1/*
2    Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies)
3
4    This library is free software; you can redistribute it and/or
5    modify it under the terms of the GNU Library General Public
6    License as published by the Free Software Foundation; either
7    version 2 of the License, or (at your option) any later version.
8
9    This library is distributed in the hope that it will be useful,
10    but WITHOUT ANY WARRANTY; without even the implied warranty of
11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12    Library General Public License for more details.
13
14    You should have received a copy of the GNU Library General Public License
15    along with this library; see the file COPYING.LIB.  If not, write to
16    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17    Boston, MA 02110-1301, USA.
18*/
19
20#include <QtCore/qmath.h>
21
22#include <QApplication>
23#include <QBuffer>
24#include <QByteArray>
25#include <QImage>
26#include <QStringList>
27
28#include <stdio.h>
29
30int main(int argc, char* argv[])
31{
32    QCoreApplication app(argc, argv);
33
34    qreal tolerance = 0;
35
36    QStringList args = app.arguments();
37    for (int i = 0; i < argc; ++i)
38        if (args[i] == "-t" || args[i] == "--tolerance")
39            tolerance = args[i + 1].toDouble();
40
41    char buffer[2048];
42    QImage actualImage;
43    QImage baselineImage;
44
45    while (fgets(buffer, sizeof(buffer), stdin)) {
46        // remove the CR
47        char* newLineCharacter = strchr(buffer, '\n');
48        if (newLineCharacter)
49            *newLineCharacter = '\0';
50
51        if (!strncmp("Content-Length: ", buffer, 16)) {
52            strtok(buffer, " ");
53            int imageSize = strtol(strtok(0, " "), 0, 10);
54
55            if (imageSize <= 0) {
56                fputs("error, image size must be specified.\n", stdout);
57            } else {
58                unsigned char buffer[2048];
59                QBuffer data;
60
61                // Read all the incoming chunks
62                data.open(QBuffer::WriteOnly);
63                while (imageSize > 0) {
64                    size_t bytesToRead = qMin(imageSize, 2048);
65                    size_t bytesRead = fread(buffer, 1, bytesToRead, stdin);
66                    data.write(reinterpret_cast<const char*>(buffer), bytesRead);
67                    imageSize -= static_cast<int>(bytesRead);
68                }
69
70                // Convert into QImage
71                QImage decodedImage;
72                decodedImage.loadFromData(data.data(), "PNG");
73                decodedImage.convertToFormat(QImage::Format_ARGB32);
74
75                // Place it in the right place
76                if (actualImage.isNull())
77                    actualImage = decodedImage;
78                else
79                    baselineImage = decodedImage;
80            }
81        }
82
83        if (!actualImage.isNull() && !baselineImage.isNull()) {
84
85            if (actualImage.size() != baselineImage.size()) {
86                fprintf(stderr, "error, test and reference image have different properties.\n");
87                fflush(stderr);
88            } else {
89
90                int w = actualImage.width();
91                int h = actualImage.height();
92                QImage diffImage(w, h, QImage::Format_ARGB32);
93
94                int count = 0;
95                qreal sum = 0;
96                qreal maxDistance = 0;
97
98                for (int x = 0; x < w; ++x)
99                    for (int y = 0; y < h; ++y) {
100                        QRgb pixel = actualImage.pixel(x, y);
101                        QRgb basePixel = baselineImage.pixel(x, y);
102                        qreal red = (qRed(pixel) - qRed(basePixel)) / static_cast<float>(qMax(255 - qRed(basePixel), qRed(basePixel)));
103                        qreal green = (qGreen(pixel) - qGreen(basePixel)) / static_cast<float>(qMax(255 - qGreen(basePixel), qGreen(basePixel)));
104                        qreal blue = (qBlue(pixel) - qBlue(basePixel)) / static_cast<float>(qMax(255 - qBlue(basePixel), qBlue(basePixel)));
105                        qreal alpha = (qAlpha(pixel) - qAlpha(basePixel)) / static_cast<float>(qMax(255 - qAlpha(basePixel), qAlpha(basePixel)));
106                        qreal distance = qSqrt(red * red + green * green + blue * blue + alpha * alpha) / 2.0f;
107                        int gray = distance * qreal(255);
108                        diffImage.setPixel(x, y, qRgb(gray, gray, gray));
109                        if (distance >= 1 / qreal(255)) {
110                            count++;
111                            sum += distance;
112                            maxDistance = qMax(maxDistance, distance);
113                        }
114                }
115
116                qreal difference = 0;
117                if (count)
118                    difference = 100 * sum / static_cast<qreal>(w * h);
119                if (difference <= tolerance) {
120                    difference = 0;
121                } else {
122                    difference = qRound(difference * 100) / 100;
123                    difference = qMax(difference, qreal(0.01));
124                }
125
126                if (!count) {
127                    fprintf(stdout, "diff: %01.2f%% passed\n", difference);
128                } else {
129                    QBuffer buffer;
130                    buffer.open(QBuffer::WriteOnly);
131                    diffImage.save(&buffer, "PNG");
132                    buffer.close();
133                    const QByteArray &data = buffer.data();
134                    printf("Content-Length: %lu\n", static_cast<unsigned long>(data.length()));
135
136                    // We have to use the return value of fwrite to avoid "ignoring return value" gcc warning
137                    // See https://bugs.webkit.org/show_bug.cgi?id=45384 for details.
138                    if (fwrite(data.constData(), 1, data.length(), stdout)) {}
139
140                    fprintf(stdout, "diff: %01.2f%% failed\n", difference);
141                }
142
143                fflush(stdout);
144            }
145            actualImage = QImage();
146            baselineImage = QImage();
147        }
148    }
149
150    return 0;
151}
152