Here’s the care Apple takes to test iPhone video recording

CNET’s The title mentioned “A rare look inside Apple.” secret iphone 16 “Camera Lab” is a bit exaggerated because they have no secrets: we’ve seen one of them a couple previous times.

But regardless, the article does provide an interesting look at some of the testing processes used during the development of the new iPhone…

our first glance Back in 2018, Apple showed off its anechoic chamber cyclethen the second months agoApple shared the photo in an AirPods press release at the time.

Science and Technology Information Network Shows some of the ways Apple tests microphones for iPhone video recording sound (demonstration via iPhone 16).

A series of speakers (approximately two dozen) are mounted on curved ducts that extend from beneath the wire mesh floor to the ceiling of the room. The speaker emits a series of tones, and engineers measure the sound picked up by the iPhone 16 Pro’s microphone. The phone is mounted on a stand on a swivel base, and when you turn it clockwise a few degrees, the ringer will ring again. This continues until the iPhone has rotated a full circle.

The result is a spherical sound profile for each microphone based on data recorded in an anechoic chamber. Apple takes these profiles and uses them as the basis for spatial audio and other software that can reduce wind noise or make iPhone-recorded audio behave and sound like different types of microphones — think lavalier microphones for voiceovers Or a studio microphone.

“We hope to achieve this [Audio Mix] It functions just like recording with a lavalier microphone,” Dave explains. “We used machine learning algorithms along with a tuning chain to produce a signature sound that can be heard even with a lavalier microphone.”

Interestingly, while the main judgment on the results was made by the “golden ears” of Apple audio director Ruchir Dave, they also tested different mixes with regular iPhone users.

Rather than having just one hearing person adjust the iPhone’s audio, Apple has many testers perform perceptual audio tests and then uses the results to calibrate the playback you hear on your iPhone. While I was there, I even became one of these testers and went through part of the experience […]

Apple uses comparison tests like this, much like an eye doctor would ask you to choose between two different lenses in an eye test. Evaluating a recording is more challenging without something to compare the audio to. The results of the perceptual testing help influence how different aspects of iPhone 16 Pro audio work, including audio mixing.

For video testing, Apple has what it calls the Video Validation Lab—essentially a way to ensure that the end result still looks good when viewed under many different real-world conditions.

“We use this theater to tailor the video playback experience so that when you play these videos in a dark room, an office environment, or even in the sun, you get the same perceptual experience as watching the video in the theater,” said Xiao, Apple’s director of video engineering. Sean Yang told me.

The entire article doesn’t reveal any deep secrets, but it’s still an interesting look at how much thought Apple puts into these little things.

Photo: Apple