avir::CImageResizerFilterStepINL< fptype, fptypeatom > Class Template Reference

#include <avir.h>

Inheritance diagram for avir::CImageResizerFilterStepINL< fptype, fptypeatom >:

Public Member Functions
void	calcScanlineBias (const fptype *p, const int SrcLen, fptype *const ElBiases) const
void	convertVtoH (const fptype *ip, fptype *op, const int SrcLen, const int SrcIncr) const
void	doFilter (const fptype *const Src, fptype *Dst, const int DstIncr) const
void	doResize (const fptype *SrcLine, fptype *DstLine, const int DstLineIncr, const fptype *const ElBiases, fptype *const ) const
void	doResize2 (const fptype *SrcLine, fptype *DstLine, const int DstLineIncr, const fptype *const ElBiases, fptype *const ) const
void	doUpsample (const fptype *const Src, fptype *const Dst) const
template<class Tin >
void	packScanline (const Tin *ip, fptype *const op0, const int l0) const
void	prepareInBuf (fptype *Src) const
void	unbiasScanline (fptype *p, int l, const fptype *const ElBiases) const

Static Public Member Functions
static void	applySRGBGamma (fptype *p, int l, const CImageResizerVars &Vars0)
template<class Tout >
static void	unpackScanline (const fptype *ip, Tout *op, int l, const CImageResizerVars &Vars0)

Additional Inherited Members
Public Attributes inherited from avir::CImageResizerFilterStep< fptype, fptypeatom >
double	DCGain
int	EdgePixelCount
CBuffer< fptype >	Flt
CDSPFracFilterBankLin< fptype > *	FltBank
int	FltLatency
CFltBuffer	FltOrig
int	InBuf
int	InElIncr
int	InLen
int	InPrefix
int	InSuffix
bool	IsUpsample
int	OutBuf
int	OutElIncr
int	OutLen
int	OutPrefix
int	OutSuffix
CBuffer< fptype >	PrefixDC
int	ResampleFactor
CRPosBuf *	RPosBuf
CBuffer< fptype >	SuffixDC
const CImageResizerVars *	Vars
Static Public Attributes inherited from avir::CImageResizerFilterStep< fptype, fptypeatom >
static const int	EdgePixelCountDef = 3

Detailed Description

template<class fptype, class fptypeatom>
class avir::CImageResizerFilterStepINL< fptype, fptypeatom >

Interleaved filtering steps implementation class.

This class implements scanline filtering functions in interleaved mode. This means that each pixel is processed independently, not in groups.

Template Parameters

fptype	Floating point type to use for storing pixel elements. SIMD types can be used: in this case each element may hold a whole pixel.
fptypeatom	The atomic type the "fptype" consists of.

Member Function Documentation

template<class fptype , class fptypeatom >

static void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::applySRGBGamma ( fptype *  p, int  l, const CImageResizerVars &  Vars0  )

static

Function applies Linear to sRGB gamma correction to the specified scanline.

Parameters

p	Scanline.
l	The number of pixels to de-linearize.
Vars0	Image resizing-related variables.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::calcScanlineBias	(	const fptype *	p,
		const int	SrcLen,
		fptype *const	ElBiases
	)		const

Function calculates scanline's DC gain for each channel, further used to "unbias" the scanline.

Parameters

	p	Source scanline.
	SrcLen	Source scanline's length.
[out]	ElBiases	Resuling biases.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::convertVtoH	(	const fptype *	ip,
		fptype *	op,
		const int	SrcLen,
		const int	SrcIncr
	)		const

Function converts vertical scanline to horizontal scanline. This function is called by the image resizer when image is resized vertically. This means that the vertical scanline is stored in the same format produced by the packScanline() and maintained by other filtering functions.

Parameters

ip	Input vertical scanline.
op	Output buffer (temporary buffer used during resizing).
SrcLen	The number of pixels in the input scanline, also used to calculate input buffer increment.
SrcIncr	Input buffer increment to the next vertical pixel.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::doFilter	(	const fptype *const	Src,
		fptype *	Dst,
		const int	DstIncr
	)		const

Function peforms scanline filtering with optional downsampling. Function makes use of the symmetry of the filter.

Parameters

Src	Source scanline buffer (length = this -> InLen). Source scanline increment will be equal to ElCount.
Dst	Destination scanline buffer.
DstIncr	Destination scanline buffer increment, used for horizontal or vertical scanline stepping.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::doResize	(	const fptype *	SrcLine,
		fptype *	DstLine,
		const int	DstLineIncr,
		const fptype *const	ElBiases,
		fptype *	const
	)		const

Function performs resizing of a single scanline. This function does not "know" about the length of the source scanline buffer. This buffer should be padded with enough pixels so that ( SrcPos - FilterLenD2 ) is always >= 0 and ( SrcPos + ( DstLineLen - 1 ) * k + FilterLenD2 + 1 ) does not exceed source scanline's buffer length. SrcLine's increment is assumed to be equal to ElCount.

Parameters

SrcLine	Source scanline buffer.
DstLine	Destination (resized) scanline buffer.
DstLineIncr	Destination scanline position increment, used for horizontal or vertical scanline stepping.
ElBiases	Bias values to add to the resulting scanline.
xx	Temporary buffer, of size FltBank -> getFilterLen(), must be aligned by fpclass :: fpalign.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::doResize2	(	const fptype *	SrcLine,
		fptype *	DstLine,
		const int	DstLineIncr,
		const fptype *const	ElBiases,
		fptype *	const
	)		const

Function performs resizing of a single scanline assuming that the input buffer consists of zero-padded elements (2X upsampling without filtering). Similar to the doResize() function otherwise.

Parameters

SrcLine	Source scanline buffer.
DstLine	Destination (resized) scanline buffer.
DstLineIncr	Destination scanline position increment, used for horizontal or vertical scanline stepping.
ElBiases	Bias values to add to the resulting scanline.
xx	Temporary buffer, of size FltBank -> getFilterLen(), must be aligned by fpclass :: fpalign.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::doUpsample	(	const fptype *const	Src,
		fptype *const	Dst
	)		const

Function peforms scanline upsampling with filtering.

Parameters

Src	Source scanline buffer (length = this -> InLen). Source scanline increment will be equal to ElCount.
Dst	Destination scanline buffer.

template<class fptype , class fptypeatom >

template<class Tin >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::packScanline	(	const Tin *	ip,
		fptype *const	op0,
		const int	l0
	)		const

Function performs "packing" of a scanline, and type conversion. Scanline, depending on the "fptype" can be potentially stored as a packed SIMD values having a certain atomic type. If required, the sRGB gamma correction is applied.

Parameters

ip	Input scanline.
op0	Output scanline.
l0	The number of pixels to "pack".

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::prepareInBuf

(

fptype *

Src

)

const

Function prepares input scanline buffer for *this filtering step. Left- and right-most pixels are replicated to make sure no buffer overrun happens. Such approach also allows to bypass any pointer range checks.

Parameters

Src	Source buffer.

template<class fptype , class fptypeatom >

void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::unbiasScanline	(	fptype *	p,
		int	l,
		const fptype *const	ElBiases
	)		const

Function applies "unbiasing" to the scanline, by subtracting the previously calculated bias (DC gain) values.

Parameters

p	Scanline.
l	Scanline's length.
ElBiases	Biases to subtract, for each channel.

template<class fptype , class fptypeatom >

template<class Tout >

static void avir::CImageResizerFilterStepINL< fptype, fptypeatom >::unpackScanline ( const fptype *  ip, Tout *  op, int  l, const CImageResizerVars &  Vars0  )

static

Function performs "unpacking" of a scanline and type conversion (truncation is used when floating point is converted to integer). Scanline, depending on the "fptype" can be potentially stored as a packed SIMD values having a certain atomic type. The unpacking function assumes that scanline is stored in the style produced by the packScanline() function.

Parameters

ip	Input scanline.
op	Output scanline.
l	The number of pixels to "unpack".
Vars0	Image resizing-related variables.