CImageDisplay.CountPrefixBits method

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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 CountPrefixBits method calculates the number of zero bits at the start of a specified bit field.

Syntax

DWORD CountPrefixBits(
   const DWORD Field
);

Parameters

Field

Specifies a bit field as a DWORD value.

Return value

Returns the number of zero bits that occur before the first 1 bit, or 0x80000000 if all bits are zero.

Remarks

This method is useful for working with color masks in VIDEOINFO structures.

Requirements

See also

CImageDisplay Class