Audio signal level estimation in cameras

摘要

A camera system includes a first microphone, a second microphone, and a microphone controller. The first microphone and the second microphone are configured to capture audio over a time interval to produce a first captured audio signal and a second captured audio signal, respectively. The second captured audio signal is dampened relative to the first captured audio signal by a dampening factor. The microphone controller is configured to store the first captured audio signal in response to a determination that the first captured audio signal does not clip. In response to a determination that the first captured audio signal clips, the microphone controller is configured to identify a gain between the first captured audio signal and the second captured audio signal representative of the dampening factor, amplify the second captured audio signal based on the identified gain, and store the amplified second captured audio signal.

主权项

1. A camera, comprising:
a first microphone configured to capture audio over a time interval to produce a first captured audio signal; a second microphone configured to capture audio over the time interval to produce a second captured audio signal, the second captured audio signal dampened relative to the first captured audio signal by a dampening factor; and a microphone controller coupled to the first microphone and the second microphone, the microphone controller configured to:
in response to a determination that the first captured audio signal does not clip, store the first captured audio signal; andin response to a determination that the first captured audio signal clips:
identify a first slope of the first captured audio signal at a first zero crossing of a measure of amplitude of the first captured audio signal;identify a second slope of the second captured audio signal at a second zero crossing of the measure of amplitude of the second captured audio signal, the second zero crossing corresponding to the first zero crossing;identify a gain comprising a ratio of the first slope to the second slope;amplify the second captured audio signal based on the identified gain; andstore the amplified second captured audio signal.