Before this patch, NLE and GES did not support NleOperations (respectively
GESEffects) that changed the speed/tempo/rate at which the source plays. For
example, the 'pitch' element can make audio play faster or slower. In GES 1.5.90
and before, an NleOperation containing the pitch element to change the rate (or
tempo) would cause a pipeline state change to PAUSED after that stack; that has
been fixed in 1.5.91 (see #755012 [0]). But even then, in 1.5.91 and later,
NleComposition would send segment events to its NleSources assuming that one
source second is equal to one pipeline second. The resulting early EOS event
(in the case of a source rate higher than 1.0) would cause it to switch stacks
too early, causing confusion in the timeline and spectacularly messed up
output.
This patch fixes that by searching for rate-changing elements in
GESTrackElements such as GESEffects. If such rate-changing elements are found,
their final effect on the playing rate is stored in the corresponding NleObject
as the 'media duration factor', named like this because the 'media duration',
or source duration, of an NleObject can be computed by multiplying the duration
with the media duration factor of that object and its parents (this is called
the 'recursive media duration factor'). For example, a 4-second NleSource with
an NleOperation with a media duration factor of 2.0 will have an 8-second media
duration, which means that for playing 4 seconds in the pipeline, the seek
event sent to it must span 8 seconds of media. (So, the 'duration' of an
NleObject or GES object always refers to its duration in the timeline, not the
media duration.)
To summarize:
* Rate-changing elements are registered in the GESEffectClass (pitch::tempo and
pitch::rate are registered by default);
* GESTimelineElement is responsible for detecting rate-changing elements and
computing the media_duration_factor;
* GESTrackElement is responsible for storing the media_duration_factor in
NleObject;
* NleComposition is responsible for the recursive_media_duration_factor;
* The latter property finally fixes media time computations in NleObject.
NLE and GES tests are included.
[0] https://bugzilla.gnome.org/show_bug.cgi?id=755012
Differential Revision: https://phabricator.freedesktop.org/D276
Read only properties will throw a GLib warning like this
when accessed with "set_child_property":
Warning: g_object_set_property: property 'text-x' of object class 'GstTextOverlay' is not writable
Avoiding all the pending_xx dance and making the code simpler.
This is now possible thanks to the various recent refactoring.
Thanks to that the user is able to set_child_property on objects
that are not in GESTrack yet, as expected.
Reviewed-by: Thibault Saunier <thibault.saunier@collabora.com>
Differential Revision: https://phabricator.freedesktop.org/D739
This way we have informations about the content of the
children as soon as possible.
Most code paths where already ready to handle that as we use it for
copying clips.
Fix framepositionner to properly handle that (it would have broke
with copied clips before).
Reviewed-by: Thibault Saunier <thibault.saunier@collabora.com>
Differential Revision: https://phabricator.freedesktop.org/D736
I got some trouble with
arc land
and I wanted to push the 3 commit coming after this revert as 3
different commits but they ended up being all squash into one single
commit, which is clearly not cool for later bisecting and blaming.
Reverting that commit and re pushing those 3 commits as they were
supposed to be.
This reverts commit 9fe15ef435.
This method can be used for subclass to override the default behaviour
for child lookup. This vmethod can be used for example in the case where
you want the name of a child property to be 'overridden'.
As an example in the GESTitleSource where we have a videotestsrc
which has a 'foreground-color' property that is used in the TitleSource
to set the background color of the title, this vmethod is now used to
tweak the name passed as parameter to rename "background" to
"foreground-backend" making our API understandable.
API:
GESTrackElement::lookup_child
https://bugzilla.gnome.org/show_bug.cgi?id=727880
g-ir-scanner includes section docs as class/interface docs if the section name is equal to the lowercase type name.
Since all the documentation is in section blocks, rename them to match the type names.
https://bugzilla.gnome.org/show_bug.cgi?id=727776
When duration or inpoint change, we need to remove edge control points,
and set new control points with interpolated values.
Also when duration == 0, we need to remove all control points, as otherwise
the controller will raise !is_end assertions.
It's the duty of the application to set keyframes back when duration gets
!= 0 again.
We should make sure that the newly created trackelement are inside
a container when adding them to as this is needed for GESUriClip-s.
Also do not try to set a child property on the TrackElement itself.
https://bugzilla.gnome.org/show_bug.cgi?id=703152
The GNL API changed to go from a model where user could
enable/disable updates in the composition, which leaded to races
in many places, to a model where any positioning change in the
composition is not directly done but 'cached' and then the user
has to commit those changes so they become effective in the media
processing stack.
The new API in GES is pretty similare and is basically copy
pasting this new design.
We still need to see if in some context it would make sense to add
a mode where we would commit any changes ourself at the end of our
operation for basic use cases.
Removed APIs:
ges_timeline_enable_update
ges_timeline_is_updating
ges_track_enable_update
ges_track_is_updating
New APIs:
ges_track_commit
ges_timeline_commit
Remove APIs:
ges_track_element_set_locked
ges_track_element_is_locked
Those APIs where really not nice to use and were causing more issues
than solving them. If 2 time related properties of TimelineElement must
be different, then those element can *not* have the same parent.
Plus, with the new ges_container_group () API, we will recreate 1
GESClip containing the proper GESTimelineElements if it is the thing
to do.
... Not the other way round.
+ Add and enhance debugging info on the way
The user should not be responsible for removing the GESTrackElements from
GESTracks, instead, removing it from a GESClip should imply removing
it from any GESTrack it is in.
This patch changes sensibly the behaviour when we remove a
GESTrackElement from a GESTrack, not remoing it from the GESClip it is
in. *But*, users should never remove a GESTrackElement from a GESTrack
anyway. The testsuite has been updated to that new behaviour.
