Command analysis device, command analysis method, and program

A command analysis method performed by a command analysis device, the command analysis method comprising:

• retrieving a final result recognition rule from a final result recognition rule storage, a first intermediate result recognition rule from a first intermediate result recognition rule storage, and a second intermediate result recognition result from the second intermediate recognition result storage, wherein the first intermediate result recognition rule, the second intermediate result recognition rule, and the final result recognition rule are predetermined and are mutually distinct;
• performing, every time when a predetermined unit of a speech signal is input, speech recognition on the speech signal and acquiring a partial speech recognition result which is a first intermediate result, wherein the performing further comprises:
• determining whether the partial speech recognition result includes an end of a sentence, and outputting the speech recognition result, which is a final result, and an end-of-sentence signal when the end of a sentence is included;
• determining, when the partial speech recognition result does not include the end of a sentence, whether a silence interval has continued for a predetermined period of time or more, or whether a new instance of the speech recognition result has not been acquired for a predetermined period of time or more, and output a silence signal when the silence interval has continued for the predetermined period of time or more or when a new instance of the speech recognition result has not been acquired for a predetermined period of time or more,
• switching the first intermediate result recognition rule to the second intermediate result recognition rule upon receiving the silence signal, wherein the second intermediate result recognition rule allows commands to be analyzed even when the speech signal is interrupted at a point other than the end of a sentence, and
• switching the first intermediate result recognition rule to the final result recognition rule, upon receiving the end-of-sentence signal, the final result recognition rule does not identify the command while the speech recognition is in progress;
• verifying the first intermediate result using the first intermediate result recognition rule to parse a command in the speech signal according to the speech recognition, wherein the first intermediate result recognition rule includes recognizing the command before the speech signal reaches an end of a sentence, wherein the verifying further comprises:
• verifying the intermediate result in light of the second intermediate result recognition rule when the intermediate result recognition rule is switched to the second intermediate result recognition rule, and
• verifying the final result in light of the final result recognition rule when the intermediate result recognition rule is switched to the final result recognition rule;
• and
• when a command execution target and a command execution content are successfully analyzed, outputting an analysis result during the input of the speech signal, wherein the analysis result indicates a type of the command conveyed by the speech signal.