Frame Stepping Property Set

Decoders that implement frame-accurate seeking under Microsoft® DirectShow® must implement the AM_KSPROPSETID_FrameStep property set, which is used in conjunction with the IVideoFrameStep interface. This property set consists of two properties. AM_PROPERTY_FRAMESTEP is used to pass the step commands and stepping-capability information, and AM_FRAMESTEP_STEP is used to specify the number of frames to step.