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CMediaType.AllocFormatBuffer method

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[The feature associated with this page, DirectShow, is a legacy feature. It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation. Those features have been optimized for Windows 10 and Windows 11. Microsoft strongly recommends that new code use MediaPlayer, IMFMediaEngine and Audio/Video Capture in Media Foundation instead of DirectShow, when possible. Microsoft suggests that existing code that uses the legacy APIs be rewritten to use the new APIs if possible.]

The AllocFormatBuffer method allocates memory for the format block.

Syntax

BYTE* AllocFormatBuffer(
   ULONG length
);

Parameters

length

Size required for the format block, in bytes.

Return value

Returns a pointer to the new block if successful. Otherwise, returns NULL.

Remarks

If the method successfully allocates a new format block, it frees the existing format block. If the allocation fails, the method leaves the existing format block.

The method updates the cbFormat and pbFormat members of the AM_MEDIA_TYPE structure.

Requirements

Requirement Value
Header
Mtype.h (include Streams.h)
Library
Strmbase.lib (retail builds);
Strmbasd.lib (debug builds)

See also

CMediaType Class