KSAC3_ALTERNATE_AUDIO structure

The KSAC3_ALTERNATE_AUDIO structure specifies whether the two mono channels in an AC-3-encoded stream should be interpreted as a stereo pair or as two independent program channels.

Syntax

typedef struct KSAC3_ALTERNATE_AUDIO {
  BOOL  fStereo;
  ULONG DualMode;
}  *PKSAC3_ALTERNATE_AUDIO;

Members

fStereo

Specifies whether the two mono channels should be interpreted as a stereo pair. If TRUE, the two mono channels are treated as a stereo pair. If FALSE, DualMode=0x03 causes the two mono channels to be mixed before being output by the decoder.

DualMode

When two independent channels of audio are encoded in the stream, this member specifies whether to use the audio track in channel 1, channel 2, or both. A value of 0x01 selects channel 1, 0x02 selects channel 2, and 0x03 selects both. Specify the value of this member as one of the following constants:

Constant name Value
KSAC3_ALTERNATE_AUDIO_1 0x01
KSAC3_ALTERNATE_AUDIO_2 0x02
KSAC3_ALTERNATE_AUDIO_BOTH 0x03

Remarks

This structure is used by the KSPROPERTY_AC3_ALTERNATE_AUDIO property.

For more information about the encoding of AC-3 program channels, see the AC-3 specification at the Dolby Laboratories website. The specification is titled Digital Audio Compression Standard (AC-3).

Requirements

   
Header ksmedia.h (include Ksmedia.h)

See Also

KSPROPERTY_AC3_ALTERNATE_AUDIO