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baseparse: seek table and accurate seek support

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Mark Nauwelaerts 2010-09-22 12:13:12 +02:00 committed by Tim-Philipp Müller
parent 5a69aa4903
commit 5dd8a489d5
1 changed files with 187 additions and 44 deletions
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231
gst/audioparsers/gstbaseparse.c
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@ -259,8 +259,21 @@ struct _GstBaseParsePrivate
/* ts and offset of last entry added */
GstClockTime index_last_ts;
guint64 index_last_offset;
/* timestamps currently produced are accurate, e.g. started from 0 onwards */
gboolean exact_position;
/* seek events are temporarily kept to match them with newsegments */
GSList *pending_seeks;
};
typedef struct _GstBaseParseSeek
{
GstSegment segment;
gboolean accurate;
gint64 offset;
GstClockTime start_ts;
} GstBaseParseSeek;
static GstElementClass *parent_class = NULL;
static void gst_base_parse_class_init (GstBaseParseClass * klass);
@ -485,6 +498,7 @@ gst_base_parse_reset (GstBaseParse * parse)
parse->priv->index_last_offset = 0;
parse->priv->upstream_seekable = FALSE;
parse->priv->idx_interval = 0;
parse->priv->exact_position = TRUE;
if (parse->pending_segment)
gst_event_unref (parse->pending_segment);
@ -498,6 +512,11 @@ gst_base_parse_reset (GstBaseParse * parse)
gst_buffer_unref (parse->priv->cache);
parse->priv->cache = NULL;
}
g_slist_foreach (parse->priv->pending_seeks, (GFunc) g_free, NULL);
g_slist_free (parse->priv->pending_seeks);
parse->priv->pending_seeks = NULL;
GST_OBJECT_UNLOCK (parse);
}
@ -679,57 +698,86 @@ gst_base_parse_sink_eventfunc (GstBaseParse * parse, GstEvent * event)
{
gdouble rate, applied_rate;
GstFormat format;
gint64 start, stop, pos, offset = 0;
gint64 start, stop, pos, next_ts, offset = 0;
gboolean update;
gst_event_parse_new_segment_full (event, &update, &rate, &applied_rate,
&format, &start, &stop, &pos);
GST_DEBUG_OBJECT (parse, "newseg rate %g, applied rate %g, "
"format %d, start = %" GST_TIME_FORMAT ", stop = %" GST_TIME_FORMAT
", pos = %" GST_TIME_FORMAT, rate, applied_rate, format,
GST_TIME_ARGS (start), GST_TIME_ARGS (stop), GST_TIME_ARGS (pos));
if (format == GST_FORMAT_BYTES) {
GstClockTime seg_start, seg_stop, seg_pos;
GstClockTime seg_start, seg_stop;
GstBaseParseSeek *seek = NULL;
GSList *node;
/* stop time is allowed to be open-ended, but not start & pos */
seg_stop = GST_CLOCK_TIME_NONE;
seg_start = 0;
offset = pos;
if (gst_base_parse_convert (parse, GST_FORMAT_BYTES, start,
GST_FORMAT_TIME, (gint64 *) & seg_start) &&
gst_base_parse_convert (parse, GST_FORMAT_BYTES, pos,
GST_FORMAT_TIME, (gint64 *) & seg_pos)) {
gst_event_unref (event);
event = gst_event_new_new_segment_full (update, rate, applied_rate,
GST_FORMAT_TIME, seg_start, seg_stop, seg_pos);
format = GST_FORMAT_TIME;
GST_DEBUG_OBJECT (parse, "Converted incoming segment to TIME. "
"start = %" GST_TIME_FORMAT ", stop = %" GST_TIME_FORMAT
", pos = %" GST_TIME_FORMAT, GST_TIME_ARGS (seg_start),
GST_TIME_ARGS (seg_stop), GST_TIME_ARGS (seg_pos));
}
}
GST_OBJECT_LOCK (parse);
for (node = parse->priv->pending_seeks; node; node = node->next) {
GstBaseParseSeek *tmp = node->data;
if (format != GST_FORMAT_TIME) {
if (tmp->offset == pos) {
seek = tmp;
break;
}
}
parse->priv->pending_seeks =
g_slist_remove (parse->priv->pending_seeks, seek);
GST_OBJECT_UNLOCK (parse);
if (seek) {
GST_DEBUG_OBJECT (parse,
"Matched newsegment to%s seek: %" GST_SEGMENT_FORMAT,
seek->accurate ? " accurate" : "", &seek->segment);
seg_start = seek->segment.start;
seg_stop = seek->segment.stop;
next_ts = seek->start_ts;
parse->priv->exact_position = seek->accurate;
g_free (seek);
} else {
/* best attempt convert */
/* as these are only estimates, stop is kept open-ended to avoid
* premature cutting */
gst_base_parse_convert (parse, GST_FORMAT_BYTES, start,
GST_FORMAT_TIME, (gint64 *) & seg_start);
parse->priv->exact_position = (start == 0);
next_ts = seg_start;
}
gst_event_unref (event);
event = gst_event_new_new_segment_full (update, rate, applied_rate,
GST_FORMAT_TIME, seg_start, seg_stop, seg_start);
format = GST_FORMAT_TIME;
start = seg_start;
stop = seg_stop;
GST_DEBUG_OBJECT (parse, "Converted incoming segment to TIME. "
"start = %" GST_TIME_FORMAT ", stop = %" GST_TIME_FORMAT,
GST_TIME_ARGS (seg_start), GST_TIME_ARGS (seg_stop));
} else if (format != GST_FORMAT_TIME) {
/* Unknown incoming segment format. Output a default open-ended
* TIME segment */
gst_event_unref (event);
event = gst_event_new_new_segment_full (update, rate, applied_rate,
GST_FORMAT_TIME, 0, GST_CLOCK_TIME_NONE, 0);
format = GST_FORMAT_TIME;
next_ts = start = 0;
stop = GST_CLOCK_TIME_NONE;
} else {
/* not considered BYTE seekable if it is talking to us in TIME,
* whatever else it might claim */
parse->priv->upstream_seekable = FALSE;
next_ts = start;
}
gst_event_parse_new_segment_full (event, &update, &rate, &applied_rate,
&format, &start, &stop, &pos);
gst_segment_set_newsegment_full (&parse->segment, update, rate,
applied_rate, format, start, stop, pos);
GST_DEBUG_OBJECT (parse, "Created newseg rate %g, applied rate %g, "
"format %d, start = %" GST_TIME_FORMAT ", stop = %" GST_TIME_FORMAT
", pos = %" GST_TIME_FORMAT, rate, applied_rate, format,
GST_TIME_ARGS (start), GST_TIME_ARGS (stop), GST_TIME_ARGS (pos));
applied_rate, format, start, stop, start);
/* save the segment for later, right before we push a new buffer so that
* the caps are fixed and the next linked element can receive
@ -745,7 +793,7 @@ gst_base_parse_sink_eventfunc (GstBaseParse * parse, GstEvent * event)
gst_adapter_clear (parse->adapter);
parse->priv->offset = offset;
parse->priv->sync_offset = offset;
parse->priv->next_ts = start;
parse->priv->next_ts = next_ts;
parse->priv->discont = TRUE;
break;
}
@ -1330,7 +1378,7 @@ gst_base_parse_push_buffer (GstBaseParse * parse, GstBuffer * buffer)
/* segment times are typically estimates,
* actual frame data might lead subclass to different timestamps,
* so override segment start from what is supplied there */
if (G_UNLIKELY (parse->pending_segment &&
if (G_UNLIKELY (parse->pending_segment && !parse->priv->exact_position &&
GST_CLOCK_TIME_IS_VALID (last_start))) {
gst_event_unref (parse->pending_segment);
parse->segment.start =
@ -1423,7 +1471,11 @@ gst_base_parse_push_buffer (GstBaseParse * parse, GstBuffer * buffer)
parse->priv->pending_events = NULL;
}
/* TODO: Add to seek table */
if (parse->priv->upstream_seekable && parse->priv->exact_position &&
GST_BUFFER_TIMESTAMP_IS_VALID (buffer))
gst_base_parse_add_index_entry (parse, GST_BUFFER_OFFSET (buffer),
GST_BUFFER_TIMESTAMP (buffer),
!GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DELTA_UNIT), FALSE);
if (klass->pre_push_buffer)
ret = klass->pre_push_buffer (parse, buffer);
@ -2429,6 +2481,52 @@ gst_base_parse_query (GstPad * pad, GstQuery * query)
return res;
}
static gint64
gst_base_parse_find_offset (GstBaseParse * parse, GstClockTime time,
gboolean before, GstClockTime * _ts)
{
gint64 bytes = 0, ts = 0;
GstIndexEntry *entry = NULL;
if (time == GST_CLOCK_TIME_NONE) {
ts = time;
bytes = -1;
goto exit;
}
GST_OBJECT_LOCK (parse);
if (parse->priv->index) {
/* Let's check if we have an index entry for that time */
entry = gst_index_get_assoc_entry (parse->priv->index,
parse->priv->index_id,
before ? GST_INDEX_LOOKUP_BEFORE : GST_INDEX_LOOKUP_AFTER,
GST_ASSOCIATION_FLAG_KEY_UNIT, GST_FORMAT_TIME, time);
}
if (entry) {
gst_index_entry_assoc_map (entry, GST_FORMAT_BYTES, &bytes);
gst_index_entry_assoc_map (entry, GST_FORMAT_TIME, &ts);
GST_DEBUG_OBJECT (parse, "found index entry for %" GST_TIME_FORMAT
" at %" GST_TIME_FORMAT ", offset %" G_GINT64_FORMAT,
GST_TIME_ARGS (time), GST_TIME_ARGS (ts), bytes);
} else {
GST_DEBUG_OBJECT (parse, "no index entry found for %" GST_TIME_FORMAT,
GST_TIME_ARGS (time));
if (!before) {
bytes = -1;
ts = GST_CLOCK_TIME_NONE;
}
}
GST_OBJECT_UNLOCK (parse);
exit:
if (_ts)
*_ts = ts;
return bytes;
}
/**
* gst_base_parse_handle_seek:
@ -2445,10 +2543,11 @@ gst_base_parse_handle_seek (GstBaseParse * parse, GstEvent * event)
GstFormat format;
GstSeekFlags flags;
GstSeekType cur_type = GST_SEEK_TYPE_NONE, stop_type;
gboolean flush, update, res = TRUE;
gint64 cur, stop, seekpos;
gboolean flush, update, res = TRUE, accurate;
gint64 cur, stop, seekpos, seekstop;
GstSegment seeksegment = { 0, };
GstFormat dstformat;
GstClockTime start_ts;
klass = GST_BASE_PARSE_GET_CLASS (parse);
@ -2492,14 +2591,40 @@ gst_base_parse_handle_seek (GstBaseParse * parse, GstEvent * event)
gst_segment_set_seek (&seeksegment, rate, format, flags,
cur_type, cur, stop_type, stop, &update);
dstformat = GST_FORMAT_BYTES;
if (!gst_pad_query_convert (parse->srcpad, format, seeksegment.last_stop,
&dstformat, &seekpos))
goto convert_failed;
/* accurate seeking implies seek tables are used to obtain position,
* and the requested segment is maintained exactly, not adjusted any way */
accurate = flags & GST_SEEK_FLAG_ACCURATE;
/* maybe we can be accurate for (almost) free */
if (seeksegment.last_stop <= parse->priv->index_last_ts + 20 * GST_SECOND) {
GST_DEBUG_OBJECT (parse,
"seek position %" GST_TIME_FORMAT " <= %" GST_TIME_FORMAT
"accurate seek possible", GST_TIME_ARGS (seeksegment.last_stop),
GST_TIME_ARGS (parse->priv->index_last_ts));
accurate = TRUE;
}
if (accurate) {
seekpos = gst_base_parse_find_offset (parse, seeksegment.last_stop, TRUE,
&start_ts);
seekstop = gst_base_parse_find_offset (parse, seeksegment.stop, FALSE,
NULL);
} else {
start_ts = seeksegment.last_stop;
dstformat = GST_FORMAT_BYTES;
if (!gst_pad_query_convert (parse->srcpad, format, seeksegment.last_stop,
&dstformat, &seekpos))
goto convert_failed;
if (!gst_pad_query_convert (parse->srcpad, format, seeksegment.stop,
&dstformat, &seekstop))
goto convert_failed;
}
GST_DEBUG_OBJECT (parse,
"seek position %" G_GINT64_FORMAT " in bytes: %" G_GINT64_FORMAT, cur,
seekpos);
GST_DEBUG_OBJECT (parse,
"seek stop %" G_GINT64_FORMAT " in bytes: %" G_GINT64_FORMAT,
seeksegment.stop, seekstop);
if (parse->priv->pad_mode == GST_ACTIVATE_PULL) {
gint64 last_stop;
@ -2573,8 +2698,9 @@ gst_base_parse_handle_seek (GstBaseParse * parse, GstEvent * event)
"mark DISCONT, we did a seek to another position");
parse->priv->offset = seekpos;
parse->priv->discont = TRUE;
parse->priv->next_ts = parse->segment.last_stop;
parse->priv->next_ts = start_ts;
parse->priv->sync_offset = seekpos;
parse->priv->exact_position = accurate;
}
/* Start streaming thread if paused */
@ -2584,22 +2710,39 @@ gst_base_parse_handle_seek (GstBaseParse * parse, GstEvent * event)
GST_PAD_STREAM_UNLOCK (parse->sinkpad);
} else {
GstEvent *new_event;
gint64 stop_pos;
GstBaseParseSeek *seek;
/* The only thing we need to do in PUSH-mode is to send the
seek event (in bytes) to upstream. Segment / flush handling happens
in corresponding src event handlers */
GST_DEBUG_OBJECT (parse, "seek in PUSH mode");
/* already converted start, need same for stop */
dstformat = GST_FORMAT_BYTES;
if (!gst_pad_query_convert (parse->srcpad, format, seeksegment.start,
&dstformat, &stop_pos))
goto convert_failed;
new_event = gst_event_new_seek (rate, GST_FORMAT_BYTES, flush,
GST_SEEK_TYPE_SET, seekpos, stop_type, stop_pos);
GST_SEEK_TYPE_SET, seekpos, stop_type, seekstop);
/* store segment info so its precise details can be reconstructed when
* receiving newsegment;
* this matters for all details when accurate seeking,
* is most useful to preserve NONE stop time otherwise */
seek = g_new0 (GstBaseParseSeek, 1);
seek->segment = seeksegment;
seek->accurate = accurate;
seek->offset = seekpos;
seek->start_ts = start_ts;
GST_OBJECT_LOCK (parse);
/* less optimal, but preserves order */
parse->priv->pending_seeks =
g_slist_append (parse->priv->pending_seeks, seek);
GST_OBJECT_UNLOCK (parse);
res = gst_pad_push_event (parse->sinkpad, new_event);
if (!res) {
GST_OBJECT_LOCK (parse);
parse->priv->pending_seeks =
g_slist_remove (parse->priv->pending_seeks, seek);
GST_OBJECT_UNLOCK (parse);
g_free (seek);
}
}
done: