What’s the difference between HDMI 2.0 and HDMI 2.0 b?
HDMI v2.0b is an incremental update to the HDMI v2.0 specification, and offers no increased bandwidth compared to its predecessor, only improvements in licensing terms. The $200 question surrounds HDR video transmission over HDMI; the HDMI 2.0 b standard prohibits “link compression” which is what enables clean passage of high-bandwidth footage at 4K or higher resolutions through older versions of the protocol like HDMI 1.4 and below. Meaning that if you want to pass 4K/HDR content between two compliant devices, your cables need to be (and will likely always be) “High Speed”. Without going into too much technical detail on how this entails details about using single-link vs dual-link, etc., the gist is that you need a direct connection from one device to another, which limits flexibility and ease of use for many users. The fix to this problem is likely already in the works. HDMI Licensing has already specified v2.1, which will offer higher data bandwidth, so 4K/60 at 4:4:4 chroma subsampling with 8 bits per color channel support should be possible down the road. By adding HDR metadata to content, it’s possible for devices with lower bandwidth to display HDR video, but only on the assumption that they’ll have good tone-mapping algorithms. This is an area where quality displays will shine vs cheaper LCD panels. Cheaper TVs are already showing poorer color accuracy and less vibrancy compared to proper high-quality panels due to poor calibration.