Downsize MB is now user-configurable

Probably doesn't matter most of the time since we resize down HEIC and PNG anyway...

Closes #7

src/Models/Settings.cs

@@ -15,6 +15,7 @@ class Settings : ChangeNotifier
     private bool _useDocnetPDFImageRendering;
     private bool _saveOutputPdfInWorkingDir;
     private string _outputPdfDir;
+    private decimal _imageResizeThreshold;
 
     public Settings()
     {
@@ -22,6 +23,7 @@ class Settings : ChangeNotifier
         _useDocnetPDFImageRendering = true;
         _saveOutputPdfInWorkingDir = true;
         _outputPdfDir = "";
+        _imageResizeThreshold = 1.5m;
     }
 
     public Settings(Settings other)
@@ -30,6 +32,7 @@ class Settings : ChangeNotifier
         _useDocnetPDFImageRendering = other.UseDocnetPDFImageRendering;
         _saveOutputPdfInWorkingDir = other.SaveOutputPdfInWorkingDir;
         _outputPdfDir = other.OutputPdfDir;
+        _imageResizeThreshold = other.ImageResizeThreshold;
     }
 
     [JsonInclude]
@@ -61,6 +64,13 @@ class Settings : ChangeNotifier
         set { _outputPdfDir = value; NotifyPropertyChanged(); }
     }
 
+    [JsonInclude]
+    public decimal ImageResizeThreshold
+    {
+        get => _imageResizeThreshold;
+        set { _imageResizeThreshold = value; NotifyPropertyChanged(); }
+    }
+
     public static string GetSettingsFileName()
     {
         return "settings.json";

src/ViewModels/MainViewModel.cs

@@ -706,7 +706,7 @@ class MainViewModel : BaseViewModel, IFontResolver, ICanCheckShutdown
                     didAdjust = true;
                 }
                 // perform needed image manipulations
-                if (isHEIC || isWebp || isPNG || (!isPDF && info.Length > 1.5 * 1024 * 1024 /* 1.5 MB */))
+                if (isHEIC || isWebp || isPNG || (!isPDF && info.Length > _settings.ImageResizeThreshold * 1024 * 1024))
                 {
                     // Save image as jpg
                     mImage.Quality = 80;

src/ViewModels/SettingsViewModel.cs

@@ -87,6 +87,16 @@ class SettingsViewModel: ChangeNotifier
         }
     }
 
+    public decimal ImageResizeThreshold
+    {
+        get => _settings.ImageResizeThreshold;
+        set
+        {
+            _settings.ImageResizeThreshold = value;
+            NotifyPropertyChanged(nameof(ImageResizeThreshold));
+        }
+    }
+
     public async void ChooseOutputFolder()
     {
         var topLevel = _topLevelGrabber?.GetTopLevel();

src/Views/SettingsView.axaml

@@ -9,7 +9,7 @@
              xmlns:models="clr-namespace:MayShow.Models"
              xmlns:vm="clr-namespace:MayShow.ViewModels"
              x:DataType="vm:SettingsViewModel"
-             MaxWidth="350">
+             MaxWidth="450">
     <ScrollViewer AllowAutoHide="False">
         <StackPanel Orientation="Vertical"
                     Spacing="8"
@@ -18,6 +18,19 @@
                     HorizontalAlignment="Center"
                     FontSize="16"
                     FontWeight="Bold" />
+            <TextBlock TextWrapping="Wrap"
+                       HorizontalAlignment="Left"
+                       Width="300">
+                Always reduce size of images if above this file size in megabytes (MB):
+            </TextBlock>
+            <NumericUpDown Value="{Binding ImageResizeThreshold}"
+                           Increment="0.1"
+                           Minimum="0.5"
+                           FormatString="0.00"
+                           Maximum="10"
+                           Width="150"
+                           HorizontalAlignment="Left"
+                           Margin="0,0,0,4" />
             <CheckBox IsChecked="{Binding !UseDocnetPDFImageRendering}">Use legacy PDF handling (does not work with macOS annotations)</CheckBox>
             <CheckBox IsChecked="{Binding SaveOutputPdfInWorkingDir}">Always save report PDF in working directory</CheckBox>
             <Grid ColumnDefinitions="*, *"