KsStreamPointerAdvanceOffsets function (ks.h)

Article
03/15/2022

The KsStreamPointerAdvanceOffsets function advances the offsets of StreamPointer.

Syntax

KSDDKAPI NTSTATUS KsStreamPointerAdvanceOffsets(
  [in] PKSSTREAM_POINTER StreamPointer,
  [in] ULONG             InUsed,
  [in] ULONG             OutUsed,
  [in] BOOLEAN           Eject
);

Parameters

[in] StreamPointer

A pointer to a KSSTREAM_POINTER structure representing the stream pointer for which to advance the offsets. StreamPointer should be in the locked state when this function is called.

[in] InUsed

The number of bytes to advance the input pointer of this stream pointer.

(StreamPointer -> OffsetIn)

[in] OutUsed

The number of bytes to advance the output pointer of this stream pointer

(StreamPointer -> OffsetOut)

[in] Eject

This parameter indicates whether the stream pointer should be advanced to the next data frame If this parameter is set to TRUE, AVStream advances the stream pointer regardless of whether advancing the offsets causes the stream pointer to point to the end of a frame.

Return value

KsStreamPointerAdvanceOffsets returns STATUS_SUCCESS on success. Returns STATUS_DEVICE_NOT_READY if either StreamPointer was not locked at call-time or that the stream pointer could not be locked after advancement.

Remarks

AVStream updates the in and out data pointers and other related fields by the requested values. If advancing the offsets results in zero bytes remaining in the current frame, AVStream advances the stream pointer to the next data frame and relocks it.

It is the responsibility of the minidriver to verify that StreamPointer is locked before calling KsStreamPointerAdvanceOffsets. Also, a single advancement cannot advance a stream pointer further than the beginning of the next frame in the queue. Thus, minidrivers should not attempt to advance offsets by a value greater than StreamPointer -> Offset*.Remaining.

Also see Stream Pointers.

Requirements

Requirement	Value
Minimum supported client	Available in Microsoft Windows XP and later operating systems and DirectX 8.0 and later DirectX versions.
Target Platform	Universal
Header	ks.h (include Ks.h)
Library	Ks.lib
IRQL	<=DISPATCH_LEVEL