What is the primary mechanism that allows visual microphones to recover sound?

• By detecting vibrations in objects caused by sound.

• By amplifying sound waves directly from the air.

• By using microphones embedded in the objects.

• By converting light signals into sound.

In the experiment with the potted plant, why were the vibrations caused by the music difficult to see with the naked eye?

• The vibrations were too fast for the human eye to detect.

• The plant's leaves were too small to move significantly.

• The camera used was not sensitive enough to capture the motion.

• The vibrations moved the leaves by less than a hundredth of a pixel.

What additional challenge was introduced in the experiment with the bag of chips?

• The sound source was placed farther away.

• The video was recorded at a lower frame rate.

• The object was made of a material that absorbed sound.

• The camera was placed outside behind a soundproof window.

How was the song played through the earbuds identified in the experiment?

• By comparing the vibrations to a database of songs.

• By using audio recognition software.

• By analyzing the frequency spectrum of the sound.

• By manually listening to the recovered sound.

How does the rolling shutter effect in consumer cameras help in recovering sound?

• It enhances the resolution of the captured video.

• It introduces artifacts that can encode higher frequency vibrations.

• It increases the frame rate of the video.

• It stabilizes the video to reduce noise.