| $Id$ |
| |
| Currently its only save to link/unlink elements/pad when pipeline is in READY. |
| Belowe some thoughts. See http://bugzilla.gnome.org/show_bug.cgi?id=435487 |
| for patches. |
| |
| = current api = |
| |
| gboolean gst_element_link (GstElement *src, GstElement *dest); |
| void gst_element_unlink (GstElement *src, GstElement *dest); |
| |
| gst_element_link_many, gst_element_unlink_many, gst_element_link_filtered, |
| gst_element_link_pads, gst_element_unlink_pads, gst_element_link_pads_filtered |
| |
| GstPadLinkReturn gst_pad_link (GstPad *srcpad, GstPad *sinkpad); |
| gboolean gst_pad_unlink (GstPad *srcpad, GstPad *sinkpad); |
| |
| = use cases = |
| |
| == inserting an element == |
| |
| * we have: e1 ! e4 |
| * we want: e1 ! e2 ! e3 ! e4 |
| * we want: e1 ! e2 ! e4 |
| |
| gst_element_insert_linked(e1, e2, e3, e4); // e2 == e3 allowed |
| gst_pads_insert_link (e1.src, e2.sink, e3.src, e4.sink); |
| disconnect e1.src, e1.src.peer |
| disconnect e4.sink, e4.sink.peer |
| connect e1.src, e2.sink |
| connect e3.src, e4.sink |
| |
| == removing an element == |
| |
| * we have: e1 ! e2 ! e3 |
| * we want: e1 ! e3 |
| |
| gst_element_remove_linked(e2); |
| gst_pads_remove_link (e1.src, e3.sink); |
| disconnect e1.src, e1.src.peer |
| disconnect e3.sink, e3.sink.peer |
| connect e1.src, e3.sink |
| |
| == swapping out an elelment == |
| |
| * we have: e1 ! e2 ! e6 |
| * we have: e1 ! e2 ! e3 ! e6 |
| * we want: e1 ! e4 ! e5 ! e6 |
| * we want: e1 ! e3 ! e6 |
| |
| gst_element_swap_linked(e1, e4, e5, e6); |
| gst_pads_insert_link (e1.src, e4.sink, e5.src, e6.sink); |
| disconnect e1.src, e1.src.peer (=e2.sink) |
| disconnect e6.sink, e6.sink.peer |
| connect e1.src, e4.sink |
| connect e5.src, e6.sink |
| |
| = thoughts = |
| * I don't think we need api for pads |
| * Should current api check for the state? |
| * do we want to swapp multiple elements at once |
| |
| == events == |
| * tee and adder need special treatment |
| * both would need to cache an accumulated segment |
| * tee |
| * would also cache tags |
| * when linkfunc is called, it can send out the segment and the tags |
| * when all pads got unlinked it could clear the segment |
| * adder |
| * when linkfunc gets called it sends a seek-event |
| |
| = ideas = |
| == dynlinkpoint == |
| * use cases |
| * its ment to be used with one side disconnected to allow to connect elements |
| at runtime |
| * it can be used in a pipeline to remove/insert elements at runtime |
| * element with 1 source- and 1 sinkpad |
| * when both connected it passes data thru |
| * if src is not connected it drops received buffers |
| * if sink is not conected |
| * it does not push |
| * it creates silence on pull |
| * events |
| * it caches events |
| * down: newsegment, tags, buffersize |
| * up: seek (needs to be modified) |
| * when other-pad get connected it pushes events depending on direction |
