Declarations

function ApplyCustomGamma(Color: TColor32; GammaTable: TGammaTable8Bit): TColor32; overload;
procedure ApplyCustomGamma(Color: PColor32Array; Length: Integer; GammaTable: TGammaTable8Bit); overload;
procedure ApplyCustomGamma(Bitmap: TBitmap32; GammaTable: TGammaTable8Bit); overload;
procedure ApplyCustomGamma(Bitmap: TBitmap32; Gamma: Double); overload;

Overload Details

Overload 1

function ApplyCustomGamma(Color: TColor32; GammaTable: TGammaTable8Bit): TColor32; overload;

Applies a custom 256-byte lookup table to the Red, Green, and Blue channels of a single TColor32 value.

Parameter	Type	Description
Color	TColor32	Input 32-bit ARGB color value.
GammaTable	TGammaTable8Bit	Custom 256-byte gamma lookup table array.

Type	Description
TColor32	Transformed color value with original alpha channel preserved.

Overload 2

procedure ApplyCustomGamma(Color: PColor32Array; Length: Integer; GammaTable: TGammaTable8Bit); overload;

Applies a custom 256-byte lookup table in-place to a contiguous buffer array of TColor32 pixels.

Parameter	Type	Description
Color	PColor32Array	Pointer to contiguous array of TColor32 pixels.
Length	Integer	Number of pixels to process in the array.
GammaTable	TGammaTable8Bit	Custom 256-byte gamma lookup table array.

Overload 3

procedure ApplyCustomGamma(Bitmap: TBitmap32; GammaTable: TGammaTable8Bit); overload;

Applies a custom 256-byte lookup table in-place to all pixels in a TBitmap32.

Parameter	Type	Description
Bitmap	TBitmap32	Target bitmap to transform in-place.
GammaTable	TGammaTable8Bit	Custom 256-byte gamma lookup table array.

Overload 4

procedure ApplyCustomGamma(Bitmap: TBitmap32; Gamma: Double); overload;

Applies a specified power-law gamma exponent in-place to all pixels in a TBitmap32.

Parameter	Type	Description
Bitmap	TBitmap32	Target bitmap to transform in-place.
Gamma	Double	Power-law gamma exponent to apply.

Description

ApplyCustomGamma transforms color channels using a custom TGammaTable8Bit lookup table or floating-point power-law exponent Gamma.

The 2-parameter bitmap overload ApplyCustomGamma(Bitmap, Gamma) checks whether GAMMA_VALUE matches Gamma. If GAMMA_VALUE = Gamma, it reuses GAMMA_ENCODING_TABLE directly for optimal performance; otherwise, it generates a temporary table via SetGamma and applies it to the bitmap.

Example

var
  CustomTable: TGammaTable8Bit;
begin
  SetGamma(2.2, CustomTable);
  ApplyCustomGamma(MyBitmap, CustomTable);

  // Or directly pass a gamma exponent
  ApplyCustomGamma(MyBitmap, 1.8);
end;

See also

• ApplyGamma
• ApplyInvGamma
• TGammaTable8Bit