Vcl.Imaging.pngimage.TFilter

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Delphi

TFilter = (pfNone, pfSub, pfUp, pfAverage, pfPaeth);

C++

enum DECLSPEC_DENUM TFilter : unsigned char { pfNone, pfSub, pfUp, pfAverage, pfPaeth };

Properties

Type Visibility Source Unit Parent
enum public
Vcl.Imaging.pngimage.pas
Vcl.Imaging.pngimage.hpp
Vcl.Imaging.pngimage Vcl.Imaging.pngimage

Description

TFilter enumerates the possible filter algorithms for a png image.

TFilter enumerates the possible filter algorithms for a png image. A filter algorithm is used before compressing a png image. The main purpose of the filter algorithm is to prepare the image for optimal compression. The following table lists the possible values and their meaning.



Value Meaning

pfNone

No filter is applied; scan lines are stored directly.

pfSub

The Sub algorithm is used.

pfUp

The Up algorithm is used.

pfAverage

The Average algorithm is used.

pfPaeth

The Paeth algorithm is used.