docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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Seeking
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-------
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Seeking in GStreamer means configuring the pipeline for playback of the
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2010-01-19 15:39:38 +00:00
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media between a certain start and stop time, called the playback segment.
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By default a pipeline will play from position 0 to the total duration of the
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media at a rate of 1.0.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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2008-10-13 17:19:25 +00:00
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A seek is performed by sending a seek event to the sink elements of a
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pipeline. Sending the seek event to a bin will by default forward
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the event to all sinks in the bin.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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2008-10-13 17:19:25 +00:00
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When performing a seek, the start and stop values of the segment can be
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specified as absoulte positions or relative to the currently configured
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playback segment. Note that it is not possible to seek relative to the current
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2010-01-19 15:39:38 +00:00
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playback position. To seek relative to the current playback position, one must
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query the position first and then perform an absolute seek to the desired
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position.
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2008-10-13 17:19:25 +00:00
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Feedback of the seek operation can be immediatly using the GST_SEEK_FLAG_FLUSH
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flag. With this flag, all pending data in the pipeline is discarded and playback
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starts from the new position immediatly.
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When the FLUSH flag is not set, the seek will be queued and executed as
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soon as possible, which might be after all queues are emptied.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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Seeking can be performed in different formats such as time, frames
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or samples.
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2008-10-13 17:19:25 +00:00
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The seeking can be performed to a nearby key unit or to the exact
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(estimated) unit in the media (GST_SEEK_FLAG_KEY_UNIT).
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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2008-10-13 17:19:25 +00:00
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The seeking can be performed by using an estimated target position or in an
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accurate way (GST_SEEK_FLAG_ACCURATE). For some formats this can result in
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having to scan the complete file in order to accurately find the target unit.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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Non segment seeking will make the pipeline emit EOS when the configured
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2005-11-03 14:22:44 +00:00
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segment has been played.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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2008-10-13 17:19:25 +00:00
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Segment seeking (using the GST_SEEK_FLAG_SEGMENT) will not emit an EOS at
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the end of the playback segment but will post a SEGMENT_DONE message on the
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bus. This message is posted by the element driving the playback in the
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pipeline, typically a demuxer. After receiving the message, the application
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can reconnect the pipeline or issue other seek events in the pipeline.
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Since the message is posted as early as possible in the pipeline, the
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application has some time to issue a new seek to make the transition seamless.
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Typically the allowed delay is defined by the buffer sizes of the sinks as well
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as the size of any queues in the pipeline.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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docs/design/part-seeking.txt: Some small additions.
Original commit message from CVS:
* docs/design/part-seeking.txt:
Some small additions.
* gst/base/gstbasesink.c: (gst_base_sink_handle_object),
(gst_base_sink_get_times), (gst_base_sink_do_sync),
(gst_base_sink_activate_push), (gst_base_sink_activate_pull):
* gst/base/gstbasesink.h:
discont values are gint64, handle the math correctly.
* gst/base/gstbasesrc.c: (gst_base_src_loop):
Make the basesrc report error if the source pad is not linked.
* gst/gstqueue.c: (gst_queue_link_src), (gst_queue_chain),
(gst_queue_loop), (gst_queue_handle_src_query),
(gst_queue_src_activate_push):
Make queue collect data even if the srcpad is not linked.
Start pushing out data as soon as it is linked.
* gst/gstutils.c: (gst_element_unlink), (gst_flow_get_name):
* gst/gstutils.h:
Added gst_flow_get_name() to ease error reporting.
2005-07-21 17:22:13 +00:00
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The seek can also change the playback speed of the configured segment.
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A speed of 1.0 is normal speed, 2.0 is double speed. Negative values
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mean backward playback.
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2008-10-13 17:19:25 +00:00
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When performing a seek with a playback rate different from 1.0, the
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GST_SEEK_FLAG_SKIP flag can be used to instruct decoders and demuxers that they
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are allowed to skip decoding. This can be useful when resource consumption is
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more important than accurately producing all frames.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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2010-01-19 15:39:38 +00:00
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Seeking in push based elements
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------------------------------
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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Generating seeking events
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-------------------------
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2008-10-13 17:19:25 +00:00
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A seek event is created with gst_event_new_seek ().
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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The different kinds of seeking methods and their internal workings are
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described below.
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FLUSH seeking
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-------------
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This is the most common way of performing a seek in a playback application.
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The application issues a seek on the pipeline and the new media is immediatly
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played after the seek calls returns.
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seeking without FLUSH
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---------------------
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This seek type is typically performed after issuing segment seeks to finish
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the playback of the pipeline.
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2006-03-13 10:32:26 +00:00
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Performing a non-flushing seek in a PAUSED pipeline blocks until the pipeline
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is set to playing again since all data passing is blocked in the prerolled
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sinks.
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docs/design/: Some more docs in the works.
Original commit message from CVS:
* docs/design/part-dynamic.txt:
* docs/design/part-events.txt:
* docs/design/part-seeking.txt:
Some more docs in the works.
* gst/base/gstbasetransform.c: (gst_base_transform_transform_caps),
(gst_base_transform_getcaps), (gst_base_transform_configure_caps),
(gst_base_transform_setcaps), (gst_base_transform_get_size),
(gst_base_transform_buffer_alloc), (gst_base_transform_event),
(gst_base_transform_handle_buffer),
(gst_base_transform_sink_activate_push),
(gst_base_transform_src_activate_pull),
(gst_base_transform_set_passthrough),
(gst_base_transform_is_passthrough):
Refcounting fixes.
* gst/gstbus.c: (gst_bus_source_dispatch), (gst_bus_poll):
Cleanups.
* gst/gstevent.c: (gst_event_finalize):
Set SRC to NULL.
* gst/gstutils.c: (gst_element_unlink),
(gst_pad_get_parent_element), (gst_pad_proxy_getcaps),
(gst_pad_proxy_setcaps):
* gst/gstutils.h:
Add _get_parent_element() to get a pads parent as an element.
2005-07-18 08:28:48 +00:00
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segment seeking with FLUSH
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--------------------------
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This seek is typically performed when starting seamless looping.
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segment seeking without FLUSH
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-----------------------------
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This seek is typically performed when continuing seamless looping.
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