Image uploading REST APIs need to support automatic thumbnail generation

The built-in ImageSet JAX-RS service provides image uploading operations. For example,

• @POST @Path("/thumbnail/content/") @Consumes("multipart/form-data")
• @POST @Path("/original/content/") @Consumes("multipart/form-data")

However, this means REST Clients have to upload thumbnail and original image separately.
It would be great if there's an option to generate thumbnails automatically when uploading original images, as being done in CMS.