API: GstBaseParseClass::detect()
This is called with the first buffers until the subclass has finished detection
and only afterwards the original buffers are handled as before. The vfunc allows
detection of the stream format without breaking the upstream framing.
Adds a getcaps function to the sink pad to make parsers propagate
downstream caps restrictions to upstream.
The pipeline "audiotestsrc num-buffers=100 ! faac ! aacparse !
"audio/mpeg, version=(int)4, stream-format=(string)adts" ! filesink"
wouldn't work because aacparse wouldn't propagate the adts restriction
upstream to faac.
This patch adds a default getcaps to the sink pad to simply proxy
downstream caps and also adds a 'get_sink_caps' function pointer
to GstBaseParseClass for subclasses that need more refined getcaps.
https://bugzilla.gnome.org/show_bug.cgi?id=661874
Some elements (such as videorate) might push buffers early,
for instance in in transform_ip. We want events (and in particular
any NEWSEGMENT event) to be pushed before that.
This fixes transmageddon wedging on converting a file starting
with a non zero offset to Ogg.
https://bugzilla.gnome.org/show_bug.cgi?id=660165
Otherwise elements like capsfilter will return ANY caps if no
peer is present instead of the filter caps. The transform_caps()
vfunc could do transformations to the template caps that do not
result in the unmodified template caps.
Wim suggested that using GstPadDirection instead of a GstPad in the
arguments to the new query vfunc would be more consistent with the other
functions.
This allows subclass to indicate that size reported by src may not be static
and should as such be updated regularly, rather than only when really
needed.
Particular examples are filesrc or fdsrc reading from a file that is still
growing (e.g. being downloaded).
Fixes#652037.
This reverts commit 934faf163c.
Original commit leads to possibly sending newsegment event downstream
in pull mode. In push mode, quite some downstream elements
are likely to only expect newsegment event following a seek they performed
and as such may have their state messed up.
While some formats allow subclass to determine a specific subsequent
needed frame size, others may to need to scan for markers and can only
request 'additional data' by whatever reasonable available step.
In push mode, trying to minimize additional latency leads to step size
being the next input buffer. In pull mode, any reasonable step size
(such as already used by buffer caching) can be applied.
Doing so avoids a large timestamp gap between first and second buffer
for live sources which take time to start up.
The first buffer now has a "live" timestamp based on the running time,
as other buffers do.
https://bugzilla.gnome.org/show_bug.cgi?id=649369
