--- /dev/null
+/*
+ * Ogg bitstream support
+ * Mark Hills <mark@pogo.org.uk>
+ *
+ * Uses libogg, but requires libvorbisenc to construct correct headers
+ * when containing Vorbis stream -- currently the only format supported
+ */
+
+#include <stdio.h>
+#include <time.h>
+
+#include <ogg/ogg.h>
+#include <vorbis/vorbisenc.h>
+
+#include "avformat.h"
+#include "oggvorbis.h"
+
+#define DECODER_BUFFER_SIZE 4096
+
+
+typedef struct OggContext {
+ /* output */
+ ogg_stream_state os ;
+ int header_handled ;
+ ogg_int64_t base_packet_no ;
+ ogg_int64_t base_granule_pos ;
+
+ /* input */
+ ogg_sync_state oy ;
+} OggContext ;
+
+
+static int ogg_write_header(AVFormatContext *avfcontext)
+{
+ OggContext *context = avfcontext->priv_data;
+ AVCodecContext *avccontext ;
+ vorbis_info vi ;
+ vorbis_dsp_state vd ;
+ vorbis_comment vc ;
+ vorbis_block vb ;
+ ogg_packet header, header_comm, header_code ;
+ int n ;
+
+ srand(time(NULL));
+ ogg_stream_init(&context->os, rand());
+
+ for(n = 0 ; n < avfcontext->nb_streams ; n++) {
+ avccontext = &avfcontext->streams[n]->codec ;
+
+ /* begin vorbis specific code */
+
+ vorbis_info_init(&vi) ;
+
+ /* code copied from libavcodec/oggvorbis.c */
+
+ if(oggvorbis_init_encoder(&vi, avccontext) < 0) {
+ fprintf(stderr, "ogg_write_header: init_encoder failed") ;
+ return -1 ;
+ }
+
+ vorbis_analysis_init(&vd, &vi) ;
+ vorbis_block_init(&vd, &vb) ;
+
+ vorbis_comment_init(&vc) ;
+ vorbis_comment_add_tag(&vc, "encoder", "ffmpeg") ;
+ if(*avfcontext->title)
+ vorbis_comment_add_tag(&vc, "title", avfcontext->title) ;
+
+ vorbis_analysis_headerout(&vd, &vc, &header,
+ &header_comm, &header_code) ;
+ ogg_stream_packetin(&context->os, &header) ;
+ ogg_stream_packetin(&context->os, &header_comm) ;
+ ogg_stream_packetin(&context->os, &header_code) ;
+
+ vorbis_block_clear(&vb) ;
+ vorbis_dsp_clear(&vd) ;
+ vorbis_info_clear(&vi) ;
+ vorbis_comment_clear(&vc) ;
+
+ /* end of vorbis specific code */
+
+ context->header_handled = 0 ;
+ context->base_packet_no = 0 ;
+ }
+
+ return 0 ;
+}
+
+
+static int ogg_write_packet(AVFormatContext *avfcontext,
+ int stream_index,
+ unsigned char *buf, int size, int force_pts)
+{
+ OggContext *context = avfcontext->priv_data ;
+ ogg_packet *op ;
+ ogg_page og ;
+ int l = 0 ;
+
+ /* 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 ;
+ }
+
+ while(l < size) {
+ op = (ogg_packet*)(buf + l) ;
+ op->packet = buf + l + sizeof(ogg_packet) ; /* fix data pointer */
+
+ if(!context->base_packet_no) { /* this is the first packet */
+ context->base_packet_no = op->packetno ;
+ context->base_granule_pos = op->granulepos ;
+ }
+
+ /* correct the fields in the packet -- essential for streaming */
+
+ op->packetno -= context->base_packet_no ;
+ op->granulepos -= context->base_granule_pos ;
+
+ ogg_stream_packetin(&context->os, op) ;
+ l += sizeof(ogg_packet) + op->bytes ;
+
+ 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);
+ }
+ }
+
+ 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,
+} ;
+
+
+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;
+ char *buf ;
+ ogg_page og ;
+ AVStream *ast ;
+
+ 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 -EIO ;
+
+ 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 ;
+
+ ast->codec.codec_type = CODEC_TYPE_AUDIO ;
+ ast->codec.codec_id = CODEC_ID_VORBIS ;
+
+ return 0 ;
+}
+
+
+static int ogg_read_packet(AVFormatContext *avfcontext, AVPacket *pkt) {
+ ogg_packet op ;
+
+ if(next_packet(avfcontext, &op))
+ return -EIO ;
+ if(av_new_packet(pkt, sizeof(ogg_packet) + op.bytes) < 0)
+ return -EIO ;
+ pkt->stream_index = 0 ;
+ memcpy(pkt->data, &op, sizeof(ogg_packet)) ;
+ memcpy(pkt->data + sizeof(ogg_packet), op.packet, op.bytes) ;
+
+ return sizeof(ogg_packet) + op.bytes ;
+}
+
+
+static int ogg_read_close(AVFormatContext *avfcontext) {
+ OggContext *context = avfcontext->priv_data ;
+
+ ogg_stream_clear(&context->os) ;
+ ogg_sync_clear(&context->oy) ;
+
+ 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) {
+ av_register_output_format(&ogg_oformat) ;
+ av_register_input_format(&ogg_iformat);
+ return 0 ;
+}
projects / synfig.git / blobdiff