Faster SD Cards For 4K And Even 8K Video Are Coming Soon

[Paul2]

A new class of SD cards that can record and access 4K and 8K video much more quickly is on its way later this year.The SD Association has released the SD 5.0 specification to answer market needs with a "video speed Class" SD cards.

The new SD cards will allow users to record and access multiple 4K video files simultaneously, while current SD cards can handle only one 4K file at a time.

The cards have a special controller to handle the faster recording and extraction of 4K and 8K video, but the cards will still be compatible with existing SD card slots.

Consumers will capture memories at their devices' best quality by following device manufacturer recommendations and matching the Video Speed Class mark on their device to an SD memory card with the same Video Speed Class mark. The new marks will appear on SDHC and SDXC UHS-I and UHS-II memory cards.

The new Video Speed Class maintains the tradition of ensuring guaranteed minimum performance levels as the familiar Speed Class and UHS Speed Class systems do today.



The speed class types include: Speed Class (C2, C4, C6 and C10), UHS Speed Class (U1 and U3) and now Video Speed Class (V6, V10, V30, V60 and V90).

Minimum speeds will range from 6MB to 90 MB per second. The fastest options, V60 and V90, support 8K resolution, while V6, V10 and V30 capture high-definition and 4K resolution.

http://cdrinfo.com/Sections/News/Details.aspx?NewsId=45692

Most SD Cards nowadays are Class 10 which can write or record up to a consistence speed of 10 Mbytes per second or 80 Mbits per second.  Some newer and a bit more expensive cards that have a UHS Class Speed of U3 can write/record up to a constant speed of 30 Mbytes per second or 240 mbits per second.

But the latest and newest SD cards that are about to come out soon can write/record up to 60 MBytes per second which equals 480 mbits per second and the fastest one can write/record up to 90 Mbytes per second or 720 Mbits per a second.

These newest yet to be release cards has a "V" marking to make it simpler to understand the speed i think.  Such as V90 means up to constant video speed of 90 Mbytes per second or V60 which means Video speed of 60 Mbytes per second.  These faster cards are probably going to be more expensive than V30 or V10 cards since it new and perform much faster.

At 90 Mbytes per second speed, its possible to record 8K video @ 60fps @ 8 bits per channel @ 4:2:0 Y:Cb:Cr color sampling with MPEG-4 compression of roughly 40:1 which equals 600 mbits per second.  Or even better, use MPEG-5 compressor which is more efficient than MPEG-4 i think.  MPEG-5 codec is also called HEVC or H.265 codec.  So at 600 mbps, mpeg-5 might looks better than mpeg-4 i think.

40:1 means 40 times the video data has been remove or thrown away or "compress".  Pretty cool.

Or at 90 Mbytes speed, one can record 4k video with higher color bitrate of 10 bit per channel, and or higher color sampling of 4:2:2 instead of 4:2:0 and still get lesser compression than 30 Mbytes speed cards.