Microsoft DirectX 8.0 |
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.
Syntax
typedef enum { AM_PROPERTY_FRAMESTEP_STEP = 0x01, AM_PROPERTY_FRAMESTEP_CANCEL = 0x02, AM_PROPERTY_FRAMESTEP_CANSTEP = 0x03, AM_PROPERTY_FRAMESTEP_CANSTEPMULTIPLE = 0x04 } AM_PROPERTY_FRAMESTEP;Members
- AM_PROPERTY_FRAMESTEP_STEP
- Instructs the decoder to begin a step operation.
- AM_PROPERTY_FRAMESTEP_CANCEL
- Instructs the decoder to cancel the current step operation.
- AM_PROPERTY_FRAMESTEP_CANSTEP
- The decoder returns S_OK on this instruction to indicate that it can perform frame stepping, S_FALSE otherwise.
- AM_PROPERTY_FRAMESTEP_CANSTEPMULTIPLE
- The decoder returns S_OK on this instruction to indicate that it can step multiple frames at a time, S_FALSE otherwise.
typedef struct _AM_FRAMESTEP_STEP { DWORD dwFramesToStep; } AM_FRAMESTEP_STEP;AM_FRAMESTEP_STEP Members
- dwFramesToStep
- DWORD value specifying to the decoder the number of frames to step. Must be at least 1. If greater than one, this instruction means to skip (n - 1) frames and show the nth.