Siri sucks to use in public.
Think about it: whether you're in a library or a grocery store, it's awkward to use Siri. She's loud. But, imagine if she could whisper. Would you use it more then? Apple seems to be asking itself this very question, according to its patent application, which Gizmodo just discovered. The patent describes an assistant capable of whispering.
Apple filed for the patent last year, and the US Patent and Trademark Office has just made it public. It details “a digital assistant that is capable of detecting a whispered speech input and providing a whispered speech response”. It also admits that Siri usually responds in a "loud voice", which may be "undesired under certain circumstances".
Apple provided a few instances of when a whispered response from Siri may be more appropriate, like at the library or in a cubicle at work. Anyway, if this patent ever comes to fruition, it means that you might one day be able to whisper to Siri and have the assistant whisper responses back to you, thus protecting your privacy a bit more.
As for the actual technology, the filing discusses how a Siri-enabled device, like an iPhone, will measure an audio input’s amplitude and frequency patterns and then determine if you're whispering.
Check it out: