IMFAttributes::GetBlob Method

Retrieves a byte array associated with a key. This method copies the array into a caller-allocated buffer.

Syntax

public:
HRESULT GetBlob(
         REFGUID guidKey,
         UINT8 *pBuf,
         UINT32 cbBufSize,
         UINT32 *pcbBlobSize
)

Parameters

guidKey
Type: REFGUID

[in]

GUID that identifies which value to retrieve. The attribute type must be MF_ATTRIBUTE_BLOB.

pBuf
Type: UINT8 *

[out]

Pointer to a buffer allocated by the caller. If the key is found and the value is a byte array, the method copies the array into this buffer. To find the required size of the buffer, call IMFAttributes::GetBlobSize.

cbBufSize
Type: UINT32

The size of the pBuf buffer, in bytes.

pcbBlobSize
Type: UINT32 *

[in, out, optional]

Receives the size of the byte array. This parameter can be NULL.

Return value

Type: HRESULT

The method returns an HRESULT. Possible values include, but are not limited to, those in the following table.

Return codes

Return code	Description
S_OK	The method succeeded.
E_NOT_SUFFICIENT_BUFFER	The buffer is not large enough to the array.
MF_E_ATTRIBUTENOTFOUND	The specified key was not found.
MF_E_INVALIDTYPE	The attribute value is not a byte array.

Refer to Media Foundation return codes.

Remarks

You can also use the IMFAttributes::GetAllocatedBlob method, which allocates the buffer to hold the byte array.

Requirements

Header: Declared in mfobjects.h (include mfidl.h).

Library: Use Mfuuid.lib.