MP_ENVELOPE_SEGMENT structure (medparam.h)

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The MP_ENVELOPE_SEGMENT structure defines an envelope segment used by an envelope-following parameter.

Syntax

typedef struct _MP_ENVELOPE_SEGMENT {
  REFERENCE_TIME rtStart;
  REFERENCE_TIME rtEnd;
  MP_DATA        valStart;
  MP_DATA        valEnd;
  MP_CURVE_TYPE  iCurve;
  MP_FLAGS       flags;
} MP_ENVELOPE_SEGMENT;

Members

rtStart

Start time of the segment, relative to the time stamp on the first buffer, in 100-nanosecond units.

rtEnd

Stop time of the segment, relative to the time stamp on the first buffer, in 100-nanosecond units.

valStart

Initial value of the parameter, at the start of the segment.

valEnd

Final value of the parameter, at the end of the segment.

iCurve

Member of the MP_CURVE_TYPE enumerated type that specifies the curve followed by the parameter.

flags

Specifies one of the following flags.

Value	Meaning
MPF_ENVLP_STANDARD 0x0000	Use all the information provided with the envelope segment.
MPF_ENVLP_BEGIN_CURRENTVAL 0x0001	Ignore the specified start value. Start from the current value.
MPF_ENVLP_BEGIN_NEUTRALVAL 0x0002	Ignore the specified start value. Start from the neutral value. (See MP_PARAMINFO.)

Requirements

Requirement	Value
Header	medparam.h

See also

DMO Structures