Data captured from the physical world through receptor devices such as wireless sensor networks and RFID readers tend to be unreliable and noisy. The data cleaning process for such data is not easily handled by standard data warehouse-oriented techniques, which do not take into account the strong temporal and spatial components of receptor data. Here we present Extensible receptor Stream Processing (ESP), an extensible framework for cleaning the data streams produced by physical receptor devices. ESP is a declarative query processing tool with a pipelined design that is easy to setup and configure for each receptor deployment. We validate the ESP platform through three real-world deployments using ESP to clean receptor data streams.