The initial offset to use internally when outputting content (in nanoseconds, but in the time coordinates of the internal content).
For example, for a #GESVideoUriSource that references some media file, the "internal content" is the media file data, and the in-point would correspond to some timestamp in the media file. When playing the timeline, and when the element is first reached at timeline-time #GESTimelineElement:start, it will begin outputting the data from the timestamp in-point onwards, until it reaches the end of its #GESTimelineElement:duration in the timeline.
For elements that have no internal content, this should be kept as 0.
The full duration of internal content that is available (a time difference in nanoseconds using the time coordinates of the internal content).
This will act as a cap on the #GESTimelineElement:in-point of the element (which is in the same time coordinates), and will sometimes be used to limit the #GESTimelineElement:duration of the element in the timeline.
For example, for a #GESVideoUriSource that references some media file, this would be the length of the media file.
For elements that have no internal content, or whose content is indefinite, this should be kept as #GST_CLOCK_TIME_NONE.
The name of the element. This should be unique within its timeline.
The parent container of the element.
The priority of the element.
Whether the element should be serialized.
The starting position of the element in the timeline (in nanoseconds and in the time coordinates of the timeline). For example, for a source element, this would determine the time at which it should start outputting its internal content. For an operation element, this would determine the time at which it should start applying its effect to any source content.
The timeline that the element lies within.
The duration that the element is in effect for in the timeline (a time difference in nanoseconds using the time coordinates of the timeline). For example, for a source element, this would determine for how long it should output its internal content for. For an operation element, this would determine for how long its effect should be applied to any source content.