Create a new step event. The purpose of the step event is to instruct a sink to skip amount (expressed in format) of media. It can be used to implement stepping through the video frame by frame or for doing fast trick modes.
A rate of <= 0.0 is not allowed. Pause the pipeline, for the effect of rate = 0.0 or first reverse the direction of playback using a seek event to get the same effect as rate < 0.0.
The flush flag will clear any pending data in the pipeline before starting the step operation.
The intermediate flag instructs the pipeline that this step operation is part of a larger step operation.