Gst.Query.prototype.set_segment

function set_segment(rate:Number, format:Gst.Format, start_value:Number, stop_value:Number):void {
    // Gjs wrapper for gst_query_set_segment()
}

Answer a segment query by setting the requested values. The normal playback segment of a pipeline is 0 to duration at the default rate of 1.0. If a seek was performed on the pipeline to play a different segment, this query will return the range specified in the last seek.

start_value and stop_value will respectively contain the configured playback range start and stop values expressed in format. The values are always between 0 and the duration of the media and start_value <= stop_value. rate will contain the playback rate. For negative rates, playback will actually happen from stop_value to start_value.