FFmpeg
libvorbisdec.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 "avcodec.h"
24 #include "bytestream.h"
25 #include "internal.h"
26 
27 typedef struct OggVorbisDecContext {
28  vorbis_info vi; /**< vorbis_info used during init */
29  vorbis_dsp_state vd; /**< DSP state used for analysis */
30  vorbis_block vb; /**< vorbis_block used for analysis */
31  vorbis_comment vc; /**< VorbisComment info */
32  ogg_packet op; /**< ogg packet */
34 
35 static int oggvorbis_decode_close(AVCodecContext *avccontext);
36 
37 static int oggvorbis_decode_init(AVCodecContext *avccontext) {
38  OggVorbisDecContext *context = avccontext->priv_data ;
39  uint8_t *p= avccontext->extradata;
40  int i, hsizes[3], ret;
41  unsigned char *headers[3], *extradata = avccontext->extradata;
42 
43  if(! avccontext->extradata_size || ! p) {
44  av_log(avccontext, AV_LOG_ERROR, "vorbis extradata absent\n");
45  return AVERROR(EINVAL);
46  }
47 
48  vorbis_info_init(&context->vi) ;
49  vorbis_comment_init(&context->vc) ;
50 
51  if(p[0] == 0 && p[1] == 30) {
52  int sizesum = 0;
53  for(i = 0; i < 3; i++){
54  hsizes[i] = bytestream_get_be16((const uint8_t **)&p);
55  sizesum += 2 + hsizes[i];
56  if (sizesum > avccontext->extradata_size) {
57  av_log(avccontext, AV_LOG_ERROR, "vorbis extradata too small\n");
58  ret = AVERROR_INVALIDDATA;
59  goto error;
60  }
61 
62  headers[i] = p;
63  p += hsizes[i];
64  }
65  } else if(*p == 2) {
66  unsigned int offset = 1;
67  unsigned int sizesum = 1;
68  p++;
69  for(i=0; i<2; i++) {
70  hsizes[i] = 0;
71  while((*p == 0xFF) && (sizesum < avccontext->extradata_size)) {
72  hsizes[i] += 0xFF;
73  offset++;
74  sizesum += 1 + 0xFF;
75  p++;
76  }
77  hsizes[i] += *p;
78  offset++;
79  sizesum += 1 + *p;
80  if(sizesum > avccontext->extradata_size) {
81  av_log(avccontext, AV_LOG_ERROR,
82  "vorbis header sizes damaged\n");
83  ret = AVERROR_INVALIDDATA;
84  goto error;
85  }
86  p++;
87  }
88  hsizes[2] = avccontext->extradata_size - hsizes[0]-hsizes[1]-offset;
89 #if 0
90  av_log(avccontext, AV_LOG_DEBUG,
91  "vorbis header sizes: %d, %d, %d, / extradata_len is %d \n",
92  hsizes[0], hsizes[1], hsizes[2], avccontext->extradata_size);
93 #endif
94  headers[0] = extradata + offset;
95  headers[1] = extradata + offset + hsizes[0];
96  headers[2] = extradata + offset + hsizes[0] + hsizes[1];
97  } else {
98  av_log(avccontext, AV_LOG_ERROR,
99  "vorbis initial header len is wrong: %d\n", *p);
100  ret = AVERROR_INVALIDDATA;
101  goto error;
102  }
103 
104  for(i=0; i<3; i++){
105  context->op.b_o_s= i==0;
106  context->op.bytes = hsizes[i];
107  context->op.packet = headers[i];
108  if(vorbis_synthesis_headerin(&context->vi, &context->vc, &context->op)<0){
109  av_log(avccontext, AV_LOG_ERROR, "%d. vorbis header damaged\n", i+1);
110  ret = AVERROR_INVALIDDATA;
111  goto error;
112  }
113  }
114 
115  avccontext->channels = context->vi.channels;
116  avccontext->sample_rate = context->vi.rate;
117  avccontext->sample_fmt = AV_SAMPLE_FMT_S16;
118  avccontext->time_base= (AVRational){1, avccontext->sample_rate};
119 
120  vorbis_synthesis_init(&context->vd, &context->vi);
121  vorbis_block_init(&context->vd, &context->vb);
122 
123  return 0 ;
124 
125  error:
126  oggvorbis_decode_close(avccontext);
127  return ret;
128 }
129 
130 
131 static inline int conv(int samples, float **pcm, char *buf, int channels) {
132  int i, j;
133  ogg_int16_t *ptr, *data = (ogg_int16_t*)buf ;
134  float *mono ;
135 
136  for(i = 0 ; i < channels ; i++){
137  ptr = &data[i];
138  mono = pcm[i] ;
139 
140  for(j = 0 ; j < samples ; j++) {
141  *ptr = av_clip_int16(mono[j] * 32767.f);
142  ptr += channels;
143  }
144  }
145 
146  return 0 ;
147 }
148 
149 static int oggvorbis_decode_frame(AVCodecContext *avccontext, void *data,
150  int *got_frame_ptr, AVPacket *avpkt)
151 {
152  OggVorbisDecContext *context = avccontext->priv_data ;
153  AVFrame *frame = data;
154  float **pcm ;
155  ogg_packet *op= &context->op;
156  int samples, total_samples, total_bytes;
157  int ret;
158  int16_t *output;
159 
160  if(!avpkt->size){
161  //FIXME flush
162  return 0;
163  }
164 
165  frame->nb_samples = 8192*4;
166  if ((ret = ff_get_buffer(avccontext, frame, 0)) < 0)
167  return ret;
168  output = (int16_t *)frame->data[0];
169 
170 
171  op->packet = avpkt->data;
172  op->bytes = avpkt->size;
173 
174 // av_log(avccontext, AV_LOG_DEBUG, "%d %d %d %"PRId64" %"PRId64" %d %d\n", op->bytes, op->b_o_s, op->e_o_s, op->granulepos, op->packetno, buf_size, context->vi.rate);
175 
176 /* for(i=0; i<op->bytes; i++)
177  av_log(avccontext, AV_LOG_DEBUG, "%02X ", op->packet[i]);
178  av_log(avccontext, AV_LOG_DEBUG, "\n");*/
179 
180  if(vorbis_synthesis(&context->vb, op) == 0)
181  vorbis_synthesis_blockin(&context->vd, &context->vb) ;
182 
183  total_samples = 0 ;
184  total_bytes = 0 ;
185 
186  while((samples = vorbis_synthesis_pcmout(&context->vd, &pcm)) > 0) {
187  conv(samples, pcm, (char*)output + total_bytes, context->vi.channels) ;
188  total_bytes += samples * 2 * context->vi.channels ;
189  total_samples += samples ;
190  vorbis_synthesis_read(&context->vd, samples) ;
191  }
192 
193  frame->nb_samples = total_samples;
194  *got_frame_ptr = total_samples > 0;
195  return avpkt->size;
196 }
197 
198 
199 static int oggvorbis_decode_close(AVCodecContext *avccontext) {
200  OggVorbisDecContext *context = avccontext->priv_data ;
201 
202  vorbis_block_clear(&context->vb);
203  vorbis_dsp_clear(&context->vd);
204  vorbis_info_clear(&context->vi) ;
205  vorbis_comment_clear(&context->vc) ;
206 
207  return 0 ;
208 }
209 
210 
212  .name = "libvorbis",
213  .long_name = NULL_IF_CONFIG_SMALL("libvorbis"),
214  .type = AVMEDIA_TYPE_AUDIO,
215  .id = AV_CODEC_ID_VORBIS,
216  .priv_data_size = sizeof(OggVorbisDecContext),
219  .close = oggvorbis_decode_close,
220  .capabilities = AV_CODEC_CAP_DELAY,
221 };
#define AVERROR_INVALIDDATA
Invalid data found when processing input.
Definition: error.h:59
This structure describes decoded (raw) audio or video data.
Definition: frame.h:295
ogg_packet op
ogg packet
Definition: libvorbisdec.c:32
ptrdiff_t const GLvoid * data
Definition: opengl_enc.c:100
static int conv(int samples, float **pcm, char *buf, int channels)
Definition: libvorbisdec.c:131
static av_cold int init(AVCodecContext *avctx)
Definition: avrndec.c:35
vorbis_dsp_state vd
DSP state used for analysis.
Definition: libvorbisdec.c:29
channels
Definition: aptx.c:30
int size
Definition: avcodec.h:1481
AVCodec.
Definition: avcodec.h:3492
static void decode(AVCodecContext *dec_ctx, AVPacket *pkt, AVFrame *frame, FILE *outfile)
Definition: decode_audio.c:71
AVRational time_base
This is the fundamental unit of time (in seconds) in terms of which frame timestamps are represented...
Definition: avcodec.h:1691
#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: avcodec.h:1009
vorbis_block vb
vorbis_block used for analysis
Definition: libvorbisdec.c:30
enum AVSampleFormat sample_fmt
audio sample format
Definition: avcodec.h:2236
uint8_t
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
#define f(width, name)
Definition: cbs_vp9.c:255
static int oggvorbis_decode_init(AVCodecContext *avccontext)
Definition: libvorbisdec.c:37
filter_frame For filters that do not use the this method is called when a frame is pushed to the filter s input It can be called at any time except in a reentrant way If the input frame is enough to produce output
uint8_t * extradata
some codecs need / can use extradata like Huffman tables.
Definition: avcodec.h:1669
uint8_t * data
Definition: avcodec.h:1480
#define av_log(a,...)
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:259
#define AV_LOG_ERROR
Something went wrong and cannot losslessly be recovered.
Definition: log.h:176
vorbis_comment vc
VorbisComment info.
Definition: libvorbisdec.c:31
#define NULL_IF_CONFIG_SMALL(x)
Return NULL if CONFIG_SMALL is true, otherwise the argument without modification. ...
Definition: internal.h:186
#define AV_LOG_DEBUG
Stuff which is only useful for libav* developers.
Definition: log.h:197
const char * name
Name of the codec implementation.
Definition: avcodec.h:3499
vorbis_info vi
vorbis_info used during init
Definition: libvorbisdec.c:28
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
static void error(const char *err)
Libavcodec external API header.
static int oggvorbis_decode_frame(AVCodecContext *avccontext, void *data, int *got_frame_ptr, AVPacket *avpkt)
Definition: libvorbisdec.c:149
int sample_rate
samples per second
Definition: avcodec.h:2228
static int ogg_packet(AVFormatContext *s, int *sid, int *dstart, int *dsize, int64_t *fpos)
find the next Ogg packet
Definition: oggdec.c:477
main external API structure.
Definition: avcodec.h:1568
int ff_get_buffer(AVCodecContext *avctx, AVFrame *frame, int flags)
Get a buffer for a frame.
Definition: decode.c:1968
static int oggvorbis_decode_close(AVCodecContext *avccontext)
Definition: libvorbisdec.c:199
void * buf
Definition: avisynth_c.h:766
int extradata_size
Definition: avcodec.h:1670
Rational number (pair of numerator and denominator).
Definition: rational.h:58
uint8_t * data[AV_NUM_DATA_POINTERS]
pointer to the picture/channel planes.
Definition: frame.h:309
common internal api header.
signed 16 bits
Definition: samplefmt.h:61
AVCodec ff_libvorbis_decoder
Definition: libvorbisdec.c:211
void * priv_data
Definition: avcodec.h:1595
int channels
number of audio channels
Definition: avcodec.h:2229
Filter the word “frame” indicates either a video frame or a group of audio samples
FFmpeg currently uses a custom build this text attempts to document some of its obscure features and options Makefile the full command issued by make and its output will be shown on the screen DBG Preprocess x86 external assembler files to a dbg asm file in the object which then gets compiled Helps in developing those assembler files DESTDIR Destination directory for the install useful to prepare packages or install FFmpeg in cross environments GEN Set to ‘1’ to generate the missing or mismatched references Makefile builds all the libraries and the executables fate Run the fate test note that you must have installed it fate list List all fate regression test targets install Install headers
Definition: build_system.txt:1
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
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 keep it simple and lowercase description are in without and describe what they for example set the foo of the bar offset is the offset of the field in your local context
This structure stores compressed data.
Definition: avcodec.h:1457
int nb_samples
number of audio samples (per channel) described by this frame
Definition: frame.h:361