AppSink.tryPullPreroll

Get the last preroll sample in appsink. This was the sample that caused the appsink to preroll in the PAUSED state.

This function is typically used when dealing with a pipeline in the PAUSED state. Calling this function after doing a seek will give the sample right after the seek position.

Calling this function will clear the internal reference to the preroll buffer.

Note that the preroll sample will also be returned as the first sample when calling [gstapp.app_sink.AppSink.pullSample].

If an EOS event was received before any buffers or the timeout expires, this function returns null. Use gst_app_sink_is_eos () to check for the EOS condition.

This function blocks until a preroll sample or EOS is received, the appsink element is set to the READY/NULL state, or the timeout expires.