Local Voice Data Processing

A system comprising a microcontroller unit (MCU), the MCU comprising:

• at least one microphone;
• a network interface;
• at least one processor;
• at least one tangible, non-transitory computer-readable medium;
• and
• program instructions stored on the at least one tangible, non-transitory computer-readable medium that, when executed by the at least one processor, cause the MCU to perform functions comprising:
• storing, in memory of the MCU, data representing a set of local keywords comprising (a) first keywords corresponding to one or more media playback system commands and (b) second keywords corresponding to one or more smart appliance commands;
• capturing a first voice input via the at least one microphone, wherein capturing the first voice input comprises buffering first voice data;
• determining that one or more uttered keywords in the captured first voice input are not in the set of local keywords stored in the memory of the MCU;
• in response to the determining, sending, via the network interface, data representing the first voice input to a playback device for processing of the first voice input;
• capturing a second voice input via the at least one microphone, wherein capturing the second voice input comprises buffering second voice data;
• processing the second voice input, wherein processing the second voice input comprises matching portions of the second voice input to at least one particular first keyword corresponding to at least one first media playback system command;
• and
• causing, via the network interface, a group of one or more playback devices to carry out the at least one first media playback system command.

A system comprising a first playback device and a second playback device, the first playback device comprising:

• at least one first microphone;
• a first network interface;
• at least one first processor;
• at least one first tangible, non-transitory computer-readable medium;
• and
• first program instructions stored on the at least one first tangible, non-transitory computer-readable medium that, when executed by the at least one first processor, cause the first playback device to perform first functions comprising:
• storing, in memory of the first playback device, data representing a first set of local keywords comprising (a) first keywords corresponding to one or more media playback system commands and (b) second keywords corresponding to one or more contextual commands;
• capturing a first voice input via the at least one first microphone, wherein capturing the first voice input comprises buffering first voice data;
• determining that one or more uttered keywords in the captured first voice input are not in the first set of local keywords stored in the memory of the first playback device;
• in response to the determining, sending, via the first network interface, data representing the first voice input to the second playback device;
• capturing a second voice input via the at least one first microphone, wherein capturing the second voice input comprises buffering second voice data;
• processing the second voice input, wherein processing the second voice input comprises matching portions of the second voice input to at least one particular first keyword corresponding to at least one first media playback system command;
• and
• causing, via the first network interface, a group of one or more playback devices to carry out the at least one first media playback system command;
• and
• the second playback device comprising:
• at least one second microphone;
• a second network interface;
• at least one second processor;
• at least one second tangible, non-transitory computer-readable medium;
• and
• second program instructions stored on the at least one second tangible, non-transitory computer-readable medium that, when executed by the at least one second processor, cause the second playback device to perform second functions comprising:
• storing, in memory of the second playback device, data representing a second set of local keywords comprising (a) the first keywords and (b) third keywords corresponding to one or more additional media playback system commands;
• receiving, via the second network interface, the data representing the first voice input;
• processing the first voice input, wherein processing the first voice input comprises matching portions of the first voice input to at least one particular third keyword corresponding to at least one additional media playback system command;
• and
• causing, via the second network interface, the group of one or more playback devices to carry out the at least one additional media playback system command.