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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_init(AVCodecContext *avccontext) {
36  OggVorbisDecContext *context = avccontext->priv_data ;
37  uint8_t *p= avccontext->extradata;
38  int i, hsizes[3];
39  unsigned char *headers[3], *extradata = avccontext->extradata;
40 
41  vorbis_info_init(&context->vi) ;
42  vorbis_comment_init(&context->vc) ;
43 
44  if(! avccontext->extradata_size || ! p) {
45  av_log(avccontext, AV_LOG_ERROR, "vorbis extradata absent\n");
46  return -1;
47  }
48 
49  if(p[0] == 0 && p[1] == 30) {
50  for(i = 0; i < 3; i++){
51  hsizes[i] = bytestream_get_be16((const uint8_t **)&p);
52  headers[i] = p;
53  p += hsizes[i];
54  }
55  } else if(*p == 2) {
56  unsigned int offset = 1;
57  p++;
58  for(i=0; i<2; i++) {
59  hsizes[i] = 0;
60  while((*p == 0xFF) && (offset < avccontext->extradata_size)) {
61  hsizes[i] += 0xFF;
62  offset++;
63  p++;
64  }
65  if(offset >= avccontext->extradata_size - 1) {
66  av_log(avccontext, AV_LOG_ERROR,
67  "vorbis header sizes damaged\n");
68  return -1;
69  }
70  hsizes[i] += *p;
71  offset++;
72  p++;
73  }
74  hsizes[2] = avccontext->extradata_size - hsizes[0]-hsizes[1]-offset;
75 #if 0
76  av_log(avccontext, AV_LOG_DEBUG,
77  "vorbis header sizes: %d, %d, %d, / extradata_len is %d \n",
78  hsizes[0], hsizes[1], hsizes[2], avccontext->extradata_size);
79 #endif
80  headers[0] = extradata + offset;
81  headers[1] = extradata + offset + hsizes[0];
82  headers[2] = extradata + offset + hsizes[0] + hsizes[1];
83  } else {
84  av_log(avccontext, AV_LOG_ERROR,
85  "vorbis initial header len is wrong: %d\n", *p);
86  return -1;
87  }
88 
89  for(i=0; i<3; i++){
90  context->op.b_o_s= i==0;
91  context->op.bytes = hsizes[i];
92  context->op.packet = headers[i];
93  if(vorbis_synthesis_headerin(&context->vi, &context->vc, &context->op)<0){
94  av_log(avccontext, AV_LOG_ERROR, "%d. vorbis header damaged\n", i+1);
95  return -1;
96  }
97  }
98 
99  avccontext->channels = context->vi.channels;
100  avccontext->sample_rate = context->vi.rate;
101  avccontext->sample_fmt = AV_SAMPLE_FMT_S16;
102  avccontext->time_base= (AVRational){1, avccontext->sample_rate};
103 
104  vorbis_synthesis_init(&context->vd, &context->vi);
105  vorbis_block_init(&context->vd, &context->vb);
106 
107  return 0 ;
108 }
109 
110 
111 static inline int conv(int samples, float **pcm, char *buf, int channels) {
112  int i, j;
113  ogg_int16_t *ptr, *data = (ogg_int16_t*)buf ;
114  float *mono ;
115 
116  for(i = 0 ; i < channels ; i++){
117  ptr = &data[i];
118  mono = pcm[i] ;
119 
120  for(j = 0 ; j < samples ; j++) {
121  *ptr = av_clip_int16(mono[j] * 32767.f);
122  ptr += channels;
123  }
124  }
125 
126  return 0 ;
127 }
128 
129 static int oggvorbis_decode_frame(AVCodecContext *avccontext, void *data,
130  int *got_frame_ptr, AVPacket *avpkt)
131 {
132  OggVorbisDecContext *context = avccontext->priv_data ;
133  AVFrame *frame = data;
134  float **pcm ;
135  ogg_packet *op= &context->op;
136  int samples, total_samples, total_bytes;
137  int ret;
138  int16_t *output;
139 
140  if(!avpkt->size){
141  //FIXME flush
142  return 0;
143  }
144 
145  frame->nb_samples = 8192*4;
146  if ((ret = ff_get_buffer(avccontext, frame, 0)) < 0)
147  return ret;
148  output = (int16_t *)frame->data[0];
149 
150 
151  op->packet = avpkt->data;
152  op->bytes = avpkt->size;
153 
154 // 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);
155 
156 /* for(i=0; i<op->bytes; i++)
157  av_log(avccontext, AV_LOG_DEBUG, "%02X ", op->packet[i]);
158  av_log(avccontext, AV_LOG_DEBUG, "\n");*/
159 
160  if(vorbis_synthesis(&context->vb, op) == 0)
161  vorbis_synthesis_blockin(&context->vd, &context->vb) ;
162 
163  total_samples = 0 ;
164  total_bytes = 0 ;
165 
166  while((samples = vorbis_synthesis_pcmout(&context->vd, &pcm)) > 0) {
167  conv(samples, pcm, (char*)output + total_bytes, context->vi.channels) ;
168  total_bytes += samples * 2 * context->vi.channels ;
169  total_samples += samples ;
170  vorbis_synthesis_read(&context->vd, samples) ;
171  }
172 
173  frame->nb_samples = total_samples;
174  *got_frame_ptr = total_samples > 0;
175  return avpkt->size;
176 }
177 
178 
179 static int oggvorbis_decode_close(AVCodecContext *avccontext) {
180  OggVorbisDecContext *context = avccontext->priv_data ;
181 
182  vorbis_info_clear(&context->vi) ;
183  vorbis_comment_clear(&context->vc) ;
184 
185  return 0 ;
186 }
187 
188 
190  .name = "libvorbis",
191  .long_name = NULL_IF_CONFIG_SMALL("libvorbis"),
192  .type = AVMEDIA_TYPE_AUDIO,
193  .id = AV_CODEC_ID_VORBIS,
194  .priv_data_size = sizeof(OggVorbisDecContext),
198  .capabilities = CODEC_CAP_DELAY,
199 };