diff --git a/src/micropolisj/build_tool/MakeTiles.java b/src/micropolisj/build_tool/MakeTiles.java
index b4f1d9b..cd30195 100644
--- a/src/micropolisj/build_tool/MakeTiles.java
+++ b/src/micropolisj/build_tool/MakeTiles.java
@@ -441,13 +441,23 @@ public class MakeTiles
 
 		if (!loadedImages.containsKey(fileName)) {
 			loadedImages.put(fileName,
-				loadImageReal(fileName));
+				loadImageNoCache(fileName));
 		}
 
 		return loadedImages.get(fileName);
 	}
 
-	static SourceImage loadImageReal(String fileName)
+	static SourceImage loadImageReal(File pngFile, int basisSize)
+		throws IOException
+	{
+		BufferedImage bi = ImageIO.read(pngFile);
+		return new SourceImage(
+			bi,
+			basisSize,
+			TILE_SIZE);
+	}
+
+	static SourceImage loadImageNoCache(String fileName)
 		throws IOException
 	{
 		File svgFile, pngFile = null;
@@ -465,40 +475,24 @@ public class MakeTiles
 		}
 
 		if (pngFile != null && pngFile.exists()) {
-			ImageIcon ii = new ImageIcon(pngFile.toString());
-			return new SourceImage(
-				ii.getImage(),
-				TILE_SIZE,
-				TILE_SIZE);
+			return loadImageReal(pngFile, TILE_SIZE);
 		}
 
 		pngFile = new File(fileName+"_"+TILE_SIZE+"x"+TILE_SIZE+".png");
 		if (pngFile.exists()) {
-			ImageIcon ii = new ImageIcon(pngFile.toString());
-			return new SourceImage(
-				ii.getImage(),
-				TILE_SIZE,
-				TILE_SIZE);
+			return loadImageReal(pngFile, TILE_SIZE);
 		}
 
 		if (TILE_SIZE < 128) {
 		pngFile = new File(fileName+"_128x128.png");
 		if (pngFile.exists()) {
-			ImageIcon ii = new ImageIcon(pngFile.toString());
-			return new SourceImage(
-				ii.getImage(),
-				128,
-				TILE_SIZE);
+			return loadImageReal(pngFile, 128);
 		}
 		}
 
 		pngFile = new File(fileName+".png");
 		if (pngFile.exists()) {
-			ImageIcon ii = new ImageIcon(pngFile.toString());
-			return new SourceImage(
-				ii.getImage(),
-				STD_SIZE,
-				TILE_SIZE);
+			return loadImageReal(pngFile, STD_SIZE);
 		}
 
 		throw new IOException("File not found: "+fileName+".{svg,png}");
diff --git a/src/micropolisj/graphics/TileImage.java b/src/micropolisj/graphics/TileImage.java
index 799cc36..e6e1dbb 100644
--- a/src/micropolisj/graphics/TileImage.java
+++ b/src/micropolisj/graphics/TileImage.java
@@ -48,13 +48,16 @@ public abstract class TileImage
 		}
 	}
 
+	/**
+	 * Supports rescaling of tile images.
+	 */
 	public static class SourceImage extends TileImage
 	{
-		public final Image image;
+		public final BufferedImage image;
 		public final int basisSize;
 		public final int targetSize;
 
-		public SourceImage(Image image, int basisSize, int targetSize)
+		public SourceImage(BufferedImage image, int basisSize, int targetSize)
 		{
 			this.image = image;
 			this.basisSize = basisSize;