Segment

This helper structure holds the relevant values for tracking the region of interest in a media file, called a segment.

The structure can be used for two purposes:

performing seeks (handling seek events)
tracking playback regions (handling newsegment events)

The segment is usually configured by the application with a seek event which is propagated upstream and eventually handled by an element that performs the seek.

The configured segment is then propagated back downstream with a newsegment event. This information is then used to clip media to the segment boundaries.

A segment structure is initialized with gst.segment.Segment.init_, which takes a #GstFormat that will be used as the format of the segment values. The segment will be configured with a start value of 0 and a stop/duration of -1, which is undefined. The default rate and applied_rate is 1.0.

The public duration field contains the duration of the segment. When using the segment for seeking, the start and time members should normally be left to their default 0 value. The stop position is left to -1 unless explicitly configured to a different value after a seek event.

The current position in the segment should be set by changing the position member in the structure.

For elements that perform seeks, the current segment should be updated with the gst.segment.Segment.doSeek and the values from the seek event. This method will update all the segment fields. The position field will contain the new playback position. If the start_type was different from GST_SEEK_TYPE_NONE, playback continues from the position position, possibly with updated flags or rate.

For elements that want to use #GstSegment to track the playback region, update the segment fields with the information from the newsegment event. The gst.segment.Segment.clip method can be used to check and clip the media data to the segment boundaries.

For elements that want to synchronize to the pipeline clock, gst.segment.Segment.toRunningTime can be used to convert a timestamp to a value that can be used to synchronize to the clock. This function takes into account the base as well as any rate or applied_rate conversions.

For elements that need to perform operations on media data in stream_time, gst.segment.Segment.toStreamTime can be used to convert a timestamp and the segment info to stream time (which is always between 0 and the duration of the stream).

class Segment : Boxed {

this();

bool clip(gst.types.Format format, ulong start, ulong stop, ulong clipStart, ulong clipStop);

gst.segment.Segment copy();

void copyInto(gst.segment.Segment dest);

bool doSeek(double rate, gst.types.Format format, gst.types.SeekFlags flags, gst.types.SeekType startType, ulong start, gst.types.SeekType stopType, ulong stop, bool update);

void init_(gst.types.Format format);

bool isEqual(gst.segment.Segment s1);

bool offsetRunningTime(gst.types.Format format, long offset);

ulong positionFromRunningTime(gst.types.Format format, ulong runningTime);

int positionFromRunningTimeFull(gst.types.Format format, ulong runningTime, ulong position);

ulong positionFromStreamTime(gst.types.Format format, ulong streamTime);

int positionFromStreamTimeFull(gst.types.Format format, ulong streamTime, ulong position);

bool setRunningTime(gst.types.Format format, ulong runningTime);

ulong toPosition(gst.types.Format format, ulong runningTime);

ulong toRunningTime(gst.types.Format format, ulong position);

int toRunningTimeFull(gst.types.Format format, ulong position, ulong runningTime);

ulong toStreamTime(gst.types.Format format, ulong position);

int toStreamTimeFull(gst.types.Format format, ulong position, ulong streamTime);

}

Constructors

this this(): Allocate a new #GstSegment structure and initialize it using gst.segment.Segment.init_.

Members

Functions

clip bool clip(gst.types.Format format, ulong start, ulong stop, ulong clipStart, ulong clipStop): Clip the given start and stop values to the segment boundaries given in segment. start and stop are compared and clipped to segment start and stop values.
copy gst.segment.Segment copy(): Create a copy of given segment.
copyInto void copyInto(gst.segment.Segment dest): Copy the contents of src into dest.
doSeek bool doSeek(double rate, gst.types.Format format, gst.types.SeekFlags flags, gst.types.SeekType startType, ulong start, gst.types.SeekType stopType, ulong stop, bool update): Update the segment structure with the field values of a seek event (see gst.event.Event.newSeek).
init_ void init_(gst.types.Format format): The start/position fields are set to 0 and the stop/duration fields are set to -1 (unknown). The default rate of 1.0 and no flags are set.
isEqual bool isEqual(gst.segment.Segment s1): Checks for two segments being equal. Equality here is defined as perfect equality, including floating point values.
offsetRunningTime bool offsetRunningTime(gst.types.Format format, long offset): Adjust the values in segment so that offset is applied to all future running-time calculations.
positionFromRunningTime ulong positionFromRunningTime(gst.types.Format format, ulong runningTime): Convert running_time into a position in the segment so that gst.segment.Segment.toRunningTime with that position returns running_time.
positionFromRunningTimeFull int positionFromRunningTimeFull(gst.types.Format format, ulong runningTime, ulong position): Translate running_time to the segment position using the currently configured segment. Compared to gst.segment.Segment.positionFromRunningTime this function can return negative segment position.
positionFromStreamTime ulong positionFromStreamTime(gst.types.Format format, ulong streamTime): Convert stream_time into a position in the segment so that gst.segment.Segment.toStreamTime with that position returns stream_time.
positionFromStreamTimeFull int positionFromStreamTimeFull(gst.types.Format format, ulong streamTime, ulong position): Translate stream_time to the segment position using the currently configured segment. Compared to gst.segment.Segment.positionFromStreamTime this function can return negative segment position.
setRunningTime bool setRunningTime(gst.types.Format format, ulong runningTime): Adjust the start/stop and base values of segment such that the next valid buffer will be one with running_time.
toPosition ulong toPosition(gst.types.Format format, ulong runningTime): Convert running_time into a position in the segment so that gst.segment.Segment.toRunningTime with that position returns running_time.
toRunningTime ulong toRunningTime(gst.types.Format format, ulong position): Translate position to the total running time using the currently configured segment. Position is a value between segment start and stop time.
toRunningTimeFull int toRunningTimeFull(gst.types.Format format, ulong position, ulong runningTime): Translate position to the total running time using the currently configured segment. Compared to gst.segment.Segment.toRunningTime this function can return negative running-time.
toStreamTime ulong toStreamTime(gst.types.Format format, ulong position): Translate position to stream time using the currently configured segment. The position value must be between segment start and stop value.
toStreamTimeFull int toStreamTimeFull(gst.types.Format format, ulong position, ulong streamTime): Translate position to the total stream time using the currently configured segment. Compared to gst.segment.Segment.toStreamTime this function can return negative stream-time.

Inherited Members

From Boxed

cInstancePtr void* cInstancePtr;: Pointer to the C boxed value
getType GType getType(): Get the GType of this boxed type.
gType GType gType [@property getter]: Boxed GType property.
self Boxed self(): Convenience method to return this cast to a type. For use in D with statements.
copy_ void* copy_(): Make a copy of the wrapped C boxed data.
boxedCopy void* boxedCopy(void* cBoxed): Copy a C boxed value using g_boxed_copy.
boxedFree void boxedFree(void* cBoxed): Free a C boxed value using g_boxed_free.

gst segment classes

Segment