libavformat/ogg.c

   1 /*
   2  * Ogg bitstream support
   3  * Mark Hills <mark@pogo.org.uk>
   4  *
   5  * Uses libogg, but requires libvorbisenc to construct correct headers
   6  * when containing Vorbis stream -- currently the only format supported
   7  */
   8
   9 #include <stdio.h>
  10
  11 #include <ogg/ogg.h>
  12
  13 #include "avformat.h"
  14
  15 #undef NDEBUG
  16 #include <assert.h>
  17
  18 #define DECODER_BUFFER_SIZE 4096
  19
  20
  21 typedef struct OggContext {
  22     /* output */
  23     ogg_stream_state os ;
  24     int header_handled ;
  25     ogg_packet op;
  26
  27     /* input */
  28     ogg_sync_state oy ;
  29 } OggContext ;
  30
  31
  32 #ifdef CONFIG_MUXERS
  33 static int ogg_write_header(AVFormatContext *avfcontext)
  34 {
  35     OggContext *context = avfcontext->priv_data;
  36     ogg_packet *op= &context->op;
  37     int n;
  38
  39     ogg_stream_init(&context->os, 31415);
  40
  41     for(n = 0 ; n < avfcontext->nb_streams ; n++) {
  42         AVCodecContext *codec = avfcontext->streams[n]->codec;
  43         uint8_t *headers = codec->extradata;
  44         int headers_len = codec->extradata_size;
  45         uint8_t *header_start[3];
  46         int header_len[3];
  47         int i, j;
  48
  49         av_set_pts_info(avfcontext->streams[n], 60, 1, AV_TIME_BASE);
  50
  51         for(j=1,i=0;i<2;++i, ++j) {
  52             header_len[i]=0;
  53             while(j<headers_len && headers[j]==0xff) {
  54                 header_len[i]+=0xff;
  55                 ++j;
  56             }
  57             header_len[i]+=headers[j];
  58         }
  59         header_len[2]=headers_len-header_len[0]-header_len[1]-j;
  60         headers+=j;
  61         header_start[0] = headers;
  62         header_start[1] = header_start[0] + header_len[0];
  63         header_start[2] = header_start[1] + header_len[1];
  64
  65         for(i=0; i < 3; ++i){
  66             op->bytes = header_len[i];
  67
  68             op->packet= header_start[i];
  69             op->b_o_s= op->packetno==0;
  70
  71             ogg_stream_packetin(&context->os, op);
  72
  73             op->packetno++; //FIXME multiple streams
  74         }
  75
  76         context->header_handled = 0 ;
  77     }
  78
  79     return 0 ;
  80 }
  81
  82 static int ogg_write_packet(AVFormatContext *avfcontext, AVPacket *pkt)
  83 {
  84     OggContext *context = avfcontext->priv_data ;
  85     AVCodecContext *avctx= avfcontext->streams[pkt->stream_index]->codec;
  86     ogg_packet *op= &context->op;
  87     ogg_page og ;
  88     int64_t pts;
  89
  90     pts= av_rescale(pkt->pts, avctx->sample_rate, AV_TIME_BASE);
  91
  92 //    av_log(avfcontext, AV_LOG_DEBUG, "M%d\n", size);
  93
  94     /* flush header packets so audio starts on a new page */
  95
  96     if(!context->header_handled) {
  97         while(ogg_stream_flush(&context->os, &og)) {
  98             put_buffer(&avfcontext->pb, og.header, og.header_len) ;
  99             put_buffer(&avfcontext->pb, og.body, og.body_len) ;
 100             put_flush_packet(&avfcontext->pb);
 101         }
 102         context->header_handled = 1 ;
 103     }
 104
 105     op->packet = (uint8_t*) pkt->data;
 106     op->bytes  = pkt->size;
 107     op->b_o_s  = op->packetno == 0;
 108     op->granulepos= pts;
 109
 110     /* correct the fields in the packet -- essential for streaming */
 111
 112     ogg_stream_packetin(&context->os, op);
 113
 114     while(ogg_stream_pageout(&context->os, &og)) {
 115         put_buffer(&avfcontext->pb, og.header, og.header_len);
 116         put_buffer(&avfcontext->pb, og.body, og.body_len);
 117         put_flush_packet(&avfcontext->pb);
 118     }
 119     op->packetno++;
 120
 121     return 0;
 122 }
 123
 124
 125 static int ogg_write_trailer(AVFormatContext *avfcontext) {
 126     OggContext *context = avfcontext->priv_data ;
 127     ogg_page og ;
 128
 129     while(ogg_stream_flush(&context->os, &og)) {
 130         put_buffer(&avfcontext->pb, og.header, og.header_len) ;
 131         put_buffer(&avfcontext->pb, og.body, og.body_len) ;
 132         put_flush_packet(&avfcontext->pb);
 133     }
 134
 135     ogg_stream_clear(&context->os) ;
 136     return 0 ;
 137 }
 138
 139
 140 AVOutputFormat ogg_muxer = {
 141     "ogg",
 142     "Ogg Vorbis",
 143     "audio/x-vorbis",
 144     "ogg",
 145     sizeof(OggContext),
 146     CODEC_ID_VORBIS,
 147     0,
 148     ogg_write_header,
 149     ogg_write_packet,
 150     ogg_write_trailer,
 151 } ;
 152 #endif //CONFIG_MUXERS
 153
 154 #if 0
 155 static int next_packet(AVFormatContext *avfcontext, ogg_packet *op) {
 156     OggContext *context = avfcontext->priv_data ;
 157     ogg_page og ;
 158     char *buf ;
 159
 160     while(ogg_stream_packetout(&context->os, op) != 1) {
 161
 162         /* while no pages are available, read in more data to the sync */
 163         while(ogg_sync_pageout(&context->oy, &og) != 1) {
 164             buf = ogg_sync_buffer(&context->oy, DECODER_BUFFER_SIZE) ;
 165             if(get_buffer(&avfcontext->pb, buf, DECODER_BUFFER_SIZE) <= 0)
 166                 return 1 ;
 167             ogg_sync_wrote(&context->oy, DECODER_BUFFER_SIZE) ;
 168         }
 169
 170         /* got a page. Feed it into the stream and get the packet */
 171         if(ogg_stream_pagein(&context->os, &og) != 0)
 172             return 1 ;
 173     }
 174
 175     return 0 ;
 176 }
 177
 178
 179 static int ogg_read_header(AVFormatContext *avfcontext, AVFormatParameters *ap)
 180 {
 181     OggContext *context = avfcontext->priv_data;
 182     ogg_packet op ;
 183     char *buf ;
 184     ogg_page og ;
 185     AVStream *ast ;
 186     AVCodecContext *codec;
 187     uint8_t *p;
 188     int i;
 189
 190     ogg_sync_init(&context->oy) ;
 191     buf = ogg_sync_buffer(&context->oy, DECODER_BUFFER_SIZE) ;
 192
 193     if(get_buffer(&avfcontext->pb, buf, DECODER_BUFFER_SIZE) <= 0)
 194         return AVERROR_IO ;
 195
 196     ogg_sync_wrote(&context->oy, DECODER_BUFFER_SIZE) ;
 197     ogg_sync_pageout(&context->oy, &og) ;
 198     ogg_stream_init(&context->os, ogg_page_serialno(&og)) ;
 199     ogg_stream_pagein(&context->os, &og) ;
 200
 201     /* currently only one vorbis stream supported */
 202
 203     ast = av_new_stream(avfcontext, 0) ;
 204     if(!ast)
 205         return AVERROR_NOMEM ;
 206     av_set_pts_info(ast, 60, 1, AV_TIME_BASE);
 207
 208     codec= &ast->codec;
 209     codec->codec_type = CODEC_TYPE_AUDIO;
 210     codec->codec_id = CODEC_ID_VORBIS;
 211     for(i=0; i<3; i++){
 212         if(next_packet(avfcontext, &op)){
 213             return -1;
 214         }
 215         if(op.bytes >= (1<<16) || op.bytes < 0)
 216             return -1;
 217         codec->extradata_size+= 2 + op.bytes;
 218         codec->extradata= av_realloc(codec->extradata, codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
 219         memset(codec->extradata + codec->extradata_size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
 220         p= codec->extradata + codec->extradata_size - 2 - op.bytes;
 221         *(p++)= op.bytes>>8;
 222         *(p++)= op.bytes&0xFF;
 223         memcpy(p, op.packet, op.bytes);
 224     }
 225
 226     return 0 ;
 227 }
 228
 229
 230 static int ogg_read_packet(AVFormatContext *avfcontext, AVPacket *pkt) {
 231     ogg_packet op ;
 232
 233     if(next_packet(avfcontext, &op))
 234         return AVERROR_IO ;
 235     if(av_new_packet(pkt, op.bytes) < 0)
 236         return AVERROR_IO ;
 237     pkt->stream_index = 0 ;
 238     memcpy(pkt->data, op.packet, op.bytes);
 239     if(avfcontext->streams[0]->codec.sample_rate && op.granulepos!=-1)
 240         pkt->pts= av_rescale(op.granulepos, AV_TIME_BASE, avfcontext->streams[0]->codec.sample_rate);
 241 //    printf("%lld %d %d\n", pkt->pts, (int)op.granulepos, avfcontext->streams[0]->codec.sample_rate);
 242
 243     return op.bytes;
 244 }
 245
 246
 247 static int ogg_read_close(AVFormatContext *avfcontext) {
 248     OggContext *context = avfcontext->priv_data ;
 249
 250     ogg_stream_clear(&context->os) ;
 251     ogg_sync_clear(&context->oy) ;
 252
 253     return 0 ;
 254 }
 255
 256
 257 static AVInputFormat ogg_iformat = {
 258     "ogg",
 259     "Ogg Vorbis",
 260     sizeof(OggContext),
 261     NULL,
 262     ogg_read_header,
 263     ogg_read_packet,
 264     ogg_read_close,
 265     .extensions = "ogg",
 266 } ;
 267 #endif