avir::CImageResizerDithererErrdINL< fptype > Class Template Reference

Image resizer's error-diffusion dithering class, interleaved mode. More...

#include <avir.h>

Inheritance diagram for avir::CImageResizerDithererErrdINL< fptype >:

Public Member Functions
void	dither (fptype *const ResScanline)
	Performs rounding and clipping operations, in-place.
void	init (const int aLen, const CImageResizerVars &aVars, const double aTrMul, const double aPkOut)
	Initializes the ditherer object.
Public Member Functions inherited from avir::CImageResizerDithererDefINL< fptype >
void	dither (fptype *const ResScanline) const
	Performs rounding and clipping operations, in-place.
void	init (const int aLen, const CImageResizerVars &aVars, const double aTrMul, const double aPkOut)
	Initializes the ditherer object.

Static Public Member Functions
static bool	isRecursive ()
	Returns true, if dithering is recursive relative to scanlines, meaning multi-threaded execution is not supported by this dithering method.
Static Public Member Functions inherited from avir::CImageResizerDithererDefINL< fptype >
static bool	isRecursive ()
	Returns true, if dithering is recursive relative to scanlines, meaning multi-threaded execution is not supported by this dithering method.

Protected Attributes
fptype *	ResScanlineDith
	Error diffusion buffer pointer which skips the first ElCount elements.
CBuffer< fptype >	ResScanlineDith0
	Error diffusion buffer.
Protected Attributes inherited from avir::CImageResizerDithererDefINL< fptype >
int	Len
	Scanline's length in pixels.
int	LenE
	= LenE * ElCount.
double	PkOut0
	Peak output value allowed.
double	TrMul0
	Bit-depth truncation multiplier.
const CImageResizerVars *	Vars
	Image resizing-related variables.

Detailed Description

template<typename fptype>
class avir::CImageResizerDithererErrdINL< fptype >

Image resizer's error-diffusion dithering class, interleaved mode.

This ditherer implements error-diffusion dithering which looks good, and whose results are compressed by PNG well. This implementation uses weighting coefficients obtained via machine optimization and visual evaluation.

Template Parameters

fptype

Floating point type to use for storing pixel data. SIMD types can be used.

Member Function Documentation

dither()

template<typename fptype>

void avir::CImageResizerDithererErrdINL< fptype >::dither

(

fptype *const

ResScanline

)

Performs rounding and clipping operations, in-place.

Parameters

[in,out]

ResScanline

The buffer containing the final scanline.

init()

template<typename fptype>

void avir::CImageResizerDithererErrdINL< fptype >::init	(	const int	aLen,
		const CImageResizerVars &	aVars,
		const double	aTrMul,
		const double	aPkOut )

Initializes the ditherer object.

Parameters

aLen	Scanline length in pixels to process.
aVars	Image resizing-related variables.
aTrMul	Bit-depth truncation multiplier. 1 - no additional truncation.
aPkOut	Peak output value allowed.

isRecursive()

template<typename fptype>

static bool avir::CImageResizerDithererErrdINL< fptype >::isRecursive ( )

static

Returns true, if dithering is recursive relative to scanlines, meaning multi-threaded execution is not supported by this dithering method.