static int vorbis_packet(AVFormatContext *s, int idx) { struct ogg *ogg = s->priv_data; struct ogg_stream *os = ogg->streams + idx; struct oggvorbis_private *priv = os->private; int duration; /* first packet handling here we parse the duration of each packet in the first page and compare the total duration to the page granule to find the encoder delay and set the first timestamp */ if (!os->lastpts) { int seg; uint8_t *last_pkt = os->buf + os->pstart; uint8_t *next_pkt = last_pkt; int first_duration = 0; avpriv_vorbis_parse_reset(&priv->vp); duration = 0; for (seg = 0; seg < os->nsegs; seg++) { if (os->segments[seg] < 255) { int d = avpriv_vorbis_parse_frame(&priv->vp, last_pkt, 1); if (d < 0) { duration = os->granule; break; } if (!duration) first_duration = d; duration += d; last_pkt = next_pkt + os->segments[seg]; } next_pkt += os->segments[seg]; } os->lastpts = os->lastdts = os->granule - duration; s->streams[idx]->start_time = os->lastpts + first_duration; if (s->streams[idx]->duration) s->streams[idx]->duration -= s->streams[idx]->start_time; s->streams[idx]->cur_dts = AV_NOPTS_VALUE; priv->final_pts = AV_NOPTS_VALUE; avpriv_vorbis_parse_reset(&priv->vp); } /* parse packet duration */ if (os->psize > 0) { duration = avpriv_vorbis_parse_frame(&priv->vp, os->buf + os->pstart, 1); if (duration <= 0) { os->pflags |= AV_PKT_FLAG_CORRUPT; return 0; } os->pduration = duration; } /* final packet handling here we save the pts of the first packet in the final page, sum up all packet durations in the final page except for the last one, and compare to the page granule to find the duration of the final packet */ if (os->flags & OGG_FLAG_EOS) { if (os->lastpts != AV_NOPTS_VALUE) { priv->final_pts = os->lastpts; priv->final_duration = 0; } if (os->segp == os->nsegs) os->pduration = os->granule - priv->final_pts - priv->final_duration; priv->final_duration += os->pduration; } return 0; }
static int vorbis_packet(AVFormatContext *s, int idx) { struct ogg *ogg = s->priv_data; struct ogg_stream *os = ogg->streams + idx; struct oggvorbis_private *priv = os->private; int duration;   if (!os->lastpts) { int seg; uint8_t *last_pkt = os->buf + os->pstart; uint8_t *next_pkt = last_pkt; int first_duration = 0; avpriv_vorbis_parse_reset(&priv->vp); duration = 0; for (seg = 0; seg < os->nsegs; seg++) { if (os->segments[seg] < 255) { int d = avpriv_vorbis_parse_frame(&priv->vp, last_pkt, 1); if (d < 0) { duration = os->granule; break; } if (!duration) first_duration = d; duration += d; last_pkt = next_pkt + os->segments[seg]; } next_pkt += os->segments[seg]; } os->lastpts = os->lastdts = os->granule - duration; s->streams[idx]->start_time = os->lastpts + first_duration; if (s->streams[idx]->duration) s->streams[idx]->duration -= s->streams[idx]->start_time; s->streams[idx]->cur_dts = AV_NOPTS_VALUE; priv->final_pts = AV_NOPTS_VALUE; avpriv_vorbis_parse_reset(&priv->vp); }   if (os->psize > 0) { duration = avpriv_vorbis_parse_frame(&priv->vp, os->buf + os->pstart, 1); if (duration <= 0) { os->pflags |= AV_PKT_FLAG_CORRUPT; return 0; } os->pduration = duration; }   if (os->flags & OGG_FLAG_EOS) { if (os->lastpts != AV_NOPTS_VALUE) { priv->final_pts = os->lastpts; priv->final_duration = 0; } if (os->segp == os->nsegs) os->pduration = os->granule - priv->final_pts - priv->final_duration; priv->final_duration += os->pduration; } return 0; }