> you need to decode and have every frame ready in less than 41 milliseconds, which is shockingly difficult even on high-end hardware
There appear to be multiple high-speed JP2K decoders on the market; Comprimato[0] include a calculator for their product and it claims that a $240 GPU from 2016 can decode 4k 4:4:4 at 72fps.
> Do I need to mention read speeds and network traffic? If every frame is, say, just 5MB, that is over 960 Megabits per second, saturating a Gigabit link.
According to Wikipedia, the DCP standard has a maximum bit rate for picture of 250Mbit/s[1]. My $60 home internet connection could stream that at almost 2x realtime.
> When you are calculating audio in real-time for 30 or more speakers, the compute costs add up, potentially into custom hardware / FPGA territory.
Dolby offer a software version of Atmos for soundtrack mastering that runs on a Mac Mini[2]. Real-time 128-channel object mixing was possible using consumer-grade hardware as early as EAX 5.0 in 2005[3], but Atmos does not need to be rendered in real time at a cinema, it can be done in advance and then during playback those pre-rendered PCM streams would be used which is a trivial amount of data to handle (under 20Mbit/s for a full 64-speaker array).
[0] https://comprimato.com/products/comprimato-jpeg2000/
[1] https://en.wikipedia.org/wiki/Digital_Cinema_Package#Picture...
[2] https://professionalsupport.dolby.com/s/article/What-are-the...
[3] https://en.wikipedia.org/wiki/Environmental_Audio_Extensions...