From d4beb46f28e4011fdba48248ae31fb31b1e9e849 Mon Sep 17 00:00:00 2001
From: Manuel Dewald <mdewald@redhat.com>
Date: Thu, 4 Mar 2021 14:40:11 +0100
Subject: [PATCH] Add text overlays

---
 README.md          |  15 ++++-
 src/main.cpp       |  11 +++-
 src/mainwindow.cpp |  28 +++++++++
 src/mainwindow.h   |   6 ++
 src/overlay.cpp    | 144 +++++++++++++++++++++++++++++++++++++++++++++
 src/overlay.h      |  60 +++++++++++++++++++
 src/slide.pro      |   2 +
 7 files changed, 262 insertions(+), 4 deletions(-)
 create mode 100644 src/overlay.cpp
 create mode 100644 src/overlay.h

diff --git a/README.md b/README.md
index cb6d081..af2ea9a 100644
--- a/README.md
+++ b/README.md
@@ -16,7 +16,7 @@ This project is maintained by myself during my spare time. If you like and use i
 ## Usage
 
 ```
-slide [-t rotation_seconds] [-o background_opacity(0..255)] [-b blur_radius] -p image_folder -r
+slide [-t rotation_seconds] [-o background_opacity(0..255)] [-b blur_radius] -p image_folder [-r] [-O overlay_string]
 ```
 
 * `image_folder`: where to search for images (.jpg files)
@@ -26,7 +26,18 @@ slide [-t rotation_seconds] [-o background_opacity(0..255)] [-b blur_radius] -p
 * `rotation_seconds(default=30)`: time until next random image is chosen from the given folder
 * `background_opacity(default=150)`: opacity of the background filling image between 0 (black background) and 255
 * `blur_radius(default=20)`: blur radius of the background filling image
-
+* `-O` is used to create a overlay string.
+  * It defines overlays for all four edges in the order `top-left;top-right;bottom-left;bottom-right`
+  * All edges overlays are separated by `;`
+  * Each edge can either be just a test or contain formatting in the form `margin|fontsize|text`
+  * the text can contain special strings which are replaced during rendering:
+    * `<time>` current time
+    * `<date>` current date
+    * `<datetime>` current time and date
+    * `<filename>` filename of the current image
+    * `<exifdatetime>` time stamp from the EXIF data of the image
+  * Example: `slide -p ./images -O "20|60|Time: <time>;;;Picture taken at <exifdatetime>"`
+      
 ## Dependencies
 
 * libexif
diff --git a/src/main.cpp b/src/main.cpp
index a176639..8943b49 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2,6 +2,7 @@
 #include "imageselector.h"
 #include "imageswitcher.h"
 #include "pathtraverser.h"
+#include "overlay.h"
 #include <QApplication>
 #include <iostream>
 #include <sys/file.h>
@@ -28,7 +29,8 @@ int main(int argc, char *argv[])
   bool recursive = false;
   bool shuffle = false;
   bool sorted = false;
-  while ((opt = getopt(argc, argv, "b:p:t:o:rsS")) != -1) {
+  std::string overlay = "";
+  while ((opt = getopt(argc, argv, "b:p:t:o:O:rsS")) != -1) {
     switch (opt) {
       case 'p':
         path = optarg;
@@ -52,6 +54,9 @@ int main(int argc, char *argv[])
       case 'S':
         sorted = true;
         break;
+      case 'O':
+        overlay = optarg;
+        break;
       default: /* '?' */
         usage(argv[0]);
         return 1;
@@ -88,7 +93,9 @@ int main(int argc, char *argv[])
   {
     selector = std::unique_ptr<ImageSelector>(new RandomImageSelector(pathTraverser));
   }
-
+  std::cout << "Overlay input: " << overlay << std::endl;
+  Overlay o(overlay);
+  w.setOverlay(&o);
   w.show();
 
   ImageSwitcher switcher(w, rotationSeconds * 1000, selector);
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 7cf7c45..591b71e 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -1,4 +1,5 @@
 #include "mainwindow.h"
+#include "overlay.h"
 #include "ui_mainwindow.h"
 #include <QLabel>
 #include <QPixmap>
@@ -9,6 +10,7 @@
 #include <iostream>
 #include <QPainter>
 #include <QTimer>
+#include <QRect>
 #include <QGraphicsScene>
 #include <QGraphicsPixmapItem>
 #include <sstream>
@@ -99,6 +101,14 @@ void MainWindow::updateImage()
     QPixmap p( currentImage.c_str() );
     QPixmap rotated = getRotatedPixmap(p);
     QPixmap scaled = getScaledPixmap(rotated);
+    
+    if (overlay != NULL)
+    {
+      drawText(scaled, overlay->getMarginTopLeft(), overlay->getFontsizeTopLeft(), overlay->getRenderedTopLeft(currentImage).c_str(), Qt::AlignTop|Qt::AlignLeft);
+      drawText(scaled, overlay->getMarginTopRight(), overlay->getFontsizeTopRight(), overlay->getRenderedTopRight(currentImage).c_str(), Qt::AlignTop|Qt::AlignRight);
+      drawText(scaled, overlay->getMarginBottomLeft(), overlay->getFontsizeBottomLeft(), overlay->getRenderedBottomLeft(currentImage).c_str(), Qt::AlignBottom|Qt::AlignLeft);
+      drawText(scaled, overlay->getMarginBottomRight(), overlay->getFontsizeBottomRight(), overlay->getRenderedBottomRight(currentImage).c_str(), Qt::AlignBottom|Qt::AlignRight);
+    }
 
     QLabel *label = this->findChild<QLabel*>("image");
     label->setPixmap(scaled);
@@ -112,6 +122,24 @@ void MainWindow::updateImage()
     update();
 }
 
+void MainWindow::drawText(QPixmap& image, int margin, int fontsize, QString text, int alignment) {
+  //std::cout << "text: " << text.toStdString()  << " margin: " << margin << " fontsize: " << fontsize<< std::endl;
+  QPainter pt(&image);
+  pt.setPen(QPen(Qt::white));
+  pt.setFont(QFont("Sans", fontsize, QFont::Bold));
+  QRect marginRect = image.rect().adjusted(
+      margin,
+      margin,
+      margin*-1,
+      margin*-1);
+  pt.drawText(marginRect, alignment, text);
+}
+
+void MainWindow::setOverlay(Overlay* o)
+{
+  overlay = o;
+}
+
 QPixmap MainWindow::getRotatedPixmap(const QPixmap& p)
 {
     QMatrix matrix;
diff --git a/src/mainwindow.h b/src/mainwindow.h
index 636ebb4..6fa9e2b 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -9,6 +9,7 @@ class MainWindow;
 }
 class QLabel;
 class QKeyEvent;
+class Overlay;
 
 class MainWindow : public QMainWindow
 {
@@ -23,6 +24,7 @@ public:
     void setBlurRadius(unsigned int blurRadius);
     void setBackgroundOpacity(unsigned int opacity);
     void warn(std::string text);
+    void setOverlay(Overlay* overlay);
 
 private:
     Ui::MainWindow *ui;
@@ -31,6 +33,10 @@ private:
     unsigned int blurRadius = 20;
     unsigned int backgroundOpacity = 150;
 
+    Overlay* overlay;
+
+    void drawText(QPixmap& image, int margin, int fontsize, QString text, int alignment);
+
     void updateImage();
     int getImageRotation();
 
diff --git a/src/overlay.cpp b/src/overlay.cpp
new file mode 100644
index 0000000..28729ad
--- /dev/null
+++ b/src/overlay.cpp
@@ -0,0 +1,144 @@
+#include "overlay.h"
+#include <QString>
+#include <QDateTime>
+#include <libexif/exif-data.h>
+#include <unistd.h>
+#include <QDate>
+#include <QLocale>
+#include <QTime>
+#include <QStringList>
+#include <QRegExp>
+#include <iostream>
+
+Overlay::Overlay(const std::string overlayInput):
+  overlayInput(overlayInput)
+{
+  parseInput();
+}
+
+Overlay::~Overlay() {}
+
+void Overlay::parseInput() {
+  QString str = QString(overlayInput.c_str());
+  QStringList corners = str.split(QLatin1Char(';'));
+  if (corners.size() > 0) {
+    QStringList components = getOverlayComponents(corners[0]);
+    topLeftTemplate = getTemplate(components);
+    topLeftMargin = getMargin(components);
+    topLeftFontsize = getFontsize(components);
+  }
+  if (corners.size() > 1) {
+    QStringList components = getOverlayComponents(corners[1]);
+    topRightTemplate = getTemplate(components);
+    topRightMargin = getMargin(components);
+    topRightFontsize = getFontsize(components);
+  }
+  if (corners.size() > 2) {
+    QStringList components = getOverlayComponents(corners[2]);
+    bottomLeftTemplate = getTemplate(components);
+    bottomLeftMargin = getMargin(components);
+    bottomLeftFontsize = getFontsize(components);
+  }
+  if (corners.size() > 3) {
+    QStringList components = getOverlayComponents(corners[3]);
+    bottomRightTemplate = getTemplate(components);
+    bottomRightMargin = getMargin(components);
+    bottomRightFontsize = getFontsize(components);
+  }
+}
+
+QString Overlay::getTemplate(QStringList components){
+  if (components.size()>3) {
+    std::cout << "template: " << components[3].toStdString() << std::endl;
+    return components[3];
+  }
+  return "";
+}
+
+int Overlay::getMargin(QStringList components){
+  if (components.size()>1) {
+    std::cout << "margin: " << components[1].toStdString() << std::endl;
+    int num = components[1].toInt();
+    if (num > 0) {
+      return num;
+    }
+  }
+
+  return 20;
+}
+
+int Overlay::getFontsize(QStringList components){
+  if (components.size()>2) {
+    std::cout << "fontsize: " << components[2].toStdString() << std::endl;
+    int num = components[2].toInt();
+    if (num > 0) {
+      return num;
+    }
+  }
+
+  return 12;
+}
+
+
+QStringList Overlay::getOverlayComponents(QString corner) {
+  QRegExp regex("([\\d]*)\\|([\\d]*)\\|(.*)");
+  if (regex.exactMatch(corner)){
+    return regex.capturedTexts();
+  }
+  QStringList malformed;
+  malformed << "" << "" << "" << corner;
+  return malformed;
+}
+
+std::string Overlay::getRenderedTopLeft(std::string filename) {
+  return renderString(topLeftTemplate, filename);
+}
+std::string Overlay::getRenderedTopRight(std::string filename) {
+  return renderString(topRightTemplate, filename);
+}
+std::string Overlay::getRenderedBottomLeft(std::string filename) {
+  return renderString(bottomLeftTemplate, filename);
+}
+std::string Overlay::getRenderedBottomRight(std::string filename) {
+  return renderString(bottomRightTemplate, filename);
+}
+
+int Overlay::getMarginTopLeft() {return topLeftMargin;}
+int Overlay::getFontsizeTopLeft() {return topLeftFontsize;}
+int Overlay::getMarginTopRight() {return topRightMargin;}
+int Overlay::getFontsizeTopRight() {return topRightFontsize;}
+int Overlay::getMarginBottomLeft() {return bottomLeftMargin;}
+int Overlay::getFontsizeBottomLeft() {return bottomLeftFontsize;}
+int Overlay::getMarginBottomRight() {return bottomRightMargin;}
+int Overlay::getFontsizeBottomRight() {return bottomRightFontsize;}
+
+std::string Overlay::renderString(QString overlayTemplate, std::string filename) {
+  QString result = overlayTemplate;
+  result.replace("<datetime>", QLocale::system().toString(QDateTime::currentDateTime()));
+  result.replace("<date>", QLocale::system().toString(QDate::currentDate()));
+  result.replace("<time>", QTime::currentTime().toString("hh:mm"));
+  result.replace("<filename>", filename.c_str());
+  result.replace("<exifdatetime>", getExifDate(filename));
+  return result.toStdString();
+}
+
+QString Overlay::getExifDate(std::string filename) {
+
+  QString dateTime;
+  ExifData *exifData = exif_data_new_from_file(filename.c_str());
+  if (exifData)
+  {
+    ExifEntry *exifEntry = exif_data_get_entry(exifData, EXIF_TAG_DATE_TIME_ORIGINAL);
+
+    if (exifEntry)
+    {
+      char buf[2048];
+      dateTime = exif_entry_get_value(exifEntry, buf, sizeof(buf));
+    }
+    exif_data_free(exifData);
+    QString exifDateFormat = "yyyy:MM:dd hh:mm:ss";
+    QDateTime exifDateTime = QDateTime::fromString(dateTime, exifDateFormat);
+    return QLocale::system().toString(exifDateTime);
+  }
+  return dateTime;
+}
diff --git a/src/overlay.h b/src/overlay.h
new file mode 100644
index 0000000..6fb90a6
--- /dev/null
+++ b/src/overlay.h
@@ -0,0 +1,60 @@
+#ifndef OVERLAY_H
+#define OVERLAY_H
+
+#include <iostream>
+#include <QDir>
+#include <iostream>
+#include <QString>
+#include <QStringList>
+
+class MainWindow;
+class Overlay
+{
+  public:
+    Overlay(const std::string path);
+    virtual ~Overlay();
+    std::string getRenderedTopLeft(std::string filename);
+    std::string getRenderedTopRight(std::string filename);
+    std::string getRenderedBottomLeft(std::string filename);
+    std::string getRenderedBottomRight(std::string filename);
+
+    int getMarginTopLeft();
+    int getFontsizeTopLeft();
+    int getMarginTopRight();
+    int getFontsizeTopRight();
+    int getMarginBottomLeft();
+    int getFontsizeBottomLeft();
+    int getMarginBottomRight();
+    int getFontsizeBottomRight();
+
+
+  private:
+    const std::string overlayInput;
+    int margin;
+    int fontsize;
+
+    QString topLeftTemplate;
+    QString topRightTemplate;
+    QString bottomLeftTemplate;
+    QString bottomRightTemplate;
+
+    int topLeftMargin;
+    int topRightMargin;
+    int bottomLeftMargin;
+    int bottomRightMargin;
+
+    int topLeftFontsize;
+    int topRightFontsize;
+    int bottomLeftFontsize;
+    int bottomRightFontsize;
+
+    QStringList getOverlayComponents(QString corner);
+    int getMargin(QStringList components);
+    int getFontsize(QStringList components);
+    QString getTemplate(QStringList components);
+
+    QString getExifDate(std::string filename);
+    void parseInput();
+    std::string renderString(QString overlayTemplate, std::string filename);
+};
+#endif
diff --git a/src/slide.pro b/src/slide.pro
index 7f8c9ab..a3804b9 100644
--- a/src/slide.pro
+++ b/src/slide.pro
@@ -32,12 +32,14 @@ SOURCES += \
         mainwindow.cpp \
         imageswitcher.cpp \
         pathtraverser.cpp \
+        overlay.cpp \
     imageselector.cpp
 
 HEADERS += \
         mainwindow.h \
         imageselector.h \
         pathtraverser.h \
+        overlay.h \
     imageswitcher.h
 
 FORMS += \