Sony is working on a new codec to replace XAVC, which is based on the older H.264 compression standard.
The new codec is called XEVC according to leaks, based around H.265 (HEVC) Version 2. This supports Bayer RAW encoding, 8K and 12bit 4K at data rates efficient enough for almost any media, even current SD cards.
As well as the 8K RAW, new 4K and 2K RGB 4:4:4 formats (lossless compressed) make an appearance for the ultimate in non-RAW image quality.
In addition there are 10bit and 14bit 4K Proxy recording modes at just 20Mbit – very useful
1080p now goes to 240fps at up to 10bit, while the highest resolutions and bit-depths are reserved for 24p.
H.265 has double the image quality of H.264 at the same bitrate.
It is possible the long awaited A7S III will have XEVC to make it a big step up, especially if it is paired with the recently leaked 8K full frame sensor with full pixel readout designed for mirrorless cameras.
It’s also possible XEVC will make its first appearance in a professional FS7-style camera or as has happened in the past, a non-interchangeable zoom lens camcorder (boooo).
One other thing I would love to see from XEVC is a more friendly folder and file structure, with support at least in XEVC-S on consumer cameras for recording MOV files to the same directory as photos. I dislike having to navigate the PRIVATE folder structure every time to get at my files. Also from a usability point of view it would be great to have a better thumbnail stored for each recording, as well as more shooting-related meta-data in the XML file alongside. The current high quality thumbnail is very slow to load in XAVC view on Sony’s mirrorless cameras and in normal playback mode is incredibly pixilated.