There is a race going on somewhere when we attempt to remove elements
*while* the parent container is switching to PLAYING.
In order to avoid this issue with discoverer, make sure we never
remove elements while switching to PLAYING.
This would result in a lot of warnings regarding elements not being
in NULL state when removed, or even leaked elements.
Instead make sure we take the lock and check whether we are processing
or not before allocating or adding anything to the pipeline
And monitor no_more_pads.
With live sources such as rtsp, uridecodebin only creates its
child decodebins between PAUSED and PLAYING.
This means that the ASYNC_DONE it posts when getting NO_PREROLL
in its change_state method gets immediately propagated by the
GstBin parent class, as opposed to a situation where a
decodebin has been added to it already, and has posted ASYNC_START.
The proposed solution, instead of simply waiting for ASYNC_DONE,
and finishing prematurely in that case, waits for three conditions
to be true:
* the uridecodebin needs to have emitted no_more_pads
* its current state must be PAUSED if not live, PLAYING otherwise
* There must be no "pending subtitle pads", ie pads where we haven't
received tags yet.
All these conditions are checked in the message handler, as we
post custom messages on it when we get subtitle tags or no_more_pads.
https://bugzilla.gnome.org/show_bug.cgi?id=783257
Child streams could have more accurate width/height or various other
information added. If they have the same name, they are likely to be the
same streams.
https://bugzilla.gnome.org/show_bug.cgi?id=782697
The parser might do some conversion on a stream but the stream keeps
being the same, and we need to make sure GstDiscoverer detects it is the
case.
https://bugzilla.gnome.org/show_bug.cgi?id=778298
The caps put into the stream topology by decodebin are the caps at the
moment the pads are exposed on it. This is usually before decoders
received any buffers.
In discoverer we however wait for pre-roll, which ensures that each
decoder handled buffers already. At this point, there might be more
information known about the caps already that we could make use of.
One example here is extra information stored in the SEI of H264, like
the multiview-mode. This will be known if there is a SEI before the
first keyframe, but decodebin won't put this into the topology as it
only waits for the initial caps of h264parse (which come directly after
SPS/PPS).
With this change, the multiview-mode is in the caps reported by
discoverer in many cases.
The caps might not be fixated (which is required by GstVideoInfo) and we
would assert otherwise. However the caps often contain useful
information in the already-fixed parts that we can use here.
[API] gst_discoverer_info_to_variant
[API] gst_discoverer_info_from_variant
[API] GstDiscovererSerializeFlags
+ Serializes as a GVariant
+ Adds a test
+ Does not serialize potential GstToc (s)
https://bugzilla.gnome.org/show_bug.cgi?id=748814
gst_message_parse_toc() returns a reffed GstToc which is owned by the
GstDiscovererInfo. But we have to make sure we unref its previous value before
setting the new one.
https://bugzilla.gnome.org/show_bug.cgi?id=747103
This avoids a race where we would get new tag but we are already
prerolled and analyzing results.
It is the way it is supposed to be handled as stated in comment:
"If preroll is complete, drop these tags - the collected information is
possibly already being processed and adding more tags would be racy"
Otherwize the pipeline would be in an wrong state and on the next
iteration any kind of error could happen
Everytime an error happens in a pipeline the application has to set the
pipeline back to NULL instead of READY.
https://bugzilla.gnome.org/show_bug.cgi?id=733976
Currently the API is far from optimal and the user has to work around
our badly defined API to simply install missing plugins.
API:
new:
gst_discoverer_info_get_missing_elements_installer_details
deprecated:
gst_discoverer_info_get_misc
gst_discoverer_stream_info_get_misc
https://bugzilla.gnome.org/show_bug.cgi?id=720596
We're checking the caps to see if we got more caps details after a parser got
plugged. This will also have a flipped 'parsed' field. If the field was already
present before the parse the match will fail. Add a function that will do the
check while excluding this field.
