import tensorflow as tf

        output = model.build_server_graph(FLAGS, input_image)
        output = (output + 1.) * 127.5
        output = tf.reverse(output, [-1])
        output = tf.saturate_cast(output, tf.uint8)
        # load pretrained model
        vars_list = tf.get_collection(tf.GraphKeys.GLOBAL_VARIABLES)
        assign_ops = []
        for var in vars_list:
            vname = var.name
            from_name = vname
            var_value = tf.contrib.framework.load_variable(checkpoint_dir, from_name)
            assign_ops.append(tf.assign(var, var_value))
        sess.run(assign_ops)
        result = sess.run(output)
    tf.reset_default_graph()
    return result[0][:, :, ::-1]
