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AM_SAMPLE2_PROPERTIES Structure

 
Microsoft DirectShow 9.0

AM_SAMPLE2_PROPERTIES Structure

The AM_SAMPLE2_PROPERTIES structure describes the properties of a media sample. The IMediaSample2 interface uses this structure.

Syntax

typedef struct tagAM_SAMPLE2_PROPERTIES {
    DWORD           cbData;
    DWORD           dwTypeSpecificFlags;
    DWORD           dwSampleFlags;
    LONG            lActual;
    REFERENCE_TIME  tStart;
    REFERENCE_TIME  tStop;
    DWORD           dwStreamId;
    AM_MEDIA_TYPE   *pMediaType;
    BYTE            *pbBuffer;
    LONG            cbBuffer;
} AM_SAMPLE2_PROPERTIES;

Members

cbData

Length of property data, in bytes. This structure member is for extensibility.

dwTypeSpecificFlags

Type-specific flags. Flags are defined separately for each media type. The default value is AM_VIDEO_FLAG_INTERLEAVED_FRAME (zero). The following flags are used for video streams. They are defined in the header file dvdmedia.h.

Flag Value Description
AM_VIDEO_FLAG_FIELD_MASK 0x0003 Use this mask to check whether the sample is a field or a frame.
AM_VIDEO_FLAG_INTERLEAVED_FRAME 0x0000 The sample is a frame. (Use the AM_VIDEO_FLAG_FIELD_MASK bitmask to test for this value.)
AM_VIDEO_FLAG_FIELD1 0x0001 The sample is field 1. (Use the AM_VIDEO_FLAG_FIELD_MASK bitmask to test for this value.)
AM_VIDEO_FLAG_FIELD2 0x0002 The sample is the field 2. (Use the AM_VIDEO_FLAG_FIELD_MASK bitmask to test for this value.)
AM_VIDEO_FLAG_FIELD1FIRST 0x0004 If this flag is set, display field 1 first. Otherwise, display field 2 first. (Applies only when there are two fields per sample.)
AM_VIDEO_FLAG_WEAVE 0x0008 If this flag is set, use weave mode (that is, do not deinterlace the sample). Otherwise, use bob mode. This flag applies only when there are two fields per sample.
AM_VIDEO_FLAG_REPEAT_FIELD 0x0040 If this flag is set, display the first field again after displaying the second field. (Applies only when there are two fields per sample.)
AM_ReverseBlockStart 0x2 Signals the start of a VOBU during reverse playback of DVD video.  For more information, see DVD Playback Enhancements in Windows Vista.
AM_ReverseBlockEnd 0x4 Signals the end of a VOBU during reverse playback of DVD video. The DVD Navigator sets this flag on an empty sample to signal the end of a VOBU. For more information, see DVD Playback Enhancements in Windows Vista.

Other flags are defined but not currently used. See dvdmedia.h.

dwSampleFlags

Bitwise combination of flags the AM_SAMPLE_PROPERTY_FLAGS enumerated data type. Undefined bits are reserved and must be zero.

lActual

Length of the valid data in the buffer.

tStart

Start time, if valid. The dwSampleFlags member specifies whether this member is valid.

tStop

Stop time, if valid. The dwSampleFlags member specifies whether this member is valid.

dwStreamId

Stream identifier. If the value is AM_STREAM_MEDIA, the stream contains media data. If the value is AM_STREAM_CONTROL, the stream contains control information. Applications can define values of 0x80000000 or greater for their own use. (See AM_SAMPLE_PROPERTY_FLAGS Enumeration.)

pMediaType

Pointer to an AM_MEDIA_TYPE structure that specifies the media type if the format has changed. If this format has not changed, this member is NULL.

pbBuffer

Pointer to the sample buffer.

cbBuffer

Size of the sample buffer, in bytes.

Requirements

  Header: Dshow.h.

See Also