What is different from the past? Wireless music & video new experience
To put it simply, it is a streaming technology that distributes audio and videos on iOS/MacOS devices to other devices via a network.Before proceeding to the successor to AirPlay 2, I would like to look back on the flow of AirPlay.
First, AirPlay has the predecessor called "AirTunes".It was the first voice streaming standard for "AirMac Express" released in 2004 ("Airport Express"), and was renamed "AirPlay" when a video streaming was added.
AirPlayの原型となるAirTunesを採用した2004年の「AirMac Express」
AirMac Express is a small Wi-Fi router integrated with the AC power plug.Ethernet and Wi-Fi (IEEE 802.In addition to corresponding to 11a/b/g), receiving sound data sent from iTunes 3.It had a function to output to 5mm jack.This jack is both analog/digital, and when a stereo mini cable is connected, the internal DAC chip has an analog output, and a digital output can be made by connecting an optical digital cable.
AIRTUNES is the standard provided for the transmission of the sound data.Songs such as WAVs (the use of the Mac/Windows version of iTunes were kept in mind), were transmitted to AirMac Express, converted to the reverse compression audio codec "Apple Lossless"..It is an analog/digital output from a 5mm jack.The upper limit of the corresponding sampling rate/bit depth is 44.Audio fans were also focused on 1kHz/16bit, as a technology that could wirelessly and loseless transmission of CD sounds.
Another point is that we supported the zero configuration technology "Rendezvous".If you connect to the network, the IP address will be assigned automatically, enabling communication with other devices, making it much easier to introduce.The mechanism that can easily select AirMac Express as an iTunes audio output destination is Rendezvous.
However, AirTunes was not licensed by other companies.Speaking of 2004, when the iPod was gaining popularity, Apple focused on the music business, including the world expansion of the iTunes Music Store.It is also enthusiastic about building a music playback environment centered on the iPod, and the iPod Hi-Fi, which has a Dock at the top, is one of the products that makes you feel that attitude.At that time, the songs sold on the iTunes Music Store were DRM (FairPlay), and it was a reasonable era even if AirTunes was devised as a sound protocol for Apple products.