diff --git a/lpo-projekt-v2/src/core/histogram.cpp b/lpo-projekt-v2/src/core/histogram.cpp
index 1287666..31fc8ce 100644
--- a/lpo-projekt-v2/src/core/histogram.cpp
+++ b/lpo-projekt-v2/src/core/histogram.cpp
@@ -24,15 +24,63 @@ Histogram::~Histogram()
 
 void Histogram::generate(QImage* image)
 {
-    qDebug() << Q_FUNC_INFO << "Not implemented yet!";
+    qDebug() << Q_FUNC_INFO << "Histogram!";
+    qDebug() << Q_FUNC_INFO << image->height();
+    qDebug() << Q_FUNC_INFO << image->width();
+    for ( int row = 0; row < image->height(); ++row ) {
+        for ( int col = 0; col < image->width(); ++col ) {
+            QColor clrCurrent( image->pixel( row, col ) );
+            if (R->contains(clrCurrent.red())) {
+                R->insert(clrCurrent.red(), R->value(clrCurrent.red()) + 1);
+            } else {
+                R->insert(clrCurrent.red(), 1);
+            }
+            if (G->contains(clrCurrent.green())) {
+                G->insert(clrCurrent.green(), G->value(clrCurrent.green()) + 1);
+            } else {
+                G->insert(clrCurrent.green(), 1);
+            }
+            if (B->contains(clrCurrent.blue())) {
+                B->insert(clrCurrent.blue(), B->value(clrCurrent.blue()) + 1);
+            } else {
+                B->insert(clrCurrent.blue(), 1);
+            }
+            if (L->contains(clrCurrent.alpha())) {
+                L->insert(clrCurrent.alpha(), L->value(clrCurrent.alpha()) + 1);
+            } else {
+                L->insert(clrCurrent.alpha(), 1);
+            }
+        }
+    }
 }
 
 /** Returns the maximal value of the histogram in the given channel */
 int Histogram::maximumValue(Channel selectedChannel = RGB)
 {
-    qDebug() << Q_FUNC_INFO << "Not implemented yet!";
+    qDebug() << Q_FUNC_INFO << "Max value!";
+    qDebug() << Q_FUNC_INFO << selectedChannel;
+    int max = 1;
 
-    return 0;
+    if (selectedChannel == RGB) {
+        qDebug() << Q_FUNC_INFO <<  "RGB";
+        max = maximumValue(RChannel);
+        int maxG = maximumValue(GChannel);
+        if (maxG > max) {
+            max = maxG;
+        }
+        int maxB = maximumValue(BChannel);
+        if (maxB > max) {
+            max = maxB;
+        }
+    } else {
+        qDebug() << Q_FUNC_INFO <<  "selectedChannel";
+        foreach(int value, get(selectedChannel)->values()) {
+            if (value > max) {
+                max = value;
+            }
+        }
+    }
+    return max;
 }
 
 
diff --git a/lpo-projekt-v2/src/core/transformations/histogram_equalization.cpp b/lpo-projekt-v2/src/core/transformations/histogram_equalization.cpp
index ab76cd3..1dc604d 100644
--- a/lpo-projekt-v2/src/core/transformations/histogram_equalization.cpp
+++ b/lpo-projekt-v2/src/core/transformations/histogram_equalization.cpp
@@ -19,7 +19,91 @@ PNM* HistogramEqualization::transform()
 
     PNM* newImage = new PNM(width, height, image->format());
 
-    qDebug() << Q_FUNC_INFO << "Not implemented yet!";
+    if (image->format() == QImage::Format_Indexed8) {
+        double prob[256] = { 0.0 };
+
+        Histogram::Channel channelL = Histogram::Channel::LChannel;
+        QHash<int, int>* histL = image->getHistogram()->get(channelL);
+
+        QHash<int, int>::const_iterator i = histL->constBegin();
+        while (i != histL->constEnd()) {
+            prob[i.key()] = (double)i.value() / (double)(width * height);
+            ++i;
+        }
+
+        double distr[256] = { prob[0] };
+
+        for (int i = 1; i < 256; i++) {
+            distr[i] = distr[i - 1] + prob[i];
+        }
+
+        for (int i = 0; i < 256; i++) {
+            distr[i] = distr[i] * 255;
+        }
+
+        for (int x = 0; x < width; x++) {
+            for (int y = 0; y < height; y++) {
+                newImage->setPixel(x, y, (int)distr[qGray(image->pixel(x, y))]);
+            }
+        }
+
+        return newImage;
+    }
+
+    double probR[256] = { 0.0 };
+    double probG[256] = { 0.0 };
+    double probB[256] = { 0.0 };
+
+    Histogram::Channel channelR = Histogram::Channel::RChannel;
+    Histogram::Channel channelG = Histogram::Channel::GChannel;
+    Histogram::Channel channelB = Histogram::Channel::BChannel;
+    QHash<int, int>* histR = image->getHistogram()->get(channelR);
+    QHash<int, int>* histG = image->getHistogram()->get(channelG);
+    QHash<int, int>* histB = image->getHistogram()->get(channelB);
+
+    QHash<int, int>::const_iterator iR = histR->constBegin();
+    while (iR != histR->constEnd()) {
+        probR[iR.key()] = (double)iR.value() / (double)(width * height);
+        ++iR;
+    }
+
+    QHash<int, int>::const_iterator iG = histG->constBegin();
+    while (iG != histG->constEnd()) {
+        probG[iG.key()] = (double)iG.value() / (double)(width * height);
+        ++iG;
+    }
+
+    QHash<int, int>::const_iterator iB = histB->constBegin();
+    while (iB != histB->constEnd()) {
+        probB[iB.key()] = (double)iB.value() / (double)(width * height);
+        ++iB;
+    }
+
+    double distrR[256] = { probR[0] };
+    double distrG[256] = { probG[0] };
+    double distrB[256] = { probB[0] };
+
+    for (int i = 1; i < 256; i++) {
+        distrR[i] = distrR[i - 1] + probR[i];
+        distrG[i] = distrG[i - 1] + probG[i];
+        distrB[i] = distrB[i - 1] + probB[i];
+    }
+
+    for (int i = 0; i < 256; i++) {
+        distrR[i] = distrR[i] * 255;
+        distrG[i] = distrG[i] * 255;
+        distrB[i] = distrB[i] * 255;
+    }
+
+    for (int i = 0; i < width; i++) {
+        for (int j = 0; j < height; j++) {
+            int r = (int) distrR[qRed( image->pixel(i,j))];
+            int g = (int) distrG[qGreen(image->pixel(i,j))];
+            int b = (int) distrB[qBlue(image->pixel(i,j))];
+
+            newImage->setPixel(i, j, QColor(r,g,b).rgb());
+        }
+    }
 
     return newImage;
 }
diff --git a/lpo-projekt-v2/src/core/transformations/histogram_stretching.cpp b/lpo-projekt-v2/src/core/transformations/histogram_stretching.cpp
index 25440de..726ec20 100644
--- a/lpo-projekt-v2/src/core/transformations/histogram_stretching.cpp
+++ b/lpo-projekt-v2/src/core/transformations/histogram_stretching.cpp
@@ -17,9 +17,100 @@ PNM* HistogramStretching::transform()
     int width  = image->width();
     int height = image->height();
 
+    int minR = INT_MAX;
+    int maxR = INT_MIN;
+    int minG = INT_MAX;
+    int maxG = INT_MIN;
+    int minB = INT_MAX;
+    int maxB = INT_MIN;
+
     PNM* newImage = new PNM(width, height, image->format());
 
-    qDebug() << Q_FUNC_INFO << "Not implemented yet!";
+    if (image->format() == QImage::Format_Indexed8) {
+        Histogram::Channel channelL = Histogram::Channel::LChannel;
+        QHash<int, int>* histL = image->getHistogram()->get(channelL);
+        int minL = INT_MAX;
+        int maxL = INT_MIN;
+
+        QHash<int, int>::const_iterator i = histL->constBegin();
+        while (i != histL->constEnd()) {
+            if (i.key() < minL && i.value() > 0) {
+                minL = i.key();
+            }
+            if (i.key() > maxL && i.value() > 0) {
+                maxL = i.key();
+            }
+            ++i;
+        }
+
+        for (int i = 0; i < width; i++) {
+            for (int j = 0; j < height; j++) {
+                int l = (255 * (qGray(image->pixel(i,j)) - minL)) /(maxL - minL);
+                newImage->setPixel(i,j,l);
+            }
+        }
+
+        return newImage;
+    }
+
+    Histogram::Channel channelR = Histogram::Channel::RChannel;
+    Histogram::Channel channelG = Histogram::Channel::GChannel;
+    Histogram::Channel channelB = Histogram::Channel::BChannel;
+    QHash<int, int>* histR = image->getHistogram()->get(channelR);
+    QHash<int, int>* histG = image->getHistogram()->get(channelG);
+    QHash<int, int>* histB = image->getHistogram()->get(channelB);
+
+    foreach(int i, histR->keys()) {
+            if (i < minR && histR->value(i) > 0) {
+                minR = i;
+            }
+            if (i > maxR && histR->value(i) > 0) {
+                maxR = i;
+            }
+        }
+
+    QHash<int, int>::const_iterator iR = histR->constBegin();
+    while (iR != histR->constEnd()) {
+        if (iR.key() < minR && iR.value() > 0) {
+            minR = iR.key();
+        }
+        if (iR.key() > maxR && iR.value() > 0) {
+            maxR = iR.key();
+        }
+        ++iR;
+    }
+
+    QHash<int, int>::const_iterator iG = histG->constBegin();
+    while (iG != histG->constEnd()) {
+        if (iG.key() < minG && iG.value() > 0) {
+            minG = iG.key();
+        }
+        if (iG.key() > maxG && iG.value() > 0) {
+            maxG = iG.key();
+        }
+        ++iG;
+    }
+
+    QHash<int, int>::const_iterator iB = histB->constBegin();
+    while (iB != histB->constEnd()) {
+        if (iB.key() < minB && iB.value() > 0) {
+            minB = iB.key();
+        }
+        if (iB.key() > maxB && iB.value() > 0) {
+            maxB = iB.key();
+        }
+        ++iB;
+    }
+
+    for (int i = 0; i < width; i++) {
+        for (int j = 0; j < height; j++) {
+            int r = (255 * (qRed(image->pixel(i,j)) - minR)) / (maxR - minR);
+            int g = (255 * (qGreen(image->pixel(i,j)) - minG)) / (maxG - minG);
+            int b = (255 * (qBlue(image->pixel(i,j)) - minB)) / (maxB - minB);
+
+            newImage->setPixel(i,j,QColor(r,g,b).rgb());
+        }
+    }
 
     return newImage;
 }