Queries an element (usually top-level pipeline or playbin element) for the
total stream duration in nanoseconds. This query will only work once the
pipeline is prerolled (i.e. reached PAUSED or PLAYING state). The application
will receive an ASYNC_DONE message on the pipeline bus when that is the case.
If the duration changes for some reason, you will get a DURATION_CHANGED
message on the pipeline bus, in which case you should re-query the duration
using this function.
Queries an element (usually top-level pipeline or playbin element) for the total stream duration in nanoseconds. This query will only work once the pipeline is prerolled (i.e. reached PAUSED or PLAYING state). The application will receive an ASYNC_DONE message on the pipeline bus when that is the case. If the duration changes for some reason, you will get a DURATION_CHANGED message on the pipeline bus, in which case you should re-query the duration using this function.