reactos/rosapps/smartpdf/baseutils/pdiff.cc
Klemens Friedl 435a566751 SmartPDF - lightweight pdf viewer app for rosapps
* sumatrapdf - vendor import
* everything compiles (libjpeg, poppler, fitz, sumatrapdf)
* does NOT link

(remove the comment tags in the parent directory.rbuild file (rosapps dir) to build it)

svn path=/trunk/; revision=29295
2007-09-29 08:39:35 +00:00

387 lines
11 KiB
C++

/*
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
Code from http://pdiff.svn.sourceforge.net
*/
#include "pdiff.h"
#include <math.h>
#include <stdio.h>
#ifndef M_PI
#define M_PI 3.14159265f
#endif
CompareArgs::CompareArgs()
{
ImgA = NULL;
ImgB = NULL;
ImgDiff = NULL;
FieldOfView = 45.0f;
Gamma = 2.2f;
Luminance = 100.0f;
}
CompareArgs::~CompareArgs()
{
if (ImgA) delete ImgA;
if (ImgB) delete ImgB;
if (ImgDiff) delete ImgDiff;
}
#define MAX_PYR_LEVELS 8
class LPyramid
{
public:
LPyramid(float *image, int width, int height);
virtual ~LPyramid();
float Get_Value(int x, int y, int level);
protected:
float *Copy(float *img);
void Convolve(float *a, float *b);
// Succesively blurred versions of the original image
float *Levels[MAX_PYR_LEVELS];
int Width;
int Height;
};
LPyramid::LPyramid(float *image, int width, int height) :
Width(width),
Height(height)
{
// Make the Laplacian pyramid by successively
// copying the earlier levels and blurring them
for (int i=0; i<MAX_PYR_LEVELS; i++) {
if (i == 0) {
Levels[i] = Copy(image);
} else {
Levels[i] = new float[Width * Height];
Convolve(Levels[i], Levels[i - 1]);
}
}
}
LPyramid::~LPyramid()
{
for (int i=0; i<MAX_PYR_LEVELS; i++) {
if (Levels[i]) delete Levels[i];
}
}
float *LPyramid::Copy(float *img)
{
int max = Width * Height;
float *out = new float[max];
for (int i = 0; i < max; i++) out[i] = img[i];
return out;
}
void LPyramid::Convolve(float *a, float *b)
// convolves image b with the filter kernel and stores it in a
{
int y,x,i,j,nx,ny;
const float Kernel[] = {0.05f, 0.25f, 0.4f, 0.25f, 0.05f};
for (y=0; y<Height; y++) {
for (x=0; x<Width; x++) {
int index = y * Width + x;
a[index] = 0.0f;
for (i=-2; i<=2; i++) {
for (j=-2; j<=2; j++) {
nx=x+i;
ny=y+j;
if (nx<0) nx=-nx;
if (ny<0) ny=-ny;
if (nx>=Width) nx=2*(Width-1)-nx;
if (ny>=Height) ny=2*(Height-1)-ny;
a[index] += Kernel[i+2] * Kernel[j+2] * b[ny * Width + nx];
}
}
}
}
}
float LPyramid::Get_Value(int x, int y, int level)
{
int index = x + y * Width;
int l = level;
if (l > MAX_PYR_LEVELS) l = MAX_PYR_LEVELS;
return Levels[level][index];
}
/*
* Given the adaptation luminance, this function returns the
* threshold of visibility in cd per m^2
* TVI means Threshold vs Intensity function
* This version comes from Ward Larson Siggraph 1997
*/
float tvi(float adaptation_luminance)
{
// returns the threshold luminance given the adaptation luminance
// units are candelas per meter squared
float log_a, r, result;
log_a = log10f(adaptation_luminance);
if (log_a < -3.94f) {
r = -2.86f;
} else if (log_a < -1.44f) {
r = powf(0.405f * log_a + 1.6f , 2.18f) - 2.86f;
} else if (log_a < -0.0184f) {
r = log_a - 0.395f;
} else if (log_a < 1.9f) {
r = powf(0.249f * log_a + 0.65f, 2.7f) - 0.72f;
} else {
r = log_a - 1.255f;
}
result = powf(10.0f , r);
return result;
}
// computes the contrast sensitivity function (Barten SPIE 1989)
// given the cycles per degree (cpd) and luminance (lum)
float csf(float cpd, float lum)
{
float a, b, result;
a = 440.0f * powf((1.0f + 0.7f / lum), -0.2f);
b = 0.3f * powf((1.0f + 100.0f / lum), 0.15f);
result = a * cpd * expf(-b * cpd) * sqrtf(1.0f + 0.06f * expf(b * cpd));
return result;
}
/*
* Visual Masking Function
* from Daly 1993
*/
float mask(float contrast)
{
float a, b, result;
a = powf(392.498f * contrast, 0.7f);
b = powf(0.0153f * a, 4.0f);
result = powf(1.0f + b, 0.25f);
return result;
}
// convert Adobe RGB (1998) with reference white D65 to XYZ
void AdobeRGBToXYZ(float r, float g, float b, float &x, float &y, float &z)
{
// matrix is from http://www.brucelindbloom.com/
x = r * 0.576700f + g * 0.185556f + b * 0.188212f;
y = r * 0.297361f + g * 0.627355f + b * 0.0752847f;
z = r * 0.0270328f + g * 0.0706879f + b * 0.991248f;
}
void XYZToLAB(float x, float y, float z, float &L, float &A, float &B)
{
static float xw = -1;
static float yw;
static float zw;
// reference white
if (xw < 0) {
AdobeRGBToXYZ(1, 1, 1, xw, yw, zw);
}
const float epsilon = 216.0f / 24389.0f;
const float kappa = 24389.0f / 27.0f;
float f[3];
float r[3];
r[0] = x / xw;
r[1] = y / yw;
r[2] = z / zw;
for (int i = 0; i < 3; i++) {
if (r[i] > epsilon) {
f[i] = powf(r[i], 1.0f / 3.0f);
} else {
f[i] = (kappa * r[i] + 16.0f) / 116.0f;
}
}
L = 116.0f * f[1] - 16.0f;
A = 500.0f * (f[0] - f[1]);
B = 200.0f * (f[1] - f[2]);
}
unsigned long Yee_Compare(CompareArgs &args)
{
if ((args.ImgA->Get_Width() != args.ImgB->Get_Width()) ||
(args.ImgA->Get_Height() != args.ImgB->Get_Height())) {
return DIFFERENT_SIZES;
}
unsigned int i, dim;
dim = args.ImgA->Get_Width() * args.ImgA->Get_Height();
bool identical = true;
for (i = 0; i < dim; i++) {
if (args.ImgA->Get(i) != args.ImgB->Get(i)) {
identical = false;
break;
}
}
if (identical) {
return IDENTICAL;
}
// assuming colorspaces are in Adobe RGB (1998) convert to XYZ
float *aX = new float[dim];
float *aY = new float[dim];
float *aZ = new float[dim];
float *bX = new float[dim];
float *bY = new float[dim];
float *bZ = new float[dim];
float *aLum = new float[dim];
float *bLum = new float[dim];
float *aA = new float[dim];
float *bA = new float[dim];
float *aB = new float[dim];
float *bB = new float[dim];
unsigned int x, y, w, h;
w = args.ImgA->Get_Width();
h = args.ImgA->Get_Height();
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
float r, g, b, l;
i = x + y * w;
r = powf(args.ImgA->Get_Red(i) / 255.0f, args.Gamma);
g = powf(args.ImgA->Get_Green(i) / 255.0f, args.Gamma);
b = powf(args.ImgA->Get_Blue(i) / 255.0f, args.Gamma);
AdobeRGBToXYZ(r,g,b,aX[i],aY[i],aZ[i]);
XYZToLAB(aX[i], aY[i], aZ[i], l, aA[i], aB[i]);
r = powf(args.ImgB->Get_Red(i) / 255.0f, args.Gamma);
g = powf(args.ImgB->Get_Green(i) / 255.0f, args.Gamma);
b = powf(args.ImgB->Get_Blue(i) / 255.0f, args.Gamma);
AdobeRGBToXYZ(r,g,b,bX[i],bY[i],bZ[i]);
XYZToLAB(bX[i], bY[i], bZ[i], l, bA[i], bB[i]);
aLum[i] = aY[i] * args.Luminance;
bLum[i] = bY[i] * args.Luminance;
}
}
LPyramid *la = new LPyramid(aLum, w, h);
LPyramid *lb = new LPyramid(bLum, w, h);
float num_one_degree_pixels = (float) (2 * tan( args.FieldOfView * 0.5 * M_PI / 180) * 180 / M_PI);
float pixels_per_degree = w / num_one_degree_pixels;
float num_pixels = 1;
unsigned int adaptation_level = 0;
for (i = 0; i < MAX_PYR_LEVELS; i++) {
adaptation_level = i;
if (num_pixels > num_one_degree_pixels) break;
num_pixels *= 2;
}
float cpd[MAX_PYR_LEVELS];
cpd[0] = 0.5f * pixels_per_degree;
for (i = 1; i < MAX_PYR_LEVELS; i++) cpd[i] = 0.5f * cpd[i - 1];
float csf_max = csf(3.248f, 100.0f);
float F_freq[MAX_PYR_LEVELS - 2];
for (i = 0; i < MAX_PYR_LEVELS - 2; i++) F_freq[i] = csf_max / csf( cpd[i], 100.0f);
unsigned int pixels_failed = 0;
for (y = 0; y < h; y++) {
for (x = 0; x < w; x++) {
int index = x + y * w;
float contrast[MAX_PYR_LEVELS - 2];
float sum_contrast = 0;
for (i = 0; i < MAX_PYR_LEVELS - 2; i++) {
float n1 = fabsf(la->Get_Value(x,y,i) - la->Get_Value(x,y,i + 1));
float n2 = fabsf(lb->Get_Value(x,y,i) - lb->Get_Value(x,y,i + 1));
float numerator = (n1 > n2) ? n1 : n2;
float d1 = fabsf(la->Get_Value(x,y,i+2));
float d2 = fabsf(lb->Get_Value(x,y,i+2));
float denominator = (d1 > d2) ? d1 : d2;
if (denominator < 1e-5f) denominator = 1e-5f;
contrast[i] = numerator / denominator;
sum_contrast += contrast[i];
}
if (sum_contrast < 1e-5) sum_contrast = 1e-5f;
float F_mask[MAX_PYR_LEVELS - 2];
float adapt = la->Get_Value(x,y,adaptation_level) + lb->Get_Value(x,y,adaptation_level);
adapt *= 0.5f;
if (adapt < 1e-5) adapt = 1e-5f;
for (i = 0; i < MAX_PYR_LEVELS - 2; i++) {
F_mask[i] = mask(contrast[i] * csf(cpd[i], adapt));
}
float factor = 0;
for (i = 0; i < MAX_PYR_LEVELS - 2; i++) {
factor += contrast[i] * F_freq[i] * F_mask[i] / sum_contrast;
}
if (factor < 1) factor = 1;
if (factor > 10) factor = 10;
float delta = fabsf(la->Get_Value(x,y,0) - lb->Get_Value(x,y,0));
bool pass = true;
// pure luminance test
if (delta > factor * tvi(adapt)) {
pass = false;
} else {
// CIE delta E test with modifications
float color_scale = 1.0f;
// ramp down the color test in scotopic regions
if (adapt < 10.0f) {
color_scale = 1.0f - (10.0f - color_scale) / 10.0f;
color_scale = color_scale * color_scale;
}
float da = aA[index] - bA[index];
float db = aB[index] - bB[index];
da = da * da;
db = db * db;
float delta_e = (da + db) * color_scale;
if (delta_e > factor) {
pass = false;
}
}
if (!pass) {
pixels_failed++;
if (args.ImgDiff) {
args.ImgDiff->Set(255, 0, 0, 255, index);
}
} else {
if (args.ImgDiff) {
args.ImgDiff->Set(0, 0, 0, 255, index);
}
}
}
}
if (aX) delete[] aX;
if (aY) delete[] aY;
if (aZ) delete[] aZ;
if (bX) delete[] bX;
if (bY) delete[] bY;
if (bZ) delete[] bZ;
if (aLum) delete[] aLum;
if (bLum) delete[] bLum;
if (la) delete la;
if (lb) delete lb;
if (aA) delete aA;
if (bA) delete bA;
if (aB) delete aB;
if (bB) delete bB;
return (unsigned long)pixels_failed;
}