ADD: uDarwinImageUtil on macOS

src/doublecmd.lpi

@@ -332,7 +332,7 @@ end;"/>
         <PackageName Value="Image32"/>
       </Item13>
     </RequiredPackages>
-    <Units Count="293">
+    <Units Count="294">
       <Unit0>
         <Filename Value="doublecmd.lpr"/>
         <IsPartOfProject Value="True"/>
@@ -2129,6 +2129,11 @@ end;"/>
         <IsPartOfProject Value="True"/>
         <UnitName Value="uDarwinFileUtil"/>
       </Unit292>
+      <Unit293>
+        <Filename Value="platform\unix\darwin\udarwinimageutil.pas"/>
+        <IsPartOfProject Value="True"/>
+        <UnitName Value="uDarwinImageUtil"/>
+      </Unit293>
     </Units>
   </ProjectOptions>
   <CompilerOptions>

src/platform/unix/darwin/udarwinimageutil.pas

@@ -0,0 +1,51 @@
+unit uDarwinImageUtil;
+
+{$mode delphi}
+{$modeswitch objectivec2}
+
+interface
+
+uses
+  Classes, SysUtils,
+  CocoaAll, CocoaUtils;
+
+type
+  
+  { TDarwinImageUtil }
+
+  TDarwinImageUtil = class
+  public
+    class function filt( const filterName: NSString; const sourceImage: NSImage ): NSImage;
+    class function invertColor( const sourceImage: NSImage ): NSImage;
+  end;
+
+implementation
+
+class function TDarwinImageUtil.filt(
+  const filterName: NSString;
+  const sourceImage: NSImage ): NSImage;
+var
+  tiffData: NSData;
+  inputImage: CIImage;
+  outputImage: CIImage;
+  filter: CIFilter;
+  rep: NSCIImageRep;
+begin
+  tiffData:= sourceImage.TIFFRepresentation;
+  inputImage:= CIImage.imageWithData( tiffData );
+  filter:= CIFilter.filterWithName( filterName );
+  filter.setValue_forKey( inputImage, kCIInputImageKey );
+  outputImage:= filter.valueForKey( kCIOutputImageKey );
+  rep:= NSCIImageRep.imageRepWithCIImage( outputImage );
+  Result:= NSImage.alloc.initWithSize( sourceImage.size );
+  Result.addRepresentation( rep );
+  Result.autorelease;
+end;
+
+class function TDarwinImageUtil.invertColor( const sourceImage: NSImage ): NSImage;
+begin
+  Result:= filt( NSSTR('CIColorInvert'), sourceImage );
+end;
+
+end.
+