// Copyright (C) 2007 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#ifndef DLIB_DNG_SHAREd_
#define DLIB_DNG_SHAREd_
#include "../pixel.h"
#include <cmath>
#include "../uintn.h"
namespace dlib
{
namespace dng_helpers_namespace
{
enum
{
grayscale = 1,
rgb,
hsi,
rgb_paeth,
rgb_alpha,
rgb_alpha_paeth,
grayscale_16bit,
grayscale_float
};
const unsigned long dng_magic_byte = 100;
template <typename T>
rgb_pixel predictor_rgb_paeth (const T& img, long row, long col)
/*
This is similar to the Paeth filter from the PNG image format.
*/
{
// a = left, b = above, c = upper left
rgb_pixel a(0,0,0), b(0,0,0), c(0,0,0);
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
else
assign_pixel(a,(unsigned char)0);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
else
assign_pixel(c,(unsigned char)0);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
else
assign_pixel(b,(unsigned char)0);
rgb_pixel p;
p.red = a.red + b.red - c.red;
p.green = a.green + b.green - c.green;
p.blue = a.blue + b.blue - c.blue;
short pa = std::abs((short)p.red - (short)a.red) +
std::abs((short)p.green - (short)a.green) +
std::abs((short)p.blue - (short)a.blue);
short pb = std::abs((short)p.red - (short)b.red) +
std::abs((short)p.green - (short)b.green) +
std::abs((short)p.blue - (short)b.blue);
short pc = std::abs((short)p.red - (short)c.red) +
std::abs((short)p.green - (short)c.green) +
std::abs((short)p.blue - (short)c.blue);
if (pa <= pb && pa <= pc)
return a;
else if (pb <= pc)
return b;
else
return c;
}
template <typename T>
rgb_pixel predictor_rgb (const T& img, long row, long col)
{
// a = left, b = above, c = upper left
rgb_pixel a(0,0,0), b(0,0,0), c(0,0,0);
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
else
assign_pixel(a,(unsigned char)0);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
else
assign_pixel(c,(unsigned char)0);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
else
assign_pixel(b,(unsigned char)0);
rgb_pixel p;
p.red = a.red + b.red - c.red;
p.green = a.green + b.green - c.green;
p.blue = a.blue + b.blue - c.blue;
return p;
}
template <typename T>
rgb_alpha_pixel predictor_rgb_alpha_paeth (const T& img, long row, long col)
/*
This is similar to the Paeth filter from the PNG image format.
*/
{
// a = left, b = above, c = upper left
rgb_alpha_pixel a, b, c;
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
else
assign_pixel(a,(unsigned char)0);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
else
assign_pixel(c,(unsigned char)0);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
else
assign_pixel(b,(unsigned char)0);
rgb_alpha_pixel p;
p.red = a.red + b.red - c.red;
p.green = a.green + b.green - c.green;
p.blue = a.blue + b.blue - c.blue;
short pa = std::abs((short)p.red - (short)a.red) +
std::abs((short)p.green - (short)a.green) +
std::abs((short)p.blue - (short)a.blue);
short pb = std::abs((short)p.red - (short)b.red) +
std::abs((short)p.green - (short)b.green) +
std::abs((short)p.blue - (short)b.blue);
short pc = std::abs((short)p.red - (short)c.red) +
std::abs((short)p.green - (short)c.green) +
std::abs((short)p.blue - (short)c.blue);
if (pa <= pb && pa <= pc)
return a;
else if (pb <= pc)
return b;
else
return c;
}
template <typename T>
rgb_alpha_pixel predictor_rgb_alpha (const T& img, long row, long col)
{
// a = left, b = above, c = upper left
rgb_alpha_pixel a, b, c;
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
else
assign_pixel(a,(unsigned char)0);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
else
assign_pixel(c,(unsigned char)0);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
else
assign_pixel(b,(unsigned char)0);
rgb_alpha_pixel p;
p.red = a.red + b.red - c.red;
p.green = a.green + b.green - c.green;
p.blue = a.blue + b.blue - c.blue;
p.alpha = a.alpha + b.alpha - c.alpha;
return p;
}
template <typename T>
hsi_pixel predictor_hsi (const T& img, long row, long col)
{
// a = left, b = above, c = upper left
hsi_pixel a(0,0,0), b(0,0,0), c(0,0,0);
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
else
assign_pixel(a,(unsigned char)0);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
else
assign_pixel(c,(unsigned char)0);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
else
assign_pixel(b,(unsigned char)0);
hsi_pixel p;
p.h = a.h + b.h - c.h;
p.s = a.s + b.s - c.s;
p.i = a.i + b.i - c.i;
return p;
}
template <typename T>
unsigned char predictor_grayscale (const T& img, long row, long col)
{
// a = left, b = above, c = upper left
unsigned char a = 0, b = 0, c = 0;
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
unsigned char p = a + b - c;
return p;
}
template <typename T>
uint16 predictor_grayscale_16 (const T& img, long row, long col)
{
// a = left, b = above, c = upper left
uint16 a = 0, b = 0, c = 0;
const long c1 = col-1;
const long r1 = row-1;
if (c1 >= 0)
assign_pixel(a, img[row][c1]);
if (c1 >= 0 && r1 >= 0)
assign_pixel(c, img[r1][c1]);
if (r1 >= 0)
assign_pixel(b, img[r1][col]);
uint16 p = a + b - c;
return p;
}
}
}
#endif // DLIB_DNG_SHAREd_