AlphaComposer

The class AlphaComposer provides methods to alpha-overlay uchar or double arrays.

After initialisation you call the methods addMatrix() and addPNGData() to add layers.

Code:
AlphaComposer.h
AlphaComposer.cpp

Public Methods

createInstance

static AlphaComposer *createInstance(int iW, int iH);
iW

Width of image data.

iH

Height of image data.

Prepares a png data target array.

destructor

~AlphaComposer();

The destructor deletes the png data target array.

addMatrix

uchar **addMatrix(double **ppdData, LookUp *pLU);
ppData

A iW x iH array of doubles. each element is a simple value (no color data).

pLU

A color lookup table

The lookup table translates the elements from ppData to red, green, blue and alpha values,

which are added to the png data target array.

addPNGData

uchar **addPNGData(uchar **ppdData);
ppdData

An array holding the rgba values as uchar. The actual array format is iH x 4*iW, where the 4 rgba uchar values are written one after the other. (aucData[13][4*25]: red value for pixel (13,25), aucData[13][4*25+2]: blue value for pixel (13,25)).

Adds the data from ppData to the png data target array.

addPNGDataPar

uchar **addPNGDataPar(uchar **ppdData);
ppdData

An array holding the rgba values as uchar. The actual array format is iH x 4*iW, where the 4 rgba uchar values are written one after the other. (aucData[13][4*25]: red value for pixel (13,25), aucData[13][4*25+2]: blue value for pixel (13,25)).

Basically, a parallelized version of addPNGData().

clear

void    clear();

Clears the png data target array.

getData

uchar **getData();

Returns the contents of the png data target array.