Add an option to blur background image.

Fixes issue 3266.

src/playlist/playlistview.cpp

@@ -1017,16 +1017,19 @@ void PlaylistView::ReloadSettings() {
     }
   }
   QString background_image_filename = s.value(kSettingBackgroundImageFilename).toString();
+  int blur_radius = s.value("blur_radius").toInt();
   // Check if background properties have changed.
   // We change properties only if they have actually changed, to avoid to call
   // set_background_image when it is not needed, as this will cause the fading
   // animation to start again. This also avoid to do useless
   // "force_background_redraw".
   if (background_image_filename != background_image_filename_
-      || background_type != background_image_type_) {
+      || background_type != background_image_type_ || 
+      blur_radius_ != blur_radius) {
     // Store background properties
     background_image_type_ = background_type;
     background_image_filename_ = background_image_filename;
+    blur_radius_ = blur_radius;
     if (background_image_type_ == Custom) {
       set_background_image(QImage(background_image_filename));
     } else if (background_image_type_ == AlbumCover) {
@@ -1190,18 +1193,93 @@ void PlaylistView::set_background_image(const QImage& image) {
   else
     background_image_ = image;
 
+
+
   // Apply opacity filter
   uchar* bits = background_image_.bits();
   for (int i = 0; i < background_image_.height() * background_image_.bytesPerLine(); i+=4) {
     bits[i+3] = kBackgroundOpacity * 255;
   }
 
+  if (blur_radius_ != 0) 
+    background_image_ = blur_background_image(background_image_, blur_radius_, false);
+
   if (isVisible()) {
     previous_background_image_opacity_ = 1.0;
     fade_animation_->start();
   }
 }
 
+
+QImage PlaylistView::blur_background_image(const QImage& image, int radius, bool alphaOnly = false)
+{
+  int tab[] = { 14, 10, 8, 6, 5, 5, 4, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2 };
+  int alpha = (radius < 1)  ? 16 : (radius > 17) ? 1 : tab[radius-1];
+
+  QImage result = image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
+  QRect rect = image.rect();
+  int r1 = rect.top();
+  int r2 = rect.bottom();
+  int c1 = rect.left();
+  int c2 = rect.right();
+
+  int bpl = result.bytesPerLine();
+  int rgba[4];
+  unsigned char* p;
+
+  int i1 = 0;
+  int i2 = 3;
+
+  if (alphaOnly)
+    i1 = i2 = (QSysInfo::ByteOrder == QSysInfo::BigEndian ? 0 : 3);
+
+  for (int col = c1; col <= c2; col++) {
+    p = result.scanLine(r1) + col * 4;
+    for (int i = i1; i <= i2; i++)
+      rgba[i] = p[i] << 4;
+
+    p += bpl;
+    for (int j = r1; j < r2; j++, p += bpl)
+      for (int i = i1; i <= i2; i++)
+	p[i] = (rgba[i] += ((p[i] << 4) - rgba[i]) * alpha / 16) >> 4;
+  }
+
+  for (int row = r1; row <= r2; row++) {
+    p = result.scanLine(row) + c1 * 4;
+    for (int i = i1; i <= i2; i++)
+      rgba[i] = p[i] << 4;
+
+    p += 4;
+    for (int j = c1; j < c2; j++, p += 4)
+      for (int i = i1; i <= i2; i++)
+	p[i] = (rgba[i] += ((p[i] << 4) - rgba[i]) * alpha / 16) >> 4;
+  }
+
+  for (int col = c1; col <= c2; col++) {
+    p = result.scanLine(r2) + col * 4;
+    for (int i = i1; i <= i2; i++)
+      rgba[i] = p[i] << 4;
+
+    p -= bpl;
+    for (int j = r1; j < r2; j++, p -= bpl)
+      for (int i = i1; i <= i2; i++)
+	p[i] = (rgba[i] += ((p[i] << 4) - rgba[i]) * alpha / 16) >> 4;
+  }
+
+  for (int row = r1; row <= r2; row++) {
+    p = result.scanLine(row) + c2 * 4;
+    for (int i = i1; i <= i2; i++)
+      rgba[i] = p[i] << 4;
+
+    p -= 4;
+    for (int j = c1; j < c2; j++, p -= 4)
+      for (int i = i1; i <= i2; i++)
+	p[i] = (rgba[i] += ((p[i] << 4) - rgba[i]) * alpha / 16) >> 4;
+  }
+
+  return result;
+}
+
 void PlaylistView::FadePreviousBackgroundImage(qreal value) {
   previous_background_image_opacity_ = value;
   if (qFuzzyCompare(previous_background_image_opacity_, qreal(0.0))) {

src/playlist/playlistview.h

@@ -73,6 +73,7 @@ class PlaylistView : public QTreeView {
   // Constants for settings: are persistent, values should not be changed
   static const char* kSettingBackgroundImageType;
   static const char* kSettingBackgroundImageFilename;
+  static const int kSettingBackgroundBlurLevel;
 
   static ColumnAlignmentMap DefaultColumnAlignment();
 
@@ -166,6 +167,7 @@ class PlaylistView : public QTreeView {
   // Save image as the background_image_ after applying some modifications (opacity, ...).
   // Should be used instead of modifying background_image_ directly
   void set_background_image(const QImage& image);
+  QImage blur_background_image(const QImage& image, int radius, bool alphaOnly);
 
  private:
   static const int kGlowIntensitySteps;
@@ -173,7 +175,7 @@ class PlaylistView : public QTreeView {
   static const int kDropIndicatorWidth;
   static const int kDropIndicatorGradientWidth;
   static const qreal kBackgroundOpacity;
-
+  
   QList<int> GetEditableColumns();
   QModelIndex NextEditableIndex(const QModelIndex& current);
   QModelIndex PrevEditableIndex(const QModelIndex& current);
@@ -194,6 +196,7 @@ class PlaylistView : public QTreeView {
   // particular (in terms of format, opacity), you should probably use
   // set_background_image_type instead of modifying background_image_ directly
   QImage background_image_;
+  int blur_radius_;
   // Used if background image is a filemane
   QString background_image_filename_;
   QImage current_song_cover_art_;

src/ui/appearancesettingspage.cpp

@@ -56,6 +56,7 @@ AppearanceSettingsPage::AppearanceSettingsPage(SettingsDialog* dialog)
   connect(ui_->select_foreground_color, SIGNAL(pressed()), SLOT(SelectForegroundColor()));
   connect(ui_->select_background_color, SIGNAL(pressed()), SLOT(SelectBackgroundColor()));
   connect(ui_->use_a_custom_color_set, SIGNAL(toggled(bool)), SLOT(UseCustomColorSetOptionChanged(bool)));
+  connect(ui_->blur_slider, SIGNAL(valueChanged(int)), SLOT(BlurLevelChanged(int)));
 
   connect(ui_->select_background_image_filename_button, SIGNAL(pressed()), SLOT(SelectBackgroundImage()));
   connect(ui_->use_custom_background_image, SIGNAL(toggled(bool)),
@@ -114,6 +115,7 @@ void AppearanceSettingsPage::Load() {
       ui_->use_default_background->setChecked(true);
   }
   ui_->background_image_filename->setText(playlist_view_background_image_filename_);
+  
   s.endGroup();
 
   // Moodbar settings
@@ -154,7 +156,8 @@ void AppearanceSettingsPage::Save() {
         playlist_view_background_image_filename_);
   }
   s.setValue(PlaylistView::kSettingBackgroundImageType,
-      playlist_view_background_image_type_);
+	     playlist_view_background_image_type_);
+  s.setValue("blur_radius", ui_->blur_slider->value());
   s.endGroup();
 
   // Moodbar settings
@@ -230,6 +233,12 @@ void AppearanceSettingsPage::SelectBackgroundImage() {
   ui_->background_image_filename->setText(playlist_view_background_image_filename_);
 }
 
+void AppearanceSettingsPage::BlurLevelChanged(int value) {
+  background_blur_radius_ = value;
+  ui_->background_blur_radius_label->setText(QString("%1px").arg(value));
+  
+}
+
 void AppearanceSettingsPage::InitMoodbarPreviews() {
 #ifdef HAVE_MOODBAR
   if (initialised_moodbar_previews_)

src/ui/appearancesettingspage.h

@@ -42,6 +42,7 @@ private slots:
   void SelectBackgroundColor();
   void UseCustomColorSetOptionChanged(bool);
   void SelectBackgroundImage();
+  void BlurLevelChanged(int);
 
 private:
   static const int kMoodbarPreviewWidth;
@@ -62,7 +63,8 @@ private:
   QColor current_background_color_;
   PlaylistView::BackgroundImageType playlist_view_background_image_type_;
   QString playlist_view_background_image_filename_;
-
+  int background_blur_radius_;
+ 
   bool initialised_moodbar_previews_;
 };
 

src/ui/appearancesettingspage.ui

@@ -155,6 +155,52 @@
         </item>
        </layout>
       </item>
+      <item>
+       <layout class="QHBoxLayout" name="horizontalLayout_6">
+        <item>
+         <widget class="QLabel" name="select_background_blur_label">
+          <property name="enabled">
+           <bool>true</bool>
+          </property>
+          <property name="text">
+           <string>Select blur radius:</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QLabel" name="background_blur_radius_label">
+          <property name="enabled">
+           <bool>true</bool>
+          </property>
+          <property name="text">
+           <string>0px</string>
+          </property>
+         </widget>
+        </item>
+        <item>
+         <widget class="QSlider" name="blur_slider">
+          <property name="minimum">
+           <number>0</number>
+          </property>
+          <property name="maximum">
+           <number>10</number>
+          </property>
+          <property name="value">
+           <number>0</number>
+          </property>
+          <property name="orientation">
+           <enum>Qt::Horizontal</enum>
+          </property>
+          <property name="tickPosition">
+           <enum>QSlider::TicksBelow</enum>
+          </property>
+          <property name="tickInterval">
+           <number>1</number>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
      </layout>
     </widget>
    </item>