rtsp-media: emit signal for preparing dynamic payloads
Submitted by George Kiagiadakis
Created attachment 304268
When using dynamic payloads, it is useful to know when rtsp-media has connected to the pad-added signal, so that the application code can continue to add those pads. If the dynpay element is a decodebin, the pads are always added after the element changes state to PAUSED, which is set after connecting the pad-added signal internally and therefore it works fine. However, there can be other cases where the application needs to add the pads externally and therefore it needs to know when is the right moment to do so.
This patch adds a "preparing" signal that is emitted at the end of start_prepare, and compliments the "prepared" and "unprepared" signals.
Patch 304268, "patch":