GNOME Bugzilla – Bug 639216
controller: add API for elements to get future property values
Last modified: 2011-01-11 20:19:41 UTC
Intended for use by elements that need to see property changes for future timestamp values. For example bracketing camera src which needs to pre-program the hardware or driver for exposure (or other) settings so that the settings change can be properly synchronized with the capture.
Created attachment 178043 [details] [review] [PATCH] controller: API for elements to "peek" future values
The point of gst_controller_sync_values() is that the value can be taken from the normal property and the app can also see the current value. If we need multiple values we could use gst_controller_get_value_arrays(). The element can preparse the data-structures and reuse them.
I have to agree with Stefan... can we close this bug as NOTABUG then?
maybe.. at first glance it looks like this could work. But unless I'm overlooking something, I think then we'd need to add an API to find the names of the controlled properties.
Take a look at the volume element, which does exactly what you want :) gst_object_get_control_source (G_OBJECT (self), property_name) returns NULL if the property is not controlled.
Having something like gst_object_get_controlled_properties() might be nice, but I guess there is a finite set of properties that would be controllable so I guess it is not strictly needed.
Well the element itself will know which ones are controllable :) Apps should just loop over them. there is no API for g_object_class_get_writable_properties() either.