New H.265 twice as efficient as H.264!

[Penton-Man]

Originally Posted by Teazle

Idk how they squish it so small.

Enviable hydraulics using the principle of force-multiplication?

YouTube

Seriously,
D-Cinema uses JPEG2000 compression algorithm in its lossy compression mode. It is especially great for high resolution at relatively high data rates and also includes scalability features to simultaneously store 2K and 4K images (as different layers, if you will).

The way it works is that the 4K DCP contains a 2K image plus the differences between the 2K and the 4K image, which doesn’t add a helluva a lot to the total file size….actually a relatively small percentage.

By DCI, the max. allowable data rate is 250Mbit/s. At the maximum (constant) data rate of 250 Mbit/s, a two hour movie would result in a DCP of around 230 GB (image only)…which would give maximum allowable quality per DCI spec. To make DCPs as compact as possible in order to save space, etc., in practice, variable data rates between 80 Mbit/s - 150 Mbit/s usually lead to results which are deemed acceptable by the studios.

In fact, most of the encoding systems default to ~125 Mbit/s for just 2K content. At a data rate of 125 Mbit/s, a two hour movie would result in a DCP of around 115 GBytes in size (image only). Add on a small percentage for the differences between 2K and 4K rez and the file size is not bumped up that much.