Voice trigger for a digital assistant

A non-transitory computer-readable storage medium, storing one or more programs for execution by one or more processors of an electronic device, the one or more programs including instructions for:

• determining, based on comparing an amount of light detected on at least a front surface of the electronic device to a threshold amount of light, whether to operate a voice trigger in a standby mode or in a listening mode;
• in accordance with a determination to operate the voice trigger in the listening mode:
• receiving a sound input;
• generating an input representation of the sound input, wherein the input representation represents audio signatures of the sound input;
• determining whether at least a portion of the sound input corresponds to a predetermined type of sound;
• upon a determination that at least a portion of the sound input corresponds to the predetermined type, determining whether the sound input includes predetermined content based on comparing of the input representation of the sound input to one or more reference representations;
• upon a determination that the sound input includes the predetermined content, generating a control signal comprising instructions to initiate a speech based service;
• and
• initiating the speech-based service based on the control signal;
• and
• in accordance with a determination to operate the voice trigger in the standby mode, forgoing initiating the speech-based service based on received sound input.

An electronic device, comprising:

• a sound receiving unit configured to receive sound input;
• and
• a processing unit coupled to the sound receiving unit, the processing unit configured to:
• determine, based on comparing an amount of light detected on at least a front surface of the electronic device to a threshold amount of light, whether to operate a voice trigger in a standby mode or in a listening mode;
• in accordance with a determination to operate the voice trigger in the listening mode:
• generate an input representation of the sound input, wherein the input representation represents audio signatures of the sound input;
• determine whether at least a portion of the sound input corresponds to a predetermined type of sound;
• upon a determination that at least a portion of the sound input corresponds to the predetermined type, determine whether the sound input includes predetermined content based on comparing of the input representation of the sound input to one or more reference representations;
• upon a determination that the sound input includes the predetermined content, generate a control signal comprising instructions to initiate a speech-based service;
• and
• initiate the speech-based service based on the control signal;
• and
• in accordance with a determination to operate the voice trigger in the standby mode, forgo initiating the speech-based service based on received sound input.