cairo/test/pdiff/RGBAImage.h

105 lines
3.8 KiB
C++

/*
RGBAImage.h
Copyright (C) 2006 Yangli Hector Yee
This program is free software; you can redistribute it and/or modify it under the terms of the
GNU General Public License as published by the Free Software Foundation; either version 2 of the License,
or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program;
if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef _RGBAIMAGE_H
#define _RGBAIMAGE_H
#include<string>
#include<cairo.h>
/* assumes data is in the ABGR format */
class RGBAImage
{
public:
RGBAImage() { Width = 0; Height = 0; Data = 0; }
RGBAImage(int w, int h, const char *name = 0)
{
Width = w;
Height = h;
if (name) Name = name;
Data = new unsigned int[w * h];
};
~RGBAImage() { if (Data) delete[] Data; }
virtual unsigned char Get_Red(unsigned int i) { return (Data[i] & 0xFF); }
virtual unsigned char Get_Green(unsigned int i) { return ((Data[i]>>8) & 0xFF); }
virtual unsigned char Get_Blue(unsigned int i) { return ((Data[i]>>16) & 0xFF); }
virtual unsigned char Get_Alpha(unsigned int i) { return ((Data[i]>>24) & 0xFF); }
virtual void Set(unsigned char r, unsigned char g, unsigned char b, unsigned char a, unsigned int i)
{ Data[i] = r | (g << 8) | (b << 16) | (a << 24); }
int Get_Width(void) const { return Width; }
int Get_Height(void) const { return Height; }
virtual void Set(int x, int y, unsigned int d) { Data[x + y * Width] = d; }
virtual unsigned int Get(int x, int y) const { return Data[x + y * Width]; }
virtual unsigned int Get(int i) const { return Data[i]; }
const std::string &Get_Name(void) const { return Name; }
bool WritePPM();
static RGBAImage* ReadTiff(char *filename);
static RGBAImage* ReadPNG(char *filename);
protected:
int Width;
int Height;
std::string Name;
unsigned int *Data;
};
class RGBACairoImage : public RGBAImage
{
public:
RGBACairoImage (cairo_surface_t *surface)
{
Width = cairo_image_surface_get_width (surface);
Height = cairo_image_surface_get_height (surface);
Data = (unsigned int *) cairo_image_surface_get_data (surface);
if (cairo_image_surface_get_stride (surface) != 4 * Width) {
fprintf (stderr, "Error: Currently only support images where stride == 4 * width\n");
exit (1);
}
}
~RGBACairoImage() { }
unsigned int ARGB_to_ABGR(unsigned int pixel) const {
unsigned int new_pixel;
new_pixel = pixel & 0xff00ff00;
new_pixel |= (pixel & 0x00ff0000) >> 16;
new_pixel |= (pixel & 0x000000ff) << 16;
return new_pixel;
}
unsigned int Get_Unpremultiply(unsigned int i) const {
uint32_t pixel;
uint8_t alpha;
pixel = Data[i];
alpha = (pixel & 0xff000000) >> 24;
if (alpha == 0)
return 0;
return (alpha << 24) |
((((pixel & 0xff0000) >> 16) * 255 + alpha / 2) / alpha) << 16 |
((((pixel & 0x00ff00) >> 8) * 255 + alpha / 2) / alpha) << 8 |
((((pixel & 0x0000ff) >> 0) * 255 + alpha / 2) / alpha) << 0;
}
unsigned char Get_Alpha(unsigned int i) { return (Get_Unpremultiply(i) & 0xff000000) >> 24;}
unsigned char Get_Red(unsigned int i) { return (Get_Unpremultiply(i) & 0x00ff0000) >> 16;}
unsigned char Get_Green(unsigned int i) { return (Get_Unpremultiply(i) & 0x0000ff00) >> 8;}
unsigned char Get_Blue(unsigned int i) { return (Get_Unpremultiply(i) & 0x000000ff) >> 0;}
unsigned int Get(int x, int y) const { return Get(Width * y + x); }
unsigned int Get(int i) const { return ARGB_to_ABGR(Get_Unpremultiply(i)); }
};
#endif