Pass Tensorflow serving params when calling a model

{
        "instances": [{
            "image": {
                "type": "img",
                "b64": "aW1hZ2UgYnl0ZXM="
            },
            "dc:title": {
                "type": "txt",
                "text": "my title"
            },
            "dc:created": {
                "type": "cat",
                "categories": ["4943920348"]
            }
        }]
    }