diff --git a/base/source/java/ch/systemsx/cisd/base/image/IStreamingImageTransformerFactory.java b/base/source/java/ch/systemsx/cisd/base/image/IStreamingImageTransformerFactory.java
index 61c481a8dd5597a61a306ac995f0d7e338de0bc7..6b4e06f561e1534c79f6a995c37dde8ea4d233f8 100644
--- a/base/source/java/ch/systemsx/cisd/base/image/IStreamingImageTransformerFactory.java
+++ b/base/source/java/ch/systemsx/cisd/base/image/IStreamingImageTransformerFactory.java
@@ -16,6 +16,7 @@
 
 package ch.systemsx.cisd.base.image;
 
+import ch.systemsx.cisd.base.annotation.JsonObject;
 import ch.systemsx.cisd.base.image.IImageTransformerFactory;
 
 /**
@@ -24,6 +25,7 @@ import ch.systemsx.cisd.base.image.IImageTransformerFactory;
  * 
  * @author Bernd Rinn
  */
+@JsonObject(value="IStreamingImageTransformerFactory")
 public interface IStreamingImageTransformerFactory extends IImageTransformerFactory
 {
     /**
diff --git a/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/transformations/ConvertToolImageTransformer.java b/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/transformations/ConvertToolImageTransformer.java
index 9c061da84106894e4e64e2ee581ba8de67016789..2e4d7a056c783d6ee0a70fce3d33c28993f1f4ef 100644
--- a/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/transformations/ConvertToolImageTransformer.java
+++ b/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/transformations/ConvertToolImageTransformer.java
@@ -32,6 +32,7 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.log4j.Logger;
 
+import ch.systemsx.cisd.base.annotation.JsonObject;
 import ch.systemsx.cisd.base.exceptions.CheckedExceptionTunnel;
 import ch.systemsx.cisd.base.image.IStreamingImageTransformer;
 import ch.systemsx.cisd.base.utilities.OSUtilities;
@@ -55,6 +56,7 @@ import ch.systemsx.cisd.openbis.dss.generic.shared.utils.ImageUtil;
  * 
  * @author Kaloyan Enimanev
  */
+@JsonObject(value="ConvertToolImageTransformer")
 public class ConvertToolImageTransformer implements IStreamingImageTransformer
 {
 
diff --git a/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/v1/transformations/ConvertToolImageTransformer.java b/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/v1/transformations/ConvertToolImageTransformer.java
index 51e8ca6a3ae5705456baee1395d0fe6aca71ab30..7889caaf29fe3dcd855585de92e8deef5382561a 100644
--- a/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/v1/transformations/ConvertToolImageTransformer.java
+++ b/screening/source/java/ch/systemsx/cisd/openbis/dss/etl/dto/api/v1/transformations/ConvertToolImageTransformer.java
@@ -16,6 +16,7 @@
 
 package ch.systemsx.cisd.openbis.dss.etl.dto.api.v1.transformations;
 
+import ch.systemsx.cisd.base.annotation.JsonObject;
 import ch.systemsx.cisd.openbis.dss.etl.dto.api.transformations.ConvertToolImageTransformerFactory.ToolChoice;
 
 /**
@@ -25,6 +26,7 @@ import ch.systemsx.cisd.openbis.dss.etl.dto.api.transformations.ConvertToolImage
  * 
  * @author Jakub Straszewski
  */
+@JsonObject(value="ConvertToolImageTransformer_obsolete")
 public class ConvertToolImageTransformer extends
         ch.systemsx.cisd.openbis.dss.etl.dto.api.transformations.ConvertToolImageTransformer
 {