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Add perceptualdiff program totest/pdiff.

Browse source 
The perceptualdiff program was written by Hector Yee with contributions
from Scott Corley and Mick Weiss. It is hosted at http://pdiff.sourceforge.net
The source code added here was obtained by:

	svn co https://svn.sourceforge.net/svnroot/pdiff/trunk pdiff

which gave revision 22 of the source code.

The perceptualdiff program is available under the terms of the GNU GPL,
so I've added a note to COPYING about this program, (and the fact that
it is auxiliary only, and does not affect the license of the implementation
of cairo itself).
This commit is contained in:
Carl Worth 2006-11-21 12:15:16 -08:00
parent d9fd942e47
commit 812fd53499
13 changed files with 1341 additions and 3 deletions
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21
COPYING
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@ -1,6 +1,6 @@
Cairo is free software.
Every source file in the implementation of cairo is available to be
Every source file in the implementation[*] of cairo is available to be
redistributed and/or modified under the terms of either the GNU Lesser
General Public License (LGPL) version 2.1 or the Mozilla Public
License (MPL) version 1.1. Some files are available under more
@ -13,5 +13,20 @@ conditions of either license:
COPYING-LGPL-2.1
COPYING-MPL-1.1
Please see each file in the implementation for Copyright and licensing
information.
Please see each file in the implementation for copyright and licensing
information, (in the opening comment of each file).
[*] The implementation of cairo is contained entirely within the "src"
and "pixman" directories of the cairo source distribution. There are
other components of the cairo source distribution (such as the "test"
and "perf") that are auxiliary to the library itself. None of the
source code in these directories contributes to a build of the cairo
library itself, (libcairo.so or cairo.dll or similar).
These auxilary components are also free software, but may be under
different license terms than cairo itself. For example, most of the
test cases in the perf and test directories are made available under
an MIT license to simplify any use of this code for reference purposes
in using cairo itself. Other files might be available under the GNU
General Public License (GPL), for example. Again, please see the
opening comment of each file for copyright and licensing information.

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test/pdiff/CMakeLists.txt Normal file
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PROJECT (PerceptualDiff)
SET(DIFF_SRC PerceptualDiff.cpp LPyramid.cpp RGBAImage.cpp
CompareArgs.cpp Metric.cpp)
ADD_EXECUTABLE (perceptualdiff ${DIFF_SRC})
# look for libtiff
FIND_PATH(TIFF_INCLUDE_DIR tiff.h
/usr/local/include
/usr/include
/opt/local/include
)
FIND_LIBRARY(TIFF_LIBRARY tiff
/usr/lib
/usr/local/lib
/opt/local/lib
)
IF(TIFF_INCLUDE_DIR)
IF(TIFF_LIBRARY)
SET( TIFF_FOUND "YES" )
SET( TIFF_LIBRARIES ${TIFF_LIBRARY} )
ENDIF(TIFF_LIBRARY)
ENDIF(TIFF_INCLUDE_DIR)
IF(TIFF_FOUND)
INCLUDE_DIRECTORIES(${TIFF_INCLUDE_DIR})
TARGET_LINK_LIBRARIES(perceptualdiff ${TIFF_LIBRARY})
ENDIF(TIFF_FOUND)
# look for libpng
FIND_PATH(PNG_INCLUDE_DIR png.h
/usr/local/include
/usr/include
/opt/local/include
)
FIND_LIBRARY(PNG_LIBRARY png
/usr/lib
/usr/local/lib
/opt/local/lib
)
IF(PNG_INCLUDE_DIR)
IF(PNG_LIBRARY)
SET( PNG_FOUND "YES" )
SET( PNG_LIBRARIES ${PNG_LIBRARY} )
ENDIF(PNG_LIBRARY)
ENDIF(PNG_INCLUDE_DIR)
IF(PNG_FOUND)
INCLUDE_DIRECTORIES(${PNG_INCLUDE_DIR})
TARGET_LINK_LIBRARIES(perceptualdiff ${PNG_LIBRARY})
ENDIF(PNG_FOUND)

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test/pdiff/CompareArgs.cpp Normal file
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/*
Comapre Args
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
*/
#include "CompareArgs.h"
#include "RGBAImage.h"
#include <stdio.h>
static const char* copyright =
"PerceptualDiff version 1.0, Copyright (C) 2006 Yangli Hector Yee\n\
PerceptualDiff comes with ABSOLUTELY NO WARRANTY;\n\
This is free software, and you are welcome\n\
to redistribute it under certain conditions;\n\
See the GPL page for details: http://www.gnu.org/copyleft/gpl.html\n\n";
static const char *usage =
"PeceptualDiff image1.tif image2.tif\n\n\
Compares image1.tif and image2.tif using a perceptually based image metric\n\
Options:\n\
\t-verbose : Turns on verbose mode\n\
\t-fov deg : Field of view in degrees (0.1 to 89.9)\n\
\t-threshold p : #pixels p below which differences are ignored\n\
\t-gamma g : Value to convert rgb into linear space (default 2.2)\n\
\t-luminance l : White luminance (default 100.0 cdm^-2)\n\
\t-output o.ppm : Write difference to the file o.ppm\n\
\n\
\n Note: Input files can also be in the PNG format\
\n";
CompareArgs::CompareArgs()
{
ImgA = NULL;
ImgB = NULL;
ImgDiff = NULL;
Verbose = false;
FieldOfView = 45.0f;
Gamma = 2.2f;
ThresholdPixels = 100;
Luminance = 100.0f;
}
CompareArgs::~CompareArgs()
{
if (ImgA) delete ImgA;
if (ImgB) delete ImgB;
if (ImgDiff) delete ImgDiff;
}
bool CompareArgs::Parse_Args(int argc, char **argv)
{
if (argc < 3) {
ErrorStr = copyright;
ErrorStr += usage;
return false;
}
for (int i = 0; i < argc; i++) {
if (i == 1) {
ImgA = RGBAImage::ReadTiff(argv[1]);
if (!ImgA) {
ImgA = RGBAImage::ReadPNG(argv[1]);
if (!ImgA)
{
ErrorStr = "FAIL: Cannot open ";
ErrorStr += argv[1];
ErrorStr += "\n";
return false;
}
}
} else if (i == 2) {
ImgB = RGBAImage::ReadTiff(argv[2]);
if (!ImgB) {
ImgB = RGBAImage::ReadPNG(argv[2]);
if (!ImgB)
{
ErrorStr = "FAIL: Cannot open ";
ErrorStr += argv[2];
ErrorStr += "\n";
return false;
}
}
} else {
if (strstr(argv[i], "-fov")) {
if (i + 1 < argc) {
FieldOfView = (float) atof(argv[i + 1]);
}
} else if (strstr(argv[i], "-verbose")) {
Verbose = true;
} else if (strstr(argv[i], "-threshold")) {
if (i + 1 < argc) {
ThresholdPixels = atoi(argv[i + 1]);
}
} else if (strstr(argv[i], "-gamma")) {
if (i + 1 < argc) {
Gamma = (float) atof(argv[i + 1]);
}
}else if (strstr(argv[i], "-luminance")) {
if (i + 1 < argc) {
Luminance = (float) atof(argv[i + 1]);
}
}else if (strstr(argv[i], "-output")) {
if (i + 1 < argc) {
ImgDiff = new RGBAImage(ImgA->Get_Width(), ImgA->Get_Height(), argv[i+1]);
}
}
}
} // i
return true;
}
void CompareArgs::Print_Args()
{
printf("Field of view is %f degrees\n", FieldOfView);
printf("Threshold pixels is %d pixels\n", ThresholdPixels);
printf("The Gamma is %f\n", Gamma);
printf("The Display's luminance is %f candela per meter squared\n", Luminance);
}

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/*
Comapre Args
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 _COMPAREARGS_H
#define _COMPAREARGS_H
#include <string>
class RGBAImage;
// Args to pass into the comparison function
class CompareArgs
{
public:
CompareArgs();
~CompareArgs();
bool Parse_Args(int argc, char **argv);
void Print_Args();
RGBAImage *ImgA; // Image A
RGBAImage *ImgB; // Image B
RGBAImage *ImgDiff; // Diff image
bool Verbose; // Print lots of text or not
float FieldOfView; // Field of view in degrees
float Gamma; // The gamma to convert to linear color space
float Luminance; // the display's luminance
unsigned int ThresholdPixels; // How many pixels different to ignore
std::string ErrorStr; // Error string
};
#endif

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test/pdiff/LPyramid.cpp Normal file
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/*
Laplacian Pyramid
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
*/
#include "LPyramid.h"
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
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];
}

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test/pdiff/LPyramid.h Normal file
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/*
Laplacian Pyramid
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 _LPYRAMID_H
#define _LPYRAMID_H
#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;
};
#endif // _LPYRAMID_H

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test/pdiff/Metric.cpp Normal file
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/*
Metric
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
*/
#include "Metric.h"
#include "CompareArgs.h"
#include "RGBAImage.h"
#include "LPyramid.h"
#include <math.h>
#ifndef M_PI
#define M_PI 3.14159265f
#endif
/*
* 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]);
}
bool Yee_Compare(CompareArgs &args)
{
if ((args.ImgA->Get_Width() != args.ImgB->Get_Width()) ||
(args.ImgA->Get_Height() != args.ImgB->Get_Height())) {
args.ErrorStr = "Image dimensions do not match\n";
return false;
}
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) {
args.ErrorStr = "Images are binary identical\n";
return true;
}
// 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];
if (args.Verbose) printf("Converting RGB to XYZ\n");
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;
}
}
if (args.Verbose) printf("Constructing Laplacian Pyramids\n");
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;
if (args.Verbose) printf("Performing test\n");
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;
if (pixels_failed < args.ThresholdPixels) {
args.ErrorStr = "Images are perceptually indistinguishable\n";
return true;
}
char different[100];
sprintf(different, "%d pixels are different\n", pixels_failed);
args.ErrorStr = "Images are visibly different\n";
args.ErrorStr += different;
if (args.ImgDiff) {
if (args.ImgDiff->WritePPM()) {
args.ErrorStr += "Wrote difference image to ";
args.ErrorStr+= args.ImgDiff->Get_Name();
args.ErrorStr += "\n";
} else {
args.ErrorStr += "Could not write difference image to ";
args.ErrorStr+= args.ImgDiff->Get_Name();
args.ErrorStr += "\n";
}
}
return false;
}

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/*
Metric
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 _METRIC_H
#define _METRIC_H
class CompareArgs;
// Image comparison metric using Yee's method
// References: A Perceptual Metric for Production Testing, Hector Yee, Journal of Graphics Tools 2004
bool Yee_Compare(CompareArgs &args);
#endif

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/*
PerceptualDiff - a program that compares two images using a perceptual metric
based on the paper :
A perceptual metric for production testing. Journal of graphics tools, 9(4):33-40, 2004, Hector Yee
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
*/
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <string>
#include "LPyramid.h"
#include "RGBAImage.h"
#include "CompareArgs.h"
#include "Metric.h"
int main(int argc, char **argv)
{
CompareArgs args;
if (!args.Parse_Args(argc, argv)) {
printf("%s", args.ErrorStr.c_str());
return -1;
} else {
if (args.Verbose) args.Print_Args();
}
int result = Yee_Compare(args) == true;
if (result) {
printf("PASS: %s\n", args.ErrorStr.c_str());
} else {
printf("FAIL: %s\n", args.ErrorStr.c_str());
}
return result;
}

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pdiff - a program that compares two images using
a perceptually based image metric.
Copyright (C) 2006 Yangli Hector Yee
yeehector@users.sourceforge.net
http://pdiff.sourceforge.net/
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 in the file gpl.txt.
Build Instructions
1. Download cross platform make from http://www.cmake.org
2. Download libtiff from http://www.libtiff.org. Download libpng from http://www.libpng.org
3. Edit CMakeLists.txt to tell it where to find your tiff library
4. Type cmake .
5. Type make . (or on Windows systems cmake makes a Visual Studio
Project file)
6. To specify the install directory, use make install DESTDIR="/home/me/mydist"
Usage
pdiff image1.(tif | png) image2.(tif | png) [options]
-verbose : Turns on verbose mode
-fov deg: field of view, deg, in degrees. Usually between 10.0 to 85.0.
This controls how much of the screen the oberserver is seeing. Front row of
a theatre has a field of view of around 25 degrees. Back row has a field of
view of around 60 degrees.
-threshold p : Sets the number of pixels, p, to reject. For example if p is
100, then the test fails if 100 or more pixels are perceptably different.
-gamma g : The gamma to use to convert to RGB linear space. Default is 2.2
-luminance l: The luminance of the display the observer is seeing. Default
is 100 candela per meter squared
-output foo.ppm : Saves the difference image to foo.ppm
Credits
Hector Yee, project administrator and originator - hectorgon.blogspot.com
Scott Corley, for png file IO code
Mick Weiss, Linux build and release & QA

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/*
RGBAImage.cpp
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
*/
#include "RGBAImage.h"
#include "png.h"
#include "tiff.h"
#include "tiffio.h"
// Reads Tiff Images
RGBAImage* RGBAImage::ReadTiff(char *filename)
{
RGBAImage *fimg = 0;
TIFF* tif = TIFFOpen(filename, "r");
char emsg[1024];
emsg[0] = 0;
if (tif) {
TIFFRGBAImage img;
if (TIFFRGBAImageBegin(&img, tif, 0, emsg)) {
size_t npixels;
uint32* raster;
npixels = img.width * img.height;
raster = (uint32*) _TIFFmalloc(npixels * sizeof (uint32));
if (raster != NULL) {
if (TIFFRGBAImageGet(&img, raster, img.width, img.height)) {
// result is in ABGR
fimg = new RGBAImage(img.width, img.height);
for (int y = img.height - 1; y >= 0; y--) {
for (int x = 0; x < (int) img.width; x++) {
fimg->Set(x,img.height - (y+1), raster[x + y * img.width]);
}
}
}
_TIFFfree(raster);
}
}
TIFFRGBAImageEnd(&img);
}
return fimg;
}
// This portion was written by Scott Corley
RGBAImage* RGBAImage::ReadPNG(char *filename)
{
RGBAImage *fimg = 0;
FILE *fp=fopen(filename, "rb");
if (!fp)
{
return NULL;
}
png_byte header[8];
fread(header, 1, 8, fp);
bool is_png = !png_sig_cmp(header, 0, 8);
if (!is_png)
{
return NULL;
}
png_structp png_ptr = png_create_read_struct
(PNG_LIBPNG_VER_STRING, (png_voidp)NULL,
NULL, NULL);
if (!png_ptr)
return (NULL);
png_infop info_ptr = png_create_info_struct(png_ptr);
if (!info_ptr)
{
png_destroy_read_struct(&png_ptr,
(png_infopp)NULL, (png_infopp)NULL);
return (NULL);
}
png_infop end_info = png_create_info_struct(png_ptr);
if (!end_info)
{
png_destroy_read_struct(&png_ptr, &info_ptr,
(png_infopp)NULL);
return (NULL);
}
png_init_io(png_ptr, fp);
png_set_sig_bytes(png_ptr, 8);
png_read_png(png_ptr, info_ptr, 0, NULL);
png_bytep *row_pointers;
row_pointers = png_get_rows(png_ptr, info_ptr);
fimg = new RGBAImage(png_ptr->width, png_ptr->height);
for (int y = 0; y < (int) png_ptr->height; y++) {
for (int x = 0; x < (int) png_ptr->width; x++) {
uint32 value = 0;
if (png_ptr->color_type == PNG_COLOR_TYPE_RGB_ALPHA)
value = ((uint32)row_pointers[y][x*4]) | (((uint32)row_pointers[y][x*4+1])<<8) | (((uint32)row_pointers[y][x*4+2])<<16) |(((uint32)row_pointers[y][x*4+3])<<24);
else if (png_ptr->color_type == PNG_COLOR_TYPE_RGB)
value = ((uint32)row_pointers[y][x*3] /*B*/) | (((uint32)row_pointers[y][x*3+1] /*G*/)<<8) | (((uint32)row_pointers[y][x*3+2]/*R*/)<<16) | (0xFFUL << 24);
fimg->Set(x,y, value);
}
}
png_read_destroy(png_ptr, info_ptr, end_info);
return fimg;
}
bool RGBAImage::WritePPM()
{
if (Width <= 0) return false;
if (Height <=0 ) return false;
FILE *out = fopen(Name.c_str(), "wb");
if (!out) return false;
fprintf(out, "P6\n%d %d 255\n", Width, Height);
for (int y = 0; y < Height; y++) {
for (int x = 0; x < Width; x++) {
int i = x + y * Width;
unsigned char r = Get_Red(i);
unsigned char g = Get_Green(i);
unsigned char b = Get_Blue(i);
fwrite(&r, 1, 1, out);
fwrite(&g, 1, 1, out);
fwrite(&b, 1, 1, out);
}
}
fclose(out);
return true;
}

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/*
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 _RGAIMAGE_H
#define _RGBAIMAGE_H
#include<string>
// assumes data is in the ABGR format
class RGBAImage
{
public:
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; }
unsigned char Get_Red(unsigned int i) { return (Data[i] & 0xFF); }
unsigned char Get_Green(unsigned int i) { return ((Data[i]>>8) & 0xFF); }
unsigned char Get_Blue(unsigned int i) { return ((Data[i]>>16) & 0xFF); }
unsigned char Get_Alpha(unsigned int i) { return ((Data[i]>>24) & 0xFF); }
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; }
void Set(int x, int y, unsigned int d) { Data[x + y * Width] = d; }
unsigned int Get(int x, int y) const { return Data[x + y * Width]; }
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;
};
#endif

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GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
Preamble
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Foundation's software and to any other program whose authors commit to
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0. This License applies to any program or other work which contains
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Whether that is true depends on what the Program does.
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END OF TERMS AND CONDITIONS
How to Apply These Terms to Your New Programs
If you develop a new program, and you want it to be of the greatest
possible use to the public, the best way to achieve this is to make it
free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest
to attach them to the start of each source file to most effectively
convey the exclusion of warranty; and each file should have at least
the "copyright" line and a pointer to where the full notice is found.
<one line to give the program's name and a brief idea of what it does.>
Copyright (C) <year> <name of author>
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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this
when it starts in an interactive mode:
Gnomovision version 69, Copyright (C) year name of author
Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
This is free software, and you are welcome to redistribute it
under certain conditions; type `show c' for details.
The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License. Of course, the commands you use may
be called something other than `show w' and `show c'; they could even be
mouse-clicks or menu items--whatever suits your program.
You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the program, if
necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the program
`Gnomovision' (which makes passes at compilers) written by James Hacker.
<signature of Ty Coon>, 1 April 1989
Ty Coon, President of Vice
This General Public License does not permit incorporating your program into
proprietary programs. If your program is a subroutine library, you may
consider it more useful to permit linking proprietary applications with the
library. If this is what you want to do, use the GNU Lesser General
Public License instead of this License.