Add Filter that (not yet!) subtracts background

render-app/src/main/java/org/janelia/alignment/filter/AverageBackgroundSubtraction.java

@@ -0,0 +1,54 @@
+package org.janelia.alignment.filter;
+
+import ij.process.ImageProcessor;
+import mpicbg.trakem2.transform.TransformMeshMappingWithMasks;
+import org.janelia.alignment.loader.ImageLoader;
+import org.janelia.alignment.util.ImageProcessorCache;
+
+import java.util.HashMap;
+import java.util.Map;
+
+public class AverageBackgroundSubtraction implements Filter {
+	private static final ImageProcessorCache cache =
+			new ImageProcessorCache(ImageProcessorCache.DEFAULT_MAX_CACHED_PIXELS, false, false);
+
+	private String backgroundPath;
+	private double backgroundScale;
+	private float offset;
+
+	// empty constructor required to create instances from specifications
+	@SuppressWarnings("unused")
+	public AverageBackgroundSubtraction() {
+		this(null, 1.0, 0.0f);
+	}
+
+	public AverageBackgroundSubtraction(final String backgroundPath, final double backgroundScale, final float offset) {
+		this.backgroundPath = backgroundPath;
+		this.backgroundScale = backgroundScale;
+		this.offset = offset;
+	}
+
+	@Override
+	public void init(final Map<String, String> params) {
+		this.backgroundPath = Filter.getStringParameter("path", params);
+		this.backgroundScale = Filter.getDoubleParameter("scale", params);
+		this.offset = Filter.getFloatParameter("offset", params);
+	}
+
+	@Override
+	public Map<String, String> toParametersMap() {
+		final Map<String, String> map = new HashMap<>();
+		map.put("path", backgroundPath);
+		map.put("scale", String.valueOf(backgroundScale));
+		map.put("offset", String.valueOf(offset));
+		return map;
+	}
+
+	@Override
+	public void process(final ImageProcessor ip, final double scale) {
+		final ImageProcessor background = cache.get(backgroundPath, 0, false, false, ImageLoader.LoaderType.IMAGEJ_DEFAULT, null);
+
+
+
+	}
+}