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IAMExtTransport::GetCapability

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Microsoft DirectShow 9.0

IAMExtTransport::GetCapability

The GetCapability method retrieves the general capabilities of the transport.

Syntax

  HRESULT GetCapability(
  long Capability,
  long *pValue,
  double *pdblValue
);

Parameters

Capability

[in]  Specifies the capability to check. See Remarks for more information.

pValue

[out]  Pointer to a variable that receives a long integer. See Remarks for more information.

pdblValue

[out]  Pointer to a variable that receives a double. See Remarks for more information.

Return Values

When this method succeeds, it returns S_OK. Otherwise it returns an HRESULT error code.

Remarks

The Capability parameter is a flag that specifies which capability to check. The method returns the result either in the pValue parameter or in the pdblValue parameter, depending on the capability flag.

For the following flags, the method returns the value OATRUE or OAFALSE in the pValue parameter. The value OATRUE indicates that the capability is present, while the value OAFALSE indicates it is absent.

Capability Flag Description
ED_TRANSCAP_CAN_ASSEMBLE Transport can use assemble record mode (record new tracks that link seamlessly to the control track from the previously recorded segment).
ED_TRANSCAP_CAN_BUMP_PLAY Transport can synchronize by varying speed.
ED_TRANSCAP_CAN_DELAY_AUDIO_IN Transport can perform delayed-in audio edits.
ED_TRANSCAP_CAN_DELAY_AUDIO_OUT Transport can perform delayed-out audio edits.
ED_TRANSCAP_CAN_DELAY_VIDEO_IN Transport can perform delayed-in video edits.
ED_TRANSCAP_CAN_DELAY_VIDEO_OUT Transport can perform delayed-out video edits.
ED_TRANSCAP_CAN_DETECT_LENGTH Transport can detect the length of the media.
ED_TRANSCAP_CAN_EJECT Transport can eject the media.
ED_TRANSCAP_CAN_FREEZE Transport can freeze/pause.
ED_TRANSCAP_CAN_INSERT Transport can use insert record mode (record individual tracks while locked to a prerecorded control track).
ED_TRANSCAP_CAN_PLAY_BACKWARDS Transport can play backward.
ED_TRANSCAP_CAN_SET_EE Transport can show the device's input on its output.
ED_TRANSCAP_CAN_SET_PB Transport can show media playback on its output.
ED_TRANSCAP_FIELD_STEP Transport responds to a frame advance command by advancing one field.
ED_TRANSCAP_HAS_CLOCK Device has a clock.
ED_TRANSCAP_HAS_DT Device has dynamic tracking.
ED_TRANSCAP_HAS_TIMER Device has a timer.
ED_TRANSCAP_HAS_TUNER Device has a tuner.
ED_TRANSCAP_IS_MASTER Device is the master clock for synchronizing.
ED_TRANSCAP_MULTIPLE_EDITS Device supports multiple edit events.
ED_TRANSCAP_NEEDS_CUEING Device must be cued before it performs an edit.
ED_TRANSCAP_NEEDS_TBC Device needs to be calibrated.

For the following flags, the method returns a numeric value in the pValue parameter.

Capability Flag Returned Value
ED_TRANSCAP_LTC_TRACK Returns the track number of the LTC timecode track, or ED_ALL if there is no dedicated timecode track.
ED_TRANSCAP_NUM_AUDIO_TRACKS Returns the number of audio tracks.

For the following flags, the method returns a value in the pdblValue parameter.

Capability Flag Returned Value
ED_TRANSCAP_FWD_SHUTTLE_MAX Maximum forward speed in shuttle mode, as a multiple of play speed.
ED_TRANSCAP_FWD_SHUTTLE_MIN Minimum forward speed in shuttle mode, as a multiple of play speed.
ED_TRANSCAP_FWD_VARIABLE_MAX Maximum forward speed, as a multiple of play speed.
ED_TRANSCAP_FWD_VARIABLE_MIN Minimum forward speed, as a multiple of play speed.
ED_TRANSCAP_REV_SHUTTLE_MAX Maximum reverse speed in shuttle mode, as a multiple of play speed.
ED_TRANSCAP_REV_SHUTTLE_MIN Minimum reverse speed in shuttle mode, as a multiple of play speed.
ED_TRANSCAP_REV_VARIABLE_MAX Maximum reverse speed, as a multiple of play speed.
ED_TRANSCAP_REV_VARIABLE_MIN Minimum reverse speed, as a multiple of play speed.

DV Implementation

MSDV does not support this method. It returns E_NOTIMPL.

Requirements

Header: Declared in Strmif.h; include Dshow.h.

Library: Use Strmiids.lib.

See Also