Gdk.FrameTimings

Fields

None

Details

class Gdk.FrameTimings

A Gdk.FrameTimings object holds timing information for a single frame of the application’s displays. To retrieve Gdk.FrameTimings objects, use Gdk.FrameClock.get_timings() or Gdk.FrameClock.get_current_timings(). The information in Gdk.FrameTimings is useful for precise synchronization of video with the event or audio streams, and for measuring quality metrics for the application’s display, such as latency and jitter.

get_complete()[source]
Returns:True if all information that will be available for the frame has been filled in.
Return type:bool

The timing information in a Gdk.FrameTimings is filled in incrementally as the frame as drawn and passed off to the window system for processing and display to the user. The accessor functions for Gdk.FrameTimings can return 0 to indicate an unavailable value for two reasons: either because the information is not yet available, or because it isn’t available at all. Once Gdk.FrameTimings.get_complete() returns True for a frame, you can be certain that no further values will become available and be stored in the Gdk.FrameTimings.

New in version 3.8.

get_frame_counter()[source]
Returns:the frame counter value for this frame
Return type:int

Gets the frame counter value of the Gdk.FrameClock when this this frame was drawn.

New in version 3.8.

get_frame_time()[source]
Returns:the frame time for the frame, in the timescale of GLib.get_monotonic_time()
Return type:int

Returns the frame time for the frame. This is the time value that is typically used to time animations for the frame. See Gdk.FrameClock.get_frame_time().

get_predicted_presentation_time()[source]
Returns:The predicted time at which the frame will be presented, in the timescale of GLib.get_monotonic_time(), or 0 if no predicted presentation time is available.
Return type:int

Gets the predicted time at which this frame will be displayed. Although no predicted time may be available, if one is available, it will be available while the frame is being generated, in contrast to Gdk.FrameTimings.get_presentation_time(), which is only available after the frame has been presented. In general, if you are simply animating, you should use Gdk.FrameClock.get_frame_time() rather than this function, but this function is useful for applications that want exact control over latency. For example, a movie player may want this information for Audio/Video synchronization.

New in version 3.8.

get_presentation_time()[source]
Returns:the time the frame was displayed to the user, in the timescale of GLib.get_monotonic_time(), or 0 if no presentation time is available. See Gdk.FrameTimings.get_complete()
Return type:int

Reurns the presentation time. This is the time at which the frame became visible to the user.

New in version 3.8.

get_refresh_interval()[source]
Returns:the refresh interval of the display, in microseconds, or 0 if the refresh interval is not available. See Gdk.FrameTimings.get_complete().
Return type:int

Gets the natural interval between presentation times for the display that this frame was displayed on. Frame presentation usually happens during the “vertical blanking interval”.

New in version 3.8.

ref()[source]
Returns:self
Return type:Gdk.FrameTimings

Increases the reference count of self.

New in version 3.8.

unref()[source]

Decreases the reference count of self. If self is no longer referenced, it will be freed.

New in version 3.8.