Applies some suggestions based on reviews by vstoiakin regarding concurrent resource access and overall structural simplification.
- Create and handoff ownership of QVideoFrames each frame
- use QReadWriteLocks when multiple reads are possible instead of QMutex
- remove the superfluous layer of unique_ptrs on QVideoFrames which are explicitly shared using QExplicitlySharedDataPointer for their underlying data.
This patch is required to prevent crashes when using Qt 6.4 and up.
Gitlab: #938
Change-Id: Ia9a9f0310344bcee47dbd88ec622bc3daa2ce6d7
We can observe that frame update signals can occur after a VideoOutput component's QVideoSink object has started destruction. The deregistration of the object pointer needs to be synchronized to the object's destruction.
Additionally:
+ scope the frame obj mutex locker around checks for no subs
+ rename (un)registerSink to (un)subscribe
+ subscribe will now remove the previous subscription
+ subscribe with an empty id will unsubscribe
Gitlab: #997
Change-Id: I21460564e49189b9276f153e8c1fd3a5cc52c6b2
