mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-12-18 22:36:33 +00:00
50e2f24b44
Original commit message from CVS: * gst/playback/README: * gst/playback/gstdecodebin.c: (gst_decode_bin_class_init), (compare_ranks), (print_feature), (gst_decode_bin_init), (dynamic_create), (dynamic_free), (find_compatibles), (mimetype_is_raw), (close_pad_link), (got_redirect), (try_to_link_1), (get_our_ghost_pad), (remove_element_chain), (new_pad), (no_more_pads), (unlinked), (close_link), (type_found), (gst_decode_bin_change_state): * gst/playback/gstplaybasebin.c: (gst_play_base_bin_class_init), (gst_play_base_bin_init), (group_destroy), (group_commit), (check_queue), (queue_overrun), (queue_threshold_reached), (queue_out_of_data), (gen_preroll_element), (unknown_type), (new_decoded_pad), (setup_subtitle), (gen_source_element), (got_redirect), (setup_source), (play_base_eos), (gst_play_base_bin_change_state), (gst_play_base_bin_add_element), (gst_play_base_bin_remove_element): * gst/playback/gstplaybasebin.h: * gst/playback/gstplaybin.c: (gst_play_bin_class_init), (gst_play_bin_init), (gst_play_bin_dispose), (gst_play_bin_set_property), (gen_video_element), (gen_text_element), (gen_audio_element), (remove_sinks), (gst_play_bin_send_event): * gst/playback/gststreaminfo.c: (gst_stream_info_dispose), (stream_info_change_state), (gst_stream_info_set_mute): * gst/playback/gststreamselector.c: (gst_stream_selector_init), (gst_stream_selector_get_caps), (gst_stream_selector_setcaps), (gst_stream_selector_request_new_pad), (gst_stream_selector_event), (gst_stream_selector_chain): * gst/playback/test.c: (gen_video_element), (gen_audio_element), (main): * sys/xvimage/xvimagesink.c: (gst_xvimagesink_getcaps), (gst_xvimagesink_setcaps), (gst_xvimagesink_get_times), (gst_xvimagesink_show_frame), (gst_xvimagesink_chain), (gst_xvimagesink_buffer_alloc), (gst_xvimagesink_class_init): Raw and crude port of decodebin. Make playbin compile.
90 lines
4.1 KiB
Text
90 lines
4.1 KiB
Text
decoderbin:
|
|
|
|
A bin with a sinkpad that decodes the data into raw formats. It works by sending
|
|
the input data through a typefind element and then recursively autoplugs elements
|
|
from the registry until a raw format is obtained. It will then create a new ghostpad
|
|
on itself to signal the app of the new pad.
|
|
|
|
Decodebin will also remove pads when they are removed from the stream.
|
|
|
|
TODO
|
|
- reuse of decoderbin, cleanup in READY state
|
|
- threading after demuxing?
|
|
- new_media events should be handled.
|
|
- caching of elements.
|
|
- abstract more elements, pads (typefind, ...);
|
|
|
|
The autoplugging happens as follows:
|
|
|
|
1) typefind is added internally to the bin.
|
|
2) the have_type signal is connected to typefind.
|
|
3) in the have_type callback the close_pad_link function is called
|
|
4) close_pad_link checks the type on the pad, if it is raw, a ghostpad
|
|
is created and autoplugging for that pad stops.
|
|
5) if the type of the pad is not raw, a list of possible elements that
|
|
can connect to this type is generated in find_compatibles.
|
|
6) try_to_link_1 with the element list is called. The function will loop
|
|
over the element list and will try to connect one of the elements to
|
|
the pad. If the link works, a call is made to close_link.
|
|
7) close_link loops over all the source pads of the element and
|
|
recursively calls 4) for any ALWAYS pad. For elements with
|
|
a SOMETIMES pad, a structure is set up and is passed to the callback
|
|
of the new_pad signal.
|
|
8) in the new_pad callback, 4) is called to try to autoplug the
|
|
new pad.
|
|
|
|
|
|
playbasebin:
|
|
|
|
A bin with an uri property. It will find the right source element from the registry
|
|
and connect a decoderbin to it. When going to the PAUSED state, it will iterate the
|
|
decoderbin and listen for new pad signals from it. It will connect a queue to each
|
|
new pad and will iterate the decoderbin until one of the queues is filled. It is
|
|
assumed that by that time all the streams will be found so that when leaving the
|
|
PAUSED state, one can query the number of streams in the media file with the given
|
|
uri.
|
|
|
|
Playbasebin internally groups related streams together in a GstPlayBaseGroup. This
|
|
is particulary important for chained oggs. Initially, a new group is created in
|
|
the 'building' state. All new streams will be added to the building group until
|
|
no-more-pads is signaled or one of the preroll queues overflows. When this happens,
|
|
the group is commited to a list of groups ready for playback. PlaybaseBin will then
|
|
attach a padprobe to each stream to figure out when it finished. It will remove
|
|
the current group and install the next playable group, then.
|
|
|
|
Before going to the PLAYING state, it is possible to connect a custom element to
|
|
each of the streams. To do that, you have to add the element to the bin and then
|
|
connect the pad(s) from the stream(s). You do not have to add the elements in
|
|
a thread, the bin will take care of then when it's needed. You are allowed to use
|
|
threads inside the elements, of course.
|
|
The bin tries to be smart and doesn't add a queue when there is only one possible
|
|
stream.
|
|
|
|
|
|
TODO
|
|
- reuse, cleanup in ready state
|
|
- when the first pad is closed, it's possible that another dynamic element is
|
|
added somewhere so that we need a queue for the first pad as well.
|
|
|
|
playbin:
|
|
|
|
Extends playbasebin, sets up default audiosink and videosink for first audio/video
|
|
stream detected. implements seeking and querying on the configured sinks.
|
|
|
|
It also waits for new notifications from playbasebin about any new groups that are
|
|
becomming active. It then disconnects the sinks and reconnects them to the new
|
|
pads in the group.
|
|
|
|
TODO
|
|
- reuse, refcounting, cleanup in READY state
|
|
- be smarter about replugging the sinks instead of removing them and readding them.
|
|
- Do not crap out when the audio device is in use.
|
|
|
|
general
|
|
|
|
TODO
|
|
- playlist support. maybe use a playlist bin that streams the contents of the
|
|
playlist on a pad, interleaved with new_media events. Also add a tuner
|
|
interface while we're at it.
|
|
- plug the many memleaks.
|
|
|