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DMO_MEDIA_TYPE

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This structure describes the format of the data used by a stream in a DirectX DMO. This structure is identical to the Microsoft DirectShow AM_MEDIA_TYPE structure.

typedef struct _DMOMediaType {
  GUID majortype;
  GUID subtype;
  BOOL bFixedSizeSamples;
  BOOL bTemporalCompression;
  ULONG lSampleSize;
  GUID formattype;
  IUnknown* pUnk;
  ULONG cbFormat;
  [size_is(cbFormat)] BYTE* pbFormat;
 } DMO_MEDIA_TYPE;

Members

  • majortype
    A GUID identifying the stream's major media type. This must be one of the DMO Media Types.
  • subtype
    Subtype GUID of the stream.
  • bFixedSizeSamples
    If TRUE, samples are of a fixed size. This field is informational only. For audio, it is generally set to TRUE. For video, it is usually TRUE for uncompressed video and FALSE for compressed video.
  • bTemporalCompression
    If TRUE, samples are compressed using temporal (interframe) compression. A value of TRUE indicates that not all frames are key frames. This field is informational only.
  • lSampleSize
    Size of the sample, in bytes. For compressed data, the value can be zero.
  • formattype
    GUID specifying the format type. The pbFormat member points to the corresponding format structure. Format types include the following.
    Format type Format structure
    FORMAT_None No format type
    FORMAT_MPEGVideo MPEG1VIDEOINFO
    FORMAT_MPEG2Video MPEG2VIDEOINFO
    FORMAT_VideoInfo VIDEOINFOHEADER
    FORMAT_VideoInfo2 VIDEOINFOHEADER2
    FORMAT_WaveFormatEx WAVEFORMATEX
  • pUnk
    Not used.
  • cbFormat
    Size of the format block of the media type.
  • pbFormat
    Pointer to the format structure. The structure type is specified by the formattype member. The format structure must be present, unless formattype is GUID_NULL or FORMAT_None.

Remarks

The bFixedSizeSamples, bTemporalCompression, and lSampleSize members are for compatibility with DirectShow. Other DMO clients are not required to use them.

Requirements

OS Versions: Windows CE .NET 4.1 and later.
Header: Dmo.h.
Link Library: Dmoguid.lib.

See Also

Structures | AM_MEDIA_TYPE | MPEG1VIDEOINFO | MPEG2VIDEOINFO | VIDEOINFOHEADER | VIDEOINFOHEADER2 | WAVEFORMATEX | Media Types

Last updated on Wednesday, April 13, 2005

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