mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-11-19 00:01:23 +00:00
67 lines
1.6 KiB
Text
67 lines
1.6 KiB
Text
|
1) transitions
|
||
|
|
--------------
|
||
|
|
|
||
|
|
There are four states, NULL, READY, PAUSED, PLAYING. state transitions only
|
||
|
|
happen from once neighbouring state to another.
|
||
|
|
|
||
|
|
NULL: the element is just being created, the initial state.
|
||
|
|
!
|
||
|
|
! the element creates all of its resources (a thread will create
|
||
|
|
! its pthread etc..)
|
||
|
|
! - most used by bins to set up thread context for its children
|
||
|
|
v
|
||
|
|
READY: the element is ready to start processing.
|
||
|
|
!
|
||
|
|
! the element sets up its state so it can start processing buffers.
|
||
|
|
! - open devices
|
||
|
|
v
|
||
|
|
PAUSED: the element is paused
|
||
|
|
!
|
||
|
|
! the element starts spinning
|
||
|
|
!
|
||
|
|
v
|
||
|
|
PLAYING: the element is playing
|
||
|
|
!
|
||
|
|
! the element stops spinning
|
||
|
|
! the element frees resources from other plugins (bufferpools)
|
||
|
|
!
|
||
|
|
v
|
||
|
|
PAUSED
|
||
|
|
! element removes caps from pads
|
||
|
|
! reset internal state
|
||
|
|
! - close devices
|
||
|
|
!
|
||
|
|
v
|
||
|
|
READY
|
||
|
|
!
|
||
|
|
! the element frees all of its resources (eg: pthread_join)
|
||
|
|
!
|
||
|
|
v
|
||
|
|
NULL
|
||
|
|
|
||
|
|
|
||
|
|
2) bin transition
|
||
|
|
-----------------
|
||
|
|
|
||
|
|
the state of a bin is equal to the maximum state of its children.
|
||
|
|
|
||
|
|
|
||
|
|
3) interaction with the scheduler
|
||
|
|
---------------------------------
|
||
|
|
|
||
|
|
elements in the !PLAYING state are disabled in the scheduler.
|
||
|
|
|
||
|
|
|
||
|
|
4) action that can be performed by the app in the different states
|
||
|
|
------------------------------------------------------------------
|
||
|
|
|
||
|
|
PLAYING: nothing, only iterate on the pipeline, some properties can
|
||
|
|
be changed.
|
||
|
|
|
||
|
|
PAUSED: elements can be connected, removed, disconnected. some
|
||
|
|
properties can be changed
|
||
|
|
|
||
|
|
READY: as in PAUSED but *all* properties can be changed.
|
||
|
|
|
||
|
|
NULL: everything.
|