Add histogram

CMakeLists.txt

@@ -33,6 +33,7 @@ set(TENMON_SRC
     databaseview.cpp databaseview.h
     delete.cpp
     filesystemwidget.cpp filesystemwidget.h
+    histogram.cpp histogram.h
     imageinfo.cpp imageinfo.h
     imageringlist.cpp imageringlist.h
     imagescrollarea.cpp

histogram.cpp

@@ -0,0 +1,84 @@
+#include "histogram.h"
+#include <cmath>
+#include <algorithm>
+#include <QPainter>
+#include <QDebug>
+
+Histogram::Histogram(QWidget *parent) : QWidget(parent)
+{
+    setStyleSheet("QWidget { background: white; color: black; } ");
+}
+
+void Histogram::imageLoaded(Image *img)
+{
+    if(img && img->rawImage())
+    {
+        m_histogram = img->rawImage()->imageStats().m_histogram[0];
+        m_points.clear();
+        update();
+    }
+}
+
+void Histogram::paintEvent(QPaintEvent *)
+{
+    QPainter painter(this);
+    painter.fillRect(rect(), Qt::black);
+
+    uint h = height();
+    uint w = width();
+
+    if(m_histogram.size())
+    {
+
+        if(m_points.size() != w)
+        {
+            m_points.clear();
+            for(uint64_t i = 0; i < w; i++)
+            {
+                uint32_t sum = 0;
+                uint64_t start = i * m_histogram.size() / w;
+                uint64_t end =(i+1) * m_histogram.size() / w;
+                for(uint64_t o = start; o < end; o++)
+                    sum += m_histogram[o];
+                m_points.push_back(sum);
+            }
+            float scale = *std::max_element(m_points.begin(), m_points.end());
+            if(m_log)
+            {
+                scale = std::log(scale);
+                std::for_each(m_points.begin(), m_points.end(), [scale](float &x){ x = (x > 0 ? std::log(x) : 0.0f) / scale; });
+            }
+            else
+            {
+                std::for_each(m_points.begin(), m_points.end(), [scale](float &x){ x /= scale; });
+            }
+        }
+        std::vector<QPointF> points;
+        points.push_back(QPointF(0, h));
+        for(size_t i = 0; i < m_points.size(); i++)
+        {
+            points.push_back(QPointF(i, h - m_points[i] * h));
+        }
+        points.push_back(QPoint(w, h));
+        painter.setBrush(Qt::gray);
+        painter.setPen(Qt::white);
+
+        painter.drawPolygon(&points[0], points.size());
+    }
+
+    QStyleOptionButton button;
+    button.initFrom(this);
+    button.state = m_log ? QStyle::State_On : QStyle::State_Off;
+    button.text = tr("Logarithmic scale");
+    button.rect = style()->subElementRect(QStyle::SE_CheckBoxClickRect, &button, this);
+    button.rect.moveTop(0);
+    button.rect.moveRight(w);
+    style()->drawControl(QStyle::CE_CheckBox, &button, &painter, this);
+}
+
+void Histogram::mouseReleaseEvent(QMouseEvent *)
+{
+    m_log = !m_log;
+    m_points.clear();
+    update();
+}

histogram.h

@@ -0,0 +1,22 @@
+#ifndef HISTOGRAM_H
+#define HISTOGRAM_H
+
+#include <QWidget>
+#include "imageringlist.h"
+
+class Histogram : public QWidget
+{
+    Q_OBJECT
+    std::vector<uint32_t> m_histogram;
+    std::vector<float> m_points;
+    bool m_log = false;
+public:
+    explicit Histogram(QWidget *parent = nullptr);
+public slots:
+    void imageLoaded(Image *img);
+protected:
+    void paintEvent(QPaintEvent *) override;
+    void mouseReleaseEvent(QMouseEvent *) override;
+};
+
+#endif // HISTOGRAM_H

mainwindow.cpp

@@ -23,6 +23,7 @@
 #include "about.h"
 #include "statusbar.h"
 #include "settingsdialog.h"
+#include "histogram.h"
 
 #ifdef __linux__
 #include <sys/ioctl.h>
@@ -120,6 +121,13 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     databaseViewDock->hide();
     addDockWidget(Qt::LeftDockWidgetArea, filetreeDock);
 
+    Histogram *histogram = new Histogram(this);
+    QDockWidget *histogramDock = new QDockWidget(tr("Histogram"), this);
+    histogramDock->setWidget(histogram);
+    histogramDock->setObjectName("histogramDock");
+    histogramDock->show();
+    addDockWidget(Qt::LeftDockWidgetArea, histogramDock);
+
     setWindowTitle(tr("Tenmon"));
 
     connect(m_ringList, SIGNAL(pixmapLoaded(Image*)), this, SLOT(pixmapLoaded(Image*)));
@@ -128,6 +136,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     connect(m_ringList, SIGNAL(currentImageChanged(int)), m_filesystem, SLOT(selectFile(int)));
     connect(m_ringList, &ImageRingList::thumbnailLoaded, m_imageGL->imageWidget(), &ImageWidget::thumbnailLoaded);
     connect(m_ringList, &ImageRingList::pixmapLoaded, m_stretchPanel, &StretchToolbar::imageLoaded);
+    connect(m_ringList, &ImageRingList::pixmapLoaded, histogram, &Histogram::imageLoaded);
     connect(m_imageGL->imageWidget(), &ImageWidget::fileDropped, this, static_cast<void (MainWindow::*)(const QString &)>(&MainWindow::loadFile));
 
     QMenu *fileMenu = new QMenu(tr("File"), this);
@@ -207,6 +216,7 @@ MainWindow::MainWindow(QWidget *parent) : QMainWindow(parent)
     dockMenu->addAction(filesystemDock->toggleViewAction());
     dockMenu->addAction(databaseViewDock->toggleViewAction());
     dockMenu->addAction(filetreeDock->toggleViewAction());
+    dockMenu->addAction(histogramDock->toggleViewAction());
     menuBar()->addMenu(dockMenu);
 
     QMenu *helpMenu = menuBar()->addMenu(tr("Help"));

rawimage.cpp

@@ -197,6 +197,9 @@ void calcStats(const T *data, size_t n, RawImage::Stats &stats)
             stats.m_mad[i] /= 65535.0;
         }
     }
+
+    for(size_t i = 0; i < ch; i++)
+        stats.m_histogram[i] = std::vector<uint32_t>(histogram[i], histogram[i] + histSize);
 }
 
 void RawImage::calcStats()

rawimage.h

@@ -57,6 +57,7 @@ public:
         double m_max[4] = {0.0};
         double m_mad[4] = {0.0};
         uint32_t m_saturated[4] = {0};
+        std::vector<uint32_t> m_histogram[4];
     };
 protected:
     std::unique_ptr<PixelType[]> m_pixels;