AVEncVideoHeaderDropFrame property

[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 It has been superseded by MediaPlayer, IMFMediaEngine, and Audio/Video Capture in Media Foundation.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.]

Specifies the value of drop-frame flag in the group of pictures (GOP) header.

This property is read/write.

Data type

UINT32 (VT_UI4)

Property GUID

CODECAPI_AVEncVideoHeaderDropFrame

Property value

The value of this property can be 0 or 1.

Remarks

Drop-frame mode is used in NTSC video to correct the discrepancy between the video, which is 29.97 frames per second, and the time code display, which is 30 frames per second. In drop-frame mode, frame numbers 00 and 01 are skipped at the start of each minute, except for minutes that are even multiples of ten (00, 10, 20, and so forth). Only the frame numbers in the time code are dropped; no actual frames are dropped.

Requirements

See also

Codec API Properties

ICodecAPI Interface