/* * Ogg bitstream support * Mark Hills * * Uses libogg, but requires libvorbisenc to construct correct headers * when containing Vorbis stream -- currently the only format supported */ #include #include #include "avformat.h" #undef NDEBUG #include #define DECODER_BUFFER_SIZE 4096 typedef struct OggContext { /* output */ ogg_stream_state os ; int header_handled ; ogg_packet op; /* input */ ogg_sync_state oy ; } OggContext ; #ifdef CONFIG_ENCODERS static int ogg_write_header(AVFormatContext *avfcontext) { OggContext *context = avfcontext->priv_data; ogg_packet *op= &context->op; int n, i; ogg_stream_init(&context->os, 31415); for(n = 0 ; n < avfcontext->nb_streams ; n++) { AVCodecContext *codec = &avfcontext->streams[n]->codec; uint8_t *p= codec->extradata; av_set_pts_info(avfcontext->streams[n], 60, 1, AV_TIME_BASE); for(i=0; i < codec->extradata_size; i+= op->bytes){ op->bytes = p[i++]<<8; op->bytes+= p[i++]; op->packet= &p[i]; op->b_o_s= op->packetno==0; ogg_stream_packetin(&context->os, op); op->packetno++; //FIXME multiple streams } context->header_handled = 0 ; } return 0 ; } static int ogg_write_packet(AVFormatContext *avfcontext, AVPacket *pkt) { OggContext *context = avfcontext->priv_data ; AVCodecContext *avctx= &avfcontext->streams[pkt->stream_index]->codec; ogg_packet *op= &context->op; ogg_page og ; int64_t pts; pts= av_rescale(pkt->pts, avctx->sample_rate, AV_TIME_BASE); // av_log(avfcontext, AV_LOG_DEBUG, "M%d\n", size); /* flush header packets so audio starts on a new page */ if(!context->header_handled) { while(ogg_stream_flush(&context->os, &og)) { put_buffer(&avfcontext->pb, og.header, og.header_len) ; put_buffer(&avfcontext->pb, og.body, og.body_len) ; put_flush_packet(&avfcontext->pb); } context->header_handled = 1 ; } op->packet = (uint8_t*) pkt->data; op->bytes = pkt->size; op->b_o_s = op->packetno == 0; op->granulepos= pts; /* correct the fields in the packet -- essential for streaming */ ogg_stream_packetin(&context->os, op); while(ogg_stream_pageout(&context->os, &og)) { put_buffer(&avfcontext->pb, og.header, og.header_len); put_buffer(&avfcontext->pb, og.body, og.body_len); put_flush_packet(&avfcontext->pb); } op->packetno++; return 0; } static int ogg_write_trailer(AVFormatContext *avfcontext) { OggContext *context = avfcontext->priv_data ; ogg_page og ; while(ogg_stream_flush(&context->os, &og)) { put_buffer(&avfcontext->pb, og.header, og.header_len) ; put_buffer(&avfcontext->pb, og.body, og.body_len) ; put_flush_packet(&avfcontext->pb); } ogg_stream_clear(&context->os) ; return 0 ; } static AVOutputFormat ogg_oformat = { "ogg", "Ogg Vorbis", "audio/x-vorbis", "ogg", sizeof(OggContext), CODEC_ID_VORBIS, 0, ogg_write_header, ogg_write_packet, ogg_write_trailer, } ; #endif //CONFIG_ENCODERS static int next_packet(AVFormatContext *avfcontext, ogg_packet *op) { OggContext *context = avfcontext->priv_data ; ogg_page og ; char *buf ; while(ogg_stream_packetout(&context->os, op) != 1) { /* while no pages are available, read in more data to the sync */ while(ogg_sync_pageout(&context->oy, &og) != 1) { buf = ogg_sync_buffer(&context->oy, DECODER_BUFFER_SIZE) ; if(get_buffer(&avfcontext->pb, buf, DECODER_BUFFER_SIZE) <= 0) return 1 ; ogg_sync_wrote(&context->oy, DECODER_BUFFER_SIZE) ; } /* got a page. Feed it into the stream and get the packet */ if(ogg_stream_pagein(&context->os, &og) != 0) return 1 ; } return 0 ; } static int ogg_read_header(AVFormatContext *avfcontext, AVFormatParameters *ap) { OggContext *context = avfcontext->priv_data; ogg_packet op ; char *buf ; ogg_page og ; AVStream *ast ; AVCodecContext *codec; uint8_t *p; int i; avfcontext->ctx_flags |= AVFMTCTX_NOHEADER; ogg_sync_init(&context->oy) ; buf = ogg_sync_buffer(&context->oy, DECODER_BUFFER_SIZE) ; if(get_buffer(&avfcontext->pb, buf, DECODER_BUFFER_SIZE) <= 0) return AVERROR_IO ; ogg_sync_wrote(&context->oy, DECODER_BUFFER_SIZE) ; ogg_sync_pageout(&context->oy, &og) ; ogg_stream_init(&context->os, ogg_page_serialno(&og)) ; ogg_stream_pagein(&context->os, &og) ; /* currently only one vorbis stream supported */ ast = av_new_stream(avfcontext, 0) ; if(!ast) return AVERROR_NOMEM ; av_set_pts_info(ast, 60, 1, AV_TIME_BASE); codec= &ast->codec; codec->codec_type = CODEC_TYPE_AUDIO; codec->codec_id = CODEC_ID_VORBIS; for(i=0; i<3; i++){ if(next_packet(avfcontext, &op)){ return -1; } codec->extradata_size+= 2 + op.bytes; codec->extradata= av_realloc(codec->extradata, codec->extradata_size); p= codec->extradata + codec->extradata_size - 2 - op.bytes; *(p++)= op.bytes>>8; *(p++)= op.bytes&0xFF; memcpy(p, op.packet, op.bytes); } return 0 ; } static int ogg_read_packet(AVFormatContext *avfcontext, AVPacket *pkt) { ogg_packet op ; if(next_packet(avfcontext, &op)) return AVERROR_IO ; if(av_new_packet(pkt, op.bytes) < 0) return AVERROR_IO ; pkt->stream_index = 0 ; memcpy(pkt->data, op.packet, op.bytes); if(avfcontext->streams[0]->codec.sample_rate && op.granulepos!=-1) pkt->pts= av_rescale(op.granulepos, AV_TIME_BASE, avfcontext->streams[0]->codec.sample_rate); // printf("%lld %d %d\n", pkt->pts, (int)op.granulepos, avfcontext->streams[0]->codec.sample_rate); return op.bytes; } static int ogg_read_close(AVFormatContext *avfcontext) { OggContext *context = avfcontext->priv_data ; ogg_stream_clear(&context->os) ; ogg_sync_clear(&context->oy) ; av_freep(&avfcontext->streams[0]->codec.extradata); return 0 ; } static AVInputFormat ogg_iformat = { "ogg", "Ogg Vorbis", sizeof(OggContext), NULL, ogg_read_header, ogg_read_packet, ogg_read_close, .extensions = "ogg", } ; int ogg_init(void) { #ifdef CONFIG_ENCODERS av_register_output_format(&ogg_oformat) ; #endif av_register_input_format(&ogg_iformat); return 0 ; }