A real-time speech command detector for a smart control room

In this work we present an online ASR system that is able to discriminate voice commands directed to an operationable screen from irrelevant speech segments. For classification of the sound segments we explored several features that are based on prosody as well as properties generated during the decoding process. For a vocabulary of 259 words and more than 10k possible commands, our realtime Verbal Command Detector managed to detect 88.3% of the commands in our evaluation data while maintaining a low False Positive Rate (FPR) of 1.5%. On an evaluation task using an episode of Star Trek, our system was able to detect 91.2% of all commands with a FPR of 1.8% with only minor adjustments. The system is part of and used in the Smart Control Room at the Fraunhofer IOSB in Karlsruhe [1], an experimental smart environment that uses multiple input modalities for crisis response.