Do Apple Lossless tracks remain lossless when sent via Airplay to a 4th gen Apple TV?

Question

This question, from 2012, asks whether there is loss in the signal quality of an Apple-Lossless-encoded file when transmitted from a Macbook to an Airport Express.

I am wondering whether things are any different in 2016 when transmitting an Apple-Lossless-encoded file from a Macbook to a 4th gen Apple TV. Clearly Wifi is plenty able to transmit the file intact. With an HDMI connection to the TV and an Optical (audio) connection from the TV to the receiver, I should in principle be able to listen to an intact file.

1. Is it still the case in 2016 that lossless files go through an encode-decode cycle?
2. Is there any configuration that makes me say "use all available WiFi bandwidth, but let me listen to the original file"?
3. Is there any configuration that says "drop the video signal (for example, just display a static image of the cover of the album), and transmit the audio signal intact"?

Granted, this is not to be done for an extended period since the TV must remain on. Unlike the 3rd gen Apple TV, the 4th gen does not provide direct optical-out to the receiver.

Answer 1

I'm assuming you're talking about AirPlay Screen Mirroring from a Mac to an Apple TV. In that case, yes, you are loosing signal quality from compression-before-transmission and decompression-after-reception.

In particular, the audio part of the AirPlay Screen Mirroring is compressed using the AAC-ELD codec to ensure low-latency sound encoding. However, there is a signal loss involved.