oggdemux: use index to estimate bitrate

When we have an index, use it to much more accurately estimate the total stream
bitrate.
This commit is contained in:
Wim Taymans 2010-05-06 10:56:21 +02:00
parent 18f07f03d1
commit 549bc3c80e
3 changed files with 28 additions and 3 deletions

View file

@ -1677,11 +1677,11 @@ gst_ogg_demux_activate_chain (GstOggDemux * ogg, GstOggChain * chain,
/* FIXME, should not be called with NULL */
if (chain != NULL) {
gint bitrate;
gint bitrate, idx_bitrate;
GST_DEBUG_OBJECT (ogg, "activating chain %p", chain);
bitrate = 0;
bitrate = idx_bitrate = 0;
/* first add the pads */
for (i = 0; i < chain->streams->len; i++) {
@ -1690,6 +1690,9 @@ gst_ogg_demux_activate_chain (GstOggDemux * ogg, GstOggChain * chain,
pad = g_array_index (chain->streams, GstOggPad *, i);
if (pad->map.idx_bitrate)
idx_bitrate = MAX (idx_bitrate, pad->map.idx_bitrate);
bitrate += pad->map.bitrate;
/* mark discont */
@ -1714,7 +1717,8 @@ gst_ogg_demux_activate_chain (GstOggDemux * ogg, GstOggChain * chain,
gst_element_add_pad (GST_ELEMENT (ogg), GST_PAD_CAST (pad));
pad->added = TRUE;
}
ogg->bitrate = bitrate;
/* prefer the index bitrate over the ones encoded in the streams */
ogg->bitrate = (idx_bitrate ? idx_bitrate : bitrate);
}
/* after adding the new pads, remove the old pads */

View file

@ -922,6 +922,26 @@ gst_ogg_map_add_index (GstOggStream * pad, const guint8 * data, guint size)
G_GUINT64_FORMAT, n_keypoints, isize);
}
pad->n_index = isize;
/* try to use the index to estimate the bitrate */
if (isize > 2) {
guint64 so, eo, st, et, b, t;
/* get start and end offset and timestamps */
so = pad->index[0].offset;
st = pad->index[0].timestamp;
eo = pad->index[isize - 1].offset;
et = pad->index[isize - 1].timestamp;
b = eo - so;
t = et - st;
GST_DEBUG ("bytes/time %" G_GUINT64_FORMAT "/%" G_GUINT64_FORMAT, b, t);
/* this is the total stream bitrate according to this index */
pad->idx_bitrate = gst_util_uint64_scale (8 * b, pad->kp_denom, t);
GST_DEBUG ("bitrate %" G_GUINT64_FORMAT, pad->idx_bitrate);
}
return TRUE;
}

View file

@ -89,6 +89,7 @@ struct _GstOggStream
guint n_index;
GstOggIndex *index;
guint64 kp_denom;
guint64 idx_bitrate;
};