Microsoft DirectX 8.0

IMediaPropertyBag Interface

The IMediaPropertyBag interface is exposed by the media property bag. The media property bag is a specialized version of the standard COM property bag, designed for setting and retrieving INFO and DISP chunks in Audio-Video Interleaved (AVI) files.

An INFO chunk contains meta-information about a file, such as author and copyright information. A DISP chunk contains data in Clipboard format. For more information, refer to the resource interchange file format (RIFF) specification.

The media property bag stores the chunks as name/value pairs, as follows:

This interface inherits the IPropertyBag interface. Use this interface with the IPersistMediaPropertyBag interface to retrieve INFO and DISP chunks from an AVI file.

Methods in Vtable Order

IUnknown methodsDescription
QueryInterface Retrieves pointers to supported interfaces.
AddRef Increments the reference count.
Release Decrements the reference count.
IMediaPropertyBag methodsDescription
EnumProperty Retrieves a property/value pair.

IMediaPropertyBag::EnumProperty

IMediaPropertyBag Interface

Retrieves a property/value pair.

Syntax

HRESULT EnumProperty(
    ULONG iProperty,
    VARIANT *pvarPropertyName,
    VARIANT *pvarPropertyValue
);

Parameters

iProperty
[in] Index value of the pair.
pvarPropertyName
[in, out] Pointer to a VARIANT that receives the property's name.
pvarPropertyValue
[in, out] Pointer to a VARIANT that receives the property's value.

Return Value

Returns an HRESULT value. Possible values include the following:

S_OKSuccess.
E_INVALIDARGInvalid argument.
E_OUTOFMEMORYInsufficient memory.
E_POINTERNULL pointer argument.
HRESULT_FROM_WIN32(ERROR_NO_MORE_ITEMS)Index out of range.

Remarks

The name is always a string. Set the variant type of the pvarPropertyName parameter to VT_EMPTY or VT_BSTR before calling this method.

The value can be a string (for INFO chunks) or an array of bytes (for DISP chunks). Set the variant type of the pvarPropertyName parameter to VT_EMPTY, VT_BSTR, or (VT_ARRAY | VT_UI1).