diff --git a/android/src/main/java/com/finogeeks/mop/api/mop/AppletHandlerModule.java b/android/src/main/java/com/finogeeks/mop/api/mop/AppletHandlerModule.java
index 331d2b2..edae73e 100644
--- a/android/src/main/java/com/finogeeks/mop/api/mop/AppletHandlerModule.java
+++ b/android/src/main/java/com/finogeeks/mop/api/mop/AppletHandlerModule.java
@@ -158,7 +158,7 @@ public class AppletHandlerModule extends BaseApi {
                 }.getType()));
                 if (bitmap != null) {
                     ByteArrayOutputStream baos = new ByteArrayOutputStream();
-                    bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
+                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, baos);
                     byte[] data = baos.toByteArray();
                     params.put("bitmap", data);
                 }