MFSampleExtension_DerivedFromTopField attribute

Specifies whether a deinterlaced video frame was derived from the upper field or the lower field. This attribute applies to media samples.

Data type

BOOL stored as UINT32

Syntax

GUID MFSampleExtension_DerivedFromTopField = {0x6852465a,0xae1c,0x4553,{0x8e,0x9b,0xc3,0x42,0x0f,0xcb,0x16,0x37} }  

Get/set

To get this attribute, call IMFAttributes::GetUINT32

To set this attribute, call IMFAttributes::SetUINT32

Applies to

IMFSample:

Remarks

This attribute is valid for deinterlaced samples only. Set this attribute if the frame was deinterlaced by interpolating one of the fields.

If the value is TRUE, the lower field was interpolated from the upper field. If the value is FALSE, the upper field was interpolated from the lower field.

If the attribute is not set, the frame has not been deinterlaced. The frame is either a true progressive frame, or it is an interlaced frame.

This attribute is informational. A software deinterlacer could set this attribute. If this attribute is set, it provides a hint that you can recover the original field by dropping the interpolated scan lines. For example, if the attribute is TRUE, you can recover the original upper field by dropping the interpolated lower field.

The GUID constant for this attribute is exported from mfuuid.lib.

Requirements

Header: Declared in mfapi.h.