)
Definition: libvorbisenc.c:185
AV_OPT_TYPE_DOUBLE
@ AV_OPT_TYPE_DOUBLE
Definition: opt.h:227
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition: avutil.h:202
op
static int op(uint8_t **dst, const uint8_t *dst_end, GetByteContext *gb, int pixel, int count, int *x, int width, int linesize)
Perform decode operation.
Definition: anm.c:75
av_assert0
#define av_assert0(cond)
assert() equivalent, that is always enabled.
Definition: avassert.h:37
AudioFrameQueue
Definition: audio_frame_queue.h:32
channels
channels
Definition: aptx.h:33
AVCodecContext::rc_max_rate
int64_t rc_max_rate
maximum bitrate
Definition: avcodec.h:1300
AV_OPT_FLAG_AUDIO_PARAM
#define AV_OPT_FLAG_AUDIO_PARAM
Definition: opt.h:280
AVCodecDefault
Definition: internal.h:207
LIBAVUTIL_VERSION_INT
#define LIBAVUTIL_VERSION_INT
Definition: version.h:85
AVClass
Describe the class of an AVClass context structure.
Definition: log.h:67
NULL
#define NULL
Definition: coverity.c:32
AVCodecContext::bit_rate
int64_t bit_rate
the average bitrate
Definition: avcodec.h:551
av_default_item_name
const char * av_default_item_name(void *ptr)
Return the context name.
Definition: log.c:235
AV_CH_LAYOUT_5POINT1
#define AV_CH_LAYOUT_5POINT1
Definition: channel_layout.h:101
vorbis_parser.h
AV_CH_FRONT_CENTER
#define AV_CH_FRONT_CENTER
Definition: channel_layout.h:51
LibvorbisEncContext::afq
AudioFrameQueue afq
frame queue for timestamps
Definition: libvorbisenc.c:53
c
Undefined Behavior In the C some operations are like signed integer dereferencing freed accessing outside allocated Undefined Behavior must not occur in a C it is not safe even if the output of undefined operations is unused The unsafety may seem nit picking but Optimizing compilers have in fact optimized code on the assumption that no undefined Behavior occurs Optimizing code based on wrong assumptions can and has in some cases lead to effects beyond the output of computations The signed integer overflow problem in speed critical code Code which is highly optimized and works with signed integers sometimes has the problem that often the output of the computation does not c
Definition: undefined.txt:32
AVPacket::size
int size
Definition: packet.h:366
NULL_IF_CONFIG_SMALL
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification.
Definition: internal.h:117
AV_SAMPLE_FMT_NONE
@ AV_SAMPLE_FMT_NONE
Definition: samplefmt.h:59
AV_NOPTS_VALUE
#define AV_NOPTS_VALUE
Undefined timestamp value.
Definition: avutil.h:248
LibvorbisEncContext::vb
vorbis_block vb
vorbis_block used for analysis
Definition: libvorbisenc.c:46
LibvorbisEncContext::vp
AVVorbisParseContext * vp
parse context to get durations
Definition: libvorbisenc.c:52
header
static const uint8_t header[24]
Definition: sdr2.c:67
BUFFER_SIZE
#define BUFFER_SIZE
Definition: libvorbisenc.c:40
LibvorbisEncContext
Definition: libvorbisenc.c:42
xiph_len
static int xiph_len(int l)
Definition: libvorbisenc.c:180
AV_CH_LAYOUT_5POINT1_BACK
#define AV_CH_LAYOUT_5POINT1_BACK
Definition: channel_layout.h:103
offset
it s the only field you need to keep assuming you have a context There is some magic you don t need to care about around this just let it vf offset
Definition: writing_filters.txt:86
vorbis_error_to_averror
static int vorbis_error_to_averror(int ov_err)
Definition: libvorbisenc.c:84
AVCodecContext::channels
int channels
number of audio channels
Definition: avcodec.h:1099
AV_CH_LAYOUT_5POINT0
#define AV_CH_LAYOUT_5POINT0
Definition: channel_layout.h:100
AVPacket::pts
int64_t pts
Presentation timestamp in AVStream->time_base units; the time at which the decompressed packet will b...
Definition: packet.h:358
vorbis.h
AVCodecContext::extradata
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:602
AVCodecContext::cutoff
int cutoff
Audio cutoff bandwidth (0 means "automatic")
Definition: avcodec.h:1142
vorbis_encoding_channel_layout_offsets
static const uint8_t vorbis_encoding_channel_layout_offsets[8][8]
Definition: libvorbisenc.c:73
AVSampleFormat
AVSampleFormat
Audio sample formats.
Definition: samplefmt.h:58
AV_CH_LAYOUT_7POINT1
#define AV_CH_LAYOUT_7POINT1
Definition: channel_layout.h:112
AV_CH_BACK_CENTER
#define AV_CH_BACK_CENTER
Definition: channel_layout.h:57
AVCodec::name
const char * name
Name of the codec implementation.
Definition: codec.h:204
avcodec.h
ret
ret
Definition: filter_design.txt:187
AVClass::class_name
const char * class_name
The name of the class; usually it is the same name as the context structure type to which the AVClass...
Definition: log.h:72
frame
these buffered frames must be flushed immediately if a new input produces new the filter must not call request_frame to get more It must just process the frame or queue it The task of requesting more frames is left to the filter s request_frame method or the application If a filter has several the filter must be ready for frames arriving randomly on any input any filter with several inputs will most likely require some kind of queuing mechanism It is perfectly acceptable to have a limited queue and to drop frames when the inputs are too unbalanced request_frame For filters that do not use the this method is called when a frame is wanted on an output For a it should directly call filter_frame on the corresponding output For a if there are queued frames already one of these frames should be pushed If the filter should request a frame on one of its repeatedly until at least one frame has been pushed Return or at least make progress towards producing a frame
Definition: filter_design.txt:264
av_vorbis_parse_init
AVVorbisParseContext * av_vorbis_parse_init(const uint8_t *extradata, int extradata_size)
Allocate and initialize the Vorbis parser using headers in the extradata.
Definition: vorbis_parser.c:281
LibvorbisEncContext::eof
int eof
end-of-file flag
Definition: libvorbisenc.c:48
libvorbis_encode_init
static av_cold int libvorbis_encode_init(AVCodecContext *avctx)
Definition: libvorbisenc.c:205
AV_INPUT_BUFFER_PADDING_SIZE
#define AV_INPUT_BUFFER_PADDING_SIZE
Definition: avcodec.h:192
AVCodecContext
main external API structure.
Definition: avcodec.h:501
LibvorbisEncContext::iblock
double iblock
impulse block bias option
Definition: libvorbisenc.c:51
buffer
the frame and frame reference mechanism is intended to as much as expensive copies of that data while still allowing the filters to produce correct results The data is stored in buffers represented by AVFrame structures Several references can point to the same frame buffer
Definition: filter_design.txt:49
AV_CODEC_CAP_DELAY
#define AV_CODEC_CAP_DELAY
Encoder or decoder requires flushing with NULL input at the end in order to give the complete and cor...
Definition: codec.h:77
samples
Filter the word “frame” indicates either a video frame or a group of audio samples
Definition: filter_design.txt:8
LibvorbisEncContext::dsp_initialized
int dsp_initialized
vd has been initialized
Definition: libvorbisenc.c:49
AV_CODEC_FLAG_BITEXACT
#define AV_CODEC_FLAG_BITEXACT
Use only bitexact stuff (except (I)DCT).
Definition: avcodec.h:310
av_fifo_size
int av_fifo_size(const AVFifoBuffer *f)
Return the amount of data in bytes in the AVFifoBuffer, that is the amount of data you can read from ...
Definition: fifo.c:77
av_fifo_freep
void av_fifo_freep(AVFifoBuffer **f)
Free an AVFifoBuffer and reset pointer to NULL.
Definition: fifo.c:63
AVPacket
This structure stores compressed data.
Definition: packet.h:342
AVCodecContext::priv_data
void * priv_data
Definition: avcodec.h:528
av_fifo_alloc
AVFifoBuffer * av_fifo_alloc(unsigned int size)
Initialize an AVFifoBuffer.
Definition: fifo.c:43
AVERROR_BUG
#define AVERROR_BUG
Internal bug, also see AVERROR_BUG2.
Definition: error.h:50
av_log
#define av_log(a,...)
Definition: tableprint_vlc.h:28
AV_CODEC_ID_VORBIS
@ AV_CODEC_ID_VORBIS
Definition: codec_id.h:426
FF_QP2LAMBDA
#define FF_QP2LAMBDA
factor to convert from H.263 QP to lambda
Definition: avutil.h:227
LibvorbisEncContext::pkt_fifo
AVFifoBuffer * pkt_fifo
output packet buffer
Definition: libvorbisenc.c:47
AV_CODEC_CAP_SMALL_LAST_FRAME
#define AV_CODEC_CAP_SMALL_LAST_FRAME
Codec can be fed a final frame with a smaller size.
Definition: codec.h:82
ff_alloc_packet2
int ff_alloc_packet2(AVCodecContext *avctx, AVPacket *avpkt, int64_t size, int64_t min_size)
Check AVPacket size and/or allocate data.
Definition: encode.c:33
LibvorbisEncContext::vd
vorbis_dsp_state vd
DSP state used for analysis
Definition: libvorbisenc.c:45
AV_CH_LAYOUT_2_2
#define AV_CH_LAYOUT_2_2
Definition: channel_layout.h:98